xnu-517.tar.gz
[apple/xnu.git] / osfmk / ppc / savearea_asm.s
index d3891b01978e2c7649472cd064b95e29a7b6297a..fe332b8640a3a557eec06398d02e581cccc8f513 100644 (file)
@@ -3,19 +3,22 @@
  *
  * @APPLE_LICENSE_HEADER_START@
  * 
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License").  You may not use this file except in compliance with the
- * License.  Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
+ * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
  * 
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
  * 
  * @APPLE_LICENSE_HEADER_END@
  */
 #include <ppc/exception.h>
 #include <ppc/Performance.h>
 #include <ppc/exception.h>
-#include <ppc/pmap_internals.h>
 #include <ppc/savearea.h>
 #include <mach/ppc/vm_param.h>
        
                        .text
 
+/* Register usage conventions in this code:
+ *     r9 = return address
+ * r10 = per-proc ptr
+ * r11 = MSR at entry
+ * cr6 = feature flags (ie, pf64Bit)
+ *
+ * Because much of this code deals with physical addresses,
+ * there are parallel paths for 32- and 64-bit machines.
+ */
 /*
- *                     This routine will add a savearea block to the free list.
- *                     Note really well: we can take NO exceptions of any kind,
- *                     including a PTE miss once the savearea lock is held. That's
- *                     a guaranteed deadlock.  That means we must disable for interrutions
- *                     and turn all translation off.
+ * ***********************
+ * * s a v e _ q u e u e *
+ * ***********************
  *
+ *     void save_queue(ppnum_t pagenum);
+ *
+ *                     This routine will add a savearea block to the free list.
  *                     We also queue the block to the free pool list.  This is a
  *                     circular double linked list. Because this block has no free entries,
  *                     it gets queued to the end of the list
- *
  */
-
                        .align  5
                        .globl  EXT(save_queue)
 
 LEXT(save_queue)
+            mflr       r9                                                      ; get return address
+            mr         r8,r3                                           ; move pagenum out of the way
+            bl         saveSetup                                       ; turn translation off, 64-bit on, load many regs
+            bf--       pf64Bitb,saveQueue32            ; skip if 32-bit processor
+            
+            sldi       r2,r8,12                                        ; r2 <-- phys address of page
+                       li              r8,sac_cnt                                      ; Get the number of saveareas per page
+                       mr              r4,r2                                           ; Point to start of chain
+                       li              r0,SAVempty                                     ; Get empty marker
 
-                       mfsprg  r9,2                                            ; Get the feature flags
-                       mr              r11,r3                                          ; Save the block
-                       mtcrf   0x04,r9                                         ; Set the features                      
-                       mfmsr   r12                                                     ; Get the MSR
-                       rlwinm  r12,r12,0,MSR_FP_BIT+1,MSR_FP_BIT-1     ; Force floating point off
-                       rlwinm  r12,r12,0,MSR_VEC_BIT+1,MSR_VEC_BIT-1   ; Force vectors off
-                       lis             r10,hi16(EXT(saveanchor))       ; Get the high part of the anchor
-                       andi.   r3,r12,0x7FCF                           ; Turn off all translation and rupts
-                       ori             r10,r10,lo16(EXT(saveanchor))   ; Bottom half of the anchor 
-
-                       bt              pfNoMSRirb,sqNoMSR                      ; No MSR...
-
-                       mtmsr   r3                                                      ; Translation and all off
-                       isync                                                           ; Toss prefetch
-                       b               sqNoMSRx
-                       
-sqNoMSR:       li              r0,loadMSR                                      ; Get the MSR setter SC
-                       sc                                                                      ; Set it
-sqNoMSRx:
-                       
-                       rlwinm. r3,r11,0,0,19                           ; (TEST/DEBUG)
-#if 0
-                       bne+    notrapit                                        ; (TEST/DEBUG)
-                       BREAKPOINT_TRAP                                         ; (TEST/DEBUG) 
-notrapit:                                                                              ; (TEST/DEBUG)
-#endif
+saveQueue64a:  
+            addic.     r8,r8,-1                                        ; Keep track of how many we did
+                       stb             r0,SAVflags+2(r4)                       ; Set empty
+                       addi    r7,r4,SAVsize                           ; Point to the next slot
+                       ble-    saveQueue64b                            ; We are done with the chain
+                       std             r7,SAVprev(r4)                          ; Set this chain
+                       mr              r4,r7                                           ; Step to the next
+                       b               saveQueue64a                            ; Fill the whole block...
+
+saveQueue64b:
+                       bl              savelock                                        ; Go lock the save anchor 
 
+                       ld              r7,SVfree(0)                            ; Get the free save area list anchor 
+                       lwz             r6,SVfreecnt(0)                         ; Get the number of free saveareas
 
+                       std             r2,SVfree(0)                            ; Queue in the new one 
+                       addi    r6,r6,sac_cnt                           ; Count the ones we are linking in 
+                       std             r7,SAVprev(r4)                          ; Queue the old first one off of us
+                       stw             r6,SVfreecnt(0)                         ; Save the new count
+                       b               saveQueueExit
+
+            ; Handle 32-bit processor.
+            
+saveQueue32:            
+            slwi       r2,r8,12                                        ; r2 <-- phys address of page
                        li              r8,sac_cnt                                      ; Get the number of saveareas per page
-                       mr              r4,r11                                          ; Point to start of chain
+                       mr              r4,r                                          ; Point to start of chain
                        li              r0,SAVempty                                     ; Get empty marker
 
-sqchain:       addic.  r8,r8,-1                                        ; Keep track of how many we did
+saveQueue32a:  
+            addic.     r8,r8,-1                                        ; Keep track of how many we did
                        stb             r0,SAVflags+2(r4)                       ; Set empty
-                       addi    r9,r4,SAVsize                           ; Point to the next slot
-                       ble-    sqchaindn                                       ; We are done with the chain
-                       stw             r9,SAVprev(r4)                          ; Set this chain
-                       mr              r4,r9                                           ; Step to the next
-                       b               sqchain                                         ; Fill the whole block...
-
-                       .align  5
+                       addi    r7,r4,SAVsize                           ; Point to the next slot
+                       ble-    saveQueue32b                            ; We are done with the chain
+                       stw             r7,SAVprev+4(r4)                        ; Set this chain
+                       mr              r4,r7                                           ; Step to the next
+                       b               saveQueue32a                            ; Fill the whole block...
 
-sqchaindn:     mflr    r9                                                      ; Save the return address
+saveQueue32b:
                        bl              savelock                                        ; Go lock the save anchor 
 
-                       lwz             r7,SVfree(r10)                          ; Get the free save area list anchor 
-                       lwz             r6,SVfreecnt(r10)                       ; Get the number of free saveareas
+                       lwz             r7,SVfree+4(0)                          ; Get the free save area list anchor 
+                       lwz             r6,SVfreecnt(0)                         ; Get the number of free saveareas
 
-                       stw             r11,SVfree(r10)                         ; Queue in the new one 
+                       stw             r2,SVfree+4(0)                          ; Queue in the new one 
                        addi    r6,r6,sac_cnt                           ; Count the ones we are linking in 
-                       stw             r7,SAVprev(r4)                          ; Queue the old first one off of us
-                       stw             r6,SVfreecnt(r10)                       ; Save the new count
-                       
+                       stw             r7,SAVprev+4(r4)                        ; Queue the old first one off of us
+                       stw             r6,SVfreecnt(0)                         ; Save the new count
+
+saveQueueExit:                                                                 ; join here from 64-bit path            
                        bl              saveunlock                                      ; Unlock the list and set the adjust count
-                       
                        mtlr    r9                                                      ; Restore the return
-                       mtmsr   r12                                                     ; Restore interrupts and translation 
-                       isync                                                           ; Dump any speculations 
 
 #if FPVECDBG
-                       mfsprg  r2,0                                            ; (TEST/DEBUG)
-                       lwz             r2,next_savearea(r2)            ; (TEST/DEBUG)
+                       mfsprg  r2,1                                            ; (TEST/DEBUG)
                        mr.             r2,r2                                           ; (TEST/DEBUG)
-                       beqlr-                                                          ; (TEST/DEBUG)
+                       beq--   saveRestore                                     ; (TEST/DEBUG)
                        lis             r0,hi16(CutTrace)                       ; (TEST/DEBUG)
                        li              r2,0x2201                                       ; (TEST/DEBUG)
                        oris    r0,r0,lo16(CutTrace)            ; (TEST/DEBUG)
                        sc                                                                      ; (TEST/DEBUG)
 #endif
-
-                       blr                                                                     ; Leave... 
+            b          saveRestore                                     ; Restore interrupts and translation
 
 /*
- *                     This routine will obtain a savearea.
- *                     Note really well: we can take NO exceptions of any kind,
- *                     including a PTE miss during this process. That's
- *                     a guaranteed deadlock or screwup.  That means we must disable for interrutions
- *                     and turn all translation off.
- *
- *                     We pass back the virtual address of the one we just obtained
- *                     or a zero if none to allocate.
+ * *****************************
+ * * s a v e _ g e t _ i n i t *
+ * *****************************
  *
- *                     First we try the local list.  If that is below a threshold, we will
- *                     lock the free list and replenish.
- *
- *                     If there are no saveareas in either list, we will install the 
- *                     backpocket and choke.
- *
- *                     The save_get_phys call assumes that translation and interruptions are
- *                     already off and that the returned address is physical.
+ *     addr64_t  save_get_init(void);
  *
  *                     Note that save_get_init is used in initial processor startup only.  It
  *                     is used because translation is on, but no tables exist yet and we have
  *                     no V=R BAT registers that cover the entire physical memory.
- *
- *
- *                     NOTE!!! NEVER USE R0, R2, or R12 IN HERE THAT WAY WE DON'T NEED A
- *                     STACK FRAME IN FPU_SAVE, FPU_SWITCH, VEC_SAVE, OR VEC_SWITCH.
  */
                        .align  5
                        .globl  EXT(save_get_init)
 
 LEXT(save_get_init)
+            mflr       r9                                                      ; get return address
+            bl         saveSetup                                       ; turn translation off, 64-bit on, load many regs
+            bfl--      pf64Bitb,saveGet32                      ; Get r3 <- savearea, r5 <- page address (with SAC)
+            btl++      pf64Bitb,saveGet64                      ; get one on a 64-bit machine
+            bl         saveRestore                                     ; restore translation etc
+            mtlr       r9
+            
+            ; unpack the physaddr in r3 into a long long in (r3,r4)
+            
+            mr         r4,r3                                           ; copy low word of phys address to r4
+            li         r3,0                                            ; assume upper word was 0
+            bflr--     pf64Bitb                                        ; if 32-bit processor, return
+            srdi       r3,r4,32                                        ; unpack reg64_t to addr64_t on 64-bit machine
+            rlwinm     r4,r4,0,0,31
+            blr
+            
 
-                       mfsprg  r9,2                                            ; Get the feature flags
-                       mfmsr   r12                                                     ; Get the MSR 
-                       rlwinm  r12,r12,0,MSR_FP_BIT+1,MSR_FP_BIT-1     ; Force floating point off
-                       rlwinm  r12,r12,0,MSR_VEC_BIT+1,MSR_VEC_BIT-1   ; Force vectors off
-                       mtcrf   0x04,r9                                         ; Set the features                      
-                       andi.   r3,r12,0x7FCF                           ; Turn off all translation and interrupts
-
-                       bt              pfNoMSRirb,sgiNoMSR                     ; No MSR...
-
-                       mtmsr   r3                                                      ; Translation and all off
-                       isync                                                           ; Toss prefetch
-                       b               sgiGetPhys                                      ; Go get the savearea...
-                       
-sgiNoMSR:      li              r0,loadMSR                                      ; Get the MSR setter SC
-                       sc                                                                      ; Set it
-
-sgiGetPhys:    mflr    r11                                                     ; Save R11 (save_get_phys does not use this one)
-                       bl              EXT(save_get_phys)                      ; Get a savearea
-                       mtlr    r11                                                     ; Restore return
-                       
-                       mtmsr   r12                                                     ; Restore translation and exceptions
-                       isync                                                           ; Make sure about it
-                       blr                                                                     ; Return...
+/*
+ * *******************
+ * * s a v e _ g e t *
+ * *******************
+ *
+ *     savearea *save_get(void);
+ *
+ *                     Allocate a savearea, returning a virtual address.  NOTE: we must preserve
+ *                     r0, r2, and r12.  Our callers in cswtch.s depend on this.
+ */
                        .align  5
                        .globl  EXT(save_get)
 
 LEXT(save_get)
-                       
-                       crclr   cr1_eq                                          ; Clear CR1_eq to indicate we want virtual address
-                       mfsprg  r9,2                                            ; Get the feature flags
-                       mfmsr   r11                                                     ; Get the MSR 
-                       rlwinm. r3,r11,0,MSR_EE_BIT,MSR_EE_BIT  ;       Are interrupts enabled here?
-                       beq+    sgnomess                                        ; Nope, do not mess with fp or vec...
-                       rlwinm  r11,r11,0,MSR_FP_BIT+1,MSR_FP_BIT-1     ; Force floating point off
-                       rlwinm  r11,r11,0,MSR_VEC_BIT+1,MSR_VEC_BIT-1   ; Force vectors off
-
-sgnomess:      mtcrf   0x04,r9                                         ; Set the features                      
-                       andi.   r3,r11,0x7FCF                           ; Turn off all translation and interrupts
-
-                       bt              pfNoMSRirb,sgNoMSR                      ; No MSR...
-
-                       mtmsr   r3                                                      ; Translation and all off
-                       isync                                                           ; Toss prefetch
-                       b               csaveget
-                       
-sgNoMSR:       mr              r9,r0                                           ; Save this
-                       li              r0,loadMSR                                      ; Get the MSR setter SC
-                       sc                                                                      ; Set it
-                       mr              r0,r9                                           ; Restore it
+            mflr       r9                                                      ; get return address
+            mr         r5,r0                                           ; copy regs before saveSetup nails them
+            bl         saveSetup                                       ; turn translation off, 64-bit on, load many regs
+            bf--       pf64Bitb,svgt1                          ; skip if 32-bit processor
+            
+            std                r5,tempr0(r10)                          ; save r0 in per-proc across call to saveGet64
+            std                r2,tempr2(r10)                          ; and r2
+            std                r12,tempr4(r10)                         ; and r12
+            bl         saveGet64                                       ; get r3 <- savearea, r5 <- page address (with SAC)
+            ld         r0,tempr0(r10)                          ; restore callers regs
+            ld         r2,tempr2(r10)
+            ld         r12,tempr4(r10)
+            b          svgt2
+            
+svgt1:                                                                                 ; handle 32-bit processor
+            stw                r5,tempr0+4(r10)                        ; save r0 in per-proc across call to saveGet32
+            stw                r2,tempr2+4(r10)                        ; and r2
+            stw                r12,tempr4+4(r10)                       ; and r12
+            bl         saveGet32                                       ; get r3 <- savearea, r5 <- page address (with SAC)
+            lwz                r0,tempr0+4(r10)                        ; restore callers regs
+            lwz                r2,tempr2+4(r10)
+            lwz                r12,tempr4+4(r10)
+            
+svgt2:
+                       lwz             r5,SACvrswap+4(r5)                      ; Get the virtual to real translation (only need low word)
+            mtlr       r9                                                      ; restore return address
+            xor                r3,r3,r5                                        ; convert physaddr to virtual
+            rlwinm     r3,r3,0,0,31                            ; 0 upper word if a 64-bit machine
 
-                       b               csaveget                                        ; Join the common...
-
-                       .align  5
-                       .globl  EXT(save_get_phys)
-
-LEXT(save_get_phys)
-                       
-                       crset   cr1_eq                                          ; Clear CR1_ne to indicate we want physical address
-
-csaveget:      mfsprg  r9,0                                            ; Get the per proc
-                       lis             r10,hi16(EXT(saveanchor))       ; Get the high part of the anchor
-                       lwz             r8,lclfreecnt(r9)                       ; Get the count
-                       lwz             r3,lclfree(r9)                          ; Get the start of local savearea list
-                       cmplwi  r8,LocalSaveMin                         ; Are we too low?
-                       ori             r10,r10,lo16(EXT(saveanchor))   ; Bottom half of the anchor 
-                       ble-    sglow                                           ; We are too low and need to grow list...
-                       
-sgreserve:     lis             r10,0x5555                                      ; Get top of empty indication
-                       li              r6,0                                            ; zero value
-                       lwz             r4,SAVprev(r3)                          ; Chain to the next one
-                       stw             r6,SAVflags(r3)                         ; Clear flags
-                       ori             r10,r10,0x5555                          ; And the bottom
-                       subi    r8,r8,1                                         ; Back down count
-                       stw             r10,SAVprev(r3)                         ; Trash this
-                       stw             r10,SAVlevel(r3)                        ; Trash this
-                       stw             r4,lclfree(r9)                          ; Unchain first savearea
-                       rlwinm  r5,r3,0,0,19                            ; Back up to first page where SAC is
-                       stw             r10,SAVact(r3)                          ; Trash this
-                       stw             r8,lclfreecnt(r9)                       ; Set new count
-                       
-                       btlr+   cr1_eq                                          ; Return now if physical request
-                       
-                       lwz             r5,SACvrswap(r5)                        ; Get the virtual to real translation
-                       
-                       mtmsr   r11                                                     ; Restore translation and exceptions
-                       isync                                                           ; Make sure about it
-       
 #if FPVECDBG
-;                      Note: we do not trace the physical request because this ususally comes from the
-;                      exception vector code
-
-                       mr              r6,r0                                           ; (TEST/DEBUG)
-                       mr              r7,r2                                           ; (TEST/DEBUG) 
+            mr         r6,r0                                           ; (TEST/DEBUG)
+            mr         r7,r2                                           ; (TEST/DEBUG)
+                       mfsprg  r2,1                                            ; (TEST/DEBUG)
+                       mr.             r2,r2                                           ; (TEST/DEBUG)
+                       beq--   svgDBBypass                                     ; (TEST/DEBUG)
                        lis             r0,HIGH_ADDR(CutTrace)          ; (TEST/DEBUG)
                        li              r2,0x2203                                       ; (TEST/DEBUG)
                        oris    r0,r0,LOW_ADDR(CutTrace)        ; (TEST/DEBUG)
                        sc                                                                      ; (TEST/DEBUG) 
-                       mr              r0,r6                                           ; (TEST/DEBUG)
-                       mr              r2,r7                                           ; (TEST/DEBUG)
+svgDBBypass:                                                                   ; (TEST/DEBUG)
+            mr         r0,r6                                           ; (TEST/DEBUG)
+            mr         r2,r7                                           ; (TEST/DEBUG) 
 #endif                 
-                       
-                       xor             r3,r3,r5                                        ; Get the virtual address 
-                       blr                                                                     ; Leave...
+            b          saveRestore                                     ; restore MSR and return to our caller
+            
+            
+/*
+ * ***********************************
+ * * s a v e _ g e t _ p h y s _ 3 2 *
+ * ***********************************
+ *
+ *     reg64_t save_get_phys(void);
+ *
+ *                     This is the entry normally called from lowmem_vectors.s with
+ *                     translation and interrupts already off.
+ *                     MUST NOT TOUCH CR7
+ */
+                       .align  5
+                       .globl  EXT(save_get_phys_32)
 
-;
-;                      Here is the slow path which is executed when there are not enough in the local list
-;
-                                       
+LEXT(save_get_phys_32)
+            mfsprg     r10,0                                           ; get the per-proc ptr
+                       b               saveGet32                                       ; Get r3 <- savearea, r5 <- page address (with SAC)
+
+
+/*
+ * ***********************************
+ * * s a v e _ g e t _ p h y s _ 6 4 *
+ * ***********************************
+ *
+ *     reg64_t save_get_phys_64(void);
+ *
+ *                     This is the entry normally called from lowmem_vectors.s with
+ *                     translation and interrupts already off, and in 64-bit mode.
+ *                     MUST NOT TOUCH CR7
+ */
                        .align  5
-                                               
-sglow:         mflr    r9                                                      ; Save the return
+                       .globl  EXT(save_get_phys_64)
+
+LEXT(save_get_phys_64)
+            mfsprg     r10,0                                           ; get the per-proc ptr
+                       b               saveGet64                                       ; Get r3 <- savearea, r5 <- page address (with SAC)
+            
+
+/*
+ * *********************
+ * * s a v e G e t 6 4 *
+ * *********************
+ *
+ *                     This is the internal routine to allocate a savearea on a 64-bit processor.  
+ *                     Note that we must not take any exceptions of any kind, including PTE misses, as that
+ *                     would deadlock trying to reenter this routine.  We pass back the 64-bit physical address.
+ *                     First we try the local list.  If that is below a threshold, we try the global free list,
+ *                     which requires taking a lock, and replenish.  If there are no saveareas in either list,
+ *                     we will install the  backpocket and choke.  This routine assumes that the caller has
+ *                     turned translation off, masked interrupts,  turned on 64-bit mode, and set up:
+ *                             r10 = per-proc ptr
+ *
+ *                     We return:
+ *                             r3 = 64-bit physical address of the savearea
+ *                             r5 = 64-bit physical address of the page the savearea is in, with SAC
+ *
+ *                     We destroy:
+ *                             r2-r8.
+ *             
+ *                     MUST NOT TOUCH CR7
+ */
+
+saveGet64:            
+                       lwz             r8,lclfreecnt(r10)                      ; Get the count
+                       ld              r3,lclfree(r10)                         ; Get the start of local savearea list
+                       cmplwi  r8,LocalSaveMin                         ; Are we too low?
+                       ble--   saveGet64GetGlobal                      ; We are too low and need to grow list...
+
+            ; Get it from the per-processor local list.
+            
+saveGet64GetLocal:
+            li         r2,0x5555                                       ; get r2 <-- 0x55555555 55555555, our bugbug constant
+                       ld              r4,SAVprev(r3)                          ; Chain to the next one
+                       oris    r2,r2,0x5555
+                       subi    r8,r8,1                                         ; Back down count
+            rldimi     r2,r2,32,0
+
+                       std             r2,SAVprev(r3)                          ; bug next ptr
+                       stw             r2,SAVlevel(r3)                         ; bug context ID
+            li         r6,0
+                       std             r4,lclfree(r10)                         ; Unchain first savearea
+                       stw             r2,SAVact(r3)                           ; bug activation ptr
+                       rldicr  r5,r3,0,51                                      ; r5 <-- page ptr, where SAC is kept
+                       stw             r8,lclfreecnt(r10)                      ; Set new count
+                       stw             r6,SAVflags(r3)                         ; clear the flags
+
+            blr
+
+            ; Local list was low so replenish from global list.
+            ;   r7 = return address to caller of saveGet64
+            ;   r8 = lclfreecnt
+            ;  r10 = per-proc ptr
+            
+saveGet64GetGlobal:
+            mflr       r7                                                      ; save return adress
+                       subfic  r5,r8,LocalSaveTarget           ; Get the number of saveareas we need to grab to get to target
                        bl              savelock                                        ; Go lock up the anchor
-                       mtlr    r9                                                      ; Restore the return
                        
-                       subfic  r5,r8,LocalSaveTarget           ; Get the number of saveareas we need to grab to get to target
-                       lwz             r9,SVfreecnt(r10)                       ; Get the number on this list
-                       lwz             r8,SVfree(r10)                          ; Get the head of the save area list 
+                       lwz             r2,SVfreecnt(0)                         ; Get the number on this list
+                       ld              r8,SVfree(0)                            ; Get the head of the save area list 
                        
-                       sub             r3,r9,r5                                        ; Get number left after we swipe enough for local list
-                       srawi   r3,r3,31                                        ; Get 0 if enough or 0xFFFFFFFF if not
+                       sub             r3,r2,r5                                        ; Get number left after we swipe enough for local list
+                       sradi   r3,r3,63                                        ; Get 0 if enough or -1 if not
                        andc    r4,r5,r3                                        ; Get number to get if there are enough, 0 otherwise
-                       and             r5,r9,r3                                        ; Get 0 if there are enough, number on list otherwise
-                       or.             r5,r4,r5                                        ; Get the number we will move
-                       beq-    sgnofree                                        ; There are none to get...
+                       and             r5,r2,r3                                        ; Get 0 if there are enough, number on list otherwise
+                       or.             r5,r4,r5                                        ; r5 <- number we will move from global to local list
+                       beq--   saveGet64NoFree                         ; There are none to get...
                        
                        mtctr   r5                                                      ; Get loop count
                        mr              r6,r8                                           ; Remember the first in the list
-                       
-sgtrimf:       bdz             sgtfdone                                        ; Count down and branch when we hit 0...
-                       lwz             r8,SAVprev(r8)                          ; Get the next
-                       b               sgtrimf                                         ; Keep going...
 
-                       .align  5
-                       
-sgtfdone:      lwz             r7,SAVprev(r8)                          ; Get the next one
-                       lwz             r4,SVinuse(r10)                         ; Get the in use count
-                       sub             r9,r9,r5                                        ; Count down what we stole
-                       stw             r7,SVfree(r10)                          ; Set the new first in list
+saveGet64c:
+            bdz                saveGet64d                                      ; Count down and branch when we hit 0...
+                       ld              r8,SAVprev(r8)                          ; Get the next
+                       b               saveGet64c                                      ; Keep going...
+
+saveGet64d:                    
+            ld         r3,SAVprev(r8)                          ; Get the next one
+                       lwz             r4,SVinuse(0)                           ; Get the in use count
+                       sub             r2,r2,r5                                        ; Count down what we stole
+                       std             r3,SVfree(0)                            ; Set the new first in list
                        add             r4,r4,r5                                        ; Count the ones we just put in the local list as "in use"
-                       stw             r9,SVfreecnt(r10)                       ; Set the new count
-                       mfsprg  r9,0                                            ; Get the per proc
-                       stw             r4,SVinuse(r10)                         ; Set the new in use count
+                       stw             r2,SVfreecnt(0)                         ; Set the new count
+                       stw             r4,SVinuse(0)                           ; Set the new in use count
                        
-                       lwz             r4,lclfree(r9)                          ; Get the old head of list
-                       lwz             r3,lclfreecnt(r9)                       ; Get the old count
-                       stw             r6,lclfree(r9)                          ; Set the new head of the list
+                       ld              r4,lclfree(r10)                         ; Get the old head of list
+                       lwz             r3,lclfreecnt(r10)                      ; Get the old count
+                       std             r6,lclfree(r10)                         ; Set the new head of the list
                        add             r3,r3,r5                                        ; Get the new count
-                       stw             r4,SAVprev(r8)                          ; Point to the old head
-                       stw             r3,lclfreecnt(r9)                       ; Set the new count
+                       std             r4,SAVprev(r8)                          ; Point to the old head
+                       stw             r3,lclfreecnt(r10)                      ; Set the new count
 
-                       mflr    r9                                                      ; Save the return
                        bl              saveunlock                                      ; Update the adjust field and unlock
-                       mtlr    r9                                                      ; Restore return
-                       b               csaveget                                        ; Start over and finally allocate the savearea...
-                       
-;
-;                      The local list is below the repopulate threshold and the free list is empty.
-;                      First we check if there are any left in the local list and if so, we allow
-;                      them to be allocated.  If not, we release the backpocket list and choke.  
-;                      There is nothing more that we can do at this point.  Hopefully we stay alive
-;                      long enough to grab some much-needed panic information.
-;
-                       
-sgnofree:      mfsprg  r9,0                                            ; Get the per proc
-                       lwz             r8,lclfreecnt(r9)                       ; Get the count
-                       lwz             r3,lclfree(r9)                          ; Get the start of local savearea list
+            mtlr       r7                                                      ; restore return address
+                       b               saveGet64                                       ; Start over and finally allocate the savearea...
+                       
+            ; The local list is below the repopulate threshold and the global list is empty.
+            ; First we check if there are any left in the local list and if so, we allow
+            ; them to be allocated.  If not, we release the backpocket list and choke.  
+            ; There is nothing more that we can do at this point.  Hopefully we stay alive
+            ; long enough to grab some much-needed panic information.
+            ;   r7 = return address to caller of saveGet64 
+            ;  r10 = per-proc ptr
+
+saveGet64NoFree:                       
+                       lwz             r8,lclfreecnt(r10)                      ; Get the count
                        mr.             r8,r8                                           ; Are there any reserve to get?
-
-                       mflr    r9                                                      ; Save the return
-                       beq-    sgchoke                                         ; No, go choke and die...
+                       beq--   saveGet64Choke                          ; No, go choke and die...
                        bl              saveunlock                                      ; Update the adjust field and unlock
-                       mtlr    r9                                                      ; Restore return
-
-                       mfsprg  r9,0                                            ; Get the per proc again
-                       lwz             r3,lclfree(r9)                          ; Get the start of local savearea list
-                       lwz             r8,lclfreecnt(r9)                       ; Get the count
-                       b               sgreserve                                       ; We have some left, dip on in...
+                       ld              r3,lclfree(r10)                         ; Get the start of local savearea list
+                       lwz             r8,lclfreecnt(r10)                      ; Get the count
+            mtlr       r7                                                      ; restore return address
+                       b               saveGet64GetLocal                       ; We have some left, dip on in...
                        
-;
 ;                      We who are about to die salute you.  The savearea chain is messed up or
 ;                      empty.  Add in a few so we have enough to take down the system.
-;
 
-sgchoke:       lis             r9,hi16(EXT(backpocket))        ; Get high order of back pocket
+saveGet64Choke:
+            lis                r9,hi16(EXT(backpocket))        ; Get high order of back pocket
                        ori             r9,r9,lo16(EXT(backpocket))     ; and low part
                        
-                       lwz             r8,SVfreecnt(r9)                        ; Get the new number of free elements
-                       lwz             r7,SVfree(r9)                           ; Get the head of the chain
-                       lwz             r6,SVinuse(r10)                         ; Get total in the old list
+                       lwz             r8,SVfreecnt-saveanchor(r9)     ; Get the new number of free elements
+                       ld              r7,SVfree-saveanchor(r9)        ; Get the head of the chain
+                       lwz             r6,SVinuse(0)                           ; Get total in the old list
 
-                       stw             r8,SVfreecnt(r10)                       ; Set the new number of free elements
+                       stw             r8,SVfreecnt(0)                         ; Set the new number of free elements
                        add             r6,r6,r8                                        ; Add in the new ones
-                       stw             r7,SVfree(r10)                          ; Set the new head of the chain
-                       stw             r6,SVinuse(r10)                         ; Set total in the new list
+                       std             r7,SVfree(0)                            ; Set the new head of the chain
+                       stw             r6,SVinuse(0)                           ; Set total in the new list
 
+saveGetChokeJoin:                                                              ; join in the fun from 32-bit mode
                        lis             r0,hi16(Choke)                          ; Set choke firmware call
                        li              r7,0                                            ; Get a clear register to unlock
                        ori             r0,r0,lo16(Choke)                       ; Set the rest of the choke call
                        li              r3,failNoSavearea                       ; Set failure code
 
-                       sync                                                            ; Make sure all is committed
-                       stw             r7,SVlock(r10)                          ; Unlock the free list
+                       eieio                                                           ; Make sure all is committed
+                       stw             r7,SVlock(0)                            ; Unlock the free list
                        sc                                                                      ; System ABEND
 
 
-
 /*
- *                     This routine will return a savearea to the free list.
- *                     Note really well: we can take NO exceptions of any kind,
- *                     including a PTE miss once the savearea lock is held. That's
- *                     a guaranteed deadlock.  That means we must disable for interrutions
- *                     and turn all translation off.
- *
- *                     We take a virtual address for save_ret.  For save_ret_phys we
- *                     assume we are already physical/interrupts off and the address is physical.
+ * *********************
+ * * s a v e G e t 3 2 *
+ * *********************
  *
- *                     Here's a tricky bit, and important:
+ *                     This is the internal routine to allocate a savearea on a 32-bit processor.  
+ *                     Note that we must not take any exceptions of any kind, including PTE misses, as that
+ *                     would deadlock trying to reenter this routine.  We pass back the 32-bit physical address.
+ *                     First we try the local list.  If that is below a threshold, we try the global free list,
+ *                     which requires taking a lock, and replenish.  If there are no saveareas in either list,
+ *                     we will install the  backpocket and choke.  This routine assumes that the caller has
+ *                     turned translation off, masked interrupts, and set up:
+ *                             r10 = per-proc ptr
  *
- *                     When we trim the list, we NEVER trim the very first one.  This is because that is
- *                     the very last one released and the exception exit code will release the savearea
- *                     BEFORE it is done using it. Wouldn't be too good if another processor started
- *                     using it, eh?  So for this case, we are safe so long as the savearea stays on
- *                     the local list.  (Note: the exit routine needs to do this because it is in the 
- *                     process of restoring all context and it needs to keep it until the last second.)
+ *                     We return:
+ *                             r3 = 32-bit physical address of the savearea
+ *                             r5 = 32-bit physical address of the page the savearea is in, with SAC
  *
+ *                     We destroy:
+ *                             r2-r8.
  */
 
-;
-;                      Note: when called from interrupt enabled code, we want to turn off vector and
-;                      floating point because we can not guarantee that the enablement will not change
-;                      while we hold a copy of the MSR.  We force it off so that the lazy switcher will
-;                      turn it back on if used.  However, we need to NOT change it save_ret or save_get
-;                      is called with interrupts disabled.  This is because both of these routine are
-;                      called from within the context switcher and changing the enablement would be
-;                      very, very bad..... (especially from within the lazt switcher)
-;
+saveGet32:            
+                       lwz             r8,lclfreecnt(r10)                      ; Get the count
+                       lwz             r3,lclfree+4(r10)                       ; Get the start of local savearea list
+                       cmplwi  r8,LocalSaveMin                         ; Are we too low?
+                       ble-    saveGet32GetGlobal                      ; We are too low and need to grow list...
+
+            ; Get savearea from per-processor local list.
+            
+saveGet32GetLocal:
+            li         r2,0x5555                                       ; get r2 <-- 0x55555555, our bugbug constant
+                       lwz             r4,SAVprev+4(r3)                        ; Chain to the next one
+                       oris    r2,r2,0x5555
+                       subi    r8,r8,1                                         ; Back down count
 
-                       .align  5
-                       .globl  EXT(save_ret)
+                       stw             r2,SAVprev+4(r3)                        ; bug next ptr
+                       stw             r2,SAVlevel(r3)                         ; bug context ID
+            li         r6,0
+                       stw             r4,lclfree+4(r10)                       ; Unchain first savearea
+                       stw             r2,SAVact(r3)                           ; bug activation ptr
+                       rlwinm  r5,r3,0,0,19                            ; r5 <-- page ptr, where SAC is kept
+                       stw             r8,lclfreecnt(r10)                      ; Set new count
+                       stw             r6,SAVflags(r3)                         ; clear the flags
+
+            blr
+
+            ; Local list was low so replenish from global list.
+            ;   r7 = return address to caller of saveGet32
+            ;   r8 = lclfreecnt
+            ;  r10 = per-proc ptr
+            
+saveGet32GetGlobal:
+            mflr       r7                                                      ; save return adress
+                       subfic  r5,r8,LocalSaveTarget           ; Get the number of saveareas we need to grab to get to target
+                       bl              savelock                                        ; Go lock up the anchor
+                       
+                       lwz             r2,SVfreecnt(0)                         ; Get the number on this list
+                       lwz             r8,SVfree+4(0)                          ; Get the head of the save area list 
+                       
+                       sub             r3,r2,r5                                        ; Get number left after we swipe enough for local list
+                       srawi   r3,r3,31                                        ; Get 0 if enough or -1 if not
+                       andc    r4,r5,r3                                        ; Get number to get if there are enough, 0 otherwise
+                       and             r5,r2,r3                                        ; Get 0 if there are enough, number on list otherwise
+                       or.             r5,r4,r5                                        ; r5 <- number we will move from global to local list
+                       beq-    saveGet32NoFree                         ; There are none to get...
+                       
+                       mtctr   r5                                                      ; Get loop count
+                       mr              r6,r8                                           ; Remember the first in the list
 
-LEXT(save_ret)
+saveGet32c:
+            bdz                saveGet32d                                      ; Count down and branch when we hit 0...
+                       lwz             r8,SAVprev+4(r8)                        ; Get the next
+                       b               saveGet32c                                      ; Keep going...
 
-                       mfmsr   r12                                                     ; Get the MSR 
-                       rlwinm. r9,r12,0,MSR_EE_BIT,MSR_EE_BIT  ;       Are interrupts enabled here?
-                       beq+    EXT(save_ret_join)                      ; Nope, do not mess with fp or vec...
-                       rlwinm  r12,r12,0,MSR_FP_BIT+1,MSR_FP_BIT-1     ; Force floating point off
-                       rlwinm  r12,r12,0,MSR_VEC_BIT+1,MSR_VEC_BIT-1   ; Force vectors off
+saveGet32d:                    
+            lwz                r3,SAVprev+4(r8)                        ; Get the next one
+                       lwz             r4,SVinuse(0)                           ; Get the in use count
+                       sub             r2,r2,r5                                        ; Count down what we stole
+                       stw             r3,SVfree+4(0)                          ; Set the new first in list
+                       add             r4,r4,r5                                        ; Count the ones we just put in the local list as "in use"
+                       stw             r2,SVfreecnt(0)                         ; Set the new count
+                       stw             r4,SVinuse(0)                           ; Set the new in use count
+                       
+                       lwz             r4,lclfree+4(r10)                       ; Get the old head of list
+                       lwz             r3,lclfreecnt(r10)                      ; Get the old count
+                       stw             r6,lclfree+4(r10)                       ; Set the new head of the list
+                       add             r3,r3,r5                                        ; Get the new count
+                       stw             r4,SAVprev+4(r8)                        ; Point to the old head
+                       stw             r3,lclfreecnt(r10)                      ; Set the new count
 
-                       .globl  EXT(save_ret_join)
+                       bl              saveunlock                                      ; Update the adjust field and unlock
+            mtlr       r7                                                      ; restore return address
+                       b               saveGet32                                       ; Start over and finally allocate the savearea...
+                       
+            ; The local list is below the repopulate threshold and the global list is empty.
+            ; First we check if there are any left in the local list and if so, we allow
+            ; them to be allocated.  If not, we release the backpocket list and choke.  
+            ; There is nothing more that we can do at this point.  Hopefully we stay alive
+            ; long enough to grab some much-needed panic information.
+            ;   r7 = return address to caller of saveGet32
+            ;  r10 = per-proc ptr
+
+saveGet32NoFree:                       
+                       lwz             r8,lclfreecnt(r10)                      ; Get the count
+                       mr.             r8,r8                                           ; Are there any reserve to get?
+                       beq-    saveGet32Choke                          ; No, go choke and die...
+                       bl              saveunlock                                      ; Update the adjust field and unlock
+                       lwz             r3,lclfree+4(r10)                       ; Get the start of local savearea list
+                       lwz             r8,lclfreecnt(r10)                      ; Get the count
+            mtlr       r7                                                      ; restore return address
+                       b               saveGet32GetLocal                       ; We have some left, dip on in...
+                       
+;                      We who are about to die salute you.  The savearea chain is messed up or
+;                      empty.  Add in a few so we have enough to take down the system.
 
-LEXT(save_ret_join)
-                       crclr   cr1_eq                                          ; Clear CR1_ne to indicate we have virtual address
-                       mfsprg  r9,2                                            ; Get the feature flags
-                       rlwinm  r6,r3,0,0,19                            ; Round back down to the savearea page block
-                       lwz             r5,SACvrswap(r6)                        ; Get the conversion to real
-                       mtcrf   0x04,r9                                         ; Set the features                      
-                       mfsprg  r9,0                                            ; Get the per proc
-                       xor             r8,r3,r5                                        ; Get the real address of the savearea
-                       andi.   r3,r12,0x7FCF                           ; Turn off all translation and rupts
+saveGet32Choke:
+            lis                r9,hi16(EXT(backpocket))        ; Get high order of back pocket
+                       ori             r9,r9,lo16(EXT(backpocket))     ; and low part
+                       
+                       lwz             r8,SVfreecnt-saveanchor(r9)     ; Get the new number of free elements
+                       lwz             r7,SVfree+4-saveanchor(r9)      ; Get the head of the chain
+                       lwz             r6,SVinuse(0)                           ; Get total in the old list
 
-                       bt              pfNoMSRirb,srNoMSR                      ; No MSR...
+                       stw             r8,SVfreecnt(0)                         ; Set the new number of free elements
+                       add             r6,r6,r8                                        ; Add in the new ones (why?)
+                       stw             r7,SVfree+4(0)                          ; Set the new head of the chain
+                       stw             r6,SVinuse(0)                           ; Set total in the new list
+            
+            b          saveGetChokeJoin
 
-                       mtmsr   r3                                                      ; Translation and all off
-                       isync                                                           ; Toss prefetch
-                       b               srcommon
-                       
-                       .align  5
-                       
-srNoMSR:       li              r0,loadMSR                                      ; Get the MSR setter SC
-                       sc                                                                      ; Set it
-srNoMSRx:      b               srcommon                                        ; Join up below...
 
+/*
+ * *******************
+ * * s a v e _ r e t *
+ * *******************
+ *
+ *     void    save_ret(struct savearea *);                            // normal call
+ *     void    save_ret_wMSR(struct savearea *,reg64_t);       // passes MSR to restore as 2nd arg
+ *
+ *                     Return a savearea passed by virtual address to the free list.
+ *                     Note really well: we can take NO exceptions of any kind,
+ *                     including a PTE miss once the savearea lock is held. That's
+ *                     a guaranteed deadlock.  That means we must disable for interrutions
+ *                     and turn all translation off.
+ */
+            .globl     EXT(save_ret_wMSR)                      ; alternate entry pt w MSR to restore in r4
+            
+LEXT(save_ret_wMSR)
+            crset      31                                                      ; set flag for save_ret_wMSR
+            b          svrt1                                           ; join common code
+            
+            .align     5
+            .globl     EXT(save_ret)
+            
+LEXT(save_ret)
+            crclr      31                                                      ; clear flag for save_ret_wMSR
+svrt1:                                                                                 ; join from save_ret_wMSR
+            mflr       r9                                                      ; get return address
+            rlwinm     r7,r3,0,0,19                            ; get virtual address of SAC area at start of page
+            mr         r8,r3                                           ; save virtual address
+            lwz                r5,SACvrswap+0(r7)                      ; get 64-bit converter from V to R
+            lwz                r6,SACvrswap+4(r7)                      ; both halves, though only bottom used on 32-bit machine
+#if FPVECDBG
+                       lis             r0,HIGH_ADDR(CutTrace)          ; (TEST/DEBUG)
+                       li              r2,0x2204                                       ; (TEST/DEBUG)
+                       oris    r0,r0,LOW_ADDR(CutTrace)        ; (TEST/DEBUG) 
+                       sc                                                                      ; (TEST/DEBUG) 
+#endif
+            bl         saveSetup                                       ; turn translation off, 64-bit on, load many regs
+            bf++       31,svrt3                                        ; skip if not save_ret_wMSR
+            mr         r11,r4                                          ; was save_ret_wMSR, so overwrite saved MSR
+svrt3:
+            bf--       pf64Bitb,svrt4                          ; skip if a 32-bit processor
+            
+            ; Handle 64-bit processor.
+            
+            rldimi     r6,r5,32,0                                      ; merge upper and lower halves of SACvrswap together
+            xor                r3,r8,r6                                        ; get r3 <- 64-bit physical address of this savearea
+            bl         saveRet64                                       ; return it
+            mtlr       r9                                                      ; restore return address
+            b          saveRestore64                           ; restore MSR
+            
+            ; Handle 32-bit processor.
+            
+svrt4:
+            xor                r3,r8,r6                                        ; get r3 <- 32-bit physical address of this savearea
+            bl         saveRet32                                       ; return it
+            mtlr       r9                                                      ; restore return address
+            b          saveRestore32                           ; restore MSR
 
+/*
+ * *****************************
+ * * s a v e _ r e t _ p h y s *
+ * *****************************
+ *
+ *     void    save_ret_phys(reg64_t);
+ *
+ *                     Called from lowmem vectors to return (ie, free) a savearea by physical address.
+ *                     Translation and interrupts are already off, and 64-bit mode is set if defined.
+ *                     We can take _no_ exceptions of any kind in this code, including PTE miss, since
+ *                     that would result in a deadlock.  We expect:
+ *                             r3 = phys addr of savearea
+ *                        msr = IR, DR, and EE off, SF on
+ *             cr6 = pf64Bit flag
+ *                     We destroy:
+ *                             r0,r2-r10.
+ */
                        .align  5
                        .globl  EXT(save_ret_phys)
 
 LEXT(save_ret_phys)
+            mfsprg     r10,0                                           ; get the per-proc ptr
+            bf--       pf64Bitb,saveRet32                      ; handle 32-bit machine
+            b          saveRet64                                       ; handle 64-bit machine
+            
 
-                       mfsprg  r9,0                                            ; Get the per proc
-                       crset   cr1_eq                                          ; Clear CR1_ne to indicate we have physical address
-                       mr              r8,r3                                           ; Save the savearea address
-
-                       nop
-
-srcommon:      
+/*
+ * *********************
+ * * s a v e R e t 6 4 *
+ * *********************
+ *
+ *                     This is the internal routine to free a savearea, passed by 64-bit physical
+ *                     address.  We assume that IR, DR, and EE are all off, that SF is on, and:
+ *                             r3 = phys address of the savearea
+ *                        r10 = per-proc ptr
+ *                     We destroy:
+ *                             r0,r2-r8.
+ */
+            .align     5
+ saveRet64:
                        li              r0,SAVempty                                     ; Get marker for free savearea
-                       lwz             r7,lclfreecnt(r9)                       ; Get the local count
-                       lwz             r6,lclfree(r9)                          ; Get the old local header
+                       lwz             r7,lclfreecnt(r10)                      ; Get the local count
+                       ld              r6,lclfree(r10)                         ; Get the old local header
                        addi    r7,r7,1                                         ; Pop up the free count
-                       stw             r6,SAVprev(r8)                          ; Plant free chain pointer
+                       std             r6,SAVprev(r3)                          ; Plant free chain pointer
                        cmplwi  r7,LocalSaveMax                         ; Has the list gotten too long?
-                       stb             r0,SAVflags+2(r8)                       ; Mark savearea free
-                       stw             r8,lclfree(r9)                          ; Chain us on in
-                       stw             r7,lclfreecnt(r9)                       ; Bump up the count
-                       bgt-    srtrim                                          ; List is too long, go trim it...
-                       
-                       btlr    cr1_eq                                          ; Leave if we were a physical request...
+                       stb             r0,SAVflags+2(r3)                       ; Mark savearea free
+                       std             r3,lclfree(r10)                         ; Chain us on in
+                       stw             r7,lclfreecnt(r10)                      ; Bump up the count
+                       bltlr++                                                         ; List not too long, so done
                        
-                       mtmsr   r12                                                     ; Restore translation and exceptions
-                       isync                                                           ; Make sure about it
-       
-#if FPVECDBG
-                       lis             r0,HIGH_ADDR(CutTrace)          ; (TEST/DEBUG)
-                       li              r2,0x2204                                       ; (TEST/DEBUG)
-                       mr              r3,r8                                           ; (TEST/DEBUG)
-                       oris    r0,r0,LOW_ADDR(CutTrace)        ; (TEST/DEBUG) 
-                       sc                                                                      ; (TEST/DEBUG) 
-#endif
-                       blr                                                                     ; Leave...
-
-;
-;                      The local savearea chain has gotten too long.  Trim it down to the target.
-;                      Note: never trim the first one, just skip over it.
-;
-
-                       .align  5
+/*                     The local savearea chain has gotten too long.  Trim it down to the target.
+ *                     Here's a tricky bit, and important:
+ *
+ *                     When we trim the list, we NEVER trim the very first one.  This is because that is
+ *                     the very last one released and the exception exit code will release the savearea
+ *                     BEFORE it is done using it. Wouldn't be too good if another processor started
+ *                     using it, eh?  So for this case, we are safe so long as the savearea stays on
+ *                     the local list.  (Note: the exit routine needs to do this because it is in the 
+ *                     process of restoring all context and it needs to keep it until the last second.)
+ */
 
-srtrim:                
-                       mr              r2,r8                                           ; Save the guy we are releasing
-                       lwz             r8,SAVprev(r8)                          ; Skip over the first
+            mflr       r0                                                      ; save return to caller of saveRet64
+                       mr              r2,r3                                           ; r2 <- 1st one on local list, which must not be trimmed
+                       ld              r3,SAVprev(r3)                          ; Skip over the first
                        subi    r7,r7,LocalSaveTarget           ; Figure out how much to trim   
-                       mr              r6,r8                                           ; Save the first one to trim
+                       mr              r6,r3                                           ; r6 <- first one to trim
                        mr              r5,r7                                           ; Save the number we are trimming
                        
-srtrimming:    addic.  r7,r7,-1                                        ; Any left to do?
-                       ble-    srtrimmed                                       ; Nope...
-                       lwz             r8,SAVprev(r8)                          ; Skip to the next one
-                       b               srtrimming                                      ; Keep going...
+saveRet64a:
+            addic.     r7,r7,-1                                        ; Any left to do?
+                       ble--   saveRet64b                                      ; Nope...
+                       ld              r3,SAVprev(r3)                          ; Skip to the next one
+                       b               saveRet64a                                      ; Keep going...
                        
-                       .align  5
-
-srtrimmed:     lis             r10,hi16(EXT(saveanchor))       ; Get the high part of the anchor       
-                       lwz             r7,SAVprev(r8)                          ; Point to the next one
-                       ori             r10,r10,lo16(EXT(saveanchor))   ; Bottom half of the anchor 
+saveRet64b:                                                                            ; r3 <- last one to trim
+                       ld              r7,SAVprev(r3)                          ; Point to the first one not to trim
                        li              r4,LocalSaveTarget                      ; Set the target count
-                       stw             r7,SAVprev(r2)                          ; Trim stuff leaving the one just released as first
-                       stw             r4,lclfreecnt(r9)                       ; Set the current count
+                       std             r7,SAVprev(r2)                          ; Trim stuff leaving the one just released as first
+                       stw             r4,lclfreecnt(r10)                      ; Set the current count
                        
-                       mflr    r9                                                      ; Save the return
                        bl              savelock                                        ; Lock up the anchor
                        
-                       lwz             r3,SVfree(r10)                          ; Get the old head of the free list
-                       lwz             r4,SVfreecnt(r10)                       ; Get the number of free ones
-                       lwz             r7,SVinuse(r10)                         ; Get the number that are in use
-                       stw             r6,SVfree(r10)                          ; Point to the first trimmed savearea
+                       ld              r8,SVfree(0)                            ; Get the old head of the free list
+                       lwz             r4,SVfreecnt(0)                         ; Get the number of free ones
+                       lwz             r7,SVinuse(0)                           ; Get the number that are in use
+                       std             r6,SVfree(0)                            ; Point to the first trimmed savearea
                        add             r4,r4,r5                                        ; Add number trimmed to free count
-                       stw             r3,SAVprev(r8)                          ; Chain the old head to the tail of the trimmed guys
+                       std             r8,SAVprev(r3)                          ; Chain the old head to the tail of the trimmed guys
                        sub             r7,r7,r5                                        ; Remove the trims from the in use count
-                       stw             r4,SVfreecnt(r10)                       ; Set new free count
-                       stw             r7,SVinuse(r10)                         ; Set new in use count
-
-                       bl              saveunlock                                      ; Set adjust count and unlock the saveanchor
+                       stw             r4,SVfreecnt(0)                         ; Set new free count
+                       stw             r7,SVinuse(0)                           ; Set new in use count
 
-                       mtlr    r9                                                      ; Restore the return
+                       mtlr    r0                                                      ; Restore the return to our caller
+                       b               saveunlock                                      ; Set adjust count, unlock the saveanchor, and return
+            
 
-                       btlr+   cr1_eq                                          ; Leave if we were a physical request...
+/*
+ * *********************
+ * * s a v e R e t 3 2 *
+ * *********************
+ *
+ *                     This is the internal routine to free a savearea, passed by 32-bit physical
+ *                     address.  We assume that IR, DR, and EE are all off, and:
+ *                             r3 = phys address of the savearea
+ *                        r10 = per-proc ptr
+ *                     We destroy:
+ *                             r0,r2-r8.
+ */
+            .align     5
+ saveRet32:
+                       li              r0,SAVempty                                     ; Get marker for free savearea
+                       lwz             r7,lclfreecnt(r10)                      ; Get the local count
+                       lwz             r6,lclfree+4(r10)                       ; Get the old local header
+                       addi    r7,r7,1                                         ; Pop up the free count
+                       stw             r6,SAVprev+4(r3)                        ; Plant free chain pointer
+                       cmplwi  r7,LocalSaveMax                         ; Has the list gotten too long?
+                       stb             r0,SAVflags+2(r3)                       ; Mark savearea free
+                       stw             r3,lclfree+4(r10)                       ; Chain us on in
+                       stw             r7,lclfreecnt(r10)                      ; Bump up the count
+                       bltlr+                                                          ; List not too long, so done
                        
-                       mtmsr   r12                                                     ; Restore translation and exceptions
-                       isync                                                           ; Make sure about it
-       
-#if FPVECDBG
-                       lis             r0,HIGH_ADDR(CutTrace)          ; (TEST/DEBUG)
-                       mr              r3,r2                                           ; (TEST/DEBUG)
-                       li              r2,0x2205                                       ; (TEST/DEBUG)
-                       oris    r0,r0,LOW_ADDR(CutTrace)        ; (TEST/DEBUG) 
-                       sc                                                                      ; (TEST/DEBUG) 
-#endif
-                       blr                                                                     ; Leave...
-
+/*                     The local savearea chain has gotten too long.  Trim it down to the target.
+ *                     Here's a tricky bit, and important:
+ *
+ *                     When we trim the list, we NEVER trim the very first one.  This is because that is
+ *                     the very last one released and the exception exit code will release the savearea
+ *                     BEFORE it is done using it. Wouldn't be too good if another processor started
+ *                     using it, eh?  So for this case, we are safe so long as the savearea stays on
+ *                     the local list.  (Note: the exit routine needs to do this because it is in the 
+ *                     process of restoring all context and it needs to keep it until the last second.)
+ */
 
-;
-;                      NOTE: This is the most complicated part of savearea maintainence. 
-;                            Expect errors here.......
-;
-;                      save_trim_free - this routine will trim the free list down to the target count.
-;                      It trims the list and, if the pool page was fully allocated, puts that page on 
-;                      the start of the pool list.
-;
-;                      If the savearea being released is the last on a pool page (i.e., all entries
-;                      are released), the page is dequeued from the pool and queued to any other 
-;                      found during this scan.  Note that this queue is maintained virtually.
-;
-;                      When the scan is done, the saveanchor lock is released and the list of
-;                      freed pool pages is returned.
+            mflr       r0                                                      ; save return to caller of saveRet32
+                       mr              r2,r3                                           ; r2 <- 1st one on local list, which must not be trimmed
+                       lwz             r3,SAVprev+4(r3)                        ; Skip over the first
+                       subi    r7,r7,LocalSaveTarget           ; Figure out how much to trim   
+                       mr              r6,r3                                           ; r6 <- first one to trim
+                       mr              r5,r7                                           ; Save the number we are trimming
+                       
+saveRet32a:
+            addic.     r7,r7,-1                                        ; Any left to do?
+                       ble-    saveRet32b                                      ; Nope...
+                       lwz             r3,SAVprev+4(r3)                        ; Skip to the next one
+                       b               saveRet32a                                      ; Keep going...
+                       
+saveRet32b:                                                                            ; r3 <- last one to trim
+                       lwz             r7,SAVprev+4(r3)                        ; Point to the first one not to trim
+                       li              r4,LocalSaveTarget                      ; Set the target count
+                       stw             r7,SAVprev+4(r2)                        ; Trim stuff leaving the one just released as first
+                       stw             r4,lclfreecnt(r10)                      ; Set the current count
+                       
+                       bl              savelock                                        ; Lock up the anchor
+                       
+                       lwz             r8,SVfree+4(0)                          ; Get the old head of the free list
+                       lwz             r4,SVfreecnt(0)                         ; Get the number of free ones
+                       lwz             r7,SVinuse(0)                           ; Get the number that are in use
+                       stw             r6,SVfree+4(0)                          ; Point to the first trimmed savearea
+                       add             r4,r4,r5                                        ; Add number trimmed to free count
+                       stw             r8,SAVprev+4(r3)                        ; Chain the old head to the tail of the trimmed guys
+                       sub             r7,r7,r5                                        ; Remove the trims from the in use count
+                       stw             r4,SVfreecnt(0)                         ; Set new free count
+                       stw             r7,SVinuse(0)                           ; Set new in use count
 
+                       mtlr    r0                                                      ; Restore the return to our caller
+                       b               saveunlock                                      ; Set adjust count, unlock the saveanchor, and return
 
-;                      For latency sake we may want to revisit this code. If we are trimming a
-;                      large number of saveareas, we could be disabled and holding the savearea lock
-;                      for quite a while.  It may be that we want to break the trim down into parts.
-;                      Possibly trimming the free list, then individually pushing them into the free pool.
-;
-;                      This function expects to be called with translation on and a valid stack.
-;
 
+/*
+ * *******************************
+ * * s a v e _ t r i m _ f r e e *
+ * *******************************
+ *
+ *     struct savearea_comm    *save_trim_free(void);
+ *
+ *                     Trim the free list down to the target count, ie by -(SVadjust) save areas.
+ *                     It trims the list and, if a pool page was fully allocated, puts that page on 
+ *                     the start of the pool list.
+ *
+ *                     If the savearea being released is the last on a pool page (i.e., all entries
+ *                     are released), the page is dequeued from the pool and queued to any other 
+ *                     found during this scan.  Note that this queue is maintained virtually.
+ *
+ *                     When the scan is done, the saveanchor lock is released and the list of
+ *                     freed pool pages is returned to our caller.
+ *
+ *                     For latency sake we may want to revisit this code. If we are trimming a
+ *                     large number of saveareas, we could be disabled and holding the savearea lock
+ *                     for quite a while.  It may be that we want to break the trim down into parts.
+ *                     Possibly trimming the free list, then individually pushing them into the free pool.
+ *
+ *                     This function expects to be called with translation on and a valid stack.
+ *                     It uses the standard ABI, ie we destroy r2 and r3-r11, and return the ptr in r3.
+ */
                        .align  5
                        .globl  EXT(save_trim_free)
 
 LEXT(save_trim_free)
 
                        subi    r1,r1,(FM_ALIGN(16)+FM_SIZE)    ; Make space for 4 registers on stack
-                       mfsprg  r9,2                                            ; Get the feature flags
+            mflr       r9                                                      ; save our return address
                        stw             r28,FM_SIZE+0(r1)                       ; Save R28
-                       mfmsr   r12                                                     ; Get the MSR 
-                       rlwinm  r12,r12,0,MSR_FP_BIT+1,MSR_FP_BIT-1     ; Force floating point off
-                       rlwinm  r12,r12,0,MSR_VEC_BIT+1,MSR_VEC_BIT-1   ; Force vectors off
-                       stw             r29,FM_SIZE+4(r1)                       ; Save R28
-                       mtcrf   0x04,r9                                         ; Set the features                      
-                       stw             r30,FM_SIZE+8(r1)                       ; Save R28
-                       lis             r10,hi16(EXT(saveanchor))       ; Get the high part of the anchor       
-                       stw             r31,FM_SIZE+12(r1)                      ; Save R28
-                       andi.   r3,r12,0x7FCF                           ; Turn off all translation and rupts
-                       ori             r10,r10,lo16(EXT(saveanchor))   ; Bottom half of the anchor 
-                       mflr    r9                                                      ; Save the return
-
-                       bt              pfNoMSRirb,stNoMSR                      ; No MSR...
-
-                       mtmsr   r3                                                      ; Translation and all off
-                       isync                                                           ; Toss prefetch
-                       b               stNoMSRx
-                       
-                       .align  5
-                       
-stNoMSR:       li              r0,loadMSR                                      ; Get the MSR setter SC
-                       sc                                                                      ; Set it
-                       
-stNoMSRx:      bl              savelock                                        ; Go lock up the anchor
+                       stw             r29,FM_SIZE+4(r1)                       ; Save R29
+                       stw             r30,FM_SIZE+8(r1)                       ; Save R30
+                       stw             r31,FM_SIZE+12(r1)                      ; Save R31
+
+            bl         saveSetup                                       ; turn off translation and interrupts, load many regs
+            bl         savelock                                        ; Go lock up the anchor
 
-                       lwz             r8,SVadjust(r10)                        ; How many do we need to clear out?
+                       lwz             r8,SVadjust(0)                          ; How many do we need to clear out?
                        li              r3,0                                            ; Get a 0
                        neg.    r8,r8                                           ; Get the actual we need to toss (adjust is neg if too many)
-                       lwz             r7,SVfree(r10)                          ; Get the first on the free list
-                       bgt+    stneedtrim                                      ; Yeah, we still need it...
-                       
-                       mtlr    r9                                                      ; Restore return
-                       stw             r3,SVlock(r10)                          ; Quick unlock (no need for sync or to set adjust, nothing changed)
+            ble-       save_trim_free1                         ; skip if no trimming needed anymore
+            bf--       pf64Bitb,saveTrim32                     ; handle 32-bit processors
+            b          saveTrim64                                      ; handle 64-bit processors
 
-                       mtmsr   r12                                                     ; Restore translation and exceptions
-                       isync                                                           ; Make sure about it
+save_trim_free1:                                                               ; by the time we were called, no need to trim anymore                   
+                       stw             r3,SVlock(0)                            ; Quick unlock (no need for sync or to set adjust, nothing changed)
+                       mtlr    r9                                                      ; Restore return
        
 #if FPVECDBG
                        lis             r0,HIGH_ADDR(CutTrace)          ; (TEST/DEBUG)
@@ -609,34 +834,42 @@ stNoMSRx: bl              savelock                                        ; Go lock up the anchor
                        oris    r0,r0,LOW_ADDR(CutTrace)        ; (TEST/DEBUG) 
                        sc                                                                      ; (TEST/DEBUG) 
 #endif
-                       addi    r1,r1,(FM_ALIGN(16)+FM_SIZE)    ; Pop stack - have not trashed register so no need to reload
-                       blr                                                                     ; Leave...
+                       addi    r1,r1,(FM_ALIGN(16)+FM_SIZE); Pop stack - have not trashed register so no need to reload
+                       b               saveRestore                                     ; restore translation and EE, turn SF off, return to our caller
 
-                       .align  5
-                       
-stneedtrim:    mr              r6,r7                                           ; Save the first one 
+
+/*
+ * ***********************
+ * * s a v e T r i m 3 2 *
+ * ***********************
+ *
+ *     Handle "save_trim_free" on 32-bit processors.  At this point, translation and interrupts
+ *  are off, the savearea anchor is locked, and:
+ *              r8 = #pages to trim (>0)
+ *          r9 = return address
+ *             r10 = per-proc ptr
+ *             r11 = MSR at entry
+ */
+
+saveTrim32:    
+                       lwz             r7,SVfree+4(0)                          ; Get the first on the free list
+            mr         r6,r7                                           ; Save the first one 
                        mr              r5,r8                                           ; Save the number we are trimming
                        
-                       nop
-                       nop
-                       
 sttrimming:    addic.  r5,r5,-1                                        ; Any left to do?
                        ble-    sttrimmed                                       ; Nope...
-                       lwz             r7,SAVprev(r7)                          ; Skip to the next one
+                       lwz             r7,SAVprev+4(r7)                        ; Skip to the next one
                        b               sttrimming                                      ; Keep going...
-                       
-                       .align  5
 
-sttrimmed:     lwz             r5,SAVprev(r7)                          ; Get the next one (for new head of free list)
-                       lwz             r4,SVfreecnt(r10)                       ; Get the free count
-                       stw             r5,SVfree(r10)                          ; Set new head
+sttrimmed:     lwz             r5,SAVprev+4(r7)                        ; Get the next one (for new head of free list)
+                       lwz             r4,SVfreecnt(0)                         ; Get the free count
+                       stw             r5,SVfree+4(0)                          ; Set new head
                        sub             r4,r4,r8                                        ; Calculate the new free count
                        li              r31,0                                           ; Show we have no free pool blocks yet
-                       cmplwi  cr1,r5,0                                        ; Make sure this is not equal
-                       stw             r4,SVfreecnt(r10)                       ; Set new free count
+                       crclr   cr1_eq                                          ; dont exit loop before 1st iteration
+                       stw             r4,SVfreecnt(0)                         ; Set new free count
                        lis             r30,hi16(sac_empty)                     ; Get what empty looks like
                        
-;
 ;                      NOTE: The savearea size must be 640 (0x280).  We are doing a divide by shifts and stuff
 ;                      here.
 ;
@@ -644,6 +877,17 @@ sttrimmed: lwz             r5,SAVprev(r7)                          ; Get the next one (for new head of free list)
 #error Savearea size is not 640!!!!!!!!!!!!
 #endif
 
+            ; Loop over each savearea we are trimming.
+            ;   r6 = next savearea to trim
+            ;   r7 = last savearea to trim
+            ;   r8 = #pages to trim (>0)
+            ;    r9 = return address
+            ;  r10 = per-proc ptr
+            ;  r11 = MSR at entry
+            ;  r30 = what SACalloc looks like when all saveareas are free
+            ;  r31 = free pool block list
+            ;  cr1 = beq set if we just trimmed the last, ie if we are done
+
 sttoss:                beq+    cr1,stdone                                      ; All done now...
 
                        cmplw   cr1,r6,r7                                       ; Have we finished the loop?
@@ -661,7 +905,7 @@ sttoss:             beq+    cr1,stdone                                      ; All done now...
                        srw             r4,r4,r0                                        ; Get the allocation mask
                        or              r5,r5,r4                                        ; Free this entry
                        cmplw   r5,r4                                           ; Is this the only free entry?
-                       lwz             r6,SAVprev(r6)                          ; Chain to the next trimmed savearea
+                       lwz             r6,SAVprev+4(r6)                        ; Chain to the next trimmed savearea
                        cmplw   cr7,r30,r5                                      ; Does this look empty?
                        stw             r5,SACalloc(r2)                         ; Save back the allocation bits
                        beq-    stputpool                                       ; First free entry, go put it into the pool...
@@ -673,19 +917,19 @@ sttoss:           beq+    cr1,stdone                                      ; All done now...
                        
                        lwz             r29,SACflags(r2)                        ; Get the flags
                        cmplwi  cr5,r31,0                                       ; Is this guy on the release list?
-                       lwz             r28,SACnext(r2)                         ; Get the forward chain
+                       lwz             r28,SACnext+4(r2)                       ; Get the forward chain
 
                        rlwinm. r0,r29,0,sac_permb,sac_permb    ; Is this a permanently allocated area? (also sets 0 needed below)
                        bne-    sttoss                                          ; This is permanent entry, do not try to release...
 
-                       lwz             r29,SACprev(r2)                         ; and the previous
+                       lwz             r29,SACprev+4(r2)                       ; and the previous
                        beq-    cr5,stnot1st                            ; Not first
-                       lwz             r0,SACvrswap(r31)                       ; Load the previous pool page vr conversion
+                       lwz             r0,SACvrswap+4(r31)                     ; Load the previous pool page vr conversion
                        
-stnot1st:      stw             r28,SACnext(r29)                        ; Previous guy points to my next
+stnot1st:      stw             r28,SACnext+4(r29)                      ; Previous guy points to my next
                        xor             r0,r0,r31                                       ; Make the last guy virtual
-                       stw             r29,SACprev(r28)                        ; Next guy points back to my previous                   
-                       stw             r0,SAVprev(r2)                          ; Store the old top virtual as my back chain
+                       stw             r29,SACprev+4(r28)                      ; Next guy points back to my previous                   
+                       stw             r0,SAVprev+4(r2)                        ; Store the old top virtual as my back chain
                        mr              r31,r2                                          ; My physical is now the head of the chain
                        b               sttoss                                          ; Get the next one...
                        
@@ -693,31 +937,136 @@ stnot1st:        stw             r28,SACnext(r29)                        ; Previous guy points to my next
 ;                      A pool block that had no free entries now has one.  Stick it on the pool list.
 ;
                        
-                       .align  5
-                       
-stputpool:     lwz             r28,SVpoolfwd(r10)                      ; Get the first guy on the list
-                       stw             r2,SVpoolfwd(r10)                       ; Put us on the top of the list
-                       stw             r28,SACnext(r2)                         ; We point to the old top
-                       stw             r2,SACprev(r28)                         ; Old top guy points back to us
-                       stw             r10,SACprev(r2)                         ; Our back points to the anchor
+stputpool:     lwz             r28,SVpoolfwd+4(0)                      ; Get the first guy on the list
+                       li              r0,saveanchor                           ; Point to the saveanchor
+                       stw             r2,SVpoolfwd+4(0)                       ; Put us on the top of the list
+                       stw             r28,SACnext+4(r2)                       ; We point to the old top
+                       stw             r2,SACprev+4(r28)                       ; Old top guy points back to us
+                       stw             r0,SACprev+4(r2)                        ; Our back points to the anchor
                        b               sttoss                                          ; Go on to the next one...
+
+
+/*
+ * ***********************
+ * * s a v e T r i m 6 4 *
+ * ***********************
+ *
+ *     Handle "save_trim_free" on 64-bit processors.  At this point, translation and interrupts
+ *  are off, SF is on, the savearea anchor is locked, and:
+ *              r8 = #pages to trim (>0)
+ *          r9 = return address
+ *             r10 = per-proc ptr
+ *             r11 = MSR at entry
+ */
+
+saveTrim64:    
+                       ld              r7,SVfree(0)                            ; Get the first on the free list
+            mr         r6,r7                                           ; Save the first one 
+                       mr              r5,r8                                           ; Save the number we are trimming
                        
-;
-;                      We are all done.  Relocate pool release head, restore all, and go.
-;                      
+sttrimming64:  
+            addic.     r5,r5,-1                                        ; Any left to do?
+                       ble--   sttrimmed64                                     ; Nope...
+                       ld              r7,SAVprev(r7)                          ; Skip to the next one
+                       b               sttrimming64                            ; Keep going...
 
-                       .align  5
+sttrimmed64:
+            ld         r5,SAVprev(r7)                          ; Get the next one (for new head of free list)
+                       lwz             r4,SVfreecnt(0)                         ; Get the free count
+                       std             r5,SVfree(0)                            ; Set new head
+                       sub             r4,r4,r8                                        ; Calculate the new free count
+                       li              r31,0                                           ; Show we have no free pool blocks yet
+                       crclr   cr1_eq                                          ; dont exit loop before 1st iteration
+                       stw             r4,SVfreecnt(0)                         ; Set new free count
+                       lis             r30,hi16(sac_empty)                     ; Get what empty looks like
                        
+
+            ; Loop over each savearea we are trimming.
+            ;   r6 = next savearea to trim
+            ;   r7 = last savearea to trim
+            ;   r8 = #pages to trim (>0)
+            ;    r9 = return address
+            ;  r10 = per-proc ptr
+            ;  r11 = MSR at entry
+            ;  r30 = what SACalloc looks like when all saveareas are free
+            ;  r31 = free pool block list
+            ;  cr1 = beq set if we just trimmed the last, ie if we are done
+            ;
+            ; WARNING: as in the 32-bit path, this code is doing a divide by 640 (SAVsize).
+
+sttoss64:
+            beq++      cr1,stdone                                      ; All done now...
+
+                       cmpld   cr1,r6,r7                                       ; Have we finished the loop?
+
+                       lis             r0,0x0044                                       ; Get top of table      
+                       rldicr  r2,r6,0,51                                      ; r2 <- phys addr of savearea block (with control area)
+                       ori             r0,r0,0x2200                            ; Finish shift table
+                       rlwinm  r4,r6,25,27,30                          ; Get (addr >> 7) & 0x1E (same as twice high nybble)
+                       lwz             r5,SACalloc(r2)                         ; Get the allocation bits
+                       addi    r4,r4,1                                         ; Shift 1 extra
+                       rlwinm  r3,r6,25,31,31                          ; Get (addr >> 7) & 1
+                       rlwnm   r0,r0,r4,29,31                          ; Get partial index
+                       lis             r4,lo16(0x8000)                         ; Get the bit mask
+                       add             r0,r0,r3                                        ; Make the real index
+                       srw             r4,r4,r0                                        ; Get the allocation mask
+                       or              r5,r5,r4                                        ; Free this entry
+                       cmplw   r5,r4                                           ; Is this the only free entry?
+                       ld              r6,SAVprev(r6)                          ; Chain to the next trimmed savearea
+                       cmplw   cr7,r30,r5                                      ; Does this look empty?
+                       stw             r5,SACalloc(r2)                         ; Save back the allocation bits
+                       beq--   stputpool64                                     ; First free entry, go put it into the pool...
+                       bne++   cr7,sttoss64                            ; Not an empty block
+                       
+;                      We have an empty block.  Remove it from the pool list.
+                       
+                       lwz             r29,SACflags(r2)                        ; Get the flags
+                       cmpldi  cr5,r31,0                                       ; Is this guy on the release list?
+                       ld              r28,SACnext(r2)                         ; Get the forward chain
+
+                       rlwinm. r0,r29,0,sac_permb,sac_permb    ; Is this a permanently allocated area? (also sets 0 needed below)
+                       bne--   sttoss64                                        ; This is permanent entry, do not try to release...
+
+                       ld              r29,SACprev(r2)                         ; and the previous
+                       beq--   cr5,stnot1st64                          ; Not first
+                       ld              r0,SACvrswap(r31)                       ; Load the previous pool page vr conversion
+                       
+stnot1st64:    
+            std                r28,SACnext(r29)                        ; Previous guy points to my next
+                       xor             r0,r0,r31                                       ; Make the last guy virtual
+                       std             r29,SACprev(r28)                        ; Next guy points back to my previous                   
+                       std             r0,SAVprev(r2)                          ; Store the old top virtual as my back chain
+                       mr              r31,r2                                          ; My physical is now the head of the chain
+                       b               sttoss64                                        ; Get the next one...
+                       
+;                      A pool block that had no free entries now has one.  Stick it on the pool list.
+                       
+stputpool64:
+            ld         r28,SVpoolfwd(0)                        ; Get the first guy on the list
+                       li              r0,saveanchor                           ; Point to the saveanchor
+                       std             r2,SVpoolfwd(0)                         ; Put us on the top of the list
+                       std             r28,SACnext(r2)                         ; We point to the old top
+                       std             r2,SACprev(r28)                         ; Old top guy points back to us
+                       std             r0,SACprev(r2)                          ; Our back points to the anchor
+                       b               sttoss64                                        ; Go on to the next one...
+                       
+
+;                      We are all done.  Relocate pool release head, restore all, and go.  This code
+;                      is used both by the 32 and 64-bit paths.
+;                               r9 = return address
+;                              r10 = per-proc ptr
+;                              r11 = MSR at entry
+;                              r31 = free pool block list
+
 stdone:                bl              saveunlock                                      ; Unlock the saveanchor and set adjust field
 
                        mr.             r3,r31                                          ; Move release chain and see if there are any
                        li              r5,0                                            ; Assume either V=R or no release chain
                        beq-    stnorel                                         ; Nothing to release...
-                       lwz             r5,SACvrswap(r31)                       ; Get the vr conversion
-
-stnorel:       mtmsr   r12                                                     ; Restore translation and exceptions
-                       isync                                                           ; Make sure about it
+                       lwz             r5,SACvrswap+4(r31)                     ; Get the vr conversion (only need low half if 64-bit)
 
+stnorel:       
+            bl         saveRestore                                     ; restore translation and exceptions, turn off SF
                        mtlr    r9                                                      ; Restore the return
                        
                        lwz             r28,FM_SIZE+0(r1)                       ; Restore R28
@@ -726,6 +1075,7 @@ stnorel:   mtmsr   r12                                                     ; Restore translation and exceptions
                        lwz             r31,FM_SIZE+12(r1)                      ; Restore R31
                        addi    r1,r1,(FM_ALIGN(16)+FM_SIZE)    ; Pop the stack
                        xor             r3,r3,r5                                        ; Convert release chain address to virtual
+            rlwinm     r3,r3,0,0,31                            ; if 64-bit, clear upper half of virtual address
                                                        
 #if FPVECDBG
                        lis             r0,HIGH_ADDR(CutTrace)          ; (TEST/DEBUG)
@@ -734,70 +1084,69 @@ stnorel: mtmsr   r12                                                     ; Restore translation and exceptions
                        sc                                                                      ; (TEST/DEBUG) 
 #endif
                        blr                                                                     ; Return...
-                       
-;
-;                      save_recover - here we scan the free pool and see if we can get
-;                      enough free saveareas to hit target.
-;
-;                      If we empty a pool block, remove it from the pool list
-;
-;
+            
+            
+/*
+ * ***************************
+ * * s a v e _ r e c o v e r *
+ * ***************************
+ *
+ *     int save_recover(void);
+ *
+ *     Returns nonzero if we can get enough saveareas to hit the target.  We scan the free
+ *     pool.  If we empty a pool block, we remove it from the pool list.
+ */                    
                        
                        .align  5
                        .globl  EXT(save_recover)
 
 LEXT(save_recover)
-                       mfsprg  r9,2                                            ; Get the feature flags
-                       mfmsr   r12                                                     ; Get the MSR 
-                       rlwinm  r12,r12,0,MSR_FP_BIT+1,MSR_FP_BIT-1     ; Force floating point off
-                       rlwinm  r12,r12,0,MSR_VEC_BIT+1,MSR_VEC_BIT-1   ; Force vectors off
-                       mtcrf   0x04,r9                                         ; Set the features                      
-                       lis             r10,hi16(EXT(saveanchor))       ; Get the high part of the anchor       
-                       andi.   r3,r12,0x7FCF                           ; Turn off all translation and rupts
-                       ori             r10,r10,lo16(EXT(saveanchor))   ; Bottom half of the anchor 
-                       mflr    r9                                                      ; Save the return
-
-                       bt              pfNoMSRirb,srcNoMSR                     ; No MSR...
-
-                       mtmsr   r3                                                      ; Translation and all off
-                       isync                                                           ; Toss prefetch
-                       b               srcNoMSRx
-                       
-                       .align  5
-                       
-srcNoMSR:      li              r0,loadMSR                                      ; Get the MSR setter SC
-                       sc                                                                      ; Set it
-                       
-srcNoMSRx:     bl              savelock                                        ; Go lock up the anchor
+            mflr       r9                                                      ; save return address
+            bl         saveSetup                                       ; turn translation and interrupts off, SF on, load many regs
+            bl         savelock                                        ; lock the savearea anchor
 
-                       lwz             r8,SVadjust(r10)                        ; How many do we need to clear get?
+                       lwz             r8,SVadjust(0)                          ; How many do we need to clear get?
                        li              r3,0                                            ; Get a 0
                        mr.             r8,r8                                           ; Do we need any?
-                       bgt+    srcneedmore                                     ; Yeah, we still need it...
-                       
+            ble--      save_recover1                           ; not any more
+            bf--       pf64Bitb,saveRecover32          ; handle 32-bit processor
+            b          saveRecover64                           ; handle 64-bit processor
+            
+save_recover1:                                                                 ; by the time we locked the anchor, no longer short
                        mtlr    r9                                                      ; Restore return
-                       stw             r3,SVlock(r10)                          ; Quick unlock (no need for sync or to set adjust, nothing changed)
-
-                       mtmsr   r12                                                     ; Restore translation and exceptions
-                       isync                                                           ; Make sure about it
-       
+                       stw             r3,SVlock(0)                            ; Quick unlock (no need for sync or to set adjust, nothing changed)
 #if FPVECDBG
                        lis             r0,HIGH_ADDR(CutTrace)          ; (TEST/DEBUG)
                        li              r2,0x2208                                       ; (TEST/DEBUG)
                        oris    r0,r0,LOW_ADDR(CutTrace)        ; (TEST/DEBUG) 
                        sc                                                                      ; (TEST/DEBUG) 
 #endif
-                       blr                                                                     ; Leave...
+                       b               saveRestore                                     ; turn translation etc back on, return to our caller
 
-                       .align  5
-       
-srcneedmore:
-                       mr              r6,r10                                          ; Start at pool anchor
-                       cmplwi  cr1,r10,0                                       ; Make sure we start as not equal                                       
-                       lwz             r7,SVfreecnt(r10)                       ; Get the current free count
-                       
-srcnpool:      lwz             r6,SACnext(r6)                          ; Point to the next one
-                       cmplw   r6,r10                                          ; Have we wrapped?
+
+/*
+ * *****************************
+ * * s a v e R e c o v e r 3 2 *
+ * *****************************
+ *
+ *     Handle "save_recover" on 32-bit processors.  At this point, translation and interrupts
+ *  are off, the savearea anchor is locked, and:
+ *              r8 = #pages to recover
+ *          r9 = return address
+ *             r10 = per-proc ptr
+ *             r11 = MSR at entry
+ */
+
+saveRecover32:
+                       li              r6,saveanchor                           ; Start at pool anchor
+                       crclr   cr1_eq                                          ; initialize the loop test                                      
+                       lwz             r7,SVfreecnt(0)                         ; Get the current free count
+
+
+; Loop over next block in free pool.  r6 is the ptr to the last block we looked at.
+
+srcnpool:      lwz             r6,SACnext+4(r6)                        ; Point to the next one
+                       cmplwi  r6,saveanchor                           ; Have we wrapped?
                        beq-    srcdone                                         ; Yes, did not have enough...
                        
                        lwz             r5,SACalloc(r6)                         ; Pick up the allocation for this pool block
@@ -810,6 +1159,16 @@ srcnpool: lwz             r6,SACnext(r6)                          ; Point to the next one
 #error Savearea size is not 640!!!!!!!!!!!!
 #endif
 
+; Loop over free savearea in current block.
+;               r5 = bitmap of free saveareas in block at r6 (ie, SACalloc)
+;               r6 = ptr to current free pool block
+;               r7 = free count
+;               r8 = #pages more we still need to recover
+;           r9 = return address
+;              r10 = per-proc ptr
+;              r11 = MSR at entry
+;              cr1 = beq if (r8==0)
+
 srcnext:       beq-    cr1,srcdone                                     ; We have no more to get...
 
                        lis             r3,0x8000                                       ; Get the top bit on
@@ -825,130 +1184,273 @@ srcnext:       beq-    cr1,srcdone                                     ; We have no more to get...
                        stw             r5,SACalloc(r6)                         ; Set new allocation bits
                        
                        add             r2,r2,r6                                        ; Get the actual address of the savearea
-                       lwz             r3,SVfree(r10)                          ; Get the head of the chain
+                       lwz             r3,SVfree+4(0)                          ; Get the head of the chain
                        cmplwi  cr1,r8,0                                        ; Do we actually need any more?
-                       stw             r2,SVfree(r10)                          ; Push ourselves in the front
-                       stw             r3,SAVprev(r2)                          ; Chain the rest of the list behind 
+                       stw             r2,SVfree+4(0)                          ; Push ourselves in the front
+                       stw             r3,SAVprev+4(r2)                        ; Chain the rest of the list behind 
                        
                        bne+    srcnext                                         ; The pool block is not empty yet, try for another...
                        
-                       lwz             r2,SACnext(r6)                          ; Get the next pointer
-                       lwz             r3,SACprev(r6)                          ; Get the previous pointer
-                       stw             r3,SACprev(r2)                          ; The previous of my next points to my previous
-                       stw             r2,SACnext(r3)                          ; The next of my previous points to my next
+                       lwz             r2,SACnext+4(r6)                        ; Get the next pointer
+                       lwz             r3,SACprev+4(r6)                        ; Get the previous pointer
+                       stw             r3,SACprev+4(r2)                        ; The previous of my next points to my previous
+                       stw             r2,SACnext+4(r3)                        ; The next of my previous points to my next
                        bne+    cr1,srcnpool                            ; We still have more to do...
-                       
-srcdone:       stw             r7,SVfreecnt(r10)                       ; Set the new free count
+
+
+; Join here from 64-bit path when we have recovered all the saveareas we need to.
+
+srcdone:       stw             r7,SVfreecnt(0)                         ; Set the new free count
                        bl              saveunlock                                      ; Unlock the save and set adjust field
 
                        mtlr    r9                                                      ; Restore the return
-                       mtmsr   r12                                                     ; Restore translation and exceptions
-                       isync                                                           ; Make sure about it
-       
 #if FPVECDBG
                        lis             r0,HIGH_ADDR(CutTrace)          ; (TEST/DEBUG)
                        li              r2,0x2209                                       ; (TEST/DEBUG)
                        oris    r0,r0,LOW_ADDR(CutTrace)        ; (TEST/DEBUG) 
                        sc                                                                      ; (TEST/DEBUG) 
 #endif
-                       blr                                                                     ; Leave...
+                       b               saveRestore                                     ; turn xlate and EE back on, SF off, and return to our caller
+
+
+/*
+ * *****************************
+ * * s a v e R e c o v e r 6 4 *
+ * *****************************
+ *
+ *     Handle "save_recover" on 64-bit processors.  At this point, translation and interrupts
+ *  are off, the savearea anchor is locked, and:
+ *              r8 = #pages to recover
+ *          r9 = return address
+ *             r10 = per-proc ptr
+ *             r11 = MSR at entry
+ */
+
+saveRecover64:
+                       li              r6,saveanchor                           ; Start at pool anchor
+                       crclr   cr1_eq                                          ; initialize the loop test                                      
+                       lwz             r7,SVfreecnt(0)                         ; Get the current free count
+
+
+; Loop over next block in free pool.  r6 is the ptr to the last block we looked at.
+
+srcnpool64:    
+            ld         r6,SACnext(r6)                          ; Point to the next one
+                       cmpldi  r6,saveanchor                           ; Have we wrapped?
+                       beq--   srcdone                                         ; Yes, did not have enough...
                        
+                       lwz             r5,SACalloc(r6)                         ; Pick up the allocation for this pool block
+                       
+
+; Loop over free savearea in current block.
+;               r5 = bitmap of free saveareas in block at r6 (ie, SACalloc)
+;               r6 = ptr to current free pool block
+;               r7 = free count
+;               r8 = #pages more we still need to recover
+;           r9 = return address
+;              r10 = per-proc ptr
+;              r11 = MSR at entry
+;              cr1 = beq if (r8==0)
 ;
-;                      Here is where we lock the saveanchor lock
-;                      We assume R10 points to the saveanchor
-;                      We trash R7 and R3
-;
+; WARNING: as in the 32-bit path, we depend on (SAVsize==640)
 
-                       .align  5
-       
-savelock:      lwarx   r7,0,r10                                        ; Grab the lock value 
-                       li              r3,1                                            ; Use part of the delay time 
-                       mr.             r7,r7                                           ; Is it locked? */
-                       bne-    sllcks                                          ; Yeah, wait for it to clear...
-                       stwcx.  r3,0,r10                                        ; Try to seize that there durn lock
-                       beq+    sllckd                                          ; Got it...
-                       b               savelock                                        ; Collision, try again...
+srcnext64:     
+            beq--      cr1,srcdone                                     ; We have no more to get...
 
-                       .align  5
+                       lis             r3,0x8000                                       ; Get the top bit on
+                       cntlzw  r4,r5                                           ; Find a free slot
+                       addi    r7,r7,1                                         ; Bump up the free count
+                       srw             r3,r3,r4                                        ; Make a mask
+                       slwi    r0,r4,7                                         ; First multiply by 128
+                       subi    r8,r8,1                                         ; Decrement the need count
+                       slwi    r2,r4,9                                         ; Then multiply by 512
+                       andc.   r5,r5,r3                                        ; Clear out the "free" bit
+                       add             r2,r2,r0                                        ; Sum to multiply by 640        
                        
-sllcks:                lwz             r7,SVlock(r10)                          ; Get that lock in here
-                       mr.             r7,r7                                           ; Is it free yet?
-                       beq+    savelock                                        ; Yeah, try for it again...
-                       b               sllcks                                          ; Sniff away...
+                       stw             r5,SACalloc(r6)                         ; Set new allocation bits
+                       
+                       add             r2,r2,r6                                        ; Get the actual address of the savearea
+                       ld              r3,SVfree(0)                            ; Get the head of the chain
+                       cmplwi  cr1,r8,0                                        ; Do we actually need any more?
+                       std             r2,SVfree(0)                            ; Push ourselves in the front
+                       std             r3,SAVprev(r2)                          ; Chain the rest of the list behind 
                        
-                       nop                                                                     ; Force isync to last in ifetch buffer
-                       nop
-                       nop
+                       bne++   srcnext64                                       ; The pool block is not empty yet, try for another...
                        
-sllckd:                isync                                                           ; Make sure translation is off
-                       blr                                                                     ; Return....
-
+                       ld              r2,SACnext(r6)                          ; Get the next pointer
+                       ld              r3,SACprev(r6)                          ; Get the previous pointer
+                       std             r3,SACprev(r2)                          ; The previous of my next points to my previous
+                       std             r2,SACnext(r3)                          ; The next of my previous points to my next
+                       bne++   cr1,srcnpool64                          ; We still have more to do...
+            
+            b          srcdone
 
-;
-;                      This is the common routine that sets the saveadjust field and unlocks the savearea 
-;                      anchor.
-;                      
-;                      Note that we can not use R9 here because we use it to save the LR across the call.
-;                      Also, R10 is assumed to point to the saveanchor. R3 is also reserved.
-;
 
+/* 
+ * *******************
+ * * s a v e l o c k *
+ * *******************
+ *
+ *                     Lock the savearea anchor, so we can manipulate the free list.
+ *              msr = interrupts and translation off
+ *                     We destroy:
+ *                             r8, r3, r12
+ */                    
                        .align  5
 
+savelock:      lwz             r8,SVlock(0)                            ; See if lock is held
+            cmpwi      r8,0
+                       li              r12,saveanchor                          ; Point to the saveanchor
+                       bne--   savelock                                        ; loop until lock released...
+               
+savelock0:     lwarx   r8,0,r12                                        ; Grab the lock value 
+                       cmpwi   r8,0                                            ; taken?
+            li         r8,1                                            ; get nonzero to lock it with
+                       bne--   savelock1                                       ; already locked, wait for it to clear...
+                       stwcx.  r8,0,r12                                        ; Try to seize that there durn lock
+            isync                                                              ; assume we got it
+            beqlr++                                                            ; reservation not lost, so we have the lock
+                       b               savelock0                                       ; Try again...
+                       
+savelock1:     li              r8,lgKillResv                           ; Point to killing field
+                       stwcx.  r8,0,r8                                         ; Kill reservation
+                       b               savelock                                        ; Start over....
+               
+
+/*
+ * ***********************
+ * * s a v e u n l o c k *
+ * ***********************
+ *
+ *
+ *                     This is the common routine that sets the saveadjust field and unlocks the savearea 
+ *                     anchor.
+ *                             msr = interrupts and translation off
+ *                     We destroy:
+ *                             r2, r5, r6, r8.
+ */
+                       .align  5
 saveunlock:
-                       lwz             r6,SVfreecnt(r10)                       ; and the number on the free list
-                       lwz             r5,SVinuse(r10)                         ; Pick up the in use count
-                       cmplwi  r6,FreeListMin                          ; Do we have at least the minimum?
-                       blt-    sutooshort                                      ; Do not have minumum....
-                       lwz             r7,SVtarget(r10)                        ; Get the target
+                       lwz             r6,SVfreecnt(0)                         ; and the number on the free list
+                       lwz             r5,SVinuse(0)                           ; Pick up the in use count
+            subic.     r8,r6,FreeListMin                       ; do we have at least the minimum?
+                       lwz             r2,SVtarget(0)                          ; Get the target
+            neg                r8,r8                                           ; assuming we are short, get r8 <- shortfall
+            blt--      saveunlock1                                     ; skip if fewer than minimum on free list
                        
                        add             r6,r6,r5                                        ; Get the total number of saveareas
-                       addi    r5,r7,-SaveLowHysteresis        ; Find bottom
+                       addi    r5,r2,-SaveLowHysteresis        ; Find low end of acceptible range
                        sub             r5,r6,r5                                        ; Make everything below hysteresis negative
-                       sub             r7,r7,r6                                        ; Get the distance from the target
-                       rlwinm  r5,r5,0,0,31                            ; Clear negative bit
+                       sub             r2,r2,r6                                        ; Get the distance from the target
                        addi    r5,r5,-(SaveLowHysteresis + SaveHighHysteresis + 1)     ; Subtract full hysteresis range
                        srawi   r5,r5,31                                        ; Get 0xFFFFFFFF if outside range or 0 if inside
-                       and             r7,r7,r5                                        ; Get 0 if in range or distance to target if not
+                       and             r8,r2,r5                                        ; r8 <- 0 if in range or distance to target if not
 
-                       li              r8,0                                            ; Set a clear value
-                       stw             r7,SVadjust(r10)                        ; Set the adjustment value                      
-
-                       sync                                                            ; Make sure everything is done
-                       stw             r8,SVlock(r10)                          ; Unlock the savearea chain 
+saveunlock1:
+                       li              r5,0                                            ; Set a clear value
+                       stw             r8,SVadjust(0)                          ; Set the adjustment value                      
+                       eieio                                                           ; Make sure everything is done
+                       stw             r5,SVlock(0)                            ; Unlock the savearea chain 
                        blr
-                       
-                       .align  5
-                       
-sutooshort:    subfic  r6,r6,FreeListMin                       ; Get the number needed to hit minimum
-                       li              r8,0                                            ; Set a clear value
-                       stw             r6,SVadjust(r10)                        ; Set the adjustment value                      
-
-                       sync                                                            ; Make sure everything is done
-                       stw             r8,SVlock(r10)                          ; Unlock the savearea chain 
-                       blr
-
-
 
 
 /*
- *                     struct savearea *save_cpv(struct savearea *);    Converts a physical savearea address to virtual
+ * *******************
+ * * s a v e _ c p v *
+ * *******************
+ *
+ *     struct savearea *save_cpv(addr64_t saveAreaPhysAddr);
+ *
+ *          Converts a physical savearea address to virtual.  Called with translation on
+ *                     and in 32-bit mode.  Note that the argument is passed as a long long in (r3,r4).
  */
 
                        .align  5
                        .globl  EXT(save_cpv)
 
 LEXT(save_cpv)
+            mflr       r9                                                      ; save return address
+            mr         r8,r3                                           ; save upper half of phys address here
+            bl         saveSetup                                       ; turn off translation and interrupts, turn SF on
+                       rlwinm  r5,r4,0,0,19                            ; Round back to the start of the physical savearea block
+            bf--       pf64Bitb,save_cpv1                      ; skip if 32-bit processor
+            rldimi     r5,r8,32,0                                      ; r5 <- 64-bit phys address of block
+save_cpv1:
+                       lwz             r6,SACvrswap+4(r5)                      ; Get the conversion to virtual (only need low half if 64-bit)
+            mtlr       r9                                                      ; restore return address
+            xor                r3,r4,r6                                        ; convert phys to virtual
+            rlwinm     r3,r3,0,0,31                            ; if 64-bit, zero upper half of virtual address
+            b          saveRestore                                     ; turn translation etc back on, SF off, and return r3
+                               
                        
-                       mfmsr   r10                                                     ; Get the current MSR
-                       rlwinm  r10,r10,0,MSR_FP_BIT+1,MSR_FP_BIT-1     ; Force floating point off
-                       rlwinm  r10,r10,0,MSR_VEC_BIT+1,MSR_VEC_BIT-1   ; Force vectors off
-                       rlwinm  r4,r3,0,0,19                            ; Round back to the start of the physical savearea block
-                       andi.   r9,r10,0x7FEF                           ; Turn off interrupts and data translation
-                       mtmsr   r9                                                      ; Disable DR and EE
-                       isync
-                       
-                       lwz             r4,SACvrswap(r4)                        ; Get the conversion to virtual
-                       mtmsr   r10                                                     ; Interrupts and DR back on
-                       isync
-                       xor             r3,r3,r4                                        ; Convert to physical
-                       blr
+/*
+ * *********************
+ * * s a v e S e t u p *
+ * *********************
+ *
+ * This routine is called at the start of all the save-area subroutines.
+ * It turns off translation, disabled interrupts, turns on 64-bit mode,
+ * and sets up cr6 with the feature flags (especially pf64Bit).
+ * 
+ * Note that most save-area routines cannot take _any_ interrupt (such as a
+ * PTE miss) once the savearea anchor is locked, since that would result in
+ * instant deadlock as we need a save-area to process any exception.
+ * We set up:
+ *             r10 = per-proc ptr
+ *             r11 = old MSR
+ *             cr5 = pfNoMSRir feature flag
+ *             cr6 = pf64Bit   feature flag
+ *
+ * We use r0, r3, r10, and r11.
+ */
+saveSetup:
+            mfmsr      r11                                                     ; get msr
+                       mfsprg  r3,2                                            ; get feature flags
+                       li              r0,0
+            mtcrf      0x2,r3                                          ; copy pf64Bit to cr6
+            ori                r0,r0,lo16(MASK(MSR_IR)+MASK(MSR_DR)+MASK(MSR_EE))
+            mtcrf      0x4,r3                                          ; copy pfNoMSRir to cr5
+            andc       r3,r11,r0                                       ; turn off IR, DR, and EE
+            li         r0,1                                            ; get a 1 in case its a 64-bit machine
+            bf--       pf64Bitb,saveSetup1                     ; skip if not a 64-bit machine
+                       rldimi  r3,r0,63,MSR_SF_BIT                     ; turn SF (bit 0) on
+            mtmsrd     r3                                                      ; turn translation and interrupts off, 64-bit mode on
+            isync                                                              ; wait for it to happen
+            mfsprg     r10,0                                           ; get per-proc ptr
+            blr
+saveSetup1:                                                                            ; here on 32-bit machines
+            bt-                pfNoMSRirb,saveSetup2           ; skip if cannot turn off IR with a mtmsr
+            mtmsr      r3                                                      ; turn translation and interrupts off
+            isync                                                              ; wait for it to happen
+            mfsprg     r10,0                                           ; get per-proc ptr
+            blr
+saveSetup2:                                                                            ; here if pfNoMSRir set for this machine
+            li         r0,loadMSR                                      ; we will "mtmsr r3" via system call
+            sc
+            mfsprg     r10,0                                           ; get per-proc ptr
+            blr
+        
+                       
+/*
+ * *************************
+ * * s a v e R e s t o r e *
+ * *************************
+ *
+ * Undoes the effect of calling "saveSetup", ie it turns relocation and interrupts back on,
+ * and turns 64-bit mode back off.
+ *             r11 = old MSR
+ *             cr6 = pf64Bit   feature flag
+ */
+saveRestore:
+            bt++       pf64Bitb,saveRestore64          ; handle a 64-bit processor
+saveRestore32:
+            mtmsr      r11                                                     ; restore MSR
+            isync                                                              ; wait for translation to start up
+            blr
+saveRestore64:                                                                 ; 64-bit processor
+            mtmsrd     r11                                                     ; restore MSR
+            isync                                                              ; wait for changes to happen
+            blr
+