xnu-517.9.5.tar.gz

[apple/xnu.git] / iokit / IOKit / ppc / IOSharedLockImp.h

diff --git a/iokit/IOKit/ppc/IOSharedLockImp.h b/iokit/IOKit/ppc/IOSharedLockImp.h
index f320f9d335c6839052bc85f60dc36f11c32abdf9..53c3a98cd511b6d2fc867f13ec631921971bcb6d 100644 (file)
--- a/iokit/IOKit/ppc/IOSharedLockImp.h
+++ b/iokit/IOKit/ppc/IOSharedLockImp.h
@@ -49,14 +49,35 @@
 #define _IOKIT_IOSHAREDLOCKIMP_H
 
 #include <architecture/ppc/asm_help.h>
+#ifdef KERNEL
+#undef END
+#include <mach/ppc/asm.h>
+#endif
 
-// 'Till we're building in kernel
 .macro DISABLE_PREEMPTION
 #ifdef KERNEL
+       stwu    r1,-(FM_SIZE)(r1)
+       mflr    r0
+       stw             r3,FM_ARG0(r1)
+       stw             r0,(FM_SIZE+FM_LR_SAVE)(r1)
+       bl              EXT(_disable_preemption)
+       lwz             r3,FM_ARG0(r1)
+       lwz             r1,0(r1)
+       lwz             r0,FM_LR_SAVE(r1)
+       mtlr    r0
 #endif
 .endmacro
 .macro ENABLE_PREEMPTION
 #ifdef KERNEL
+       stwu    r1,-(FM_SIZE)(r1)
+       mflr    r0
+       stw             r3,FM_ARG0(r1)
+       stw             r0,(FM_SIZE+FM_LR_SAVE)(r1)
+       bl              EXT(_enable_preemption)
+       lwz             r3,FM_ARG0(r1)
+       lwz             r1,0(r1)
+       lwz             r0,FM_LR_SAVE(r1)
+       mtlr    r0
 #endif
 .endmacro
 
@@ -72,20 +93,48 @@
 
 #ifndef KERNEL
 LEAF(_ev_lock)
-LEAF(_IOSpinLock)
-       li      a6,1            // lock value
-       lwarx   a7,0,a0         // CEMV10
-9:
-       sync
-       lwarx   a7,0,a0         // read the lock
-       cmpwi   cr0,a7,0        // is it busy?
-       bne-    9b              // yes, spin
-       sync
-       stwcx.  a6,0,a0         // try to get the lock
-       bne-    9b              // failed, try again
-       isync
-       blr                     // got it, return
+
+               li              a6,1                    // lock value
+               
+8:             lwz             a7,0(a0)                // Get lock word
+               mr.             a7,a7                   // Is it held?
+               bne--   8b                              // Yup...
+
+9:             lwarx   a7,0,a0                 // read the lock
+               mr.             a7,a7                   // Is it held?
+               bne--   7f                              // yes, kill reservation
+               stwcx.  a6,0,a0                 // try to get the lock
+               bne--   9b                              // failed, try again
+               isync
+               blr                                             // got it, return
+               
+7:             li              a7,-4                   // Point to a spot in the red zone
+               stwcx.  a7,a7,r1                // Kill reservation
+               b               8b                              // Go wait some more...
+               
+               
 END(_ev_lock)
+
+LEAF(_IOSpinLock)
+
+               li              a6,1                    // lock value
+               
+8:             lwz             a7,0(a0)                // Get lock word
+               mr.             a7,a7                   // Is it held?
+               bne--   8b                              // Yup...
+
+9:             lwarx   a7,0,a0                 // read the lock
+               mr.             a7,a7                   // Is it held?
+               bne--   7f                              // yes, kill reservation
+               stwcx.  a6,0,a0                 // try to get the lock
+               bne--   9b                              // failed, try again
+               isync
+               blr                                             // got it, return
+               
+7:             li              a7,-4                   // Point to a spot in the red zone
+               stwcx.  a7,a7,r1                // Kill reservation
+               b               8b                              // Go wait some more...
+END(_IOSpinLock)
 #endif
 
 /*
@@ -97,7 +146,6 @@ END(_ev_lock)
  */
 
 LEAF(_ev_unlock)
-LEAF(_IOSpinUnlock)
        sync
        li      a7,0
        stw     a7,0(a0)
@@ -105,6 +153,14 @@ LEAF(_IOSpinUnlock)
        blr
 END(_ev_unlock)
 
+LEAF(_IOSpinUnlock)
+       sync
+       li      a7,0
+       stw     a7,0(a0)
+       ENABLE_PREEMPTION()
+       blr
+END(_IOSpinUnlock)
+
 
 /*
  *     ev_try_lock(p)
@@ -114,25 +170,61 @@ END(_ev_unlock)
  */
 
 LEAF(_ev_try_lock)
-LEAF(_IOTrySpinLock)
-       li      a6,1            // lock value
-        DISABLE_PREEMPTION()
-       lwarx   a7,0,a0         // CEMV10
-8:
-       sync
-       lwarx   a7,0,a0         // read the lock
-       cmpwi   cr0,a7,0        // is it busy?
-       bne-    9f              // yes, give up
-       sync
-       stwcx.  a6,0,a0         // try to get the lock
-       bne-    8b              // failed, try again
-       li      a0,1            // return TRUE
-       isync
-       blr
-9:
-       ENABLE_PREEMPTION()
-       li      a0,0            // return FALSE
-       blr
+       
+               DISABLE_PREEMPTION()
+
+               li              a6,1                    // lock value
+               
+               lwz             a7,0(a0)                // Get lock word
+               mr.             a7,a7                   // Is it held?
+               bne--   6f                              // Yup...
+
+9:             lwarx   a7,0,a0                 // read the lock
+               mr.             a7,a7                   // Is it held?
+               bne--   7f                              // yes, kill reservation
+               stwcx.  a6,0,a0                 // try to get the lock
+               bne--   9b                              // failed, try again
+               li              a0,1                    // return TRUE
+               isync
+               blr                                             // got it, return
+               
+7:             li              a7,-4                   // Point to a spot in the red zone
+               stwcx.  a7,a7,r1                // Kill reservation
+
+6:
+               ENABLE_PREEMPTION()
+               li      a0,0                            // return FALSE
+               blr
+               
 END(_ev_try_lock)
 
+LEAF(_IOTrySpinLock)
+       
+               DISABLE_PREEMPTION()
+
+               li              a6,1                    // lock value
+               
+               lwz             a7,0(a0)                // Get lock word
+               mr.             a7,a7                   // Is it held?
+               bne--   6f                              // Yup...
+
+9:             lwarx   a7,0,a0                 // read the lock
+               mr.             a7,a7                   // Is it held?
+               bne--   7f                              // yes, kill reservation
+               stwcx.  a6,0,a0                 // try to get the lock
+               bne--   9b                              // failed, try again
+               li              a0,1                    // return TRUE
+               isync
+               blr                                             // got it, return
+               
+7:             li              a7,-4                   // Point to a spot in the red zone
+               stwcx.  a7,a7,r1                // Kill reservation
+
+6:
+               ENABLE_PREEMPTION()
+               li      a0,0                            // return FALSE
+               blr
+               
+END(_IOTrySpinLock)
+
 #endif /* ! _IOKIT_IOSHAREDLOCKIMP_H */