osfmk/ppc/db_asm.s

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * @OSF_COPYRIGHT@
  24  */
  25
  26 #include <debug.h>
  27 #include <ppc/asm.h>
  28 #include <ppc/proc_reg.h>
  29 #include <mach/ppc/vm_param.h>
  30 #include <assym.s>
  31
  32
  33 /* void
  34  * db_phys_cmp(src_a, src_b, bytecount)
  35  *      vm_offset_t     src_a;
  36  *      vm_offset_t     src_b;
  37  *      int             bytecount
  38  *
  39  * This routine will compare bytecount bytes from physical address src_a and physical
  40  * address src_b.
  41  */
  42
  43 #warning THIS IS BROKEN FOR 64-BIT
  44
  45         /* Switch off data translations */
  46         lis             r7,hi16(MASK(MSR_VEC))
  47         ori             r7,r7,lo16(MASK(MSR_FP))
  48         mfmsr   r6
  49         andc    r6,r6,r7                        ; Force FP and vec off
  50         ori             r7,r7,lo16(MASK(MSR_DR))        ; Set the DR bit
  51         andc    r7,r6,r7                        ; Force DR off
  52         mtmsr   r7
  53         isync                   /* Ensure data translations are off */
  54
  55         subi    r3,     r3,     4
  56         subi    r4,     r4,     4
  57
  58         cmpwi   r5,     3
  59         ble-    .L_db_phys_cmp_bytes
  60 .L_db_phys_cmp_loop:
  61         lwz     r0,     4(r3)
  62         lwz     r7,     4(r4)
  63         addi    r3,     r3,     4
  64         addi    r4,     r4,     4
  65         subi    r5,     r5,     4
  66         cmpw    r0,     r7
  67         bne     .L_db_phys_cmp_false
  68         cmpwi   r5,     3
  69         bgt+    .L_db_phys_cmp_loop
  70
  71         /* If no leftover bytes, we're done now */
  72         cmpwi   r5,     0
  73         beq+    .L_db_phys_cmp_true
  74
  75 .L_db_phys_cmp_bytes:
  76         addi    r3,     r3,     3
  77         addi    r4,     r4,     3
  78 .L_db_phys_cmp_byte_loop:
  79         lbz     r0,     1(r3)
  80         lbz     r7,     1(r4)
  81         addi    r3,     r3,     1
  82         addi    r4,     r4,     1
  83         subi    r5,     r5,     1
  84         cmpw    r0,     r7
  85         bne     .L_db_phys_cmp_false
  86         cmpwi   r5,     0
  87         bne+    .L_db_phys_cmp_loop
  88
  89 .L_db_phys_cmp_true:
  90         li      r3,     1
  91         b       .L_db_phys_cmp_done
  92
  93 .L_db_phys_cmp_false:
  94         li      r3,     0
  95
  96 .L_db_phys_cmp_done:
  97         mtmsr   r6              /* Restore original translations */
  98         isync                   /* Ensure data translations are off */
  99
 100         blr
 101