osfmk/ppc/db_asm.s

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 /*
  24  * @OSF_COPYRIGHT@
  25  */
  26
  27 #include <debug.h>
  28 #include <ppc/asm.h>
  29 #include <ppc/proc_reg.h>
  30 #include <mach/ppc/vm_param.h>
  31 #include <assym.s>
  32
  33
  34 /* void
  35  * db_phys_cmp(src_a, src_b, bytecount)
  36  *      vm_offset_t     src_a;
  37  *      vm_offset_t     src_b;
  38  *      int             bytecount
  39  *
  40  * This routine will compare bytecount bytes from physical address src_a and physical
  41  * address src_b.
  42  */
  43
  44 #warning THIS IS BROKEN FOR 64-BIT
  45
  46         /* Switch off data translations */
  47         lis             r7,hi16(MASK(MSR_VEC))
  48         ori             r7,r7,lo16(MASK(MSR_FP))
  49         mfmsr   r6
  50         andc    r6,r6,r7                        ; Force FP and vec off
  51         ori             r7,r7,lo16(MASK(MSR_DR))        ; Set the DR bit
  52         andc    r7,r6,r7                        ; Force DR off
  53         mtmsr   r7
  54         isync                   /* Ensure data translations are off */
  55
  56         subi    r3,     r3,     4
  57         subi    r4,     r4,     4
  58
  59         cmpwi   r5,     3
  60         ble-    .L_db_phys_cmp_bytes
  61 .L_db_phys_cmp_loop:
  62         lwz     r0,     4(r3)
  63         lwz     r7,     4(r4)
  64         addi    r3,     r3,     4
  65         addi    r4,     r4,     4
  66         subi    r5,     r5,     4
  67         cmpw    r0,     r7
  68         bne     .L_db_phys_cmp_false
  69         cmpwi   r5,     3
  70         bgt+    .L_db_phys_cmp_loop
  71
  72         /* If no leftover bytes, we're done now */
  73         cmpwi   r5,     0
  74         beq+    .L_db_phys_cmp_true
  75
  76 .L_db_phys_cmp_bytes:
  77         addi    r3,     r3,     3
  78         addi    r4,     r4,     3
  79 .L_db_phys_cmp_byte_loop:
  80         lbz     r0,     1(r3)
  81         lbz     r7,     1(r4)
  82         addi    r3,     r3,     1
  83         addi    r4,     r4,     1
  84         subi    r5,     r5,     1
  85         cmpw    r0,     r7
  86         bne     .L_db_phys_cmp_false
  87         cmpwi   r5,     0
  88         bne+    .L_db_phys_cmp_loop
  89
  90 .L_db_phys_cmp_true:
  91         li      r3,     1
  92         b       .L_db_phys_cmp_done
  93
  94 .L_db_phys_cmp_false:
  95         li      r3,     0
  96
  97 .L_db_phys_cmp_done:
  98         mtmsr   r6              /* Restore original translations */
  99         isync                   /* Ensure data translations are off */
 100
 101         blr
 102