osfmk/ppc/db_asm.s

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_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. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31
  32 #include <debug.h>
  33 #include <ppc/asm.h>
  34 #include <ppc/proc_reg.h>
  35 #include <mach/ppc/vm_param.h>
  36 #include <assym.s>
  37
  38
  39 /* void
  40  * db_phys_cmp(src_a, src_b, bytecount)
  41  *      vm_offset_t     src_a;
  42  *      vm_offset_t     src_b;
  43  *      int             bytecount
  44  *
  45  * This routine will compare bytecount bytes from physical address src_a and physical
  46  * address src_b.
  47  */
  48
  49 #warning THIS IS BROKEN FOR 64-BIT
  50
  51         /* Switch off data translations */
  52         lis             r7,hi16(MASK(MSR_VEC))
  53         ori             r7,r7,lo16(MASK(MSR_FP))
  54         mfmsr   r6
  55         andc    r6,r6,r7                        ; Force FP and vec off
  56         ori             r7,r7,lo16(MASK(MSR_DR))        ; Set the DR bit
  57         andc    r7,r6,r7                        ; Force DR off
  58         mtmsr   r7
  59         isync                   /* Ensure data translations are off */
  60
  61         subi    r3,     r3,     4
  62         subi    r4,     r4,     4
  63
  64         cmpwi   r5,     3
  65         ble-    .L_db_phys_cmp_bytes
  66 .L_db_phys_cmp_loop:
  67         lwz     r0,     4(r3)
  68         lwz     r7,     4(r4)
  69         addi    r3,     r3,     4
  70         addi    r4,     r4,     4
  71         subi    r5,     r5,     4
  72         cmpw    r0,     r7
  73         bne     .L_db_phys_cmp_false
  74         cmpwi   r5,     3
  75         bgt+    .L_db_phys_cmp_loop
  76
  77         /* If no leftover bytes, we're done now */
  78         cmpwi   r5,     0
  79         beq+    .L_db_phys_cmp_true
  80
  81 .L_db_phys_cmp_bytes:
  82         addi    r3,     r3,     3
  83         addi    r4,     r4,     3
  84 .L_db_phys_cmp_byte_loop:
  85         lbz     r0,     1(r3)
  86         lbz     r7,     1(r4)
  87         addi    r3,     r3,     1
  88         addi    r4,     r4,     1
  89         subi    r5,     r5,     1
  90         cmpw    r0,     r7
  91         bne     .L_db_phys_cmp_false
  92         cmpwi   r5,     0
  93         bne+    .L_db_phys_cmp_loop
  94
  95 .L_db_phys_cmp_true:
  96         li      r3,     1
  97         b       .L_db_phys_cmp_done
  98
  99 .L_db_phys_cmp_false:
 100         li      r3,     0
 101
 102 .L_db_phys_cmp_done:
 103         mtmsr   r6              /* Restore original translations */
 104         isync                   /* Ensure data translations are off */
 105
 106         blr
 107