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1/*
2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
7 *
8 * This file contains Original Code and/or Modifications of Original Code
9 * as defined in and that are subject to the Apple Public Source License
10 * Version 2.0 (the 'License'). You may not use this file except in
11 * compliance with the License. Please obtain a copy of the License at
12 * http://www.opensource.apple.com/apsl/ and read it before using this
13 * file.
14 *
15 * The Original Code and all software distributed under the License are
16 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
17 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
18 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
20 * Please see the License for the specific language governing rights and
21 * limitations under the License.
22 *
23 * @APPLE_LICENSE_HEADER_END@
24 */
25#include <ppc/asm.h>
26#include <ppc/proc_reg.h>
27#include <cpus.h>
28#include <assym.s>
29#include <debug.h>
30#include <mach/ppc/vm_param.h>
31#include <ppc/exception.h>
32
33
34/*
35 * The compiler generates calls to this function and passes address
36 * of caller of the function [ from which mcount is called ] as the
37 * first parameter.
38 * mcount disables interrupts prior to call mcount() and restores
39 * interrupt upon return.
40 * To prevent recursive calls to mcount(), a flag, mcountOff, is set
41 * in cpu_flags per_proc.
42 */
43
44 .align 4
45 .globl mcount
46mcount:
47 mflr r0 ; Load lr
48 stw r0,8(r1) ; Save lr on the stack
49 stwu r1,-64(r1) ; Get a stack frame
50 mfmsr r9 ; Get msr
51 rlwinm r9,r9,0,MSR_FP_BIT+1,MSR_FP_BIT-1 ; Force floating point off
52 rlwinm r9,r9,0,MSR_VEC_BIT+1,MSR_VEC_BIT-1 ; Force vectors off
53 rlwinm r8,r9,0,MSR_EE_BIT+1,MSR_EE_BIT-1 ; Turn off interruptions
54 mtmsr r8 ; Update msr
55 isync
56 mfsprg r7,0 ; Get per_proc
57 lhz r6,PP_CPU_FLAGS(r7) ; Get cpu flags
58 ori r5,r6,mcountOff ;
59 cmplw r5,r6 ; is mount off
60 beq mcount_ret ; return if off
61 sth r5,PP_CPU_FLAGS(r7) ; Update cpu_flags
62 stw r9,FM_ARG0(r1) ; Save MSR
63 mr r4, r0
64 bl _mcount ; Call the C routine
65 lwz r9,FM_ARG0(r1)
66 mfsprg r7,0 ; Get per-proc block
67 lhz r6,PP_CPU_FLAGS(r7) ; Get CPU number
68 li r5,mcountOff ;
69 andc r6,r6,r5 ; Clear mcount_off
70 sth r6,PP_CPU_FLAGS(r7) ; Save cpu_flags
71mcount_ret:
72 addi r1,r1,64
73 mtmsr r9 ; Restore MSR
74 lwz r0,8(r1)
75 mtlr r0
76 blr
77