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-rw-r--r--arch/powerpc/kernel/pmc.c112
1 files changed, 112 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/pmc.c b/arch/powerpc/kernel/pmc.c
new file mode 100644
index 000000000000..2d333cc84082
--- /dev/null
+++ b/arch/powerpc/kernel/pmc.c
@@ -0,0 +1,112 @@
1/*
2 * arch/powerpc/kernel/pmc.c
3 *
4 * Copyright (C) 2004 David Gibson, IBM Corporation.
5 * Includes code formerly from arch/ppc/kernel/perfmon.c:
6 * Author: Andy Fleming
7 * Copyright (c) 2004 Freescale Semiconductor, Inc
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 */
14
15#include <linux/config.h>
16#include <linux/errno.h>
17#include <linux/spinlock.h>
18#include <linux/module.h>
19
20#include <asm/processor.h>
21#include <asm/pmc.h>
22
23#if defined(CONFIG_FSL_BOOKE) && !defined(CONFIG_E200)
24static void dummy_perf(struct pt_regs *regs)
25{
26 unsigned int pmgc0 = mfpmr(PMRN_PMGC0);
27
28 pmgc0 &= ~PMGC0_PMIE;
29 mtpmr(PMRN_PMGC0, pmgc0);
30}
31#elif defined(CONFIG_PPC64) || defined(CONFIG_6xx)
32
33#ifndef MMCR0_PMAO
34#define MMCR0_PMAO 0
35#endif
36
37/* Ensure exceptions are disabled */
38static void dummy_perf(struct pt_regs *regs)
39{
40 unsigned int mmcr0 = mfspr(SPRN_MMCR0);
41
42 mmcr0 &= ~(MMCR0_PMXE|MMCR0_PMAO);
43 mtspr(SPRN_MMCR0, mmcr0);
44}
45#else
46static void dummy_perf(struct pt_regs *regs)
47{
48}
49#endif
50
51static DEFINE_SPINLOCK(pmc_owner_lock);
52static void *pmc_owner_caller; /* mostly for debugging */
53perf_irq_t perf_irq = dummy_perf;
54
55int reserve_pmc_hardware(perf_irq_t new_perf_irq)
56{
57 int err = 0;
58
59 spin_lock(&pmc_owner_lock);
60
61 if (pmc_owner_caller) {
62 printk(KERN_WARNING "reserve_pmc_hardware: "
63 "PMC hardware busy (reserved by caller %p)\n",
64 pmc_owner_caller);
65 err = -EBUSY;
66 goto out;
67 }
68
69 pmc_owner_caller = __builtin_return_address(0);
70 perf_irq = new_perf_irq ? : dummy_perf;
71
72 out:
73 spin_unlock(&pmc_owner_lock);
74 return err;
75}
76EXPORT_SYMBOL_GPL(reserve_pmc_hardware);
77
78void release_pmc_hardware(void)
79{
80 spin_lock(&pmc_owner_lock);
81
82 WARN_ON(! pmc_owner_caller);
83
84 pmc_owner_caller = NULL;
85 perf_irq = dummy_perf;
86
87 spin_unlock(&pmc_owner_lock);
88}
89EXPORT_SYMBOL_GPL(release_pmc_hardware);
90
91#ifdef CONFIG_PPC64
92void power4_enable_pmcs(void)
93{
94 unsigned long hid0;
95
96 hid0 = mfspr(SPRN_HID0);
97 hid0 |= 1UL << (63 - 20);
98
99 /* POWER4 requires the following sequence */
100 asm volatile(
101 "sync\n"
102 "mtspr %1, %0\n"
103 "mfspr %0, %1\n"
104 "mfspr %0, %1\n"
105 "mfspr %0, %1\n"
106 "mfspr %0, %1\n"
107 "mfspr %0, %1\n"
108 "mfspr %0, %1\n"
109 "isync" : "=&r" (hid0) : "i" (SPRN_HID0), "0" (hid0):
110 "memory");
111}
112#endif /* CONFIG_PPC64 */