[PATCH] powerpc: Merge ppc64 pmc.[ch] with ppc32 perfmon.[ch]
[linux-2.6] / arch / powerpc / kernel / pmc.c
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)
24 static 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 */
38 static 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
46 static void dummy_perf(struct pt_regs *regs)
47 {
48 }
49 #endif
50
51 static DEFINE_SPINLOCK(pmc_owner_lock);
52 static void *pmc_owner_caller; /* mostly for debugging */
53 perf_irq_t perf_irq = dummy_perf;
54
55 int 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 }
76 EXPORT_SYMBOL_GPL(reserve_pmc_hardware);
77
78 void 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 }
89 EXPORT_SYMBOL_GPL(release_pmc_hardware);
90
91 #ifdef CONFIG_PPC64
92 void 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 */