diff options
Diffstat (limited to 'arch/powerpc/kernel/pmc.c')
-rw-r--r-- | arch/powerpc/kernel/pmc.c | 112 |
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 0000000..2d333cc --- /dev/null +++ b/arch/powerpc/kernel/pmc.c @@ -0,0 +1,112 @@ +/* + * arch/powerpc/kernel/pmc.c + * + * Copyright (C) 2004 David Gibson, IBM Corporation. + * Includes code formerly from arch/ppc/kernel/perfmon.c: + * Author: Andy Fleming + * Copyright (c) 2004 Freescale Semiconductor, Inc + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/config.h> +#include <linux/errno.h> +#include <linux/spinlock.h> +#include <linux/module.h> + +#include <asm/processor.h> +#include <asm/pmc.h> + +#if defined(CONFIG_FSL_BOOKE) && !defined(CONFIG_E200) +static void dummy_perf(struct pt_regs *regs) +{ + unsigned int pmgc0 = mfpmr(PMRN_PMGC0); + + pmgc0 &= ~PMGC0_PMIE; + mtpmr(PMRN_PMGC0, pmgc0); +} +#elif defined(CONFIG_PPC64) || defined(CONFIG_6xx) + +#ifndef MMCR0_PMAO +#define MMCR0_PMAO 0 +#endif + +/* Ensure exceptions are disabled */ +static void dummy_perf(struct pt_regs *regs) +{ + unsigned int mmcr0 = mfspr(SPRN_MMCR0); + + mmcr0 &= ~(MMCR0_PMXE|MMCR0_PMAO); + mtspr(SPRN_MMCR0, mmcr0); +} +#else +static void dummy_perf(struct pt_regs *regs) +{ +} +#endif + +static DEFINE_SPINLOCK(pmc_owner_lock); +static void *pmc_owner_caller; /* mostly for debugging */ +perf_irq_t perf_irq = dummy_perf; + +int reserve_pmc_hardware(perf_irq_t new_perf_irq) +{ + int err = 0; + + spin_lock(&pmc_owner_lock); + + if (pmc_owner_caller) { + printk(KERN_WARNING "reserve_pmc_hardware: " + "PMC hardware busy (reserved by caller %p)\n", + pmc_owner_caller); + err = -EBUSY; + goto out; + } + + pmc_owner_caller = __builtin_return_address(0); + perf_irq = new_perf_irq ? : dummy_perf; + + out: + spin_unlock(&pmc_owner_lock); + return err; +} +EXPORT_SYMBOL_GPL(reserve_pmc_hardware); + +void release_pmc_hardware(void) +{ + spin_lock(&pmc_owner_lock); + + WARN_ON(! pmc_owner_caller); + + pmc_owner_caller = NULL; + perf_irq = dummy_perf; + + spin_unlock(&pmc_owner_lock); +} +EXPORT_SYMBOL_GPL(release_pmc_hardware); + +#ifdef CONFIG_PPC64 +void power4_enable_pmcs(void) +{ + unsigned long hid0; + + hid0 = mfspr(SPRN_HID0); + hid0 |= 1UL << (63 - 20); + + /* POWER4 requires the following sequence */ + asm volatile( + "sync\n" + "mtspr %1, %0\n" + "mfspr %0, %1\n" + "mfspr %0, %1\n" + "mfspr %0, %1\n" + "mfspr %0, %1\n" + "mfspr %0, %1\n" + "mfspr %0, %1\n" + "isync" : "=&r" (hid0) : "i" (SPRN_HID0), "0" (hid0): + "memory"); +} +#endif /* CONFIG_PPC64 */ |