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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/powerpc/kernel/pmc.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | arch/powerpc/kernel/pmc.c | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/pmc.c b/arch/powerpc/kernel/pmc.c new file mode 100644 index 000000000..15414c8a2 --- /dev/null +++ b/arch/powerpc/kernel/pmc.c @@ -0,0 +1,98 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * 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 + */ + +#include <linux/errno.h> +#include <linux/bug.h> +#include <linux/spinlock.h> +#include <linux/export.h> + +#include <asm/processor.h> +#include <asm/cputable.h> +#include <asm/pmc.h> + +#ifndef MMCR0_PMAO +#define MMCR0_PMAO 0 +#endif + +static void dummy_perf(struct pt_regs *regs) +{ +#if defined(CONFIG_FSL_EMB_PERFMON) + mtpmr(PMRN_PMGC0, mfpmr(PMRN_PMGC0) & ~PMGC0_PMIE); +#elif defined(CONFIG_PPC64) || defined(CONFIG_PPC_BOOK3S_32) + if (cur_cpu_spec->pmc_type == PPC_PMC_IBM) + mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) & ~(MMCR0_PMXE|MMCR0_PMAO)); +#else + mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) & ~MMCR0_PMXE); +#endif +} + + +static DEFINE_RAW_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; + + raw_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 ? new_perf_irq : dummy_perf; + + out: + raw_spin_unlock(&pmc_owner_lock); + return err; +} +EXPORT_SYMBOL_GPL(reserve_pmc_hardware); + +void release_pmc_hardware(void) +{ + raw_spin_lock(&pmc_owner_lock); + + WARN_ON(! pmc_owner_caller); + + pmc_owner_caller = NULL; + perf_irq = dummy_perf; + + raw_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 */ |