linux/arch/powerpc/kernel/pmc.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

99 lines
2.1 KiB
C

// 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 */