blob: 918f6b252e454cc9c8a3374abfe0bc6b57e60569 [file] [log] [blame]
/* kernel/perfmon.c
* PPC 32 Performance Monitor Infrastructure
*
* 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/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/interrupt.h>
#include <linux/config.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/prctl.h>
#include <asm/pgtable.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/reg.h>
#include <asm/xmon.h>
/* A lock to regulate grabbing the interrupt */
DEFINE_SPINLOCK(perfmon_lock);
#ifdef CONFIG_FSL_BOOKE
static void dummy_perf(struct pt_regs *regs)
{
unsigned int pmgc0 = mfpmr(PMRN_PMGC0);
pmgc0 &= ~PMGC0_PMIE;
mtpmr(PMRN_PMGC0, pmgc0);
}
#else
/* Ensure exceptions are disabled */
static void dummy_perf(struct pt_regs *regs)
{
unsigned int mmcr0 = mfspr(SPRN_MMCR0);
mmcr0 &= ~MMCR0_PMXE;
mtspr(SPRN_MMCR0, mmcr0);
}
#endif
void (*perf_irq)(struct pt_regs *) = dummy_perf;
/* Grab the interrupt, if it's free.
* Returns 0 on success, -1 if the interrupt is taken already */
int request_perfmon_irq(void (*handler)(struct pt_regs *))
{
int err = 0;
spin_lock(&perfmon_lock);
if (perf_irq == dummy_perf)
perf_irq = handler;
else {
pr_info("perfmon irq already handled by %p\n", perf_irq);
err = -1;
}
spin_unlock(&perfmon_lock);
return err;
}
void free_perfmon_irq(void)
{
spin_lock(&perfmon_lock);
perf_irq = dummy_perf;
spin_unlock(&perfmon_lock);
}
EXPORT_SYMBOL(perf_irq);
EXPORT_SYMBOL(request_perfmon_irq);
EXPORT_SYMBOL(free_perfmon_irq);