diff options
Diffstat (limited to 'arch/ppc/kernel/perfmon.c')
-rw-r--r-- | arch/ppc/kernel/perfmon.c | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/arch/ppc/kernel/perfmon.c b/arch/ppc/kernel/perfmon.c new file mode 100644 index 0000000..918f6b2 --- /dev/null +++ b/arch/ppc/kernel/perfmon.c @@ -0,0 +1,93 @@ +/* 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); |