diff options
Diffstat (limited to 'kernel/arch/powerpc/oprofile/op_model_power4.c')
| -rw-r--r-- | kernel/arch/powerpc/oprofile/op_model_power4.c | 442 |
1 files changed, 442 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/oprofile/op_model_power4.c b/kernel/arch/powerpc/oprofile/op_model_power4.c new file mode 100644 index 000000000..962fe7b3e --- /dev/null +++ b/kernel/arch/powerpc/oprofile/op_model_power4.c @@ -0,0 +1,442 @@ +/* + * Copyright (C) 2004 Anton Blanchard <anton@au.ibm.com>, IBM + * Added mmcra[slot] support: + * Copyright (C) 2006-2007 Will Schmidt <willschm@us.ibm.com>, IBM + * + * 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/oprofile.h> +#include <linux/smp.h> +#include <asm/firmware.h> +#include <asm/ptrace.h> +#include <asm/processor.h> +#include <asm/cputable.h> +#include <asm/rtas.h> +#include <asm/oprofile_impl.h> +#include <asm/reg.h> + +#define dbg(args...) +#define OPROFILE_PM_PMCSEL_MSK 0xffULL +#define OPROFILE_PM_UNIT_SHIFT 60 +#define OPROFILE_PM_UNIT_MSK 0xfULL +#define OPROFILE_MAX_PMC_NUM 3 +#define OPROFILE_PMSEL_FIELD_WIDTH 8 +#define OPROFILE_UNIT_FIELD_WIDTH 4 +#define MMCRA_SIAR_VALID_MASK 0x10000000ULL + +static unsigned long reset_value[OP_MAX_COUNTER]; + +static int oprofile_running; +static int use_slot_nums; + +/* mmcr values are set in power4_reg_setup, used in power4_cpu_setup */ +static u32 mmcr0_val; +static u64 mmcr1_val; +static u64 mmcra_val; +static u32 cntr_marked_events; + +static int power7_marked_instr_event(u64 mmcr1) +{ + u64 psel, unit; + int pmc, cntr_marked_events = 0; + + /* Given the MMCR1 value, look at the field for each counter to + * determine if it is a marked event. Code based on the function + * power7_marked_instr_event() in file arch/powerpc/perf/power7-pmu.c. + */ + for (pmc = 0; pmc < 4; pmc++) { + psel = mmcr1 & (OPROFILE_PM_PMCSEL_MSK + << (OPROFILE_MAX_PMC_NUM - pmc) + * OPROFILE_PMSEL_FIELD_WIDTH); + psel = (psel >> ((OPROFILE_MAX_PMC_NUM - pmc) + * OPROFILE_PMSEL_FIELD_WIDTH)) & ~1ULL; + unit = mmcr1 & (OPROFILE_PM_UNIT_MSK + << (OPROFILE_PM_UNIT_SHIFT + - (pmc * OPROFILE_PMSEL_FIELD_WIDTH ))); + unit = unit >> (OPROFILE_PM_UNIT_SHIFT + - (pmc * OPROFILE_PMSEL_FIELD_WIDTH)); + + switch (psel >> 4) { + case 2: + cntr_marked_events |= (pmc == 1 || pmc == 3) << pmc; + break; + case 3: + if (psel == 0x3c) { + cntr_marked_events |= (pmc == 0) << pmc; + break; + } + + if (psel == 0x3e) { + cntr_marked_events |= (pmc != 1) << pmc; + break; + } + + cntr_marked_events |= 1 << pmc; + break; + case 4: + case 5: + cntr_marked_events |= (unit == 0xd) << pmc; + break; + case 6: + if (psel == 0x64) + cntr_marked_events |= (pmc >= 2) << pmc; + break; + case 8: + cntr_marked_events |= (unit == 0xd) << pmc; + break; + } + } + return cntr_marked_events; +} + +static int power4_reg_setup(struct op_counter_config *ctr, + struct op_system_config *sys, + int num_ctrs) +{ + int i; + + /* + * The performance counter event settings are given in the mmcr0, + * mmcr1 and mmcra values passed from the user in the + * op_system_config structure (sys variable). + */ + mmcr0_val = sys->mmcr0; + mmcr1_val = sys->mmcr1; + mmcra_val = sys->mmcra; + + /* Power 7+ and newer architectures: + * Determine which counter events in the group (the group of events is + * specified by the bit settings in the MMCR1 register) are marked + * events for use in the interrupt handler. Do the calculation once + * before OProfile starts. Information is used in the interrupt + * handler. Starting with Power 7+ we only record the sample for + * marked events if the SIAR valid bit is set. For non marked events + * the sample is always recorded. + */ + if (pvr_version_is(PVR_POWER7p)) + cntr_marked_events = power7_marked_instr_event(mmcr1_val); + else + cntr_marked_events = 0; /* For older processors, set the bit map + * to zero so the sample will always be + * be recorded. + */ + + for (i = 0; i < cur_cpu_spec->num_pmcs; ++i) + reset_value[i] = 0x80000000UL - ctr[i].count; + + /* setup user and kernel profiling */ + if (sys->enable_kernel) + mmcr0_val &= ~MMCR0_KERNEL_DISABLE; + else + mmcr0_val |= MMCR0_KERNEL_DISABLE; + + if (sys->enable_user) + mmcr0_val &= ~MMCR0_PROBLEM_DISABLE; + else + mmcr0_val |= MMCR0_PROBLEM_DISABLE; + + if (pvr_version_is(PVR_POWER4) || pvr_version_is(PVR_POWER4p) || + pvr_version_is(PVR_970) || pvr_version_is(PVR_970FX) || + pvr_version_is(PVR_970MP) || pvr_version_is(PVR_970GX) || + pvr_version_is(PVR_POWER5) || pvr_version_is(PVR_POWER5p)) + use_slot_nums = 1; + + return 0; +} + +extern void ppc_enable_pmcs(void); + +/* + * Older CPUs require the MMCRA sample bit to be always set, but newer + * CPUs only want it set for some groups. Eventually we will remove all + * knowledge of this bit in the kernel, oprofile userspace should be + * setting it when required. + * + * In order to keep current installations working we force the bit for + * those older CPUs. Once everyone has updated their oprofile userspace we + * can remove this hack. + */ +static inline int mmcra_must_set_sample(void) +{ + if (pvr_version_is(PVR_POWER4) || pvr_version_is(PVR_POWER4p) || + pvr_version_is(PVR_970) || pvr_version_is(PVR_970FX) || + pvr_version_is(PVR_970MP) || pvr_version_is(PVR_970GX)) + return 1; + + return 0; +} + +static int power4_cpu_setup(struct op_counter_config *ctr) +{ + unsigned int mmcr0 = mmcr0_val; + unsigned long mmcra = mmcra_val; + + ppc_enable_pmcs(); + + /* set the freeze bit */ + mmcr0 |= MMCR0_FC; + mtspr(SPRN_MMCR0, mmcr0); + + mmcr0 |= MMCR0_FCM1|MMCR0_PMXE|MMCR0_FCECE; + mmcr0 |= MMCR0_PMC1CE|MMCR0_PMCjCE; + mtspr(SPRN_MMCR0, mmcr0); + + mtspr(SPRN_MMCR1, mmcr1_val); + + if (mmcra_must_set_sample()) + mmcra |= MMCRA_SAMPLE_ENABLE; + mtspr(SPRN_MMCRA, mmcra); + + dbg("setup on cpu %d, mmcr0 %lx\n", smp_processor_id(), + mfspr(SPRN_MMCR0)); + dbg("setup on cpu %d, mmcr1 %lx\n", smp_processor_id(), + mfspr(SPRN_MMCR1)); + dbg("setup on cpu %d, mmcra %lx\n", smp_processor_id(), + mfspr(SPRN_MMCRA)); + + return 0; +} + +static int power4_start(struct op_counter_config *ctr) +{ + int i; + unsigned int mmcr0; + + /* set the PMM bit (see comment below) */ + mtmsrd(mfmsr() | MSR_PMM); + + for (i = 0; i < cur_cpu_spec->num_pmcs; ++i) { + if (ctr[i].enabled) { + classic_ctr_write(i, reset_value[i]); + } else { + classic_ctr_write(i, 0); + } + } + + mmcr0 = mfspr(SPRN_MMCR0); + + /* + * We must clear the PMAO bit on some (GQ) chips. Just do it + * all the time + */ + mmcr0 &= ~MMCR0_PMAO; + + /* + * now clear the freeze bit, counting will not start until we + * rfid from this excetion, because only at that point will + * the PMM bit be cleared + */ + mmcr0 &= ~MMCR0_FC; + mtspr(SPRN_MMCR0, mmcr0); + + oprofile_running = 1; + + dbg("start on cpu %d, mmcr0 %x\n", smp_processor_id(), mmcr0); + return 0; +} + +static void power4_stop(void) +{ + unsigned int mmcr0; + + /* freeze counters */ + mmcr0 = mfspr(SPRN_MMCR0); + mmcr0 |= MMCR0_FC; + mtspr(SPRN_MMCR0, mmcr0); + + oprofile_running = 0; + + dbg("stop on cpu %d, mmcr0 %x\n", smp_processor_id(), mmcr0); + + mb(); +} + +/* Fake functions used by canonicalize_pc */ +static void __used hypervisor_bucket(void) +{ +} + +static void __used rtas_bucket(void) +{ +} + +static void __used kernel_unknown_bucket(void) +{ +} + +/* + * On GQ and newer the MMCRA stores the HV and PR bits at the time + * the SIAR was sampled. We use that to work out if the SIAR was sampled in + * the hypervisor, our exception vectors or RTAS. + * If the MMCRA_SAMPLE_ENABLE bit is set, we can use the MMCRA[slot] bits + * to more accurately identify the address of the sampled instruction. The + * mmcra[slot] bits represent the slot number of a sampled instruction + * within an instruction group. The slot will contain a value between 1 + * and 5 if MMCRA_SAMPLE_ENABLE is set, otherwise 0. + */ +static unsigned long get_pc(struct pt_regs *regs) +{ + unsigned long pc = mfspr(SPRN_SIAR); + unsigned long mmcra; + unsigned long slot; + + /* Can't do much about it */ + if (!cur_cpu_spec->oprofile_mmcra_sihv) + return pc; + + mmcra = mfspr(SPRN_MMCRA); + + if (use_slot_nums && (mmcra & MMCRA_SAMPLE_ENABLE)) { + slot = ((mmcra & MMCRA_SLOT) >> MMCRA_SLOT_SHIFT); + if (slot > 1) + pc += 4 * (slot - 1); + } + + /* Were we in the hypervisor? */ + if (firmware_has_feature(FW_FEATURE_LPAR) && + (mmcra & cur_cpu_spec->oprofile_mmcra_sihv)) + /* function descriptor madness */ + return *((unsigned long *)hypervisor_bucket); + + /* We were in userspace, nothing to do */ + if (mmcra & cur_cpu_spec->oprofile_mmcra_sipr) + return pc; + +#ifdef CONFIG_PPC_RTAS + /* Were we in RTAS? */ + if (pc >= rtas.base && pc < (rtas.base + rtas.size)) + /* function descriptor madness */ + return *((unsigned long *)rtas_bucket); +#endif + + /* Were we in our exception vectors or SLB real mode miss handler? */ + if (pc < 0x1000000UL) + return (unsigned long)__va(pc); + + /* Not sure where we were */ + if (!is_kernel_addr(pc)) + /* function descriptor madness */ + return *((unsigned long *)kernel_unknown_bucket); + + return pc; +} + +static int get_kernel(unsigned long pc, unsigned long mmcra) +{ + int is_kernel; + + if (!cur_cpu_spec->oprofile_mmcra_sihv) { + is_kernel = is_kernel_addr(pc); + } else { + is_kernel = ((mmcra & cur_cpu_spec->oprofile_mmcra_sipr) == 0); + } + + return is_kernel; +} + +static bool pmc_overflow(unsigned long val) +{ + if ((int)val < 0) + return true; + + /* + * Events on POWER7 can roll back if a speculative event doesn't + * eventually complete. Unfortunately in some rare cases they will + * raise a performance monitor exception. We need to catch this to + * ensure we reset the PMC. In all cases the PMC will be 256 or less + * cycles from overflow. + * + * We only do this if the first pass fails to find any overflowing + * PMCs because a user might set a period of less than 256 and we + * don't want to mistakenly reset them. + */ + if (pvr_version_is(PVR_POWER7) && ((0x80000000 - val) <= 256)) + return true; + + return false; +} + +static void power4_handle_interrupt(struct pt_regs *regs, + struct op_counter_config *ctr) +{ + unsigned long pc; + int is_kernel; + int val; + int i; + unsigned int mmcr0; + unsigned long mmcra; + bool siar_valid = false; + + mmcra = mfspr(SPRN_MMCRA); + + pc = get_pc(regs); + is_kernel = get_kernel(pc, mmcra); + + /* set the PMM bit (see comment below) */ + mtmsrd(mfmsr() | MSR_PMM); + + /* Check that the SIAR valid bit in MMCRA is set to 1. */ + if ((mmcra & MMCRA_SIAR_VALID_MASK) == MMCRA_SIAR_VALID_MASK) + siar_valid = true; + + for (i = 0; i < cur_cpu_spec->num_pmcs; ++i) { + val = classic_ctr_read(i); + if (pmc_overflow(val)) { + if (oprofile_running && ctr[i].enabled) { + /* Power 7+ and newer architectures: + * If the event is a marked event, then only + * save the sample if the SIAR valid bit is + * set. If the event is not marked, then + * always save the sample. + * Note, the Sample enable bit in the MMCRA + * register must be set to 1 if the group + * contains a marked event. + */ + if ((siar_valid && + (cntr_marked_events & (1 << i))) + || !(cntr_marked_events & (1 << i))) + oprofile_add_ext_sample(pc, regs, i, + is_kernel); + + classic_ctr_write(i, reset_value[i]); + } else { + classic_ctr_write(i, 0); + } + } + } + + mmcr0 = mfspr(SPRN_MMCR0); + + /* reset the perfmon trigger */ + mmcr0 |= MMCR0_PMXE; + + /* + * We must clear the PMAO bit on some (GQ) chips. Just do it + * all the time + */ + mmcr0 &= ~MMCR0_PMAO; + + /* Clear the appropriate bits in the MMCRA */ + mmcra &= ~cur_cpu_spec->oprofile_mmcra_clear; + mtspr(SPRN_MMCRA, mmcra); + + /* + * now clear the freeze bit, counting will not start until we + * rfid from this exception, because only at that point will + * the PMM bit be cleared + */ + mmcr0 &= ~MMCR0_FC; + mtspr(SPRN_MMCR0, mmcr0); +} + +struct op_powerpc_model op_model_power4 = { + .reg_setup = power4_reg_setup, + .cpu_setup = power4_cpu_setup, + .start = power4_start, + .stop = power4_stop, + .handle_interrupt = power4_handle_interrupt, +}; |