/* * Copyright (C) 2004 Anton Blanchard , IBM * Added mmcra[slot] support: * Copyright (C) 2006-2007 Will Schmidt , 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 #include #include #include #include #include #include #include #include #include #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, };