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-rw-r--r--kernel/arch/powerpc/oprofile/op_model_power4.c442
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
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index 000000000..962fe7b3e
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+++ b/kernel/arch/powerpc/oprofile/op_model_power4.c
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+/*
+ * 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,
+};