summaryrefslogtreecommitdiff
path: root/arch/blackfin/kernel/perf_event.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/blackfin/kernel/perf_event.c')
-rw-r--r--arch/blackfin/kernel/perf_event.c498
1 files changed, 498 insertions, 0 deletions
diff --git a/arch/blackfin/kernel/perf_event.c b/arch/blackfin/kernel/perf_event.c
new file mode 100644
index 0000000..04300f2
--- /dev/null
+++ b/arch/blackfin/kernel/perf_event.c
@@ -0,0 +1,498 @@
+/*
+ * Blackfin performance counters
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Ripped from SuperH version:
+ *
+ * Copyright (C) 2009 Paul Mundt
+ *
+ * Heavily based on the x86 and PowerPC implementations.
+ *
+ * x86:
+ * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
+ * Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar
+ * Copyright (C) 2009 Jaswinder Singh Rajput
+ * Copyright (C) 2009 Advanced Micro Devices, Inc., Robert Richter
+ * Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2009 Intel Corporation, <markus.t.metzger@intel.com>
+ *
+ * ppc:
+ * Copyright 2008-2009 Paul Mackerras, IBM Corporation.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/perf_event.h>
+#include <asm/bfin_pfmon.h>
+
+/*
+ * We have two counters, and each counter can support an event type.
+ * The 'o' is PFCNTx=1 and 's' is PFCNTx=0
+ *
+ * 0x04 o pc invariant branches
+ * 0x06 o mispredicted branches
+ * 0x09 o predicted branches taken
+ * 0x0B o EXCPT insn
+ * 0x0C o CSYNC/SSYNC insn
+ * 0x0D o Insns committed
+ * 0x0E o Interrupts taken
+ * 0x0F o Misaligned address exceptions
+ * 0x80 o Code memory fetches stalled due to DMA
+ * 0x83 o 64bit insn fetches delivered
+ * 0x9A o data cache fills (bank a)
+ * 0x9B o data cache fills (bank b)
+ * 0x9C o data cache lines evicted (bank a)
+ * 0x9D o data cache lines evicted (bank b)
+ * 0x9E o data cache high priority fills
+ * 0x9F o data cache low priority fills
+ * 0x00 s loop 0 iterations
+ * 0x01 s loop 1 iterations
+ * 0x0A s CSYNC/SSYNC stalls
+ * 0x10 s DAG read/after write hazards
+ * 0x13 s RAW data hazards
+ * 0x81 s code TAG stalls
+ * 0x82 s code fill stalls
+ * 0x90 s processor to memory stalls
+ * 0x91 s data memory stalls not hidden by 0x90
+ * 0x92 s data store buffer full stalls
+ * 0x93 s data memory write buffer full stalls due to high->low priority
+ * 0x95 s data memory fill buffer stalls
+ * 0x96 s data TAG collision stalls
+ * 0x97 s data collision stalls
+ * 0x98 s data stalls
+ * 0x99 s data stalls sent to processor
+ */
+
+static const int event_map[] = {
+ /* use CYCLES cpu register */
+ [PERF_COUNT_HW_CPU_CYCLES] = -1,
+ [PERF_COUNT_HW_INSTRUCTIONS] = 0x0D,
+ [PERF_COUNT_HW_CACHE_REFERENCES] = -1,
+ [PERF_COUNT_HW_CACHE_MISSES] = 0x83,
+ [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = 0x09,
+ [PERF_COUNT_HW_BRANCH_MISSES] = 0x06,
+ [PERF_COUNT_HW_BUS_CYCLES] = -1,
+};
+
+#define C(x) PERF_COUNT_HW_CACHE_##x
+
+static const int cache_events[PERF_COUNT_HW_CACHE_MAX]
+ [PERF_COUNT_HW_CACHE_OP_MAX]
+ [PERF_COUNT_HW_CACHE_RESULT_MAX] =
+{
+ [C(L1D)] = { /* Data bank A */
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = 0,
+ [C(RESULT_MISS) ] = 0x9A,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = 0,
+ [C(RESULT_MISS) ] = 0,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = 0,
+ [C(RESULT_MISS) ] = 0,
+ },
+ },
+
+ [C(L1I)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = 0,
+ [C(RESULT_MISS) ] = 0x83,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = -1,
+ [C(RESULT_MISS) ] = -1,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = 0,
+ [C(RESULT_MISS) ] = 0,
+ },
+ },
+
+ [C(LL)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = -1,
+ [C(RESULT_MISS) ] = -1,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = -1,
+ [C(RESULT_MISS) ] = -1,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = -1,
+ [C(RESULT_MISS) ] = -1,
+ },
+ },
+
+ [C(DTLB)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = -1,
+ [C(RESULT_MISS) ] = -1,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = -1,
+ [C(RESULT_MISS) ] = -1,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = -1,
+ [C(RESULT_MISS) ] = -1,
+ },
+ },
+
+ [C(ITLB)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = -1,
+ [C(RESULT_MISS) ] = -1,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = -1,
+ [C(RESULT_MISS) ] = -1,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = -1,
+ [C(RESULT_MISS) ] = -1,
+ },
+ },
+
+ [C(BPU)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = -1,
+ [C(RESULT_MISS) ] = -1,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = -1,
+ [C(RESULT_MISS) ] = -1,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = -1,
+ [C(RESULT_MISS) ] = -1,
+ },
+ },
+};
+
+const char *perf_pmu_name(void)
+{
+ return "bfin";
+}
+EXPORT_SYMBOL(perf_pmu_name);
+
+int perf_num_counters(void)
+{
+ return ARRAY_SIZE(event_map);
+}
+EXPORT_SYMBOL(perf_num_counters);
+
+static u64 bfin_pfmon_read(int idx)
+{
+ return bfin_read32(PFCNTR0 + (idx * 4));
+}
+
+static void bfin_pfmon_disable(struct hw_perf_event *hwc, int idx)
+{
+ bfin_write_PFCTL(bfin_read_PFCTL() & ~PFCEN(idx, PFCEN_MASK));
+}
+
+static void bfin_pfmon_enable(struct hw_perf_event *hwc, int idx)
+{
+ u32 val, mask;
+
+ val = PFPWR;
+ if (idx) {
+ mask = ~(PFCNT1 | PFMON1 | PFCEN1 | PEMUSW1);
+ /* The packed config is for event0, so shift it to event1 slots */
+ val |= (hwc->config << (PFMON1_P - PFMON0_P));
+ val |= (hwc->config & PFCNT0) << (PFCNT1_P - PFCNT0_P);
+ bfin_write_PFCNTR1(0);
+ } else {
+ mask = ~(PFCNT0 | PFMON0 | PFCEN0 | PEMUSW0);
+ val |= hwc->config;
+ bfin_write_PFCNTR0(0);
+ }
+
+ bfin_write_PFCTL((bfin_read_PFCTL() & mask) | val);
+}
+
+static void bfin_pfmon_disable_all(void)
+{
+ bfin_write_PFCTL(bfin_read_PFCTL() & ~PFPWR);
+}
+
+static void bfin_pfmon_enable_all(void)
+{
+ bfin_write_PFCTL(bfin_read_PFCTL() | PFPWR);
+}
+
+struct cpu_hw_events {
+ struct perf_event *events[MAX_HWEVENTS];
+ unsigned long used_mask[BITS_TO_LONGS(MAX_HWEVENTS)];
+};
+DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events);
+
+static int hw_perf_cache_event(int config, int *evp)
+{
+ unsigned long type, op, result;
+ int ev;
+
+ /* unpack config */
+ type = config & 0xff;
+ op = (config >> 8) & 0xff;
+ result = (config >> 16) & 0xff;
+
+ if (type >= PERF_COUNT_HW_CACHE_MAX ||
+ op >= PERF_COUNT_HW_CACHE_OP_MAX ||
+ result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
+ return -EINVAL;
+
+ ev = cache_events[type][op][result];
+ if (ev == 0)
+ return -EOPNOTSUPP;
+ if (ev == -1)
+ return -EINVAL;
+ *evp = ev;
+ return 0;
+}
+
+static void bfin_perf_event_update(struct perf_event *event,
+ struct hw_perf_event *hwc, int idx)
+{
+ u64 prev_raw_count, new_raw_count;
+ s64 delta;
+ int shift = 0;
+
+ /*
+ * Depending on the counter configuration, they may or may not
+ * be chained, in which case the previous counter value can be
+ * updated underneath us if the lower-half overflows.
+ *
+ * Our tactic to handle this is to first atomically read and
+ * exchange a new raw count - then add that new-prev delta
+ * count to the generic counter atomically.
+ *
+ * As there is no interrupt associated with the overflow events,
+ * this is the simplest approach for maintaining consistency.
+ */
+again:
+ prev_raw_count = local64_read(&hwc->prev_count);
+ new_raw_count = bfin_pfmon_read(idx);
+
+ if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
+ new_raw_count) != prev_raw_count)
+ goto again;
+
+ /*
+ * Now we have the new raw value and have updated the prev
+ * timestamp already. We can now calculate the elapsed delta
+ * (counter-)time and add that to the generic counter.
+ *
+ * Careful, not all hw sign-extends above the physical width
+ * of the count.
+ */
+ delta = (new_raw_count << shift) - (prev_raw_count << shift);
+ delta >>= shift;
+
+ local64_add(delta, &event->count);
+}
+
+static void bfin_pmu_stop(struct perf_event *event, int flags)
+{
+ struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+ struct hw_perf_event *hwc = &event->hw;
+ int idx = hwc->idx;
+
+ if (!(event->hw.state & PERF_HES_STOPPED)) {
+ bfin_pfmon_disable(hwc, idx);
+ cpuc->events[idx] = NULL;
+ event->hw.state |= PERF_HES_STOPPED;
+ }
+
+ if ((flags & PERF_EF_UPDATE) && !(event->hw.state & PERF_HES_UPTODATE)) {
+ bfin_perf_event_update(event, &event->hw, idx);
+ event->hw.state |= PERF_HES_UPTODATE;
+ }
+}
+
+static void bfin_pmu_start(struct perf_event *event, int flags)
+{
+ struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+ struct hw_perf_event *hwc = &event->hw;
+ int idx = hwc->idx;
+
+ if (WARN_ON_ONCE(idx == -1))
+ return;
+
+ if (flags & PERF_EF_RELOAD)
+ WARN_ON_ONCE(!(event->hw.state & PERF_HES_UPTODATE));
+
+ cpuc->events[idx] = event;
+ event->hw.state = 0;
+ bfin_pfmon_enable(hwc, idx);
+}
+
+static void bfin_pmu_del(struct perf_event *event, int flags)
+{
+ struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+
+ bfin_pmu_stop(event, PERF_EF_UPDATE);
+ __clear_bit(event->hw.idx, cpuc->used_mask);
+
+ perf_event_update_userpage(event);
+}
+
+static int bfin_pmu_add(struct perf_event *event, int flags)
+{
+ struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+ struct hw_perf_event *hwc = &event->hw;
+ int idx = hwc->idx;
+ int ret = -EAGAIN;
+
+ perf_pmu_disable(event->pmu);
+
+ if (__test_and_set_bit(idx, cpuc->used_mask)) {
+ idx = find_first_zero_bit(cpuc->used_mask, MAX_HWEVENTS);
+ if (idx == MAX_HWEVENTS)
+ goto out;
+
+ __set_bit(idx, cpuc->used_mask);
+ hwc->idx = idx;
+ }
+
+ bfin_pfmon_disable(hwc, idx);
+
+ event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
+ if (flags & PERF_EF_START)
+ bfin_pmu_start(event, PERF_EF_RELOAD);
+
+ perf_event_update_userpage(event);
+ ret = 0;
+out:
+ perf_pmu_enable(event->pmu);
+ return ret;
+}
+
+static void bfin_pmu_read(struct perf_event *event)
+{
+ bfin_perf_event_update(event, &event->hw, event->hw.idx);
+}
+
+static int bfin_pmu_event_init(struct perf_event *event)
+{
+ struct perf_event_attr *attr = &event->attr;
+ struct hw_perf_event *hwc = &event->hw;
+ int config = -1;
+ int ret;
+
+ if (attr->exclude_hv || attr->exclude_idle)
+ return -EPERM;
+
+ /*
+ * All of the on-chip counters are "limited", in that they have
+ * no interrupts, and are therefore unable to do sampling without
+ * further work and timer assistance.
+ */
+ if (hwc->sample_period)
+ return -EINVAL;
+
+ ret = 0;
+ switch (attr->type) {
+ case PERF_TYPE_RAW:
+ config = PFMON(0, attr->config & PFMON_MASK) |
+ PFCNT(0, !(attr->config & 0x100));
+ break;
+ case PERF_TYPE_HW_CACHE:
+ ret = hw_perf_cache_event(attr->config, &config);
+ break;
+ case PERF_TYPE_HARDWARE:
+ if (attr->config >= ARRAY_SIZE(event_map))
+ return -EINVAL;
+
+ config = event_map[attr->config];
+ break;
+ }
+
+ if (config == -1)
+ return -EINVAL;
+
+ if (!attr->exclude_kernel)
+ config |= PFCEN(0, PFCEN_ENABLE_SUPV);
+ if (!attr->exclude_user)
+ config |= PFCEN(0, PFCEN_ENABLE_USER);
+
+ hwc->config |= config;
+
+ return ret;
+}
+
+static void bfin_pmu_enable(struct pmu *pmu)
+{
+ struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+ struct perf_event *event;
+ struct hw_perf_event *hwc;
+ int i;
+
+ for (i = 0; i < MAX_HWEVENTS; ++i) {
+ event = cpuc->events[i];
+ if (!event)
+ continue;
+ hwc = &event->hw;
+ bfin_pfmon_enable(hwc, hwc->idx);
+ }
+
+ bfin_pfmon_enable_all();
+}
+
+static void bfin_pmu_disable(struct pmu *pmu)
+{
+ bfin_pfmon_disable_all();
+}
+
+static struct pmu pmu = {
+ .pmu_enable = bfin_pmu_enable,
+ .pmu_disable = bfin_pmu_disable,
+ .event_init = bfin_pmu_event_init,
+ .add = bfin_pmu_add,
+ .del = bfin_pmu_del,
+ .start = bfin_pmu_start,
+ .stop = bfin_pmu_stop,
+ .read = bfin_pmu_read,
+};
+
+static void bfin_pmu_setup(int cpu)
+{
+ struct cpu_hw_events *cpuhw = &per_cpu(cpu_hw_events, cpu);
+
+ memset(cpuhw, 0, sizeof(struct cpu_hw_events));
+}
+
+static int __cpuinit
+bfin_pmu_notifier(struct notifier_block *self, unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (long)hcpu;
+
+ switch (action & ~CPU_TASKS_FROZEN) {
+ case CPU_UP_PREPARE:
+ bfin_write_PFCTL(0);
+ bfin_pmu_setup(cpu);
+ break;
+
+ default:
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static int __init bfin_pmu_init(void)
+{
+ int ret;
+
+ ret = perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW);
+ if (!ret)
+ perf_cpu_notifier(bfin_pmu_notifier);
+
+ return ret;
+}
+early_initcall(bfin_pmu_init);
generated by cgit v0.10.2 at 2024-10-30 23:53:12 (GMT)