Commit 0dd450fe authored by Mischa Jonker's avatar Mischa Jonker Committed by Vineet Gupta

ARC: Add perf support for ARC700 cores

This adds basic perf support for ARC700 cores. Most PERF_COUNT_HW* events
are supported now.
Signed-off-by: default avatarMischa Jonker <mjonker@synopsys.com>
Acked-by: default avatarPeter Zijlstra <peterz@infradead.org>
Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
parent 9c8e612d
......@@ -67,5 +67,9 @@ phy0: ethernet-phy@0 {
reg = <1>;
};
};
arcpmu0: pmu {
compatible = "snps,arc700-pmu";
};
};
};
/*
* Copyright (C) 2011-2012 Synopsys, Inc. (www.synopsys.com)
* Linux performance counter support for ARC
*
* Copyright (C) 2011-2013 Synopsys, Inc. (www.synopsys.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
......@@ -10,4 +12,204 @@
#ifndef __ASM_PERF_EVENT_H
#define __ASM_PERF_EVENT_H
/* real maximum varies per CPU, this is the maximum supported by the driver */
#define ARC_PMU_MAX_HWEVENTS 64
#define ARC_REG_CC_BUILD 0xF6
#define ARC_REG_CC_INDEX 0x240
#define ARC_REG_CC_NAME0 0x241
#define ARC_REG_CC_NAME1 0x242
#define ARC_REG_PCT_BUILD 0xF5
#define ARC_REG_PCT_COUNTL 0x250
#define ARC_REG_PCT_COUNTH 0x251
#define ARC_REG_PCT_SNAPL 0x252
#define ARC_REG_PCT_SNAPH 0x253
#define ARC_REG_PCT_CONFIG 0x254
#define ARC_REG_PCT_CONTROL 0x255
#define ARC_REG_PCT_INDEX 0x256
#define ARC_REG_PCT_CONTROL_CC (1 << 16) /* clear counts */
#define ARC_REG_PCT_CONTROL_SN (1 << 17) /* snapshot */
struct arc_reg_pct_build {
#ifdef CONFIG_CPU_BIG_ENDIAN
unsigned int m:8, c:8, r:6, s:2, v:8;
#else
unsigned int v:8, s:2, r:6, c:8, m:8;
#endif
};
struct arc_reg_cc_build {
#ifdef CONFIG_CPU_BIG_ENDIAN
unsigned int c:16, r:8, v:8;
#else
unsigned int v:8, r:8, c:16;
#endif
};
#define PERF_COUNT_ARC_DCLM (PERF_COUNT_HW_MAX + 0)
#define PERF_COUNT_ARC_DCSM (PERF_COUNT_HW_MAX + 1)
#define PERF_COUNT_ARC_ICM (PERF_COUNT_HW_MAX + 2)
#define PERF_COUNT_ARC_BPOK (PERF_COUNT_HW_MAX + 3)
#define PERF_COUNT_ARC_EDTLB (PERF_COUNT_HW_MAX + 4)
#define PERF_COUNT_ARC_EITLB (PERF_COUNT_HW_MAX + 5)
#define PERF_COUNT_ARC_HW_MAX (PERF_COUNT_HW_MAX + 6)
/*
* The "generalized" performance events seem to really be a copy
* of the available events on x86 processors; the mapping to ARC
* events is not always possible 1-to-1. Fortunately, there doesn't
* seem to be an exact definition for these events, so we can cheat
* a bit where necessary.
*
* In particular, the following PERF events may behave a bit differently
* compared to other architectures:
*
* PERF_COUNT_HW_CPU_CYCLES
* Cycles not in halted state
*
* PERF_COUNT_HW_REF_CPU_CYCLES
* Reference cycles not in halted state, same as PERF_COUNT_HW_CPU_CYCLES
* for now as we don't do Dynamic Voltage/Frequency Scaling (yet)
*
* PERF_COUNT_HW_BUS_CYCLES
* Unclear what this means, Intel uses 0x013c, which according to
* their datasheet means "unhalted reference cycles". It sounds similar
* to PERF_COUNT_HW_REF_CPU_CYCLES, and we use the same counter for it.
*
* PERF_COUNT_HW_STALLED_CYCLES_BACKEND
* PERF_COUNT_HW_STALLED_CYCLES_FRONTEND
* The ARC 700 can either measure stalls per pipeline stage, or all stalls
* combined; for now we assign all stalls to STALLED_CYCLES_BACKEND
* and all pipeline flushes (e.g. caused by mispredicts, etc.) to
* STALLED_CYCLES_FRONTEND.
*
* We could start multiple performance counters and combine everything
* afterwards, but that makes it complicated.
*
* Note that I$ cache misses aren't counted by either of the two!
*/
static const char * const arc_pmu_ev_hw_map[] = {
[PERF_COUNT_HW_CPU_CYCLES] = "crun",
[PERF_COUNT_HW_REF_CPU_CYCLES] = "crun",
[PERF_COUNT_HW_BUS_CYCLES] = "crun",
[PERF_COUNT_HW_INSTRUCTIONS] = "iall",
[PERF_COUNT_HW_BRANCH_MISSES] = "bpfail",
[PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = "ijmp",
[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = "bflush",
[PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = "bstall",
[PERF_COUNT_ARC_DCLM] = "dclm",
[PERF_COUNT_ARC_DCSM] = "dcsm",
[PERF_COUNT_ARC_ICM] = "icm",
[PERF_COUNT_ARC_BPOK] = "bpok",
[PERF_COUNT_ARC_EDTLB] = "edtlb",
[PERF_COUNT_ARC_EITLB] = "eitlb",
};
#define C(_x) PERF_COUNT_HW_CACHE_##_x
#define CACHE_OP_UNSUPPORTED 0xffff
static const unsigned arc_pmu_cache_map[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
[C(L1D)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = PERF_COUNT_ARC_DCLM,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = PERF_COUNT_ARC_DCSM,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
[C(L1I)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = PERF_COUNT_ARC_ICM,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
[C(LL)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
[C(DTLB)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = PERF_COUNT_ARC_EDTLB,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
[C(ITLB)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = PERF_COUNT_ARC_EITLB,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
[C(BPU)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = PERF_COUNT_HW_BRANCH_INSTRUCTIONS,
[C(RESULT_MISS)] = PERF_COUNT_HW_BRANCH_MISSES,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
[C(NODE)] = {
[C(OP_READ)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_WRITE)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
[C(OP_PREFETCH)] = {
[C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
[C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
},
},
};
#endif /* __ASM_PERF_EVENT_H */
......@@ -19,6 +19,7 @@ obj-$(CONFIG_KPROBES) += kprobes.o
obj-$(CONFIG_ARC_MISALIGN_ACCESS) += unaligned.o
obj-$(CONFIG_KGDB) += kgdb.o
obj-$(CONFIG_ARC_METAWARE_HLINK) += arc_hostlink.o
obj-$(CONFIG_PERF_EVENTS) += perf_event.o
obj-$(CONFIG_ARC_FPU_SAVE_RESTORE) += fpu.o
CFLAGS_fpu.o += -mdpfp
......
/*
* Linux performance counter support for ARC700 series
*
* Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com)
*
* This code is inspired by the perf support of various other architectures.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/perf_event.h>
#include <linux/platform_device.h>
#include <asm/arcregs.h>
struct arc_pmu {
struct pmu pmu;
int counter_size; /* in bits */
int n_counters;
unsigned long used_mask[BITS_TO_LONGS(ARC_PMU_MAX_HWEVENTS)];
int ev_hw_idx[PERF_COUNT_ARC_HW_MAX];
};
/* read counter #idx; note that counter# != event# on ARC! */
static uint64_t arc_pmu_read_counter(int idx)
{
uint32_t tmp;
uint64_t result;
/*
* ARC supports making 'snapshots' of the counters, so we don't
* need to care about counters wrapping to 0 underneath our feet
*/
write_aux_reg(ARC_REG_PCT_INDEX, idx);
tmp = read_aux_reg(ARC_REG_PCT_CONTROL);
write_aux_reg(ARC_REG_PCT_CONTROL, tmp | ARC_REG_PCT_CONTROL_SN);
result = (uint64_t) (read_aux_reg(ARC_REG_PCT_SNAPH)) << 32;
result |= read_aux_reg(ARC_REG_PCT_SNAPL);
return result;
}
static void arc_perf_event_update(struct perf_event *event,
struct hw_perf_event *hwc, int idx)
{
struct arc_pmu *arc_pmu = container_of(event->pmu, struct arc_pmu, pmu);
uint64_t prev_raw_count, new_raw_count;
int64_t delta;
do {
prev_raw_count = local64_read(&hwc->prev_count);
new_raw_count = arc_pmu_read_counter(idx);
} while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
new_raw_count) != prev_raw_count);
delta = (new_raw_count - prev_raw_count) &
((1ULL << arc_pmu->counter_size) - 1ULL);
local64_add(delta, &event->count);
local64_sub(delta, &hwc->period_left);
}
static void arc_pmu_read(struct perf_event *event)
{
arc_perf_event_update(event, &event->hw, event->hw.idx);
}
static int arc_pmu_cache_event(u64 config)
{
unsigned int cache_type, cache_op, cache_result;
int ret;
cache_type = (config >> 0) & 0xff;
cache_op = (config >> 8) & 0xff;
cache_result = (config >> 16) & 0xff;
if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
return -EINVAL;
if (cache_type >= PERF_COUNT_HW_CACHE_OP_MAX)
return -EINVAL;
if (cache_type >= PERF_COUNT_HW_CACHE_RESULT_MAX)
return -EINVAL;
ret = arc_pmu_cache_map[cache_type][cache_op][cache_result];
if (ret == CACHE_OP_UNSUPPORTED)
return -ENOENT;
return ret;
}
/* initializes hw_perf_event structure if event is supported */
static int arc_pmu_event_init(struct perf_event *event)
{
struct arc_pmu *arc_pmu = container_of(event->pmu, struct arc_pmu, pmu);
struct hw_perf_event *hwc = &event->hw;
int ret;
switch (event->attr.type) {
case PERF_TYPE_HARDWARE:
if (event->attr.config >= PERF_COUNT_HW_MAX)
return -ENOENT;
if (arc_pmu->ev_hw_idx[event->attr.config] < 0)
return -ENOENT;
hwc->config = arc_pmu->ev_hw_idx[event->attr.config];
pr_debug("initializing event %d with cfg %d\n",
(int) event->attr.config, (int) hwc->config);
return 0;
case PERF_TYPE_HW_CACHE:
ret = arc_pmu_cache_event(event->attr.config);
if (ret < 0)
return ret;
hwc->config = arc_pmu->ev_hw_idx[ret];
return 0;
default:
return -ENOENT;
}
}
/* starts all counters */
static void arc_pmu_enable(struct pmu *pmu)
{
uint32_t tmp;
tmp = read_aux_reg(ARC_REG_PCT_CONTROL);
write_aux_reg(ARC_REG_PCT_CONTROL, (tmp & 0xffff0000) | 0x1);
}
/* stops all counters */
static void arc_pmu_disable(struct pmu *pmu)
{
uint32_t tmp;
tmp = read_aux_reg(ARC_REG_PCT_CONTROL);
write_aux_reg(ARC_REG_PCT_CONTROL, (tmp & 0xffff0000) | 0x0);
}
/*
* Assigns hardware counter to hardware condition.
* Note that there is no separate start/stop mechanism;
* stopping is achieved by assigning the 'never' condition
*/
static void arc_pmu_start(struct perf_event *event, int flags)
{
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));
event->hw.state = 0;
/* enable ARC pmu here */
write_aux_reg(ARC_REG_PCT_INDEX, idx);
write_aux_reg(ARC_REG_PCT_CONFIG, hwc->config);
}
static void arc_pmu_stop(struct perf_event *event, int flags)
{
struct hw_perf_event *hwc = &event->hw;
int idx = hwc->idx;
if (!(event->hw.state & PERF_HES_STOPPED)) {
/* stop ARC pmu here */
write_aux_reg(ARC_REG_PCT_INDEX, idx);
/* condition code #0 is always "never" */
write_aux_reg(ARC_REG_PCT_CONFIG, 0);
event->hw.state |= PERF_HES_STOPPED;
}
if ((flags & PERF_EF_UPDATE) &&
!(event->hw.state & PERF_HES_UPTODATE)) {
arc_perf_event_update(event, &event->hw, idx);
event->hw.state |= PERF_HES_UPTODATE;
}
}
static void arc_pmu_del(struct perf_event *event, int flags)
{
struct arc_pmu *arc_pmu = container_of(event->pmu, struct arc_pmu, pmu);
arc_pmu_stop(event, PERF_EF_UPDATE);
__clear_bit(event->hw.idx, arc_pmu->used_mask);
perf_event_update_userpage(event);
}
/* allocate hardware counter and optionally start counting */
static int arc_pmu_add(struct perf_event *event, int flags)
{
struct arc_pmu *arc_pmu = container_of(event->pmu, struct arc_pmu, pmu);
struct hw_perf_event *hwc = &event->hw;
int idx = hwc->idx;
if (__test_and_set_bit(idx, arc_pmu->used_mask)) {
idx = find_first_zero_bit(arc_pmu->used_mask,
arc_pmu->n_counters);
if (idx == arc_pmu->n_counters)
return -EAGAIN;
__set_bit(idx, arc_pmu->used_mask);
hwc->idx = idx;
}
write_aux_reg(ARC_REG_PCT_INDEX, idx);
write_aux_reg(ARC_REG_PCT_CONFIG, 0);
write_aux_reg(ARC_REG_PCT_COUNTL, 0);
write_aux_reg(ARC_REG_PCT_COUNTH, 0);
local64_set(&hwc->prev_count, 0);
hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
if (flags & PERF_EF_START)
arc_pmu_start(event, PERF_EF_RELOAD);
perf_event_update_userpage(event);
return 0;
}
static int arc_pmu_device_probe(struct platform_device *pdev)
{
struct arc_pmu *arc_pmu;
struct arc_reg_pct_build pct_bcr;
struct arc_reg_cc_build cc_bcr;
int i, j, ret;
union cc_name {
struct {
uint32_t word0, word1;
char sentinel;
} indiv;
char str[9];
} cc_name;
READ_BCR(ARC_REG_PCT_BUILD, pct_bcr);
if (!pct_bcr.v) {
pr_err("This core does not have performance counters!\n");
return -ENODEV;
}
arc_pmu = devm_kzalloc(&pdev->dev, sizeof(struct arc_pmu),
GFP_KERNEL);
if (!arc_pmu)
return -ENOMEM;
arc_pmu->n_counters = pct_bcr.c;
BUG_ON(arc_pmu->n_counters > ARC_PMU_MAX_HWEVENTS);
arc_pmu->counter_size = 32 + (pct_bcr.s << 4);
pr_info("ARC PMU found with %d counters of size %d bits\n",
arc_pmu->n_counters, arc_pmu->counter_size);
READ_BCR(ARC_REG_CC_BUILD, cc_bcr);
if (!cc_bcr.v)
pr_err("Strange! Performance counters exist, but no countable conditions?\n");
pr_info("ARC PMU has %d countable conditions\n", cc_bcr.c);
cc_name.str[8] = 0;
for (i = 0; i < PERF_COUNT_HW_MAX; i++)
arc_pmu->ev_hw_idx[i] = -1;
for (j = 0; j < cc_bcr.c; j++) {
write_aux_reg(ARC_REG_CC_INDEX, j);
cc_name.indiv.word0 = read_aux_reg(ARC_REG_CC_NAME0);
cc_name.indiv.word1 = read_aux_reg(ARC_REG_CC_NAME1);
for (i = 0; i < ARRAY_SIZE(arc_pmu_ev_hw_map); i++) {
if (arc_pmu_ev_hw_map[i] &&
!strcmp(arc_pmu_ev_hw_map[i], cc_name.str) &&
strlen(arc_pmu_ev_hw_map[i])) {
pr_debug("mapping %d to idx %d with name %s\n",
i, j, cc_name.str);
arc_pmu->ev_hw_idx[i] = j;
}
}
}
arc_pmu->pmu = (struct pmu) {
.pmu_enable = arc_pmu_enable,
.pmu_disable = arc_pmu_disable,
.event_init = arc_pmu_event_init,
.add = arc_pmu_add,
.del = arc_pmu_del,
.start = arc_pmu_start,
.stop = arc_pmu_stop,
.read = arc_pmu_read,
};
ret = perf_pmu_register(&arc_pmu->pmu, pdev->name, PERF_TYPE_RAW);
return ret;
}
#ifdef CONFIG_OF
static const struct of_device_id arc_pmu_match[] = {
{ .compatible = "snps,arc700-pmu" },
{},
};
MODULE_DEVICE_TABLE(of, arc_pmu_match);
#endif
static struct platform_driver arc_pmu_driver = {
.driver = {
.name = "arc700-pmu",
.of_match_table = of_match_ptr(arc_pmu_match),
},
.probe = arc_pmu_device_probe,
};
module_platform_driver(arc_pmu_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Mischa Jonker <mjonker@synopsys.com>");
MODULE_DESCRIPTION("ARC PMU driver");
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