blob: a78a879e7ef1cc60199c511f94e9bbfc839c5c67 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2008-2017 Andes Technology Corporation
*
* Reference ARMv7: Jean Pihet <jpihet@mvista.com>
* 2010 (c) MontaVista Software, LLC.
*/
#include <linux/perf_event.h>
#include <linux/bitmap.h>
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/pm_runtime.h>
#include <linux/ftrace.h>
#include <linux/uaccess.h>
#include <linux/sched/clock.h>
#include <linux/percpu-defs.h>
#include <asm/pmu.h>
#include <asm/irq_regs.h>
#include <asm/nds32.h>
#include <asm/stacktrace.h>
#include <asm/perf_event.h>
#include <nds32_intrinsic.h>
/* Set at runtime when we know what CPU type we are. */
static struct nds32_pmu *cpu_pmu;
static DEFINE_PER_CPU(struct pmu_hw_events, cpu_hw_events);
static void nds32_pmu_start(struct nds32_pmu *cpu_pmu);
static void nds32_pmu_stop(struct nds32_pmu *cpu_pmu);
static struct platform_device_id cpu_pmu_plat_device_ids[] = {
{.name = "nds32-pfm"},
{},
};
static int nds32_pmu_map_cache_event(const unsigned int (*cache_map)
[PERF_COUNT_HW_CACHE_MAX]
[PERF_COUNT_HW_CACHE_OP_MAX]
[PERF_COUNT_HW_CACHE_RESULT_MAX], u64 config)
{
unsigned int cache_type, cache_op, cache_result, ret;
cache_type = (config >> 0) & 0xff;
if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
return -EINVAL;
cache_op = (config >> 8) & 0xff;
if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
return -EINVAL;
cache_result = (config >> 16) & 0xff;
if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
return -EINVAL;
ret = (int)(*cache_map)[cache_type][cache_op][cache_result];
if (ret == CACHE_OP_UNSUPPORTED)
return -ENOENT;
return ret;
}
static int
nds32_pmu_map_hw_event(const unsigned int (*event_map)[PERF_COUNT_HW_MAX],
u64 config)
{
int mapping;
if (config >= PERF_COUNT_HW_MAX)
return -ENOENT;
mapping = (*event_map)[config];
return mapping == HW_OP_UNSUPPORTED ? -ENOENT : mapping;
}
static int nds32_pmu_map_raw_event(u32 raw_event_mask, u64 config)
{
int ev_type = (int)(config & raw_event_mask);
int idx = config >> 8;
switch (idx) {
case 0:
ev_type = PFM_OFFSET_MAGIC_0 + ev_type;
if (ev_type >= SPAV3_0_SEL_LAST || ev_type <= SPAV3_0_SEL_BASE)
return -ENOENT;
break;
case 1:
ev_type = PFM_OFFSET_MAGIC_1 + ev_type;
if (ev_type >= SPAV3_1_SEL_LAST || ev_type <= SPAV3_1_SEL_BASE)
return -ENOENT;
break;
case 2:
ev_type = PFM_OFFSET_MAGIC_2 + ev_type;
if (ev_type >= SPAV3_2_SEL_LAST || ev_type <= SPAV3_2_SEL_BASE)
return -ENOENT;
break;
default:
return -ENOENT;
}
return ev_type;
}
int
nds32_pmu_map_event(struct perf_event *event,
const unsigned int (*event_map)[PERF_COUNT_HW_MAX],
const unsigned int (*cache_map)
[PERF_COUNT_HW_CACHE_MAX]
[PERF_COUNT_HW_CACHE_OP_MAX]
[PERF_COUNT_HW_CACHE_RESULT_MAX], u32 raw_event_mask)
{
u64 config = event->attr.config;
switch (event->attr.type) {
case PERF_TYPE_HARDWARE:
return nds32_pmu_map_hw_event(event_map, config);
case PERF_TYPE_HW_CACHE:
return nds32_pmu_map_cache_event(cache_map, config);
case PERF_TYPE_RAW:
return nds32_pmu_map_raw_event(raw_event_mask, config);
}
return -ENOENT;
}
static int nds32_spav3_map_event(struct perf_event *event)
{
return nds32_pmu_map_event(event, &nds32_pfm_perf_map,
&nds32_pfm_perf_cache_map, SOFTWARE_EVENT_MASK);
}
static inline u32 nds32_pfm_getreset_flags(void)
{
/* Read overflow status */
u32 val = __nds32__mfsr(NDS32_SR_PFM_CTL);
u32 old_val = val;
/* Write overflow bit to clear status, and others keep it 0 */
u32 ov_flag = PFM_CTL_OVF[0] | PFM_CTL_OVF[1] | PFM_CTL_OVF[2];
__nds32__mtsr(val | ov_flag, NDS32_SR_PFM_CTL);
return old_val;
}
static inline int nds32_pfm_has_overflowed(u32 pfm)
{
u32 ov_flag = PFM_CTL_OVF[0] | PFM_CTL_OVF[1] | PFM_CTL_OVF[2];
return pfm & ov_flag;
}
static inline int nds32_pfm_counter_has_overflowed(u32 pfm, int idx)
{
u32 mask = 0;
switch (idx) {
case 0:
mask = PFM_CTL_OVF[0];
break;
case 1:
mask = PFM_CTL_OVF[1];
break;
case 2:
mask = PFM_CTL_OVF[2];
break;
default:
pr_err("%s index wrong\n", __func__);
break;
}
return pfm & mask;
}
/*
* Set the next IRQ period, based on the hwc->period_left value.
* To be called with the event disabled in hw:
*/
int nds32_pmu_event_set_period(struct perf_event *event)
{
struct nds32_pmu *nds32_pmu = to_nds32_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
s64 left = local64_read(&hwc->period_left);
s64 period = hwc->sample_period;
int ret = 0;
/* The period may have been changed by PERF_EVENT_IOC_PERIOD */
if (unlikely(period != hwc->last_period))
left = period - (hwc->last_period - left);
if (unlikely(left <= -period)) {
left = period;
local64_set(&hwc->period_left, left);
hwc->last_period = period;
ret = 1;
}
if (unlikely(left <= 0)) {
left += period;
local64_set(&hwc->period_left, left);
hwc->last_period = period;
ret = 1;
}
if (left > (s64)nds32_pmu->max_period)
left = nds32_pmu->max_period;
/*
* The hw event starts counting from this event offset,
* mark it to be able to extract future "deltas":
*/
local64_set(&hwc->prev_count, (u64)(-left));
nds32_pmu->write_counter(event, (u64)(-left) & nds32_pmu->max_period);
perf_event_update_userpage(event);
return ret;
}
static irqreturn_t nds32_pmu_handle_irq(int irq_num, void *dev)
{
u32 pfm;
struct perf_sample_data data;
struct nds32_pmu *cpu_pmu = (struct nds32_pmu *)dev;
struct pmu_hw_events *cpuc = cpu_pmu->get_hw_events();
struct pt_regs *regs;
int idx;
/*
* Get and reset the IRQ flags
*/
pfm = nds32_pfm_getreset_flags();
/*
* Did an overflow occur?
*/
if (!nds32_pfm_has_overflowed(pfm))
return IRQ_NONE;
/*
* Handle the counter(s) overflow(s)
*/
regs = get_irq_regs();
nds32_pmu_stop(cpu_pmu);
for (idx = 0; idx < cpu_pmu->num_events; ++idx) {
struct perf_event *event = cpuc->events[idx];
struct hw_perf_event *hwc;
/* Ignore if we don't have an event. */
if (!event)
continue;
/*
* We have a single interrupt for all counters. Check that
* each counter has overflowed before we process it.
*/
if (!nds32_pfm_counter_has_overflowed(pfm, idx))
continue;
hwc = &event->hw;
nds32_pmu_event_update(event);
perf_sample_data_init(&data, 0, hwc->last_period);
if (!nds32_pmu_event_set_period(event))
continue;
if (perf_event_overflow(event, &data, regs))
cpu_pmu->disable(event);
}
nds32_pmu_start(cpu_pmu);
/*
* Handle the pending perf events.
*
* Note: this call *must* be run with interrupts disabled. For
* platforms that can have the PMU interrupts raised as an NMI, this
* will not work.
*/
irq_work_run();
return IRQ_HANDLED;
}
static inline int nds32_pfm_counter_valid(struct nds32_pmu *cpu_pmu, int idx)
{
return ((idx >= 0) && (idx < cpu_pmu->num_events));
}
static inline int nds32_pfm_disable_counter(int idx)
{
unsigned int val = __nds32__mfsr(NDS32_SR_PFM_CTL);
u32 mask = 0;
mask = PFM_CTL_EN[idx];
val &= ~mask;
val &= ~(PFM_CTL_OVF[0] | PFM_CTL_OVF[1] | PFM_CTL_OVF[2]);
__nds32__mtsr_isb(val, NDS32_SR_PFM_CTL);
return idx;
}
/*
* Add an event filter to a given event.
*/
static int nds32_pmu_set_event_filter(struct hw_perf_event *event,
struct perf_event_attr *attr)
{
unsigned long config_base = 0;
int idx = event->idx;
unsigned long no_kernel_tracing = 0;
unsigned long no_user_tracing = 0;
/* If index is -1, do not do anything */
if (idx == -1)
return 0;
no_kernel_tracing = PFM_CTL_KS[idx];
no_user_tracing = PFM_CTL_KU[idx];
/*
* Default: enable both kernel and user mode tracing.
*/
if (attr->exclude_user)
config_base |= no_user_tracing;
if (attr->exclude_kernel)
config_base |= no_kernel_tracing;
/*
* Install the filter into config_base as this is used to
* construct the event type.
*/
event->config_base |= config_base;
return 0;
}
static inline void nds32_pfm_write_evtsel(int idx, u32 evnum)
{
u32 offset = 0;
u32 ori_val = __nds32__mfsr(NDS32_SR_PFM_CTL);
u32 ev_mask = 0;
u32 no_kernel_mask = 0;
u32 no_user_mask = 0;
u32 val;
offset = PFM_CTL_OFFSEL[idx];
/* Clear previous mode selection, and write new one */
no_kernel_mask = PFM_CTL_KS[idx];
no_user_mask = PFM_CTL_KU[idx];
ori_val &= ~no_kernel_mask;
ori_val &= ~no_user_mask;
if (evnum & no_kernel_mask)
ori_val |= no_kernel_mask;
if (evnum & no_user_mask)
ori_val |= no_user_mask;
/* Clear previous event selection */
ev_mask = PFM_CTL_SEL[idx];
ori_val &= ~ev_mask;
evnum &= SOFTWARE_EVENT_MASK;
/* undo the linear mapping */
evnum = get_converted_evet_hw_num(evnum);
val = ori_val | (evnum << offset);
val &= ~(PFM_CTL_OVF[0] | PFM_CTL_OVF[1] | PFM_CTL_OVF[2]);
__nds32__mtsr_isb(val, NDS32_SR_PFM_CTL);
}
static inline int nds32_pfm_enable_counter(int idx)
{
unsigned int val = __nds32__mfsr(NDS32_SR_PFM_CTL);
u32 mask = 0;
mask = PFM_CTL_EN[idx];
val |= mask;
val &= ~(PFM_CTL_OVF[0] | PFM_CTL_OVF[1] | PFM_CTL_OVF[2]);
__nds32__mtsr_isb(val, NDS32_SR_PFM_CTL);
return idx;
}
static inline int nds32_pfm_enable_intens(int idx)
{
unsigned int val = __nds32__mfsr(NDS32_SR_PFM_CTL);
u32 mask = 0;
mask = PFM_CTL_IE[idx];
val |= mask;
val &= ~(PFM_CTL_OVF[0] | PFM_CTL_OVF[1] | PFM_CTL_OVF[2]);
__nds32__mtsr_isb(val, NDS32_SR_PFM_CTL);
return idx;
}
static inline int nds32_pfm_disable_intens(int idx)
{
unsigned int val = __nds32__mfsr(NDS32_SR_PFM_CTL);
u32 mask = 0;
mask = PFM_CTL_IE[idx];
val &= ~mask;
val &= ~(PFM_CTL_OVF[0] | PFM_CTL_OVF[1] | PFM_CTL_OVF[2]);
__nds32__mtsr_isb(val, NDS32_SR_PFM_CTL);
return idx;
}
static int event_requires_mode_exclusion(struct perf_event_attr *attr)
{
/* Other modes NDS32 does not support */
return attr->exclude_user || attr->exclude_kernel;
}
static void nds32_pmu_enable_event(struct perf_event *event)
{
unsigned long flags;
unsigned int evnum = 0;
struct hw_perf_event *hwc = &event->hw;
struct nds32_pmu *cpu_pmu = to_nds32_pmu(event->pmu);
struct pmu_hw_events *events = cpu_pmu->get_hw_events();
int idx = hwc->idx;
if (!nds32_pfm_counter_valid(cpu_pmu, idx)) {
pr_err("CPU enabling wrong pfm counter IRQ enable\n");
return;
}
/*
* Enable counter and interrupt, and set the counter to count
* the event that we're interested in.
*/
raw_spin_lock_irqsave(&events->pmu_lock, flags);
/*
* Disable counter
*/
nds32_pfm_disable_counter(idx);
/*
* Check whether we need to exclude the counter from certain modes.
*/
if ((!cpu_pmu->set_event_filter ||
cpu_pmu->set_event_filter(hwc, &event->attr)) &&
event_requires_mode_exclusion(&event->attr)) {
pr_notice
("NDS32 performance counters do not support mode exclusion\n");
hwc->config_base = 0;
}
/* Write event */
evnum = hwc->config_base;
nds32_pfm_write_evtsel(idx, evnum);
/*
* Enable interrupt for this counter
*/
nds32_pfm_enable_intens(idx);
/*
* Enable counter
*/
nds32_pfm_enable_counter(idx);
raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
}
static void nds32_pmu_disable_event(struct perf_event *event)
{
unsigned long flags;
struct hw_perf_event *hwc = &event->hw;
struct nds32_pmu *cpu_pmu = to_nds32_pmu(event->pmu);
struct pmu_hw_events *events = cpu_pmu->get_hw_events();
int idx = hwc->idx;
if (!nds32_pfm_counter_valid(cpu_pmu, idx)) {
pr_err("CPU disabling wrong pfm counter IRQ enable %d\n", idx);
return;
}
/*
* Disable counter and interrupt
*/
raw_spin_lock_irqsave(&events->pmu_lock, flags);
/*
* Disable counter
*/
nds32_pfm_disable_counter(idx);
/*
* Disable interrupt for this counter
*/
nds32_pfm_disable_intens(idx);
raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
}
static inline u32 nds32_pmu_read_counter(struct perf_event *event)
{
struct nds32_pmu *cpu_pmu = to_nds32_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
int idx = hwc->idx;
u32 count = 0;
if (!nds32_pfm_counter_valid(cpu_pmu, idx)) {
pr_err("CPU reading wrong counter %d\n", idx);
} else {
switch (idx) {
case PFMC0:
count = __nds32__mfsr(NDS32_SR_PFMC0);
break;
case PFMC1:
count = __nds32__mfsr(NDS32_SR_PFMC1);
break;
case PFMC2:
count = __nds32__mfsr(NDS32_SR_PFMC2);
break;
default:
pr_err
("%s: CPU has no performance counters %d\n",
__func__, idx);
}
}
return count;
}
static inline void nds32_pmu_write_counter(struct perf_event *event, u32 value)
{
struct nds32_pmu *cpu_pmu = to_nds32_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
int idx = hwc->idx;
if (!nds32_pfm_counter_valid(cpu_pmu, idx)) {
pr_err("CPU writing wrong counter %d\n", idx);
} else {
switch (idx) {
case PFMC0:
__nds32__mtsr_isb(value, NDS32_SR_PFMC0);
break;
case PFMC1:
__nds32__mtsr_isb(value, NDS32_SR_PFMC1);
break;
case PFMC2:
__nds32__mtsr_isb(value, NDS32_SR_PFMC2);
break;
default:
pr_err
("%s: CPU has no performance counters %d\n",
__func__, idx);
}
}
}
static int nds32_pmu_get_event_idx(struct pmu_hw_events *cpuc,
struct perf_event *event)
{
int idx;
struct hw_perf_event *hwc = &event->hw;
/*
* Current implementation maps cycles, instruction count and cache-miss
* to specific counter.
* However, multiple of the 3 counters are able to count these events.
*
*
* SOFTWARE_EVENT_MASK mask for getting event num ,
* This is defined by Jia-Rung, you can change the polocies.
* However, do not exceed 8 bits. This is hardware specific.
* The last number is SPAv3_2_SEL_LAST.
*/
unsigned long evtype = hwc->config_base & SOFTWARE_EVENT_MASK;
idx = get_converted_event_idx(evtype);
/*
* Try to get the counter for correpsonding event
*/
if (evtype == SPAV3_0_SEL_TOTAL_CYCLES) {
if (!test_and_set_bit(idx, cpuc->used_mask))
return idx;
if (!test_and_set_bit(NDS32_IDX_COUNTER0, cpuc->used_mask))
return NDS32_IDX_COUNTER0;
if (!test_and_set_bit(NDS32_IDX_COUNTER1, cpuc->used_mask))
return NDS32_IDX_COUNTER1;
} else if (evtype == SPAV3_1_SEL_COMPLETED_INSTRUCTION) {
if (!test_and_set_bit(idx, cpuc->used_mask))
return idx;
else if (!test_and_set_bit(NDS32_IDX_COUNTER1, cpuc->used_mask))
return NDS32_IDX_COUNTER1;
else if (!test_and_set_bit
(NDS32_IDX_CYCLE_COUNTER, cpuc->used_mask))
return NDS32_IDX_CYCLE_COUNTER;
} else {
if (!test_and_set_bit(idx, cpuc->used_mask))
return idx;
}
return -EAGAIN;
}
static void nds32_pmu_start(struct nds32_pmu *cpu_pmu)
{
unsigned long flags;
unsigned int val;
struct pmu_hw_events *events = cpu_pmu->get_hw_events();
raw_spin_lock_irqsave(&events->pmu_lock, flags);
/* Enable all counters , NDS PFM has 3 counters */
val = __nds32__mfsr(NDS32_SR_PFM_CTL);
val |= (PFM_CTL_EN[0] | PFM_CTL_EN[1] | PFM_CTL_EN[2]);
val &= ~(PFM_CTL_OVF[0] | PFM_CTL_OVF[1] | PFM_CTL_OVF[2]);
__nds32__mtsr_isb(val, NDS32_SR_PFM_CTL);
raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
}
static void nds32_pmu_stop(struct nds32_pmu *cpu_pmu)
{
unsigned long flags;
unsigned int val;
struct pmu_hw_events *events = cpu_pmu->get_hw_events();
raw_spin_lock_irqsave(&events->pmu_lock, flags);
/* Disable all counters , NDS PFM has 3 counters */
val = __nds32__mfsr(NDS32_SR_PFM_CTL);
val &= ~(PFM_CTL_EN[0] | PFM_CTL_EN[1] | PFM_CTL_EN[2]);
val &= ~(PFM_CTL_OVF[0] | PFM_CTL_OVF[1] | PFM_CTL_OVF[2]);
__nds32__mtsr_isb(val, NDS32_SR_PFM_CTL);
raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
}
static void nds32_pmu_reset(void *info)
{
u32 val = 0;
val |= (PFM_CTL_OVF[0] | PFM_CTL_OVF[1] | PFM_CTL_OVF[2]);
__nds32__mtsr(val, NDS32_SR_PFM_CTL);
__nds32__mtsr(0, NDS32_SR_PFM_CTL);
__nds32__mtsr(0, NDS32_SR_PFMC0);
__nds32__mtsr(0, NDS32_SR_PFMC1);
__nds32__mtsr(0, NDS32_SR_PFMC2);
}
static void nds32_pmu_init(struct nds32_pmu *cpu_pmu)
{
cpu_pmu->handle_irq = nds32_pmu_handle_irq;
cpu_pmu->enable = nds32_pmu_enable_event;
cpu_pmu->disable = nds32_pmu_disable_event;
cpu_pmu->read_counter = nds32_pmu_read_counter;
cpu_pmu->write_counter = nds32_pmu_write_counter;
cpu_pmu->get_event_idx = nds32_pmu_get_event_idx;
cpu_pmu->start = nds32_pmu_start;
cpu_pmu->stop = nds32_pmu_stop;
cpu_pmu->reset = nds32_pmu_reset;
cpu_pmu->max_period = 0xFFFFFFFF; /* Maximum counts */
};
static u32 nds32_read_num_pfm_events(void)
{
/* NDS32 SPAv3 PMU support 3 counter */
return 3;
}
static int device_pmu_init(struct nds32_pmu *cpu_pmu)
{
nds32_pmu_init(cpu_pmu);
/*
* This name should be devive-specific name, whatever you like :)
* I think "PMU" will be a good generic name.
*/
cpu_pmu->name = "nds32v3-pmu";
cpu_pmu->map_event = nds32_spav3_map_event;
cpu_pmu->num_events = nds32_read_num_pfm_events();
cpu_pmu->set_event_filter = nds32_pmu_set_event_filter;
return 0;
}
/*
* CPU PMU identification and probing.
*/
static int probe_current_pmu(struct nds32_pmu *pmu)
{
int ret;
get_cpu();
ret = -ENODEV;
/*
* If ther are various CPU types with its own PMU, initialize with
*
* the corresponding one
*/
device_pmu_init(pmu);
put_cpu();
return ret;
}
static void nds32_pmu_enable(struct pmu *pmu)
{
struct nds32_pmu *nds32_pmu = to_nds32_pmu(pmu);
struct pmu_hw_events *hw_events = nds32_pmu->get_hw_events();
int enabled = bitmap_weight(hw_events->used_mask,
nds32_pmu->num_events);
if (enabled)
nds32_pmu->start(nds32_pmu);
}
static void nds32_pmu_disable(struct pmu *pmu)
{
struct nds32_pmu *nds32_pmu = to_nds32_pmu(pmu);
nds32_pmu->stop(nds32_pmu);
}
static void nds32_pmu_release_hardware(struct nds32_pmu *nds32_pmu)
{
nds32_pmu->free_irq(nds32_pmu);
pm_runtime_put_sync(&nds32_pmu->plat_device->dev);
}
static irqreturn_t nds32_pmu_dispatch_irq(int irq, void *dev)
{
struct nds32_pmu *nds32_pmu = (struct nds32_pmu *)dev;
int ret;
u64 start_clock, finish_clock;
start_clock = local_clock();
ret = nds32_pmu->handle_irq(irq, dev);
finish_clock = local_clock();
perf_sample_event_took(finish_clock - start_clock);
return ret;
}
static int nds32_pmu_reserve_hardware(struct nds32_pmu *nds32_pmu)
{
int err;
struct platform_device *pmu_device = nds32_pmu->plat_device;
if (!pmu_device)
return -ENODEV;
pm_runtime_get_sync(&pmu_device->dev);
err = nds32_pmu->request_irq(nds32_pmu, nds32_pmu_dispatch_irq);
if (err) {
nds32_pmu_release_hardware(nds32_pmu);
return err;
}
return 0;
}
static int
validate_event(struct pmu *pmu, struct pmu_hw_events *hw_events,
struct perf_event *event)
{
struct nds32_pmu *nds32_pmu = to_nds32_pmu(event->pmu);
if (is_software_event(event))
return 1;
if (event->pmu != pmu)
return 0;
if (event->state < PERF_EVENT_STATE_OFF)
return 1;
if (event->state == PERF_EVENT_STATE_OFF && !event->attr.enable_on_exec)
return 1;
return nds32_pmu->get_event_idx(hw_events, event) >= 0;
}
static int validate_group(struct perf_event *event)
{
struct perf_event *sibling, *leader = event->group_leader;
struct pmu_hw_events fake_pmu;
DECLARE_BITMAP(fake_used_mask, MAX_COUNTERS);
/*
* Initialize the fake PMU. We only need to populate the
* used_mask for the purposes of validation.
*/
memset(fake_used_mask, 0, sizeof(fake_used_mask));
if (!validate_event(event->pmu, &fake_pmu, leader))
return -EINVAL;
for_each_sibling_event(sibling, leader) {
if (!validate_event(event->pmu, &fake_pmu, sibling))
return -EINVAL;
}
if (!validate_event(event->pmu, &fake_pmu, event))
return -EINVAL;
return 0;
}
static int __hw_perf_event_init(struct perf_event *event)
{
struct nds32_pmu *nds32_pmu = to_nds32_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
int mapping;
mapping = nds32_pmu->map_event(event);
if (mapping < 0) {
pr_debug("event %x:%llx not supported\n", event->attr.type,
event->attr.config);
return mapping;
}
/*
* We don't assign an index until we actually place the event onto
* hardware. Use -1 to signify that we haven't decided where to put it
* yet. For SMP systems, each core has it's own PMU so we can't do any
* clever allocation or constraints checking at this point.
*/
hwc->idx = -1;
hwc->config_base = 0;
hwc->config = 0;
hwc->event_base = 0;
/*
* Check whether we need to exclude the counter from certain modes.
*/
if ((!nds32_pmu->set_event_filter ||
nds32_pmu->set_event_filter(hwc, &event->attr)) &&
event_requires_mode_exclusion(&event->attr)) {
pr_debug
("NDS performance counters do not support mode exclusion\n");
return -EOPNOTSUPP;
}
/*
* Store the event encoding into the config_base field.
*/
hwc->config_base |= (unsigned long)mapping;
if (!hwc->sample_period) {
/*
* For non-sampling runs, limit the sample_period to half
* of the counter width. That way, the new counter value
* is far less likely to overtake the previous one unless
* you have some serious IRQ latency issues.
*/
hwc->sample_period = nds32_pmu->max_period >> 1;
hwc->last_period = hwc->sample_period;
local64_set(&hwc->period_left, hwc->sample_period);
}
if (event->group_leader != event) {
if (validate_group(event) != 0)
return -EINVAL;
}
return 0;
}
static int nds32_pmu_event_init(struct perf_event *event)
{
struct nds32_pmu *nds32_pmu = to_nds32_pmu(event->pmu);
int err = 0;
atomic_t *active_events = &nds32_pmu->active_events;
/* does not support taken branch sampling */
if (has_branch_stack(event))
return -EOPNOTSUPP;
if (nds32_pmu->map_event(event) == -ENOENT)
return -ENOENT;
if (!atomic_inc_not_zero(active_events)) {
if (atomic_read(active_events) == 0) {
/* Register irq handler */
err = nds32_pmu_reserve_hardware(nds32_pmu);
}
if (!err)
atomic_inc(active_events);
}
if (err)
return err;
err = __hw_perf_event_init(event);
return err;
}
static void nds32_start(struct perf_event *event, int flags)
{
struct nds32_pmu *nds32_pmu = to_nds32_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
/*
* NDS pmu always has to reprogram the period, so ignore
* PERF_EF_RELOAD, see the comment below.
*/
if (flags & PERF_EF_RELOAD)
WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
hwc->state = 0;
/* Set the period for the event. */
nds32_pmu_event_set_period(event);
nds32_pmu->enable(event);
}
static int nds32_pmu_add(struct perf_event *event, int flags)
{
struct nds32_pmu *nds32_pmu = to_nds32_pmu(event->pmu);
struct pmu_hw_events *hw_events = nds32_pmu->get_hw_events();
struct hw_perf_event *hwc = &event->hw;
int idx;
int err = 0;
perf_pmu_disable(event->pmu);
/* If we don't have a space for the counter then finish early. */
idx = nds32_pmu->get_event_idx(hw_events, event);
if (idx < 0) {
err = idx;
goto out;
}
/*
* If there is an event in the counter we are going to use then make
* sure it is disabled.
*/
event->hw.idx = idx;
nds32_pmu->disable(event);
hw_events->events[idx] = event;
hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
if (flags & PERF_EF_START)
nds32_start(event, PERF_EF_RELOAD);
/* Propagate our changes to the userspace mapping. */
perf_event_update_userpage(event);
out:
perf_pmu_enable(event->pmu);
return err;
}
u64 nds32_pmu_event_update(struct perf_event *event)
{
struct nds32_pmu *nds32_pmu = to_nds32_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
u64 delta, prev_raw_count, new_raw_count;
again:
prev_raw_count = local64_read(&hwc->prev_count);
new_raw_count = nds32_pmu->read_counter(event);
if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
new_raw_count) != prev_raw_count) {
goto again;
}
/*
* Whether overflow or not, "unsigned substraction"
* will always get their delta
*/
delta = (new_raw_count - prev_raw_count) & nds32_pmu->max_period;
local64_add(delta, &event->count);
local64_sub(delta, &hwc->period_left);
return new_raw_count;
}
static void nds32_stop(struct perf_event *event, int flags)
{
struct nds32_pmu *nds32_pmu = to_nds32_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
/*
* NDS pmu always has to update the counter, so ignore
* PERF_EF_UPDATE, see comments in nds32_start().
*/
if (!(hwc->state & PERF_HES_STOPPED)) {
nds32_pmu->disable(event);
nds32_pmu_event_update(event);
hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
}
}
static void nds32_pmu_del(struct perf_event *event, int flags)
{
struct nds32_pmu *nds32_pmu = to_nds32_pmu(event->pmu);
struct pmu_hw_events *hw_events = nds32_pmu->get_hw_events();
struct hw_perf_event *hwc = &event->hw;
int idx = hwc->idx;
nds32_stop(event, PERF_EF_UPDATE);
hw_events->events[idx] = NULL;
clear_bit(idx, hw_events->used_mask);
perf_event_update_userpage(event);
}
static void nds32_pmu_read(struct perf_event *event)
{
nds32_pmu_event_update(event);
}
/* Please refer to SPAv3 for more hardware specific details */
PMU_FORMAT_ATTR(event, "config:0-63");
static struct attribute *nds32_arch_formats_attr[] = {
&format_attr_event.attr,
NULL,
};
static struct attribute_group nds32_pmu_format_group = {
.name = "format",
.attrs = nds32_arch_formats_attr,
};
static ssize_t nds32_pmu_cpumask_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
return 0;
}
static DEVICE_ATTR(cpus, 0444, nds32_pmu_cpumask_show, NULL);
static struct attribute *nds32_pmu_common_attrs[] = {
&dev_attr_cpus.attr,
NULL,
};
static struct attribute_group nds32_pmu_common_group = {
.attrs = nds32_pmu_common_attrs,
};
static const struct attribute_group *nds32_pmu_attr_groups[] = {
&nds32_pmu_format_group,
&nds32_pmu_common_group,
NULL,
};
static void nds32_init(struct nds32_pmu *nds32_pmu)
{
atomic_set(&nds32_pmu->active_events, 0);
nds32_pmu->pmu = (struct pmu) {
.pmu_enable = nds32_pmu_enable,
.pmu_disable = nds32_pmu_disable,
.attr_groups = nds32_pmu_attr_groups,
.event_init = nds32_pmu_event_init,
.add = nds32_pmu_add,
.del = nds32_pmu_del,
.start = nds32_start,
.stop = nds32_stop,
.read = nds32_pmu_read,
};
}
int nds32_pmu_register(struct nds32_pmu *nds32_pmu, int type)
{
nds32_init(nds32_pmu);
pm_runtime_enable(&nds32_pmu->plat_device->dev);
pr_info("enabled with %s PMU driver, %d counters available\n",
nds32_pmu->name, nds32_pmu->num_events);
return perf_pmu_register(&nds32_pmu->pmu, nds32_pmu->name, type);
}
static struct pmu_hw_events *cpu_pmu_get_cpu_events(void)
{
return this_cpu_ptr(&cpu_hw_events);
}
static int cpu_pmu_request_irq(struct nds32_pmu *cpu_pmu, irq_handler_t handler)
{
int err, irq, irqs;
struct platform_device *pmu_device = cpu_pmu->plat_device;
if (!pmu_device)
return -ENODEV;
irqs = min(pmu_device->num_resources, num_possible_cpus());
if (irqs < 1) {
pr_err("no irqs for PMUs defined\n");
return -ENODEV;
}
irq = platform_get_irq(pmu_device, 0);
err = request_irq(irq, handler, IRQF_NOBALANCING, "nds32-pfm",
cpu_pmu);
if (err) {
pr_err("unable to request IRQ%d for NDS PMU counters\n",
irq);
return err;
}
return 0;
}
static void cpu_pmu_free_irq(struct nds32_pmu *cpu_pmu)
{
int irq;
struct platform_device *pmu_device = cpu_pmu->plat_device;
irq = platform_get_irq(pmu_device, 0);
if (irq >= 0)
free_irq(irq, cpu_pmu);
}
static void cpu_pmu_init(struct nds32_pmu *cpu_pmu)
{
int cpu;
struct pmu_hw_events *events = &per_cpu(cpu_hw_events, cpu);
raw_spin_lock_init(&events->pmu_lock);
cpu_pmu->get_hw_events = cpu_pmu_get_cpu_events;
cpu_pmu->request_irq = cpu_pmu_request_irq;
cpu_pmu->free_irq = cpu_pmu_free_irq;
/* Ensure the PMU has sane values out of reset. */
if (cpu_pmu->reset)
on_each_cpu(cpu_pmu->reset, cpu_pmu, 1);
}
static const struct of_device_id cpu_pmu_of_device_ids[] = {
{.compatible = "andestech,nds32v3-pmu",
.data = device_pmu_init},
{},
};
static int cpu_pmu_device_probe(struct platform_device *pdev)
{
const struct of_device_id *of_id;
int (*init_fn)(struct nds32_pmu *nds32_pmu);
struct device_node *node = pdev->dev.of_node;
struct nds32_pmu *pmu;
int ret = -ENODEV;
if (cpu_pmu) {
pr_notice("[perf] attempt to register multiple PMU devices!\n");
return -ENOSPC;
}
pmu = kzalloc(sizeof(*pmu), GFP_KERNEL);
if (!pmu)
return -ENOMEM;
of_id = of_match_node(cpu_pmu_of_device_ids, pdev->dev.of_node);
if (node && of_id) {
init_fn = of_id->data;
ret = init_fn(pmu);
} else {
ret = probe_current_pmu(pmu);
}
if (ret) {
pr_notice("[perf] failed to probe PMU!\n");
goto out_free;
}
cpu_pmu = pmu;
cpu_pmu->plat_device = pdev;
cpu_pmu_init(cpu_pmu);
ret = nds32_pmu_register(cpu_pmu, PERF_TYPE_RAW);
if (!ret)
return 0;
out_free:
pr_notice("[perf] failed to register PMU devices!\n");
kfree(pmu);
return ret;
}
static struct platform_driver cpu_pmu_driver = {
.driver = {
.name = "nds32-pfm",
.of_match_table = cpu_pmu_of_device_ids,
},
.probe = cpu_pmu_device_probe,
.id_table = cpu_pmu_plat_device_ids,
};
static int __init register_pmu_driver(void)
{
int err = 0;
err = platform_driver_register(&cpu_pmu_driver);
if (err)
pr_notice("[perf] PMU initialization failed\n");
else
pr_notice("[perf] PMU initialization done\n");
return err;
}
device_initcall(register_pmu_driver);
/*
* References: arch/nds32/kernel/traps.c:__dump()
* You will need to know the NDS ABI first.
*/
static int unwind_frame_kernel(struct stackframe *frame)
{
int graph = 0;
#ifdef CONFIG_FRAME_POINTER
/* 0x3 means misalignment */
if (!kstack_end((void *)frame->fp) &&
!((unsigned long)frame->fp & 0x3) &&
((unsigned long)frame->fp >= TASK_SIZE)) {
/*
* The array index is based on the ABI, the below graph
* illustrate the reasons.
* Function call procedure: "smw" and "lmw" will always
* update SP and FP for you automatically.
*
* Stack Relative Address
* | | 0
* ----
* |LP| <-- SP(before smw) <-- FP(after smw) -1
* ----
* |FP| -2
* ----
* | | <-- SP(after smw) -3
*/
frame->lp = ((unsigned long *)frame->fp)[-1];
frame->fp = ((unsigned long *)frame->fp)[FP_OFFSET];
/* make sure CONFIG_FUNCTION_GRAPH_TRACER is turned on */
if (__kernel_text_address(frame->lp))
frame->lp = ftrace_graph_ret_addr
(NULL, &graph, frame->lp, NULL);
return 0;
} else {
return -EPERM;
}
#else
/*
* You can refer to arch/nds32/kernel/traps.c:__dump()
* Treat "sp" as "fp", but the "sp" is one frame ahead of "fp".
* And, the "sp" is not always correct.
*
* Stack Relative Address
* | | 0
* ----
* |LP| <-- SP(before smw) -1
* ----
* | | <-- SP(after smw) -2
* ----
*/
if (!kstack_end((void *)frame->sp)) {
frame->lp = ((unsigned long *)frame->sp)[1];
/* TODO: How to deal with the value in first
* "sp" is not correct?
*/
if (__kernel_text_address(frame->lp))
frame->lp = ftrace_graph_ret_addr
(tsk, &graph, frame->lp, NULL);
frame->sp = ((unsigned long *)frame->sp) + 1;
return 0;
} else {
return -EPERM;
}
#endif
}
static void notrace
walk_stackframe(struct stackframe *frame,
int (*fn_record)(struct stackframe *, void *),
void *data)
{
while (1) {
int ret;
if (fn_record(frame, data))
break;
ret = unwind_frame_kernel(frame);
if (ret < 0)
break;
}
}
/*
* Gets called by walk_stackframe() for every stackframe. This will be called
* whist unwinding the stackframe and is like a subroutine return so we use
* the PC.
*/
static int callchain_trace(struct stackframe *fr, void *data)
{
struct perf_callchain_entry_ctx *entry = data;
perf_callchain_store(entry, fr->lp);
return 0;
}
/*
* Get the return address for a single stackframe and return a pointer to the
* next frame tail.
*/
static unsigned long
user_backtrace(struct perf_callchain_entry_ctx *entry, unsigned long fp)
{
struct frame_tail buftail;
unsigned long lp = 0;
unsigned long *user_frame_tail =
(unsigned long *)(fp - (unsigned long)sizeof(buftail));
/* Check accessibility of one struct frame_tail beyond */
if (!access_ok(user_frame_tail, sizeof(buftail)))
return 0;
if (__copy_from_user_inatomic
(&buftail, user_frame_tail, sizeof(buftail)))
return 0;
/*
* Refer to unwind_frame_kernel() for more illurstration
*/
lp = buftail.stack_lp; /* ((unsigned long *)fp)[-1] */
fp = buftail.stack_fp; /* ((unsigned long *)fp)[FP_OFFSET] */
perf_callchain_store(entry, lp);
return fp;
}
static unsigned long
user_backtrace_opt_size(struct perf_callchain_entry_ctx *entry,
unsigned long fp)
{
struct frame_tail_opt_size buftail;
unsigned long lp = 0;
unsigned long *user_frame_tail =
(unsigned long *)(fp - (unsigned long)sizeof(buftail));
/* Check accessibility of one struct frame_tail beyond */
if (!access_ok(user_frame_tail, sizeof(buftail)))
return 0;
if (__copy_from_user_inatomic
(&buftail, user_frame_tail, sizeof(buftail)))
return 0;
/*
* Refer to unwind_frame_kernel() for more illurstration
*/
lp = buftail.stack_lp; /* ((unsigned long *)fp)[-1] */
fp = buftail.stack_fp; /* ((unsigned long *)fp)[FP_OFFSET] */
perf_callchain_store(entry, lp);
return fp;
}
/*
* This will be called when the target is in user mode
* This function will only be called when we use
* "PERF_SAMPLE_CALLCHAIN" in
* kernel/events/core.c:perf_prepare_sample()
*
* How to trigger perf_callchain_[user/kernel] :
* $ perf record -e cpu-clock --call-graph fp ./program
* $ perf report --call-graph
*/
unsigned long leaf_fp;
void
perf_callchain_user(struct perf_callchain_entry_ctx *entry,
struct pt_regs *regs)
{
unsigned long fp = 0;
unsigned long gp = 0;
unsigned long lp = 0;
unsigned long sp = 0;
unsigned long *user_frame_tail;
leaf_fp = 0;
perf_callchain_store(entry, regs->ipc);
fp = regs->fp;
gp = regs->gp;
lp = regs->lp;
sp = regs->sp;
if (entry->nr < PERF_MAX_STACK_DEPTH &&
(unsigned long)fp && !((unsigned long)fp & 0x7) && fp > sp) {
user_frame_tail =
(unsigned long *)(fp - (unsigned long)sizeof(fp));
if (!access_ok(user_frame_tail, sizeof(fp)))
return;
if (__copy_from_user_inatomic
(&leaf_fp, user_frame_tail, sizeof(fp)))
return;
if (leaf_fp == lp) {
/*
* Maybe this is non leaf function
* with optimize for size,
* or maybe this is the function
* with optimize for size
*/
struct frame_tail buftail;
user_frame_tail =
(unsigned long *)(fp -
(unsigned long)sizeof(buftail));
if (!access_ok(user_frame_tail, sizeof(buftail)))
return;
if (__copy_from_user_inatomic
(&buftail, user_frame_tail, sizeof(buftail)))
return;
if (buftail.stack_fp == gp) {
/* non leaf function with optimize
* for size condition
*/
struct frame_tail_opt_size buftail_opt_size;
user_frame_tail =
(unsigned long *)(fp - (unsigned long)
sizeof(buftail_opt_size));
if (!access_ok(user_frame_tail,
sizeof(buftail_opt_size)))
return;
if (__copy_from_user_inatomic
(&buftail_opt_size, user_frame_tail,
sizeof(buftail_opt_size)))
return;
perf_callchain_store(entry, lp);
fp = buftail_opt_size.stack_fp;
while ((entry->nr < PERF_MAX_STACK_DEPTH) &&
(unsigned long)fp &&
!((unsigned long)fp & 0x7) &&
fp > sp) {
sp = fp;
fp = user_backtrace_opt_size(entry, fp);
}
} else {
/* this is the function
* without optimize for size
*/
fp = buftail.stack_fp;
perf_callchain_store(entry, lp);
while ((entry->nr < PERF_MAX_STACK_DEPTH) &&
(unsigned long)fp &&
!((unsigned long)fp & 0x7) &&
fp > sp) {
sp = fp;
fp = user_backtrace(entry, fp);
}
}
} else {
/* this is leaf function */
fp = leaf_fp;
perf_callchain_store(entry, lp);
/* previous function callcahin */
while ((entry->nr < PERF_MAX_STACK_DEPTH) &&
(unsigned long)fp &&
!((unsigned long)fp & 0x7) && fp > sp) {
sp = fp;
fp = user_backtrace(entry, fp);
}
}
return;
}
}
/* This will be called when the target is in kernel mode */
void
perf_callchain_kernel(struct perf_callchain_entry_ctx *entry,
struct pt_regs *regs)
{
struct stackframe fr;
fr.fp = regs->fp;
fr.lp = regs->lp;
fr.sp = regs->sp;
walk_stackframe(&fr, callchain_trace, entry);
}
unsigned long perf_instruction_pointer(struct pt_regs *regs)
{
return instruction_pointer(regs);
}
unsigned long perf_misc_flags(struct pt_regs *regs)
{
int misc = 0;
if (user_mode(regs))
misc |= PERF_RECORD_MISC_USER;
else
misc |= PERF_RECORD_MISC_KERNEL;
return misc;
}