csky: Add pmu interrupt support

This patch add interrupt request and handler for csky pmu.
perf can record on hardware event with this patch applied.

Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
This commit is contained in:
Mao Han 2019-06-04 18:54:46 +08:00 committed by Guo Ren
parent ccffa1ad15
commit f622fbf205

View File

@ -11,17 +11,42 @@
#define CSKY_PMU_MAX_EVENTS 32
#define DEFAULT_COUNT_WIDTH 48
#define HPCR "<0, 0x0>" /* PMU Control reg */
#define HPCNTENR "<0, 0x4>" /* Count Enable reg */
#define HPCR "<0, 0x0>" /* PMU Control reg */
#define HPSPR "<0, 0x1>" /* Start PC reg */
#define HPEPR "<0, 0x2>" /* End PC reg */
#define HPSIR "<0, 0x3>" /* Soft Counter reg */
#define HPCNTENR "<0, 0x4>" /* Count Enable reg */
#define HPINTENR "<0, 0x5>" /* Interrupt Enable reg */
#define HPOFSR "<0, 0x6>" /* Interrupt Status reg */
/* The events for a given PMU register set. */
struct pmu_hw_events {
/*
* The events that are active on the PMU for the given index.
*/
struct perf_event *events[CSKY_PMU_MAX_EVENTS];
/*
* A 1 bit for an index indicates that the counter is being used for
* an event. A 0 means that the counter can be used.
*/
unsigned long used_mask[BITS_TO_LONGS(CSKY_PMU_MAX_EVENTS)];
};
static uint64_t (*hw_raw_read_mapping[CSKY_PMU_MAX_EVENTS])(void);
static void (*hw_raw_write_mapping[CSKY_PMU_MAX_EVENTS])(uint64_t val);
struct csky_pmu_t {
struct pmu pmu;
uint32_t count_width;
uint32_t hpcr;
static struct csky_pmu_t {
struct pmu pmu;
struct pmu_hw_events __percpu *hw_events;
struct platform_device *plat_device;
uint32_t count_width;
uint32_t hpcr;
u64 max_period;
} csky_pmu;
static int csky_pmu_irq;
#define to_csky_pmu(p) (container_of(p, struct csky_pmu, pmu))
#define cprgr(reg) \
({ \
@ -802,6 +827,47 @@ static const int csky_pmu_cache_map[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
},
};
int csky_pmu_event_set_period(struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
s64 left = local64_read(&hwc->period_left);
s64 period = hwc->sample_period;
int ret = 0;
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)csky_pmu.max_period)
left = csky_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));
if (hw_raw_write_mapping[hwc->idx] != NULL)
hw_raw_write_mapping[hwc->idx]((u64)(-left) &
csky_pmu.max_period);
cpwcr(HPOFSR, ~BIT(hwc->idx) & cprcr(HPOFSR));
perf_event_update_userpage(event);
return ret;
}
static void csky_perf_event_update(struct perf_event *event,
struct hw_perf_event *hwc)
{
@ -823,6 +889,11 @@ static void csky_perf_event_update(struct perf_event *event,
local64_sub(delta, &hwc->period_left);
}
static void csky_pmu_reset(void *info)
{
cpwcr(HPCR, BIT(31) | BIT(30) | BIT(1));
}
static void csky_pmu_read(struct perf_event *event)
{
csky_perf_event_update(event, &event->hw);
@ -899,6 +970,7 @@ static void csky_pmu_disable(struct pmu *pmu)
static void csky_pmu_start(struct perf_event *event, int flags)
{
unsigned long flg;
struct hw_perf_event *hwc = &event->hw;
int idx = hwc->idx;
@ -910,16 +982,34 @@ static void csky_pmu_start(struct perf_event *event, int flags)
hwc->state = 0;
csky_pmu_event_set_period(event);
local_irq_save(flg);
cpwcr(HPINTENR, BIT(idx) | cprcr(HPINTENR));
cpwcr(HPCNTENR, BIT(idx) | cprcr(HPCNTENR));
local_irq_restore(flg);
}
static void csky_pmu_stop_event(struct perf_event *event)
{
unsigned long flg;
struct hw_perf_event *hwc = &event->hw;
int idx = hwc->idx;
local_irq_save(flg);
cpwcr(HPINTENR, ~BIT(idx) & cprcr(HPINTENR));
cpwcr(HPCNTENR, ~BIT(idx) & cprcr(HPCNTENR));
local_irq_restore(flg);
}
static void csky_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)) {
cpwcr(HPCNTENR, ~BIT(idx) & cprcr(HPCNTENR));
csky_pmu_stop_event(event);
event->hw.state |= PERF_HES_STOPPED;
}
@ -932,22 +1022,26 @@ static void csky_pmu_stop(struct perf_event *event, int flags)
static void csky_pmu_del(struct perf_event *event, int flags)
{
struct pmu_hw_events *hw_events = this_cpu_ptr(csky_pmu.hw_events);
struct hw_perf_event *hwc = &event->hw;
csky_pmu_stop(event, PERF_EF_UPDATE);
hw_events->events[hwc->idx] = NULL;
perf_event_update_userpage(event);
}
/* allocate hardware counter and optionally start counting */
static int csky_pmu_add(struct perf_event *event, int flags)
{
struct pmu_hw_events *hw_events = this_cpu_ptr(csky_pmu.hw_events);
struct hw_perf_event *hwc = &event->hw;
local64_set(&hwc->prev_count, 0);
if (hw_raw_write_mapping[hwc->idx] != NULL)
hw_raw_write_mapping[hwc->idx](0);
hw_events->events[hwc->idx] = event;
hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
if (flags & PERF_EF_START)
csky_pmu_start(event, PERF_EF_RELOAD);
@ -956,8 +1050,110 @@ static int csky_pmu_add(struct perf_event *event, int flags)
return 0;
}
static irqreturn_t csky_pmu_handle_irq(int irq_num, void *dev)
{
struct perf_sample_data data;
struct pmu_hw_events *cpuc = this_cpu_ptr(csky_pmu.hw_events);
struct pt_regs *regs;
int idx;
/*
* Did an overflow occur?
*/
if (!cprcr(HPOFSR))
return IRQ_NONE;
/*
* Handle the counter(s) overflow(s)
*/
regs = get_irq_regs();
csky_pmu_disable(&csky_pmu.pmu);
for (idx = 0; idx < CSKY_PMU_MAX_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 (!(cprcr(HPOFSR) & BIT(idx)))
continue;
hwc = &event->hw;
csky_perf_event_update(event, &event->hw);
perf_sample_data_init(&data, 0, hwc->last_period);
csky_pmu_event_set_period(event);
if (perf_event_overflow(event, &data, regs))
csky_pmu_stop_event(event);
}
csky_pmu_enable(&csky_pmu.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 int csky_pmu_request_irq(irq_handler_t handler)
{
int err, irqs;
struct platform_device *pmu_device = csky_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;
}
csky_pmu_irq = platform_get_irq(pmu_device, 0);
if (csky_pmu_irq < 0)
return -ENODEV;
err = request_percpu_irq(csky_pmu_irq, handler, "csky-pmu",
this_cpu_ptr(csky_pmu.hw_events));
if (err) {
pr_err("unable to request IRQ%d for CSKY PMU counters\n",
csky_pmu_irq);
return err;
}
return 0;
}
static void csky_pmu_free_irq(void)
{
int irq;
struct platform_device *pmu_device = csky_pmu.plat_device;
irq = platform_get_irq(pmu_device, 0);
if (irq >= 0)
free_percpu_irq(irq, this_cpu_ptr(csky_pmu.hw_events));
}
int init_hw_perf_events(void)
{
csky_pmu.hw_events = alloc_percpu_gfp(struct pmu_hw_events,
GFP_KERNEL);
if (!csky_pmu.hw_events) {
pr_info("failed to allocate per-cpu PMU data.\n");
return -ENOMEM;
}
csky_pmu.pmu = (struct pmu) {
.pmu_enable = csky_pmu_enable,
.pmu_disable = csky_pmu_disable,
@ -1029,11 +1225,19 @@ int init_hw_perf_events(void)
hw_raw_write_mapping[0x1a] = csky_pmu_write_l2wac;
hw_raw_write_mapping[0x1b] = csky_pmu_write_l2wmc;
csky_pmu.pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
return 0;
}
cpwcr(HPCR, BIT(31) | BIT(30) | BIT(1));
static int csky_pmu_starting_cpu(unsigned int cpu)
{
enable_percpu_irq(csky_pmu_irq, 0);
return 0;
}
return perf_pmu_register(&csky_pmu.pmu, "cpu", PERF_TYPE_RAW);
static int csky_pmu_dying_cpu(unsigned int cpu)
{
disable_percpu_irq(csky_pmu_irq);
return 0;
}
int csky_pmu_device_probe(struct platform_device *pdev,
@ -1052,6 +1256,33 @@ int csky_pmu_device_probe(struct platform_device *pdev,
&csky_pmu.count_width)) {
csky_pmu.count_width = DEFAULT_COUNT_WIDTH;
}
csky_pmu.max_period = BIT(csky_pmu.count_width) - 1;
csky_pmu.plat_device = pdev;
/* Ensure the PMU has sane values out of reset. */
on_each_cpu(csky_pmu_reset, &csky_pmu, 1);
ret = csky_pmu_request_irq(csky_pmu_handle_irq);
if (ret) {
csky_pmu.pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
pr_notice("[perf] PMU request irq fail!\n");
}
ret = cpuhp_setup_state(CPUHP_AP_PERF_ONLINE, "AP_PERF_ONLINE",
csky_pmu_starting_cpu,
csky_pmu_dying_cpu);
if (ret) {
csky_pmu_free_irq();
free_percpu(csky_pmu.hw_events);
return ret;
}
ret = perf_pmu_register(&csky_pmu.pmu, "cpu", PERF_TYPE_RAW);
if (ret) {
csky_pmu_free_irq();
free_percpu(csky_pmu.hw_events);
}
return ret;
}