diff options
| -rw-r--r-- | drivers/perf/marvell_cn10k_ddr_pmu.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/drivers/perf/marvell_cn10k_ddr_pmu.c b/drivers/perf/marvell_cn10k_ddr_pmu.c index d93268943e23..19c8744e1a23 100644 --- a/drivers/perf/marvell_cn10k_ddr_pmu.c +++ b/drivers/perf/marvell_cn10k_ddr_pmu.c @@ -11,6 +11,7 @@ #include <linux/of_address.h> #include <linux/of_device.h> #include <linux/perf_event.h> +#include <linux/hrtimer.h> /* Performance Counters Operating Mode Control Registers */ #define DDRC_PERF_CNT_OP_MODE_CTRL 0x8020 @@ -127,6 +128,7 @@ struct cn10k_ddr_pmu { struct device *dev; int active_events; struct perf_event *events[DDRC_PERF_NUM_COUNTERS]; + struct hrtimer hrtimer; }; #define to_cn10k_ddr_pmu(p) container_of(p, struct cn10k_ddr_pmu, pmu) @@ -251,6 +253,18 @@ static const struct attribute_group *cn10k_attr_groups[] = { NULL, }; +/* Default poll timeout is 100 sec, which is very sufficient for + * 48 bit counter incremented max at 5.6 GT/s, which may take many + * hours to overflow. + */ +static unsigned long cn10k_ddr_pmu_poll_period_sec = 100; +module_param_named(poll_period_sec, cn10k_ddr_pmu_poll_period_sec, ulong, 0644); + +static ktime_t cn10k_ddr_pmu_timer_period(void) +{ + return ms_to_ktime((u64)cn10k_ddr_pmu_poll_period_sec * USEC_PER_SEC); +} + static int ddr_perf_get_event_bitmap(int eventid, u64 *event_bitmap) { switch (eventid) { @@ -433,6 +447,10 @@ static int cn10k_ddr_perf_event_add(struct perf_event *event, int flags) pmu->active_events++; hwc->idx = counter; + if (pmu->active_events == 1) + hrtimer_start(&pmu->hrtimer, cn10k_ddr_pmu_timer_period(), + HRTIMER_MODE_REL_PINNED); + if (counter < DDRC_PERF_NUM_GEN_COUNTERS) { /* Generic counters, configure event id */ reg_offset = DDRC_PERF_CFG(counter); @@ -484,6 +502,10 @@ static void cn10k_ddr_perf_event_del(struct perf_event *event, int flags) cn10k_ddr_perf_free_counter(pmu, counter); pmu->active_events--; hwc->idx = -1; + + /* Cancel timer when no events to capture */ + if (pmu->active_events == 0) + hrtimer_cancel(&pmu->hrtimer); } static void cn10k_ddr_perf_pmu_enable(struct pmu *pmu) @@ -502,6 +524,92 @@ static void cn10k_ddr_perf_pmu_disable(struct pmu *pmu) DDRC_PERF_CNT_END_OP_CTRL); } +static void cn10k_ddr_perf_event_update_all(struct cn10k_ddr_pmu *pmu) +{ + struct hw_perf_event *hwc; + int i; + + for (i = 0; i < DDRC_PERF_NUM_GEN_COUNTERS; i++) { + if (pmu->events[i] == NULL) + continue; + + cn10k_ddr_perf_event_update(pmu->events[i]); + } + + /* Reset previous count as h/w counter are reset */ + for (i = 0; i < DDRC_PERF_NUM_GEN_COUNTERS; i++) { + if (pmu->events[i] == NULL) + continue; + + hwc = &pmu->events[i]->hw; + local64_set(&hwc->prev_count, 0); + } +} + +static irqreturn_t cn10k_ddr_pmu_overflow_handler(struct cn10k_ddr_pmu *pmu) +{ + struct perf_event *event; + struct hw_perf_event *hwc; + u64 prev_count, new_count; + u64 value; + int i; + + event = pmu->events[DDRC_PERF_READ_COUNTER_IDX]; + if (event) { + hwc = &event->hw; + prev_count = local64_read(&hwc->prev_count); + new_count = cn10k_ddr_perf_read_counter(pmu, hwc->idx); + + /* Overflow condition is when new count less than + * previous count + */ + if (new_count < prev_count) + cn10k_ddr_perf_event_update(event); + } + + event = pmu->events[DDRC_PERF_WRITE_COUNTER_IDX]; + if (event) { + hwc = &event->hw; + prev_count = local64_read(&hwc->prev_count); + new_count = cn10k_ddr_perf_read_counter(pmu, hwc->idx); + + /* Overflow condition is when new count less than + * previous count + */ + if (new_count < prev_count) + cn10k_ddr_perf_event_update(event); + } + + for (i = 0; i < DDRC_PERF_NUM_GEN_COUNTERS; i++) { + if (pmu->events[i] == NULL) + continue; + + value = cn10k_ddr_perf_read_counter(pmu, i); + if (value == DDRC_PERF_CNT_MAX_VALUE) { + pr_info("Counter-(%d) reached max value\n", i); + cn10k_ddr_perf_event_update_all(pmu); + cn10k_ddr_perf_pmu_disable(&pmu->pmu); + cn10k_ddr_perf_pmu_enable(&pmu->pmu); + } + } + + return IRQ_HANDLED; +} + +static enum hrtimer_restart cn10k_ddr_pmu_timer_handler(struct hrtimer *hrtimer) +{ + struct cn10k_ddr_pmu *pmu = container_of(hrtimer, struct cn10k_ddr_pmu, + hrtimer); + unsigned long flags; + + local_irq_save(flags); + cn10k_ddr_pmu_overflow_handler(pmu); + local_irq_restore(flags); + + hrtimer_forward_now(hrtimer, cn10k_ddr_pmu_timer_period()); + return HRTIMER_RESTART; +} + static int cn10k_ddr_perf_probe(struct platform_device *pdev) { struct cn10k_ddr_pmu *ddr_pmu; @@ -550,6 +658,9 @@ static int cn10k_ddr_perf_probe(struct platform_device *pdev) if (!name) return -ENOMEM; + hrtimer_init(&ddr_pmu->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + ddr_pmu->hrtimer.function = cn10k_ddr_pmu_timer_handler; + ret = perf_pmu_register(&ddr_pmu->pmu, name, -1); if (ret) return ret; |