Messages in this thread Patch in this message | | | From | Tuan Phan <> | Subject | [PATCH v2] driver/perf: Add PMU driver for the ARM DMC-620 memory controller. | Date | Mon, 11 May 2020 13:44:52 -0700 |
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DMC-620 PMU supports 10 total counters that are independently programmable for different events and can be individually started and stopped.
ACPI is only supported; device tree support is welcomed to be added and tested for other platforms.
Usage example: #perf stat -e arm_dmc620_10008c000/clk_cycle_count/ -C 0 Get perf event for clk_cycle_count counter.
#perf stat -e arm_dmc620_10008c000/clkdiv2_allocate,mask=0x1f,match=0x2f, incr=2,invert=1/ -C 0 The above example shows how to specify mask, match, incr, invert parameters for clkdiv2_allocate event.
Signed-off-by: Tuan Phan <tuanphan@os.amperecomputing.com> --- Changes in v2: - Removed IRQF_SHARED flag and added support for multiple PMUs sharing the same interrupt. - Fixed an interrupt handler race condition.
The ACPI binding spec for PMU DMC620 is under beta and located in ARM server group under project "ACPI on ARM".
drivers/perf/Kconfig | 8 + drivers/perf/Makefile | 1 + drivers/perf/arm_dmc620_pmu.c | 869 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 878 insertions(+) create mode 100644 drivers/perf/arm_dmc620_pmu.c
diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig index 09ae8a9..2724a55 100644 --- a/drivers/perf/Kconfig +++ b/drivers/perf/Kconfig @@ -129,4 +129,12 @@ config ARM_SPE_PMU Extension, which provides periodic sampling of operations in the CPU pipeline and reports this via the perf AUX interface. +config ARM_DMC620_PMU + tristate "Enable PMU support for the Arm DMC-620 memory controller" + depends on ARM64 && ACPI + default n + help + Support for PMU events monitoring on the Arm DMC-620 memory + controller. + endmenu diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile index 2ebb4de..5d577d1 100644 --- a/drivers/perf/Makefile +++ b/drivers/perf/Makefile @@ -12,3 +12,4 @@ obj-$(CONFIG_QCOM_L3_PMU) += qcom_l3_pmu.o obj-$(CONFIG_THUNDERX2_PMU) += thunderx2_pmu.o obj-$(CONFIG_XGENE_PMU) += xgene_pmu.o obj-$(CONFIG_ARM_SPE_PMU) += arm_spe_pmu.o +obj-$(CONFIG_ARM_DMC620_PMU) += arm_dmc620_pmu.o diff --git a/drivers/perf/arm_dmc620_pmu.c b/drivers/perf/arm_dmc620_pmu.c new file mode 100644 index 0000000..5a80cddf --- /dev/null +++ b/drivers/perf/arm_dmc620_pmu.c @@ -0,0 +1,869 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Arm DMC-620 memory controller PMU driver. + * + * Copyright (C) 2020 Ampere Computing LLC. + */ + +#define DMC620_PMUNAME "arm_dmc620" +#define DMC620_DRVNAME DMC620_PMUNAME "_pmu" +#define pr_fmt(fmt) DMC620_DRVNAME ": " fmt + +#include <linux/acpi.h> +#include <linux/bitops.h> +#include <linux/cpuhotplug.h> +#include <linux/cpumask.h> +#include <linux/device.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/perf_event.h> +#include <linux/perf/arm_pmu.h> +#include <linux/platform_device.h> +#include <linux/printk.h> +#include <linux/rculist.h> +#include <linux/refcount.h> + +#define DMC620_PA_SHIFT 12 +#define DMC620_CNT_MAX_PERIOD 0xffffffff +#define DMC620_PMU_CLKDIV2_MAX_COUNTERS 8 +#define DMC620_PMU_CLK_MAX_COUNTERS 2 +#define DMC620_PMU_MAX_COUNTERS \ + (DMC620_PMU_CLKDIV2_MAX_COUNTERS + DMC620_PMU_CLK_MAX_COUNTERS) + +#define DMC620_PMU_OVERFLOW_STATUS_CLKDIV2_OFFSET 8 +#define DMC620_PMU_OVERFLOW_STATUS_CLKDIV2_MASK \ + (DMC620_PMU_CLKDIV2_MAX_COUNTERS - 1) +#define DMC620_PMU_OVERFLOW_STATUS_CLK_OFFSET 12 +#define DMC620_PMU_OVERFLOW_STATUS_CLK_MASK \ + (DMC620_PMU_CLK_MAX_COUNTERS - 1) +#define DMC620_PMU_COUNTERS_BASE_OFFSET 16 +#define DMC620_PMU_COUNTER_MASK_31_00_OFFSET 0 +#define DMC620_PMU_COUNTER_MASK_63_32_OFFSET 4 +#define DMC620_PMU_COUNTER_MATCH_31_00_OFFSET 8 +#define DMC620_PMU_COUNTER_MATCH_63_32_OFFSET 12 +#define DMC620_PMU_COUNTER_CONTROL_OFFSET 16 +#define DMC620_PMU_COUNTER_CONTROL_ENABLE_MASK BIT(0) +#define DMC620_PMU_COUNTER_CONTROL_INVERT_SHIFT 1 +#define DMC620_PMU_COUNTER_CONTROL_EVENT_MUX (((x)&0x1f)>>2) +#define DMC620_PMU_COUNTER_CONTROL_EVENT_MUX_SHIFT 2 +#define DMC620_PMU_COUNTER_CONTROL_INCR (((x)&0x1ff)>>7) +#define DMC620_PMU_COUNTER_CONTROL_INCR_SHIFT 7 +#define DMC620_PMU_COUNTER_SNAPSHOT_OFFSET 24 +#define DMC620_PMU_COUNTER_VALUE_OFFSET 32 +#define DMC620_PMU_COUNTER_REG_BYTE_LENGTH 40 + +#define DMC620_PMU_CLKDIV2_CYCLE_COUNT 0x0 +#define DMC620_PMU_CLKDIV2_ALLOCATE 0x1 +#define DMC620_PMU_CLKDIV2_QUEUE_DEPTH 0x2 +#define DMC620_PMU_CLKDIV2_WAITING_FOR_WR_DATA 0x3 +#define DMC620_PMU_CLKDIV2_READ_BACKLOG 0x4 +#define DMC620_PMU_CLKDIV2_WAITING_FOR_MI 0x5 +#define DMC620_PMU_CLKDIV2_HAZARD_RESOLUTION 0x6 +#define DMC620_PMU_CLKDIV2_ENQUEUE 0x7 +#define DMC620_PMU_CLKDIV2_ARBITRATE 0x8 +#define DMC620_PMU_CLKDIV2_LRANK_TURNAROUND_ACTIVATE 0x9 +#define DMC620_PMU_CLKDIV2_PRANK_TURNAROUND_ACTIVATE 0xA +#define DMC620_PMU_CLKDIV2_READ_DEPTH 0xB +#define DMC620_PMU_CLKDIV2_WRITE_DEPTH 0xC +#define DMC620_PMU_CLKDIV2_HIGHHIGH_QOS_DEPTH 0xD +#define DMC620_PMU_CLKDIV2_HIGH_QOS_DEPTH 0xE +#define DMC620_PMU_CLKDIV2_MEDIUM_QOS_DEPTH 0xF +#define DMC620_PMU_CLKDIV2_LOW_QOS_DEPTH 0x10 +#define DMC620_PMU_CLKDIV2_ACTIVATE 0x11 +#define DMC620_PMU_CLKDIV2_RDWR 0x12 +#define DMC620_PMU_CLKDIV2_REFRESH 0x13 +#define DMC620_PMU_CLKDIV2_TRAINING_REQUEST 0x14 +#define DMC620_PMU_CLKDIV2_T_MAC_TRACKER 0x15 +#define DMC620_PMU_CLKDIV2_BK_FSM_TRACKER 0x16 +#define DMC620_PMU_CLKDIV2_BK_OPEN_TRACKER 0x17 +#define DMC620_PMU_CLKDIV2_RANKS_IN_PWR_DOWN 0x18 +#define DMC620_PMU_CLKDIV2_RANKS_IN_SREF 0x19 +#define DMC620_PMU_CLK_CYCLE_COUNTER 0x20 +#define DMC620_PMU_CLK_REQUEST 0x21 +#define DMC620_PMU_CLK_UPLOAD_STALL 0x22 +#define DMC620_PMU_CLK_INDICATE_MASK 0x20 + +static LIST_HEAD(dmc620_pmu_affinities); +static DEFINE_MUTEX(dmc620_pmu_affinity_lock); + +struct dmc620_pmu_affinity { + struct hlist_node node; + struct list_head affinity_list; + struct list_head instance_list; + refcount_t refcount; + unsigned int irq; + unsigned int cpu; +}; + +struct dmc620_pmu { + struct pmu pmu; + struct platform_device *pdev; + + void __iomem *base; + struct dmc620_pmu_affinity *affinity; + struct list_head affinity_list; + + /* + * We put all clkdiv2 and clk counters to a same array. + * The first DMC620_PMU_CLKDIV2_MAX_COUNTERS bits belong to + * clkdiv2 counters, the last DMC620_PMU_CLK_MAX_COUNTERS + * belong to clk counters. + */ + DECLARE_BITMAP(used_mask, DMC620_PMU_MAX_COUNTERS); + struct perf_event *act_counter[DMC620_PMU_MAX_COUNTERS]; +}; + +#define to_dmc620_pmu(p) (container_of(p, struct dmc620_pmu, pmu)) + +static int cpuhp_state_num; + +static ssize_t +dmc620_pmu_events_sysfs_show(struct device *dev, + struct device_attribute *attr, char *page) +{ + struct perf_pmu_events_attr *pmu_attr; + + pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr); + + return sprintf(page, "event=0x%03llx\n", pmu_attr->id); +} + +#define DMC620_PMU_EVENT_ATTR(name, config) \ + PMU_EVENT_ATTR(name, dmc620_pmu_event_attr_##name, \ + config, dmc620_pmu_events_sysfs_show) + +/* clkdiv2 events list */ +DMC620_PMU_EVENT_ATTR(clkdiv2_cycle_count, + DMC620_PMU_CLKDIV2_CYCLE_COUNT); +DMC620_PMU_EVENT_ATTR(clkdiv2_allocate, + DMC620_PMU_CLKDIV2_ALLOCATE); +DMC620_PMU_EVENT_ATTR(clkdiv2_queue_depth, + DMC620_PMU_CLKDIV2_QUEUE_DEPTH); +DMC620_PMU_EVENT_ATTR(clkdiv2_waiting_for_wr_data, + DMC620_PMU_CLKDIV2_WAITING_FOR_WR_DATA); +DMC620_PMU_EVENT_ATTR(clkdiv2_read_backlog, + DMC620_PMU_CLKDIV2_READ_BACKLOG); +DMC620_PMU_EVENT_ATTR(clkdiv2_waiting_for_mi, + DMC620_PMU_CLKDIV2_WAITING_FOR_MI); +DMC620_PMU_EVENT_ATTR(clkdiv2_hazard_resolution, + DMC620_PMU_CLKDIV2_HAZARD_RESOLUTION); +DMC620_PMU_EVENT_ATTR(clkdiv2_enqueue, + DMC620_PMU_CLKDIV2_ENQUEUE); +DMC620_PMU_EVENT_ATTR(clkdiv2_arbitrate, + DMC620_PMU_CLKDIV2_ARBITRATE); +DMC620_PMU_EVENT_ATTR(clkdiv2_lrank_turnaround_activate, + DMC620_PMU_CLKDIV2_LRANK_TURNAROUND_ACTIVATE); +DMC620_PMU_EVENT_ATTR(clkdiv2_prank_turnaround_activate, + DMC620_PMU_CLKDIV2_PRANK_TURNAROUND_ACTIVATE); +DMC620_PMU_EVENT_ATTR(clkdiv2_read_depth, + DMC620_PMU_CLKDIV2_READ_DEPTH); +DMC620_PMU_EVENT_ATTR(clkdiv2_write_depth, + DMC620_PMU_CLKDIV2_WRITE_DEPTH); +DMC620_PMU_EVENT_ATTR(clkdiv2_highigh_qos_depth, + DMC620_PMU_CLKDIV2_HIGHHIGH_QOS_DEPTH); +DMC620_PMU_EVENT_ATTR(clkdiv2_high_qos_depth, + DMC620_PMU_CLKDIV2_HIGH_QOS_DEPTH); +DMC620_PMU_EVENT_ATTR(clkdiv2_medium_qos_depth, + DMC620_PMU_CLKDIV2_MEDIUM_QOS_DEPTH); +DMC620_PMU_EVENT_ATTR(clkdiv2_low_qos_depth, + DMC620_PMU_CLKDIV2_LOW_QOS_DEPTH); +DMC620_PMU_EVENT_ATTR(clkdiv2_activate, + DMC620_PMU_CLKDIV2_ACTIVATE); +DMC620_PMU_EVENT_ATTR(clkdiv2_rdwr, + DMC620_PMU_CLKDIV2_RDWR); +DMC620_PMU_EVENT_ATTR(clkdiv2_refresh, + DMC620_PMU_CLKDIV2_REFRESH); +DMC620_PMU_EVENT_ATTR(clkdiv2_training_request, + DMC620_PMU_CLKDIV2_TRAINING_REQUEST); +DMC620_PMU_EVENT_ATTR(clkdiv2_t_mac_tracker, + DMC620_PMU_CLKDIV2_T_MAC_TRACKER); +DMC620_PMU_EVENT_ATTR(clkdiv2_bk_fsm_tracker, + DMC620_PMU_CLKDIV2_BK_FSM_TRACKER); +DMC620_PMU_EVENT_ATTR(clkdiv2_bk_open_tracker, + DMC620_PMU_CLKDIV2_BK_OPEN_TRACKER); +DMC620_PMU_EVENT_ATTR(clkdiv2_ranks_in_pwr_down, + DMC620_PMU_CLKDIV2_RANKS_IN_PWR_DOWN); +DMC620_PMU_EVENT_ATTR(clkdiv2_ranks_in_sref, + DMC620_PMU_CLKDIV2_RANKS_IN_SREF); + +/* clk events list */ +DMC620_PMU_EVENT_ATTR(clk_cycle_count, + DMC620_PMU_CLK_CYCLE_COUNTER); +DMC620_PMU_EVENT_ATTR(clk_request, + DMC620_PMU_CLK_REQUEST); +DMC620_PMU_EVENT_ATTR(clk_upload_stall, + DMC620_PMU_CLK_UPLOAD_STALL); + +static struct attribute *dmc620_pmu_events_attrs[] = { + &dmc620_pmu_event_attr_clkdiv2_cycle_count.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_allocate.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_queue_depth.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_waiting_for_wr_data.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_read_backlog.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_waiting_for_mi.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_hazard_resolution.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_enqueue.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_arbitrate.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_lrank_turnaround_activate.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_prank_turnaround_activate.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_read_depth.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_write_depth.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_highigh_qos_depth.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_high_qos_depth.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_medium_qos_depth.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_low_qos_depth.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_activate.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_rdwr.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_refresh.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_training_request.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_t_mac_tracker.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_bk_fsm_tracker.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_bk_open_tracker.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_ranks_in_pwr_down.attr.attr, + &dmc620_pmu_event_attr_clkdiv2_ranks_in_sref.attr.attr, + &dmc620_pmu_event_attr_clk_cycle_count.attr.attr, + &dmc620_pmu_event_attr_clk_request.attr.attr, + &dmc620_pmu_event_attr_clk_upload_stall.attr.attr, + NULL, +}; + +static struct attribute_group dmc620_pmu_events_attr_group = { + .name = "events", + .attrs = dmc620_pmu_events_attrs, +}; + +/* User ABI */ +#define ATTR_CFG_FLD_mask_CFG config +#define ATTR_CFG_FLD_mask_LO 0 +#define ATTR_CFG_FLD_mask_HI 44 +#define ATTR_CFG_FLD_match_CFG config1 +#define ATTR_CFG_FLD_match_LO 0 +#define ATTR_CFG_FLD_match_HI 44 +#define ATTR_CFG_FLD_invert_CFG config2 +#define ATTR_CFG_FLD_invert_LO 0 +#define ATTR_CFG_FLD_invert_HI 0 +#define ATTR_CFG_FLD_incr_CFG config2 +#define ATTR_CFG_FLD_incr_LO 1 +#define ATTR_CFG_FLD_incr_HI 2 +#define ATTR_CFG_FLD_event_CFG config2 +#define ATTR_CFG_FLD_event_LO 3 +#define ATTR_CFG_FLD_event_HI 8 + +#define __GEN_PMU_FORMAT_ATTR(cfg, lo, hi) \ + (lo) == (hi) ? #cfg ":" #lo "\n" : #cfg ":" #lo "-" #hi + +#define _GEN_PMU_FORMAT_ATTR(cfg, lo, hi) \ + __GEN_PMU_FORMAT_ATTR(cfg, lo, hi) + +#define GEN_PMU_FORMAT_ATTR(name) \ + PMU_FORMAT_ATTR(name, \ + _GEN_PMU_FORMAT_ATTR(ATTR_CFG_FLD_##name##_CFG, \ + ATTR_CFG_FLD_##name##_LO, \ + ATTR_CFG_FLD_##name##_HI)) + +#define _ATTR_CFG_GET_FLD(attr, cfg, lo, hi) \ + ((((attr)->cfg) >> lo) & GENMASK(hi - lo, 0)) + +#define ATTR_CFG_GET_FLD(attr, name) \ + _ATTR_CFG_GET_FLD(attr, \ + ATTR_CFG_FLD_##name##_CFG, \ + ATTR_CFG_FLD_##name##_LO, \ + ATTR_CFG_FLD_##name##_HI) + +GEN_PMU_FORMAT_ATTR(mask); +GEN_PMU_FORMAT_ATTR(match); +GEN_PMU_FORMAT_ATTR(invert); +GEN_PMU_FORMAT_ATTR(incr); +GEN_PMU_FORMAT_ATTR(event); + +static struct attribute *dmc620_pmu_formats_attrs[] = { + &format_attr_mask.attr, + &format_attr_match.attr, + &format_attr_invert.attr, + &format_attr_incr.attr, + &format_attr_event.attr, + NULL, +}; + +static struct attribute_group dmc620_pmu_format_attr_group = { + .name = "format", + .attrs = dmc620_pmu_formats_attrs, +}; + +static const struct attribute_group *dmc620_pmu_attr_groups[] = { + &dmc620_pmu_events_attr_group, + &dmc620_pmu_format_attr_group, + NULL, +}; + +static inline +unsigned int dmc620_pmu_creg_read(struct dmc620_pmu *dmc620_pmu, + unsigned int idx, + unsigned int offset) +{ + return readl(dmc620_pmu->base + DMC620_PMU_COUNTERS_BASE_OFFSET + + (idx * DMC620_PMU_COUNTER_REG_BYTE_LENGTH + offset)); +} + +static inline +void dmc620_pmu_creg_write(struct dmc620_pmu *dmc620_pmu, + unsigned int idx, + unsigned int offset, + unsigned int val) +{ + writel(val, dmc620_pmu->base + DMC620_PMU_COUNTERS_BASE_OFFSET + + (idx * DMC620_PMU_COUNTER_REG_BYTE_LENGTH + offset)); +} + +static +unsigned int dmc620_event_to_counter_control(struct perf_event *event) +{ + struct perf_event_attr *attr = &event->attr; + unsigned int reg = 0; + + reg |= ATTR_CFG_GET_FLD(attr, invert) << + DMC620_PMU_COUNTER_CONTROL_INVERT_SHIFT; + reg |= ATTR_CFG_GET_FLD(attr, incr) << + DMC620_PMU_COUNTER_CONTROL_INCR_SHIFT; + reg |= (ATTR_CFG_GET_FLD(attr, event) & + ~DMC620_PMU_CLK_INDICATE_MASK) << + DMC620_PMU_COUNTER_CONTROL_EVENT_MUX_SHIFT; + + return reg; +} + +static int dmc620_get_event_idx(struct perf_event *event) +{ + struct dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu); + int idx, start_idx, end_idx; + + if (ATTR_CFG_GET_FLD(&event->attr, event) & + DMC620_PMU_CLK_INDICATE_MASK) { + start_idx = DMC620_PMU_CLKDIV2_MAX_COUNTERS; + end_idx = DMC620_PMU_MAX_COUNTERS; + } else { + start_idx = 0; + end_idx = DMC620_PMU_CLKDIV2_MAX_COUNTERS; + } + + for (idx = start_idx; idx < end_idx; ++idx) { + if (!test_and_set_bit(idx, dmc620_pmu->used_mask)) + return idx; + } + + /* The counters are all in use. */ + return -EAGAIN; +} + +static u64 dmc620_pmu_read_counter(struct perf_event *event) +{ + struct dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu); + + return (u64)dmc620_pmu_creg_read(dmc620_pmu, + event->hw.idx, + DMC620_PMU_COUNTER_VALUE_OFFSET); +} + +static void dmc620_pmu_event_update(struct perf_event *event) +{ + struct hw_perf_event *hwc = &event->hw; + u64 delta, prev_count, new_count; + + do { + /* We may also be called from the irq handler */ + prev_count = local64_read(&hwc->prev_count); + new_count = dmc620_pmu_read_counter(event); + } while (local64_cmpxchg(&hwc->prev_count, + prev_count, new_count) != prev_count); + delta = (new_count - prev_count) & DMC620_CNT_MAX_PERIOD; + local64_add(delta, &event->count); +} + +static void dmc620_pmu_event_set_period(struct perf_event *event) +{ + struct dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu); + + /* + * All DMC-620 PMU event counters are 32bit counters. + * To handle cases of extreme interrupt latency, we program + * the counter with half of the max count for the counters. + */ + u64 val = DMC620_CNT_MAX_PERIOD >> 1; + + local64_set(&event->hw.prev_count, val); + dmc620_pmu_creg_write(dmc620_pmu, + event->hw.idx, DMC620_PMU_COUNTER_VALUE_OFFSET, + val); +} + +static void dmc620_pmu_enable_counter(struct perf_event *event) +{ + struct dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu); + unsigned int reg; + + reg = dmc620_pmu_creg_read(dmc620_pmu, + event->hw.idx, DMC620_PMU_COUNTER_CONTROL_OFFSET); + reg |= DMC620_PMU_COUNTER_CONTROL_ENABLE_MASK; + dmc620_pmu_creg_write(dmc620_pmu, + event->hw.idx, DMC620_PMU_COUNTER_CONTROL_OFFSET, + reg); +} + +static void dmc620_pmu_disable_counter(struct perf_event *event) +{ + struct dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu); + unsigned int reg; + + reg = dmc620_pmu_creg_read(dmc620_pmu, + event->hw.idx, DMC620_PMU_COUNTER_CONTROL_OFFSET); + reg &= ~DMC620_PMU_COUNTER_CONTROL_ENABLE_MASK; + dmc620_pmu_creg_write(dmc620_pmu, + event->hw.idx, DMC620_PMU_COUNTER_CONTROL_OFFSET, + reg); +} + +static irqreturn_t dmc620_pmu_handle_irq(int irq_num, void *data) +{ + struct dmc620_pmu_affinity *aff = data; + struct dmc620_pmu *dmc620_pmu; + irqreturn_t ret = IRQ_NONE; + + rcu_read_lock(); + list_for_each_entry_rcu(dmc620_pmu, + &aff->instance_list, affinity_list) { + unsigned long status_clkdiv2, status_clk; + struct perf_event *event; + unsigned int idx; + + status_clkdiv2 = readl(dmc620_pmu->base + + DMC620_PMU_OVERFLOW_STATUS_CLKDIV2_OFFSET); + status_clk = readl(dmc620_pmu->base + + DMC620_PMU_OVERFLOW_STATUS_CLK_OFFSET); + if (!status_clkdiv2 && !status_clk) + continue; + + for (idx = 0; idx < DMC620_PMU_MAX_COUNTERS; idx++) { + event = dmc620_pmu->act_counter[idx]; + if (!event) + continue; + dmc620_pmu_disable_counter(event); + } + + for_each_set_bit(idx, &status_clkdiv2, + DMC620_PMU_CLKDIV2_MAX_COUNTERS) { + event = dmc620_pmu->act_counter[idx]; + if (WARN_ON_ONCE(!event)) + continue; + dmc620_pmu_event_update(event); + dmc620_pmu_event_set_period(event); + } + + for_each_set_bit(idx, &status_clk, + DMC620_PMU_CLK_MAX_COUNTERS) { + event = dmc620_pmu->act_counter[idx + + DMC620_PMU_CLKDIV2_MAX_COUNTERS]; + if (WARN_ON_ONCE(!event)) + continue; + dmc620_pmu_event_update(event); + dmc620_pmu_event_set_period(event); + } + + if (status_clkdiv2) + writel(0, dmc620_pmu->base + + DMC620_PMU_OVERFLOW_STATUS_CLKDIV2_OFFSET); + if (status_clk) + writel(0, dmc620_pmu->base + + DMC620_PMU_OVERFLOW_STATUS_CLK_OFFSET); + + for (idx = 0; idx < DMC620_PMU_MAX_COUNTERS; idx++) { + event = dmc620_pmu->act_counter[idx]; + if (!event) + continue; + if (!(event->hw.state & PERF_HES_STOPPED)) + dmc620_pmu_enable_counter(event); + } + ret = IRQ_HANDLED; + } + rcu_read_unlock(); + + return ret; +} + +static struct dmc620_pmu_affinity *__dmc620_pmu_get_affinity(int irq) +{ + struct dmc620_pmu_affinity *aff; + int ret; + + list_for_each_entry(aff, &dmc620_pmu_affinities, affinity_list) + if (aff->irq == irq && refcount_inc_not_zero(&aff->refcount)) + return aff; + + aff = kzalloc(sizeof(*aff), GFP_KERNEL); + if (!aff) + return ERR_PTR(-ENOMEM); + + aff->instance_list.next = &aff->instance_list; + aff->instance_list.prev = &aff->instance_list; + + /* Pick one CPU to be the preferred one to use */ + aff->cpu = raw_smp_processor_id(); + refcount_set(&aff->refcount, 1); + + ret = request_irq(irq, dmc620_pmu_handle_irq, + IRQF_NOBALANCING | IRQF_NO_THREAD, + "dmc620-pmu", aff); + if (ret) + goto out_free_aff; + + ret = irq_set_affinity_hint(irq, cpumask_of(aff->cpu)); + if (ret) + goto out_free_irq; + + ret = cpuhp_state_add_instance_nocalls(cpuhp_state_num, &aff->node); + if (ret) + goto out_free_irq; + + aff->irq = irq; + list_add(&aff->affinity_list, &dmc620_pmu_affinities); + + return aff; + +out_free_irq: + free_irq(irq, aff); +out_free_aff: + kfree(aff); + return ERR_PTR(ret); +} + +static int dmc620_pmu_get_affinity(struct dmc620_pmu *dmc620_pmu, int irq) +{ + struct dmc620_pmu_affinity *aff; + + mutex_lock(&dmc620_pmu_affinity_lock); + aff = __dmc620_pmu_get_affinity(irq); + mutex_unlock(&dmc620_pmu_affinity_lock); + + if (IS_ERR(aff)) + return PTR_ERR(aff); + + dmc620_pmu->affinity = aff; + mutex_lock(&dmc620_pmu_affinity_lock); + list_add_rcu(&dmc620_pmu->affinity_list, &aff->instance_list); + mutex_unlock(&dmc620_pmu_affinity_lock); + + return 0; +} + +static void dmc620_pmu_put_affinity(struct dmc620_pmu *dmc620_pmu) +{ + struct dmc620_pmu_affinity *aff = dmc620_pmu->affinity; + + mutex_lock(&dmc620_pmu_affinity_lock); + list_del_rcu(&dmc620_pmu->affinity_list); + + if (!refcount_dec_and_test(&aff->refcount)) { + mutex_unlock(&dmc620_pmu_affinity_lock); + return; + } + + list_del(&aff->affinity_list); + mutex_unlock(&dmc620_pmu_affinity_lock); + + free_irq(aff->irq, aff); + cpuhp_state_remove_instance_nocalls(cpuhp_state_num, &aff->node); + kfree(aff); +} + +static int dmc620_pmu_event_init(struct perf_event *event) +{ + struct dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + struct perf_event *sibling; + + if (event->attr.type != event->pmu->type) + return -ENOENT; + + /* + * DMC 620 PMUs are shared across all cpus and cannot + * support task bound and sampling events. + */ + if (is_sampling_event(event) || + event->attach_state & PERF_ATTACH_TASK) { + dev_dbg(dmc620_pmu->pmu.dev, + "Can't support per-task counters\n"); + return -EOPNOTSUPP; + } + + if (event->cpu < 0) { + dev_dbg(dmc620_pmu->pmu.dev, + "Per-task mode not supported\n"); + return -EOPNOTSUPP; + } + + /* + * Many perf core operations (eg. events rotation) operate on a + * single CPU context. This is obvious for CPU PMUs, where one + * expects the same sets of events being observed on all CPUs, + * but can lead to issues for off-core PMUs, where each + * event could be theoretically assigned to a different CPU. To + * mitigate this, we enforce CPU assignment to one, selected + * processor. + */ + event->cpu = dmc620_pmu->affinity->cpu; + + /* + * We must NOT create groups containing mixed PMUs, although software + * events are acceptable. + */ + if (event->group_leader->pmu != event->pmu && + !is_software_event(event->group_leader)) + return -EINVAL; + + for_each_sibling_event(sibling, event->group_leader) { + if (sibling->pmu != event->pmu && + !is_software_event(sibling)) + return -EINVAL; + } + + hwc->idx = -1; + return 0; +} + +static void dmc620_pmu_read(struct perf_event *event) +{ + dmc620_pmu_event_update(event); +} + +static void dmc620_pmu_start(struct perf_event *event, int flags) +{ + struct dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu); + + event->hw.state = 0; + dmc620_pmu_event_set_period(event); + + if (flags & PERF_EF_RELOAD) { + unsigned long prev_raw_count = + local64_read(&event->hw.prev_count); + + dmc620_pmu_creg_write(dmc620_pmu, + event->hw.idx, DMC620_PMU_COUNTER_VALUE_OFFSET, + (unsigned int)prev_raw_count); + } + dmc620_pmu_enable_counter(event); +} + +static void dmc620_pmu_stop(struct perf_event *event, int flags) +{ + if (event->hw.state & PERF_HES_STOPPED) + return; + + dmc620_pmu_disable_counter(event); + dmc620_pmu_event_update(event); + event->hw.state |= PERF_HES_STOPPED | PERF_HES_UPTODATE; +} + +static int dmc620_pmu_add(struct perf_event *event, int flags) +{ + struct dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + struct perf_event_attr *attr = &event->attr; + unsigned long reg; + int idx; + + idx = dmc620_get_event_idx(event); + if (idx < 0) + return idx; + + hwc->idx = idx; + dmc620_pmu->act_counter[idx] = event; + hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE; + + reg = ATTR_CFG_GET_FLD(attr, mask); + dmc620_pmu_creg_write(dmc620_pmu, + event->hw.idx, DMC620_PMU_COUNTER_MASK_31_00_OFFSET, + lower_32_bits(reg)); + dmc620_pmu_creg_write(dmc620_pmu, + event->hw.idx, DMC620_PMU_COUNTER_MASK_63_32_OFFSET, + upper_32_bits(reg)); + + reg = ATTR_CFG_GET_FLD(attr, match); + dmc620_pmu_creg_write(dmc620_pmu, + event->hw.idx, DMC620_PMU_COUNTER_MATCH_31_00_OFFSET, + lower_32_bits(reg)); + dmc620_pmu_creg_write(dmc620_pmu, + event->hw.idx, DMC620_PMU_COUNTER_MATCH_63_32_OFFSET, + upper_32_bits(reg)); + + reg = dmc620_event_to_counter_control(event); + dmc620_pmu_creg_write(dmc620_pmu, + event->hw.idx, DMC620_PMU_COUNTER_CONTROL_OFFSET, + (unsigned int)reg); + + if (flags & PERF_EF_START) + dmc620_pmu_start(event, PERF_EF_RELOAD); + + perf_event_update_userpage(event); + return 0; +} + +static void dmc620_pmu_del(struct perf_event *event, int flags) +{ + struct dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + int idx = hwc->idx; + + dmc620_pmu_stop(event, PERF_EF_UPDATE); + dmc620_pmu->act_counter[idx] = NULL; + clear_bit(idx, dmc620_pmu->used_mask); + perf_event_update_userpage(event); +} + +static int dmc620_pmu_cpu_teardown(unsigned int cpu, + struct hlist_node *node) +{ + struct dmc620_pmu_affinity *aff; + struct dmc620_pmu *dmc620_pmu; + unsigned int target; + + aff = hlist_entry_safe(node, struct dmc620_pmu_affinity, node); + if (cpu != aff->cpu) + return 0; + + target = cpumask_any_but(cpu_online_mask, cpu); + if (target >= nr_cpu_ids) + return 0; + + /* We're only reading, but this isn't the place to be involving RCU */ + mutex_lock(&dmc620_pmu_affinity_lock); + list_for_each_entry(dmc620_pmu, &aff->instance_list, affinity_list) + perf_pmu_migrate_context(&dmc620_pmu->pmu, aff->cpu, target); + mutex_unlock(&dmc620_pmu_affinity_lock); + + WARN_ON(irq_set_affinity_hint(aff->irq, cpumask_of(target))); + aff->cpu = target; + + return 0; +} + +static int dmc620_pmu_device_probe(struct platform_device *pdev) +{ + struct dmc620_pmu *dmc620_pmu; + struct resource *res; + char *name; + int irq; + int ret; + + dmc620_pmu = devm_kzalloc(&pdev->dev, + sizeof(struct dmc620_pmu), GFP_KERNEL); + if (!dmc620_pmu) + return -ENOMEM; + + dmc620_pmu->pdev = pdev; + platform_set_drvdata(pdev, dmc620_pmu); + + dmc620_pmu->pmu = (struct pmu) { + .capabilities = PERF_PMU_CAP_NO_EXCLUDE, + .task_ctx_nr = perf_invalid_context, + .event_init = dmc620_pmu_event_init, + .add = dmc620_pmu_add, + .del = dmc620_pmu_del, + .start = dmc620_pmu_start, + .stop = dmc620_pmu_stop, + .read = dmc620_pmu_read, + .attr_groups = dmc620_pmu_attr_groups, + }; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "failed to get IRQ (%d)\n", irq); + return irq; + } + + ret = dmc620_pmu_get_affinity(dmc620_pmu, irq); + if (ret) + return ret; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + dmc620_pmu->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(dmc620_pmu->base)) { + dev_err(&pdev->dev, + "ioremap failed for DMC-620 PMU resource\n"); + ret = PTR_ERR(dmc620_pmu->base); + goto out_teardown_dev; + } + + name = devm_kasprintf(&pdev->dev, GFP_KERNEL, + "%s_%llx", DMC620_PMUNAME, + (res->start) >> DMC620_PA_SHIFT); + if (!name) { + dev_err(&pdev->dev, + "Create name failed, PMU @%pa\n", &res->start); + goto out_teardown_dev; + } + + ret = perf_pmu_register(&dmc620_pmu->pmu, name, -1); + if (ret) + goto out_teardown_dev; + + return 0; + +out_teardown_dev: + dmc620_pmu_put_affinity(dmc620_pmu); + synchronize_rcu(); + return ret; +} + +static int dmc620_pmu_device_remove(struct platform_device *pdev) +{ + struct dmc620_pmu *dmc620_pmu = platform_get_drvdata(pdev); + + dmc620_pmu_put_affinity(dmc620_pmu); + + /* perf will synchronise RCU before devres can free dmc620_pmu */ + perf_pmu_unregister(&dmc620_pmu->pmu); + + return 0; +} + +static const struct acpi_device_id dmc620_acpi_match[] = { + { "ARMHD620", 0}, + {}, +}; +MODULE_DEVICE_TABLE(acpi, dmc620_acpi_match); +static struct platform_driver dmc620_pmu_driver = { + .driver = { + .name = DMC620_DRVNAME, + .acpi_match_table = ACPI_PTR(dmc620_acpi_match), + }, + .probe = dmc620_pmu_device_probe, + .remove = dmc620_pmu_device_remove, +}; + +static int __init dmc620_pmu_init(void) +{ + cpuhp_state_num = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, + DMC620_DRVNAME, + NULL, + dmc620_pmu_cpu_teardown); + if (cpuhp_state_num < 0) + return cpuhp_state_num; + + return platform_driver_register(&dmc620_pmu_driver); +} + +static void __exit dmc620_pmu_exit(void) +{ + platform_driver_unregister(&dmc620_pmu_driver); + cpuhp_remove_multi_state(cpuhp_state_num); +} + +module_init(dmc620_pmu_init); +module_exit(dmc620_pmu_exit); + +MODULE_DESCRIPTION("Perf driver for the Arm DMC-620 memory controller"); +MODULE_AUTHOR("Tuan Phan <tuanphan@os.amperecomputing.com"); +MODULE_LICENSE("GPL v2"); -- 2.7.4
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