[PATCH] perf: ampere: Add support for Ampere SoC PMUs
Ilkka Koskinen
ilkka at os.amperecomputing.com
Thu Apr 27 14:53:25 PDT 2023
Add support for Ampere SoC PMUs. This driver supports MCU PMU
available in the AmpereOne SoC.
Signed-off-by: Ilkka Koskinen <ilkka at os.amperecomputing.com>
---
.../admin-guide/perf/ampere-soc-pmu.rst | 36 +
Documentation/admin-guide/perf/index.rst | 1 +
drivers/perf/Kconfig | 10 +
drivers/perf/Makefile | 1 +
drivers/perf/ampere_soc_pmu.c | 724 ++++++++++++++++++
5 files changed, 772 insertions(+)
create mode 100644 Documentation/admin-guide/perf/ampere-soc-pmu.rst
create mode 100644 drivers/perf/ampere_soc_pmu.c
diff --git a/Documentation/admin-guide/perf/ampere-soc-pmu.rst b/Documentation/admin-guide/perf/ampere-soc-pmu.rst
new file mode 100644
index 000000000000..5161fbd1c548
--- /dev/null
+++ b/Documentation/admin-guide/perf/ampere-soc-pmu.rst
@@ -0,0 +1,36 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+============================================
+Ampere SoC Performance Monitoring Unit (PMU)
+============================================
+
+Ampere SoC PMU is a generic PMU IP. At the first phase it's used for counting
+MCU events on AmpereOne.
+
+MCU PMU events
+--------------
+
+The PMU driver registers a PMU device for every supported PMU instance on each
+SoC. See /sys/devices/AMPC0100:<nn>/.
+
+The PMU driver supports setting filters for "rank", "bank", and "threshold". The
+filter settings are device specific and shared between all the relevant events.
+The default value for all the filters is zero. The filters can be modified by
+setting them with the last event of the particular device. All the previous
+settings are overwritten.
+
+
+Example for perf tool use::
+
+ / # perf list mcu
+ mcu0/cycle-count [Kernel PMU event]
+ <...>
+ mcu16/cycle-count [Kernel PMU event]
+ <...>
+
+ / # perf stat -a -e mcu0/cycle-count,bank=5/,mcu0/dfi-cmd,threshold=16,rank=8/,mcu1/dfi-cmd/ \
+ sleep 1
+
+Note, as none of the filters was set for mcu1, the default value is assigned to
+them. For mcu0, bank setting will be overwritten with the default value since
+it wasn't set with the last mcu0 event.
diff --git a/Documentation/admin-guide/perf/index.rst b/Documentation/admin-guide/perf/index.rst
index 9de64a40adab..8de9d253ae81 100644
--- a/Documentation/admin-guide/perf/index.rst
+++ b/Documentation/admin-guide/perf/index.rst
@@ -21,3 +21,4 @@ Performance monitor support
alibaba_pmu
nvidia-pmu
meson-ddr-pmu
+ ampere-soc-pmu
diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig
index 711f82400086..6551005aaa04 100644
--- a/drivers/perf/Kconfig
+++ b/drivers/perf/Kconfig
@@ -209,6 +209,16 @@ config MARVELL_CN10K_DDR_PMU
Enable perf support for Marvell DDR Performance monitoring
event on CN10K platform.
+config AMPERE_SOC_PMU
+ tristate "Ampere SoC PMU"
+ depends on ARM64 && ACPI
+ help
+ Enable support for Ampere SoC performance counters used on
+ Ampere SoCs.
+
+ The SoC PMU can support multiple different PMU types. At the first
+ phase it supports MCU PMU available on AmpereOne.
+
source "drivers/perf/arm_cspmu/Kconfig"
source "drivers/perf/amlogic/Kconfig"
diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile
index dabc859540ce..17be9b0f75f8 100644
--- a/drivers/perf/Makefile
+++ b/drivers/perf/Makefile
@@ -24,3 +24,4 @@ obj-$(CONFIG_APPLE_M1_CPU_PMU) += apple_m1_cpu_pmu.o
obj-$(CONFIG_ALIBABA_UNCORE_DRW_PMU) += alibaba_uncore_drw_pmu.o
obj-$(CONFIG_ARM_CORESIGHT_PMU_ARCH_SYSTEM_PMU) += arm_cspmu/
obj-$(CONFIG_MESON_DDR_PMU) += amlogic/
+obj-$(CONFIG_AMPERE_SOC_PMU) += ampere_soc_pmu.o
diff --git a/drivers/perf/ampere_soc_pmu.c b/drivers/perf/ampere_soc_pmu.c
new file mode 100644
index 000000000000..0591e0e4fbd2
--- /dev/null
+++ b/drivers/perf/ampere_soc_pmu.c
@@ -0,0 +1,724 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Ampere SoC PMU (Performance Monitor Unit)
+ *
+ * Copyright (c) 2023, Ampere Computing LLC
+ */
+
+#include <linux/acpi.h>
+#include <linux/cpuhotplug.h>
+#include <linux/cpumask.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/perf_event.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define SOC_PMEVCNTR0_LO 0x000
+#define SOC_PMEVCNTR0_HI 0x004
+#define SOC_PMCCNTR_LO 0x0F8
+#define SOC_PMCCNTR_HI 0x0FC
+
+#define SOC_PMEVTYPER0 0x400
+
+#define SOC_PMELCSR 0xA10
+
+#define SOC_PMCNTENSET 0xC00
+#define SOC_PMCNTENCLR 0xC20
+#define SOC_PMINTENSET 0xC40
+#define SOC_PMINTENCLR 0xC60
+#define SOC_PMOVSCLR 0xC80
+#define SOC_PMOVSSET 0xCC0
+
+#define SOC_PMAUXR0 0xD80
+#define SOC_PMAUXR1 0xD84
+#define SOC_PMAUXR2 0xD88
+#define SOC_PMAUXR3 0xD8C
+
+#define SOC_PMCFGR 0xE00
+#define SOC_PMCR 0xE04
+#define PMU_PMCR_E BIT(0)
+#define PMU_PMCR_P BIT(1)
+
+#define SOC_PMAUTHSTATUS 0xFB8
+#define SOC_PMDEVARCH 0xFBC
+#define SOC_PMDEVTYPE 0xFCC
+#define SOC_PMPIDR4 0xFD0
+#define SOC_PMPIDR0 0xFE0
+#define SOC_PMPIDR1 0xFE4
+#define SOC_PMPIDR2 0xFE8
+#define SOC_PMPIDR3 0xFEC
+#define SOC_PMCIDR0 0xFF0
+#define SOC_PMCIDR1 0xFF4
+#define SOC_PMCIDR2 0xFF8
+#define SOC_PMCIDR3 0xFFC
+
+#define SOC_ID_MASK 0xFFF
+#define SOC_VERSION_MASK 0xFF000
+#define SOC_CYCLE_COUNTER BIT(14)
+#define SOC_NR_COUNTERS_MASK 0xF
+
+#define SOC_PMEVCNTR_LOn(n) (SOC_PMEVCNTR0_LO + (n) * 8)
+#define SOC_PMEVCNTR_HIn(n) (SOC_PMEVCNTR0_HI + (n) * 8)
+#define SOC_PMEVTYPERn(n) (SOC_PMEVTYPER0 + (n) * 4)
+
+#define SOC_CYCLE_COUNTER_BIT BIT(31)
+#define SOC_MAX_COUNTERS 4
+#define SOC_CYCLE_COUNTER_IDX SOC_MAX_COUNTERS
+#define SOC_CYCLE_COUNTER_EVENT 0x100
+
+#define SOC_MAX_PERIOD 0xFFFFFFFFFFFFFFFFULL
+
+struct ampere_pmu {
+ int id;
+ int version;
+
+ void __iomem *base;
+ int irq;
+
+ int nr_counters;
+
+ /* Number of generic counters + optional cycle counter */
+ DECLARE_BITMAP(counter_mask, SOC_MAX_COUNTERS + 1);
+ struct perf_event *counters[SOC_MAX_COUNTERS + 1];
+ bool cycle_exists;
+
+ int cpu;
+ struct hlist_node node;
+ struct pmu pmu;
+ struct device *dev;
+};
+
+static int cpuhp_state_num;
+
+#define to_ampere_pmu(_pmu) container_of(_pmu, struct ampere_pmu, pmu)
+
+#define SOC_CONFIG_EVENTID GENMASK(8, 0)
+#define SOC_CONFIG_THRESHOLD GENMASK(7, 0)
+#define SOC_CONFIG_RANK GENMASK(23, 8)
+#define SOC_CONFIG_BANK GENMASK(31, 0)
+
+#define SOC_EVENT_EVENTID(event) FIELD_GET(SOC_CONFIG_EVENTID, (event)->attr.config)
+#define SOC_EVENT_THRESHOLD(event) FIELD_GET(SOC_CONFIG_THRESHOLD, (event)->attr.config1)
+#define SOC_EVENT_RANK(event) FIELD_GET(SOC_CONFIG_RANK, (event)->attr.config1)
+#define SOC_EVENT_BANK(event) FIELD_GET(SOC_CONFIG_BANK, (event)->attr.config2)
+
+#define AMPERE_PMU_EVENT_ATTR(_name, _event) \
+ PMU_EVENT_ATTR_ID(_name, ampere_pmu_event_show, _event)
+
+#define AMPERE_PMU_EVENT_CYCLE(_name) \
+ AMPERE_PMU_EVENT_ATTR(_name, SOC_CYCLE_COUNTER_EVENT)
+
+#define AMPERE_PMU_FORMAT_ATTR(_name, _config) \
+ (&((struct dev_ext_attribute[]) {{ \
+ .attr = __ATTR(_name, 0444, ampere_pmu_format_show, NULL), \
+ .var = (void *) _config \
+ }})[0].attr.attr)
+
+static ssize_t ampere_pmu_format_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct dev_ext_attribute *eattr =
+ container_of(attr, struct dev_ext_attribute, attr);
+
+ return sysfs_emit(buf, "%s\n", (char *)eattr->var);
+}
+
+static struct attribute *ampere_pmu_format_attrs[] = {
+ AMPERE_PMU_FORMAT_ATTR(event, "config:0-8"),
+ AMPERE_PMU_FORMAT_ATTR(threshold, "config1:0-7"),
+ AMPERE_PMU_FORMAT_ATTR(rank, "config1:8-23"),
+ AMPERE_PMU_FORMAT_ATTR(bank, "config2:0-31"),
+ NULL,
+};
+
+static const struct attribute_group ampere_pmu_format_attr_group = {
+ .name = "format",
+ .attrs = ampere_pmu_format_attrs,
+};
+
+static ssize_t ampere_pmu_event_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct perf_pmu_events_attr *pmu_attr =
+ container_of(attr, struct perf_pmu_events_attr, attr);
+
+ return sysfs_emit(buf, "event=0x%llx\n", pmu_attr->id);
+}
+
+static struct attribute *ampere_mcu_pmu_events_attrs[] = {
+ AMPERE_PMU_EVENT_ATTR(cycle_count, 0x00),
+ AMPERE_PMU_EVENT_ATTR(act_sent, 0x01),
+ AMPERE_PMU_EVENT_ATTR(pre_sent, 0x02),
+ AMPERE_PMU_EVENT_ATTR(rd_sent, 0x03),
+ AMPERE_PMU_EVENT_ATTR(rda_sent, 0x04),
+ AMPERE_PMU_EVENT_ATTR(wr_sent, 0x05),
+ AMPERE_PMU_EVENT_ATTR(wra_sent, 0x06),
+ AMPERE_PMU_EVENT_ATTR(pd_entry_vld, 0x07),
+ AMPERE_PMU_EVENT_ATTR(sref_entry_vld, 0x08),
+ AMPERE_PMU_EVENT_ATTR(prea_sent, 0x09),
+ AMPERE_PMU_EVENT_ATTR(pre_sb_sent, 0x0a),
+ AMPERE_PMU_EVENT_ATTR(ref_sent, 0x0b),
+ AMPERE_PMU_EVENT_ATTR(rfm_sent, 0x0c),
+ AMPERE_PMU_EVENT_ATTR(ref_sb_sent, 0x0d),
+ AMPERE_PMU_EVENT_ATTR(rfm_sb_sent, 0x0e),
+ AMPERE_PMU_EVENT_ATTR(rd_rda_sent, 0x0f),
+ AMPERE_PMU_EVENT_ATTR(wr_wra_sent, 0x10),
+ AMPERE_PMU_EVENT_ATTR(raw_hazard, 0x11),
+ AMPERE_PMU_EVENT_ATTR(war_hazard, 0x12),
+ AMPERE_PMU_EVENT_ATTR(waw_hazard, 0x13),
+ AMPERE_PMU_EVENT_ATTR(rar_hazard, 0x14),
+ AMPERE_PMU_EVENT_ATTR(raw_war_waw_hazard, 0x15),
+ AMPERE_PMU_EVENT_ATTR(hprd_lprd_wr_req_vld, 0x16),
+ AMPERE_PMU_EVENT_ATTR(lprd_req_vld, 0x17),
+ AMPERE_PMU_EVENT_ATTR(hprd_req_vld, 0x18),
+ AMPERE_PMU_EVENT_ATTR(hprd_lprd_req_vld, 0x19),
+ AMPERE_PMU_EVENT_ATTR(prefetch_tgt, 0x1a),
+ AMPERE_PMU_EVENT_ATTR(wr_req_vld, 0x1b),
+ AMPERE_PMU_EVENT_ATTR(partial_wr_req_vld, 0x1c),
+ AMPERE_PMU_EVENT_ATTR(rd_retry, 0x1d),
+ AMPERE_PMU_EVENT_ATTR(wr_retry, 0x1e),
+ AMPERE_PMU_EVENT_ATTR(retry_gnt, 0x1f),
+ AMPERE_PMU_EVENT_ATTR(rank_change, 0x20),
+ AMPERE_PMU_EVENT_ATTR(dir_change, 0x21),
+ AMPERE_PMU_EVENT_ATTR(rank_dir_change, 0x22),
+ AMPERE_PMU_EVENT_ATTR(rank_active, 0x23),
+ AMPERE_PMU_EVENT_ATTR(rank_idle, 0x24),
+ AMPERE_PMU_EVENT_ATTR(rank_pd, 0x25),
+ AMPERE_PMU_EVENT_ATTR(rank_sref, 0x26),
+ AMPERE_PMU_EVENT_ATTR(queue_fill_gt_thresh, 0x27),
+ AMPERE_PMU_EVENT_ATTR(queue_rds_gt_thresh, 0x28),
+ AMPERE_PMU_EVENT_ATTR(queue_wrs_gt_thresh, 0x29),
+ AMPERE_PMU_EVENT_ATTR(phy_updt_complt, 0x2a),
+ AMPERE_PMU_EVENT_ATTR(tz_fail, 0x2b),
+ AMPERE_PMU_EVENT_ATTR(dram_errc, 0x2c),
+ AMPERE_PMU_EVENT_ATTR(dram_errd, 0x2d),
+ AMPERE_PMU_EVENT_ATTR(read_data_return, 0x32),
+ AMPERE_PMU_EVENT_ATTR(chi_wr_data_delta, 0x33),
+ AMPERE_PMU_EVENT_ATTR(zq_start, 0x34),
+ AMPERE_PMU_EVENT_ATTR(zq_latch, 0x35),
+ AMPERE_PMU_EVENT_ATTR(wr_fifo_full, 0x36),
+ AMPERE_PMU_EVENT_ATTR(info_fifo_full, 0x37),
+ AMPERE_PMU_EVENT_ATTR(cmd_fifo_full, 0x38),
+ AMPERE_PMU_EVENT_ATTR(dfi_nop, 0x39),
+ AMPERE_PMU_EVENT_ATTR(dfi_cmd, 0x3a),
+ AMPERE_PMU_EVENT_ATTR(rd_run_len, 0x3b),
+ AMPERE_PMU_EVENT_ATTR(wr_run_len, 0x3c),
+
+ AMPERE_PMU_EVENT_CYCLE(cycle),
+ NULL,
+};
+
+static umode_t ampere_pmu_event_is_visible(struct kobject *kobj,
+ struct attribute *attr, int unused)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct ampere_pmu *apmu = to_ampere_pmu(dev_get_drvdata(dev));
+ struct perf_pmu_events_attr *eattr =
+ container_of(attr, struct perf_pmu_events_attr, attr.attr);
+
+ if (eattr->id == SOC_CYCLE_COUNTER_EVENT && !apmu->cycle_exists)
+ return 0;
+
+ return attr->mode;
+}
+
+static const struct attribute_group ampere_pmu_events_attrs_group = {
+ .name = "events",
+ .attrs = ampere_mcu_pmu_events_attrs,
+ .is_visible = ampere_pmu_event_is_visible,
+};
+
+static ssize_t ampere_cpumask_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ampere_pmu *apmu = to_ampere_pmu(dev_get_drvdata(dev));
+
+ return cpumap_print_to_pagebuf(true, buf, cpumask_of(apmu->cpu));
+}
+
+static struct device_attribute ampere_pmu_cpumask_attr =
+ __ATTR(cpumask, 0444, ampere_cpumask_show, NULL);
+
+static struct attribute *ampere_pmu_cpumask_attrs[] = {
+ &ere_pmu_cpumask_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group ampere_pmu_cpumask_attr_group = {
+ .attrs = ampere_pmu_cpumask_attrs,
+};
+
+static const struct attribute_group *ampere_pmu_attr_groups[] = {
+ &ere_pmu_events_attrs_group,
+ &ere_pmu_format_attr_group,
+ &ere_pmu_cpumask_attr_group,
+ NULL,
+};
+
+static void ampere_pmu_event_config(struct perf_event *event)
+{
+ struct ampere_pmu *apmu = to_ampere_pmu(event->pmu);
+
+ writel(SOC_EVENT_THRESHOLD(event), apmu->base + SOC_PMAUXR0);
+ writel(SOC_EVENT_RANK(event), apmu->base + SOC_PMAUXR1);
+ writel(SOC_EVENT_BANK(event), apmu->base + SOC_PMAUXR2);
+}
+
+static inline u64 ampere_pmu_read_counter(struct ampere_pmu *apmu, int idx)
+{
+ u32 lo, hi, reg_high, reg_low;
+
+ if (idx == SOC_CYCLE_COUNTER_IDX) {
+ reg_low = SOC_PMCCNTR_LO;
+ reg_high = SOC_PMCCNTR_HI;
+ } else {
+ reg_low = SOC_PMEVCNTR_LOn(idx);
+ reg_high = SOC_PMEVCNTR_HIn(idx);
+ }
+
+ do {
+ hi = readl(apmu->base + reg_high);
+ lo = readl(apmu->base + reg_low);
+ } while (hi != readl(apmu->base + reg_high));
+
+ return (((u64)hi << 32) | lo);
+}
+
+static inline void ampere_pmu_write_counter(struct ampere_pmu *apmu, int idx, u64 val)
+{
+ if (idx == SOC_CYCLE_COUNTER_IDX) {
+ writel(lower_32_bits(val), apmu->base + SOC_PMCCNTR_LO);
+ writel(upper_32_bits(val), apmu->base + SOC_PMCCNTR_HI);
+ } else {
+ writel(lower_32_bits(val), apmu->base + SOC_PMEVCNTR_LOn(idx));
+ writel(upper_32_bits(val), apmu->base + SOC_PMEVCNTR_HIn(idx));
+ }
+}
+
+static int ampere_get_counter_idx(struct perf_event *event)
+{
+ struct ampere_pmu *apmu = to_ampere_pmu(event->pmu);
+ int idx, eventid = SOC_EVENT_EVENTID(event);
+
+ if (eventid == SOC_CYCLE_COUNTER_EVENT) {
+ if (test_and_set_bit(SOC_CYCLE_COUNTER_IDX, apmu->counter_mask))
+ return -ENOSPC;
+
+ return SOC_CYCLE_COUNTER_IDX;
+ }
+
+ for (idx = 0; idx < apmu->nr_counters; idx++)
+ if (!test_and_set_bit(idx, apmu->counter_mask))
+ return idx;
+
+ return -ENOSPC;
+}
+
+static void ampere_pmu_enable(struct pmu *pmu)
+{
+ struct ampere_pmu *apmu = to_ampere_pmu(pmu);
+ u32 val;
+
+ val = readl(apmu->base + SOC_PMCR);
+ val |= PMU_PMCR_E;
+ writel(val, apmu->base + SOC_PMCR);
+}
+
+static void ampere_pmu_disable(struct pmu *pmu)
+{
+ struct ampere_pmu *apmu = to_ampere_pmu(pmu);
+ u32 val;
+
+ val = readl(apmu->base + SOC_PMCR);
+ val &= ~PMU_PMCR_E;
+ writel(val, apmu->base + SOC_PMCR);
+}
+
+static void ampere_pmu_enable_event(struct perf_event *event)
+{
+ struct ampere_pmu *apmu = to_ampere_pmu(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+ u32 val, cnt_bit;
+ int eventid = SOC_EVENT_EVENTID(event);
+
+ if (eventid == SOC_CYCLE_COUNTER_EVENT) {
+ cnt_bit = SOC_CYCLE_COUNTER_BIT;
+ } else {
+ cnt_bit = BIT(hw->idx);
+ writel(eventid, apmu->base + SOC_PMEVTYPERn(hw->idx));
+ }
+
+ val = readl(apmu->base + SOC_PMCNTENSET);
+ val |= cnt_bit;
+ writel(val, apmu->base + SOC_PMCNTENSET);
+
+ val = readl(apmu->base + SOC_PMINTENSET);
+ val |= cnt_bit;
+ writel(val, apmu->base + SOC_PMINTENSET);
+}
+
+static void ampere_pmu_disable_event(struct perf_event *event)
+{
+ struct ampere_pmu *apmu = to_ampere_pmu(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+ u32 val, cnt_bit;
+ int eventid = SOC_EVENT_EVENTID(event);
+
+ if (eventid == SOC_CYCLE_COUNTER_EVENT)
+ cnt_bit = SOC_CYCLE_COUNTER_BIT;
+ else
+ cnt_bit = BIT(hw->idx);
+
+ val = readl(apmu->base + SOC_PMCNTENCLR);
+ val |= cnt_bit;
+ writel(val, apmu->base + SOC_PMCNTENCLR);
+
+ val = readl(apmu->base + SOC_PMINTENSET);
+ val |= cnt_bit;
+ writel(val, apmu->base + SOC_PMINTENSET);
+}
+
+static void ampere_perf_event_set_period(struct perf_event *event)
+{
+ struct ampere_pmu *apmu = to_ampere_pmu(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+
+ /*
+ * With 64 bit counter, we don't expect the counter to
+ * wrap past its initial value.
+ */
+ u64 val = 1ULL << 31;
+
+ local64_set(&hw->prev_count, val);
+ ampere_pmu_write_counter(apmu, hw->idx, val);
+}
+
+static void ampere_perf_event_update(struct perf_event *event)
+{
+ struct ampere_pmu *apmu = to_ampere_pmu(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+ u64 prev_count, new_count;
+
+ do {
+ prev_count = local64_read(&hw->prev_count);
+ new_count = ampere_pmu_read_counter(apmu, hw->idx);
+ } while (local64_xchg(&hw->prev_count, new_count) != prev_count);
+
+ local64_add((new_count - prev_count) & SOC_MAX_PERIOD,
+ &event->count);
+}
+
+static void ampere_perf_read(struct perf_event *event)
+{
+ ampere_perf_event_update(event);
+}
+
+static void ampere_perf_start(struct perf_event *event, int flags)
+{
+ struct hw_perf_event *hw = &event->hw;
+
+ if (WARN_ON_ONCE(!(hw->state & PERF_HES_STOPPED)))
+ return;
+
+ if (flags & PERF_EF_RELOAD)
+ WARN_ON_ONCE(!(hw->state & PERF_HES_UPTODATE));
+
+ hw->state = 0;
+ ampere_perf_event_set_period(event);
+
+ ampere_pmu_enable_event(event);
+ perf_event_update_userpage(event);
+}
+
+static void ampere_perf_stop(struct perf_event *event, int flags)
+{
+ struct hw_perf_event *hw = &event->hw;
+
+ ampere_pmu_disable_event(event);
+
+ WARN_ON_ONCE(hw->state & PERF_HES_STOPPED);
+ hw->state |= PERF_HES_STOPPED;
+
+ ampere_perf_read(event);
+ hw->state |= PERF_HES_UPTODATE;
+}
+
+static int ampere_perf_validate_group(struct perf_event *event)
+{
+ struct perf_event *sibling, *leader = event->group_leader;
+ struct ampere_pmu *apmu = to_ampere_pmu(event->pmu);
+ int counters = 0;
+
+ if (leader == event)
+ return 0;
+
+ if (event->pmu != leader->pmu && !is_software_event(leader))
+ return -EINVAL;
+
+ for_each_sibling_event(sibling, leader) {
+ if (is_software_event(sibling))
+ continue;
+ if (sibling->pmu != event->pmu)
+ return -EINVAL;
+ counters++;
+ }
+
+ if (counters > apmu->nr_counters)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int ampere_perf_event_init(struct perf_event *event)
+{
+ struct ampere_pmu *apmu = to_ampere_pmu(event->pmu);
+
+ if (event->attr.type != event->pmu->type)
+ return -ENOENT;
+
+ if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
+ return -EINVAL;
+
+ if (event->cpu < 0)
+ return -EINVAL;
+
+ event->cpu = apmu->cpu;
+
+ return ampere_perf_validate_group(event);
+}
+
+
+static int ampere_perf_add(struct perf_event *event, int flags)
+{
+ struct ampere_pmu *apmu = to_ampere_pmu(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+ int idx;
+
+ idx = ampere_get_counter_idx(event);
+ if (idx < 0)
+ return idx;
+
+ apmu->counters[idx] = event;
+ event->hw.idx = idx;
+
+ ampere_pmu_event_config(event);
+
+ hw->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
+ if (flags & PERF_EF_START)
+ ampere_perf_start(event, PERF_EF_RELOAD);
+
+ /* Propagate our changes to the userspace mapping. */
+ perf_event_update_userpage(event);
+
+ return 0;
+}
+
+static void ampere_perf_del(struct perf_event *event, int flags)
+{
+ struct ampere_pmu *apmu = to_ampere_pmu(event->pmu);
+ struct hw_perf_event *hw = &event->hw;
+ int idx = hw->idx;
+
+ ampere_perf_stop(event, PERF_EF_UPDATE);
+
+ apmu->counters[idx] = NULL;
+ clear_bit(idx, apmu->counter_mask);
+
+ perf_event_update_userpage(event);
+}
+
+static int ampere_pmu_get_version(struct ampere_pmu *apmu)
+{
+ u32 reg;
+
+ reg = readl(apmu->base + SOC_PMDEVARCH);
+ apmu->id = reg & SOC_ID_MASK;
+ apmu->version = reg & SOC_VERSION_MASK;
+
+ reg = readl(apmu->base + SOC_PMCFGR);
+ apmu->cycle_exists = reg & SOC_CYCLE_COUNTER;
+ apmu->nr_counters = reg & SOC_NR_COUNTERS_MASK;
+
+ if (apmu->nr_counters > SOC_MAX_COUNTERS) {
+ dev_err(apmu->dev, "Unsupported type (%x, %x, counters %d\n",
+ apmu->id, apmu->version, apmu->nr_counters);
+ return -EOPNOTSUPP;
+ }
+
+ return 0;
+}
+
+static irqreturn_t ampere_pmu_handle_irq(int irq, void *dev_id)
+{
+ struct ampere_pmu *apmu = dev_id;
+ u32 status;
+ int idx, ret = IRQ_NONE;
+
+ status = readl(apmu->base + SOC_PMOVSSET);
+ if (!status)
+ goto out;
+
+ writel(status, apmu->base + SOC_PMOVSCLR);
+
+ for (idx = 0; idx < apmu->nr_counters; idx++) {
+ struct perf_event *event = apmu->counters[idx];
+ int overflowed = status & BIT(idx);
+
+ /* Ignore if we don't have an event. */
+ if (event && overflowed) {
+ ampere_perf_event_update(event);
+ ampere_perf_event_set_period(event);
+ ret = IRQ_HANDLED;
+ }
+ }
+
+ if (apmu->counters[SOC_CYCLE_COUNTER_IDX] &&
+ status & SOC_CYCLE_COUNTER_BIT) {
+ ampere_perf_event_update(apmu->counters[SOC_CYCLE_COUNTER_IDX]);
+ ampere_perf_event_set_period(apmu->counters[SOC_CYCLE_COUNTER_IDX]);
+ ret = IRQ_HANDLED;
+ }
+
+out:
+ ampere_pmu_enable(&apmu->pmu);
+ return ret;
+}
+
+static int ampere_pmu_probe(struct platform_device *pdev)
+{
+ struct ampere_pmu *apmu;
+ static atomic_t id;
+ char *name;
+ int ret = 0;
+
+ apmu = devm_kzalloc(&pdev->dev, sizeof(*apmu), GFP_KERNEL);
+ if (!apmu)
+ return -ENOMEM;
+
+ apmu->dev = &pdev->dev;
+ platform_set_drvdata(pdev, apmu);
+
+ apmu->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(apmu->base))
+ return PTR_ERR(apmu->base);
+
+ apmu->cpu = cpumask_local_spread(0, dev_to_node(apmu->dev));
+
+ apmu->irq = platform_get_irq(pdev, 0);
+ if (apmu->irq < 0)
+ return apmu->irq;
+
+ ret = devm_request_irq(&pdev->dev, apmu->irq, ampere_pmu_handle_irq,
+ IRQF_NOBALANCING | IRQF_SHARED,
+ pdev->name, apmu);
+ if (ret)
+ return ret;
+
+ ret = irq_set_affinity(apmu->irq, cpumask_of(apmu->cpu));
+ if (ret)
+ return ret;
+
+ ret = ampere_pmu_get_version(apmu);
+ if (ret)
+ return ret;
+
+ apmu->pmu = (struct pmu) {
+ .module = THIS_MODULE,
+ .attr_groups = ampere_pmu_attr_groups,
+ .task_ctx_nr = perf_invalid_context,
+ .pmu_enable = ampere_pmu_enable,
+ .pmu_disable = ampere_pmu_disable,
+ .event_init = ampere_perf_event_init,
+ .add = ampere_perf_add,
+ .del = ampere_perf_del,
+ .start = ampere_perf_start,
+ .stop = ampere_perf_stop,
+ .read = ampere_perf_read,
+ .capabilities = PERF_PMU_CAP_NO_EXCLUDE,
+ };
+
+ name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "mcu%d",
+ atomic_fetch_inc(&id));
+ if (!name)
+ return -ENOMEM;
+
+ ret = cpuhp_state_add_instance(cpuhp_state_num, &apmu->node);
+ if (ret) {
+ dev_err(&pdev->dev, "Error %d registering hotplug", ret);
+ return ret;
+ }
+
+ ret = perf_pmu_register(&apmu->pmu, name, -1);
+ if (ret)
+ cpuhp_state_remove_instance(cpuhp_state_num, &apmu->node);
+
+ return ret;
+}
+
+static int ampere_pmu_remove(struct platform_device *pdev)
+{
+ struct ampere_pmu *apmu = platform_get_drvdata(pdev);
+
+ cpuhp_state_remove_instance(cpuhp_state_num, &apmu->node);
+ perf_pmu_unregister(&apmu->pmu);
+ return 0;
+}
+
+static const struct acpi_device_id ampere_pmu_acpi_match[] = {
+ {"AMPC0100", 0},
+ {},
+};
+MODULE_DEVICE_TABLE(acpi, ampere_pmu_acpi_match);
+
+static struct platform_driver ampere_soc_pmu_driver = {
+ .driver = {
+ .name = "ampere-soc-pmu",
+ .acpi_match_table = ACPI_PTR(ampere_pmu_acpi_match),
+ },
+ .probe = ampere_pmu_probe,
+ .remove = ampere_pmu_remove,
+};
+
+static int ampere_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
+{
+ struct ampere_pmu *apmu = hlist_entry_safe(node, struct ampere_pmu, node);
+ unsigned int target;
+
+ if (cpu != apmu->cpu)
+ return 0;
+
+ target = cpumask_any_but(cpu_online_mask, cpu);
+ if (target >= nr_cpu_ids)
+ return 0;
+
+ perf_pmu_migrate_context(&apmu->pmu, cpu, target);
+ if (apmu->irq)
+ irq_set_affinity(apmu->irq, cpumask_of(apmu->cpu));
+
+ apmu->cpu = target;
+ return 0;
+}
+
+static int __init ampere_soc_pmu_init(void)
+{
+ cpuhp_state_num = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
+ "ampere-soc-pmu", NULL,
+ ampere_pmu_offline_cpu);
+ if (cpuhp_state_num < 0)
+ return cpuhp_state_num;
+
+ return platform_driver_register(&ere_soc_pmu_driver);
+}
+
+static void __exit ampere_soc_pmu_exit(void)
+{
+ platform_driver_unregister(&ere_soc_pmu_driver);
+ cpuhp_remove_multi_state(cpuhp_state_num);
+}
+
+module_init(ampere_soc_pmu_init);
+module_exit(ampere_soc_pmu_exit);
+
+MODULE_LICENSE("GPL");
--
2.39.2
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