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Diffstat (limited to 'drivers/perf/fsl_imx8_ddr_perf.c')
-rw-r--r--drivers/perf/fsl_imx8_ddr_perf.c812
1 files changed, 812 insertions, 0 deletions
diff --git a/drivers/perf/fsl_imx8_ddr_perf.c b/drivers/perf/fsl_imx8_ddr_perf.c
new file mode 100644
index 000000000..a4cda73b8
--- /dev/null
+++ b/drivers/perf/fsl_imx8_ddr_perf.c
@@ -0,0 +1,812 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2017 NXP
+ * Copyright 2016 Freescale Semiconductor, Inc.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/perf_event.h>
+#include <linux/slab.h>
+
+#define COUNTER_CNTL 0x0
+#define COUNTER_READ 0x20
+
+#define COUNTER_DPCR1 0x30
+
+#define CNTL_OVER 0x1
+#define CNTL_CLEAR 0x2
+#define CNTL_EN 0x4
+#define CNTL_EN_MASK 0xFFFFFFFB
+#define CNTL_CLEAR_MASK 0xFFFFFFFD
+#define CNTL_OVER_MASK 0xFFFFFFFE
+
+#define CNTL_CP_SHIFT 16
+#define CNTL_CP_MASK (0xFF << CNTL_CP_SHIFT)
+#define CNTL_CSV_SHIFT 24
+#define CNTL_CSV_MASK (0xFFU << CNTL_CSV_SHIFT)
+
+#define EVENT_CYCLES_ID 0
+#define EVENT_CYCLES_COUNTER 0
+#define NUM_COUNTERS 4
+
+/* For removing bias if cycle counter CNTL.CP is set to 0xf0 */
+#define CYCLES_COUNTER_MASK 0x0FFFFFFF
+#define AXI_MASKING_REVERT 0xffff0000 /* AXI_MASKING(MSB 16bits) + AXI_ID(LSB 16bits) */
+
+#define to_ddr_pmu(p) container_of(p, struct ddr_pmu, pmu)
+
+#define DDR_PERF_DEV_NAME "imx8_ddr"
+#define DDR_CPUHP_CB_NAME DDR_PERF_DEV_NAME "_perf_pmu"
+
+static DEFINE_IDA(ddr_ida);
+
+/* DDR Perf hardware feature */
+#define DDR_CAP_AXI_ID_FILTER 0x1 /* support AXI ID filter */
+#define DDR_CAP_AXI_ID_FILTER_ENHANCED 0x3 /* support enhanced AXI ID filter */
+
+struct fsl_ddr_devtype_data {
+ unsigned int quirks; /* quirks needed for different DDR Perf core */
+ const char *identifier; /* system PMU identifier for userspace */
+};
+
+static const struct fsl_ddr_devtype_data imx8_devtype_data;
+
+static const struct fsl_ddr_devtype_data imx8m_devtype_data = {
+ .quirks = DDR_CAP_AXI_ID_FILTER,
+};
+
+static const struct fsl_ddr_devtype_data imx8mq_devtype_data = {
+ .quirks = DDR_CAP_AXI_ID_FILTER,
+ .identifier = "i.MX8MQ",
+};
+
+static const struct fsl_ddr_devtype_data imx8mm_devtype_data = {
+ .quirks = DDR_CAP_AXI_ID_FILTER,
+ .identifier = "i.MX8MM",
+};
+
+static const struct fsl_ddr_devtype_data imx8mn_devtype_data = {
+ .quirks = DDR_CAP_AXI_ID_FILTER,
+ .identifier = "i.MX8MN",
+};
+
+static const struct fsl_ddr_devtype_data imx8mp_devtype_data = {
+ .quirks = DDR_CAP_AXI_ID_FILTER_ENHANCED,
+ .identifier = "i.MX8MP",
+};
+
+static const struct of_device_id imx_ddr_pmu_dt_ids[] = {
+ { .compatible = "fsl,imx8-ddr-pmu", .data = &imx8_devtype_data},
+ { .compatible = "fsl,imx8m-ddr-pmu", .data = &imx8m_devtype_data},
+ { .compatible = "fsl,imx8mq-ddr-pmu", .data = &imx8mq_devtype_data},
+ { .compatible = "fsl,imx8mm-ddr-pmu", .data = &imx8mm_devtype_data},
+ { .compatible = "fsl,imx8mn-ddr-pmu", .data = &imx8mn_devtype_data},
+ { .compatible = "fsl,imx8mp-ddr-pmu", .data = &imx8mp_devtype_data},
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx_ddr_pmu_dt_ids);
+
+struct ddr_pmu {
+ struct pmu pmu;
+ void __iomem *base;
+ unsigned int cpu;
+ struct hlist_node node;
+ struct device *dev;
+ struct perf_event *events[NUM_COUNTERS];
+ int active_events;
+ enum cpuhp_state cpuhp_state;
+ const struct fsl_ddr_devtype_data *devtype_data;
+ int irq;
+ int id;
+ int active_counter;
+};
+
+static ssize_t ddr_perf_identifier_show(struct device *dev,
+ struct device_attribute *attr,
+ char *page)
+{
+ struct ddr_pmu *pmu = dev_get_drvdata(dev);
+
+ return sysfs_emit(page, "%s\n", pmu->devtype_data->identifier);
+}
+
+static umode_t ddr_perf_identifier_attr_visible(struct kobject *kobj,
+ struct attribute *attr,
+ int n)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct ddr_pmu *pmu = dev_get_drvdata(dev);
+
+ if (!pmu->devtype_data->identifier)
+ return 0;
+ return attr->mode;
+};
+
+static struct device_attribute ddr_perf_identifier_attr =
+ __ATTR(identifier, 0444, ddr_perf_identifier_show, NULL);
+
+static struct attribute *ddr_perf_identifier_attrs[] = {
+ &ddr_perf_identifier_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group ddr_perf_identifier_attr_group = {
+ .attrs = ddr_perf_identifier_attrs,
+ .is_visible = ddr_perf_identifier_attr_visible,
+};
+
+enum ddr_perf_filter_capabilities {
+ PERF_CAP_AXI_ID_FILTER = 0,
+ PERF_CAP_AXI_ID_FILTER_ENHANCED,
+ PERF_CAP_AXI_ID_FEAT_MAX,
+};
+
+static u32 ddr_perf_filter_cap_get(struct ddr_pmu *pmu, int cap)
+{
+ u32 quirks = pmu->devtype_data->quirks;
+
+ switch (cap) {
+ case PERF_CAP_AXI_ID_FILTER:
+ return !!(quirks & DDR_CAP_AXI_ID_FILTER);
+ case PERF_CAP_AXI_ID_FILTER_ENHANCED:
+ quirks &= DDR_CAP_AXI_ID_FILTER_ENHANCED;
+ return quirks == DDR_CAP_AXI_ID_FILTER_ENHANCED;
+ default:
+ WARN(1, "unknown filter cap %d\n", cap);
+ }
+
+ return 0;
+}
+
+static ssize_t ddr_perf_filter_cap_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ddr_pmu *pmu = dev_get_drvdata(dev);
+ struct dev_ext_attribute *ea =
+ container_of(attr, struct dev_ext_attribute, attr);
+ int cap = (long)ea->var;
+
+ return sysfs_emit(buf, "%u\n", ddr_perf_filter_cap_get(pmu, cap));
+}
+
+#define PERF_EXT_ATTR_ENTRY(_name, _func, _var) \
+ (&((struct dev_ext_attribute) { \
+ __ATTR(_name, 0444, _func, NULL), (void *)_var \
+ }).attr.attr)
+
+#define PERF_FILTER_EXT_ATTR_ENTRY(_name, _var) \
+ PERF_EXT_ATTR_ENTRY(_name, ddr_perf_filter_cap_show, _var)
+
+static struct attribute *ddr_perf_filter_cap_attr[] = {
+ PERF_FILTER_EXT_ATTR_ENTRY(filter, PERF_CAP_AXI_ID_FILTER),
+ PERF_FILTER_EXT_ATTR_ENTRY(enhanced_filter, PERF_CAP_AXI_ID_FILTER_ENHANCED),
+ NULL,
+};
+
+static const struct attribute_group ddr_perf_filter_cap_attr_group = {
+ .name = "caps",
+ .attrs = ddr_perf_filter_cap_attr,
+};
+
+static ssize_t ddr_perf_cpumask_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ddr_pmu *pmu = dev_get_drvdata(dev);
+
+ return cpumap_print_to_pagebuf(true, buf, cpumask_of(pmu->cpu));
+}
+
+static struct device_attribute ddr_perf_cpumask_attr =
+ __ATTR(cpumask, 0444, ddr_perf_cpumask_show, NULL);
+
+static struct attribute *ddr_perf_cpumask_attrs[] = {
+ &ddr_perf_cpumask_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group ddr_perf_cpumask_attr_group = {
+ .attrs = ddr_perf_cpumask_attrs,
+};
+
+static ssize_t
+ddr_pmu_event_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 sysfs_emit(page, "event=0x%02llx\n", pmu_attr->id);
+}
+
+#define IMX8_DDR_PMU_EVENT_ATTR(_name, _id) \
+ PMU_EVENT_ATTR_ID(_name, ddr_pmu_event_show, _id)
+
+static struct attribute *ddr_perf_events_attrs[] = {
+ IMX8_DDR_PMU_EVENT_ATTR(cycles, EVENT_CYCLES_ID),
+ IMX8_DDR_PMU_EVENT_ATTR(selfresh, 0x01),
+ IMX8_DDR_PMU_EVENT_ATTR(read-accesses, 0x04),
+ IMX8_DDR_PMU_EVENT_ATTR(write-accesses, 0x05),
+ IMX8_DDR_PMU_EVENT_ATTR(read-queue-depth, 0x08),
+ IMX8_DDR_PMU_EVENT_ATTR(write-queue-depth, 0x09),
+ IMX8_DDR_PMU_EVENT_ATTR(lp-read-credit-cnt, 0x10),
+ IMX8_DDR_PMU_EVENT_ATTR(hp-read-credit-cnt, 0x11),
+ IMX8_DDR_PMU_EVENT_ATTR(write-credit-cnt, 0x12),
+ IMX8_DDR_PMU_EVENT_ATTR(read-command, 0x20),
+ IMX8_DDR_PMU_EVENT_ATTR(write-command, 0x21),
+ IMX8_DDR_PMU_EVENT_ATTR(read-modify-write-command, 0x22),
+ IMX8_DDR_PMU_EVENT_ATTR(hp-read, 0x23),
+ IMX8_DDR_PMU_EVENT_ATTR(hp-req-nocredit, 0x24),
+ IMX8_DDR_PMU_EVENT_ATTR(hp-xact-credit, 0x25),
+ IMX8_DDR_PMU_EVENT_ATTR(lp-req-nocredit, 0x26),
+ IMX8_DDR_PMU_EVENT_ATTR(lp-xact-credit, 0x27),
+ IMX8_DDR_PMU_EVENT_ATTR(wr-xact-credit, 0x29),
+ IMX8_DDR_PMU_EVENT_ATTR(read-cycles, 0x2a),
+ IMX8_DDR_PMU_EVENT_ATTR(write-cycles, 0x2b),
+ IMX8_DDR_PMU_EVENT_ATTR(read-write-transition, 0x30),
+ IMX8_DDR_PMU_EVENT_ATTR(precharge, 0x31),
+ IMX8_DDR_PMU_EVENT_ATTR(activate, 0x32),
+ IMX8_DDR_PMU_EVENT_ATTR(load-mode, 0x33),
+ IMX8_DDR_PMU_EVENT_ATTR(perf-mwr, 0x34),
+ IMX8_DDR_PMU_EVENT_ATTR(read, 0x35),
+ IMX8_DDR_PMU_EVENT_ATTR(read-activate, 0x36),
+ IMX8_DDR_PMU_EVENT_ATTR(refresh, 0x37),
+ IMX8_DDR_PMU_EVENT_ATTR(write, 0x38),
+ IMX8_DDR_PMU_EVENT_ATTR(raw-hazard, 0x39),
+ IMX8_DDR_PMU_EVENT_ATTR(axid-read, 0x41),
+ IMX8_DDR_PMU_EVENT_ATTR(axid-write, 0x42),
+ NULL,
+};
+
+static const struct attribute_group ddr_perf_events_attr_group = {
+ .name = "events",
+ .attrs = ddr_perf_events_attrs,
+};
+
+PMU_FORMAT_ATTR(event, "config:0-7");
+PMU_FORMAT_ATTR(axi_id, "config1:0-15");
+PMU_FORMAT_ATTR(axi_mask, "config1:16-31");
+
+static struct attribute *ddr_perf_format_attrs[] = {
+ &format_attr_event.attr,
+ &format_attr_axi_id.attr,
+ &format_attr_axi_mask.attr,
+ NULL,
+};
+
+static const struct attribute_group ddr_perf_format_attr_group = {
+ .name = "format",
+ .attrs = ddr_perf_format_attrs,
+};
+
+static const struct attribute_group *attr_groups[] = {
+ &ddr_perf_events_attr_group,
+ &ddr_perf_format_attr_group,
+ &ddr_perf_cpumask_attr_group,
+ &ddr_perf_filter_cap_attr_group,
+ &ddr_perf_identifier_attr_group,
+ NULL,
+};
+
+static bool ddr_perf_is_filtered(struct perf_event *event)
+{
+ return event->attr.config == 0x41 || event->attr.config == 0x42;
+}
+
+static u32 ddr_perf_filter_val(struct perf_event *event)
+{
+ return event->attr.config1;
+}
+
+static bool ddr_perf_filters_compatible(struct perf_event *a,
+ struct perf_event *b)
+{
+ if (!ddr_perf_is_filtered(a))
+ return true;
+ if (!ddr_perf_is_filtered(b))
+ return true;
+ return ddr_perf_filter_val(a) == ddr_perf_filter_val(b);
+}
+
+static bool ddr_perf_is_enhanced_filtered(struct perf_event *event)
+{
+ unsigned int filt;
+ struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
+
+ filt = pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER_ENHANCED;
+ return (filt == DDR_CAP_AXI_ID_FILTER_ENHANCED) &&
+ ddr_perf_is_filtered(event);
+}
+
+static u32 ddr_perf_alloc_counter(struct ddr_pmu *pmu, int event)
+{
+ int i;
+
+ /*
+ * Always map cycle event to counter 0
+ * Cycles counter is dedicated for cycle event
+ * can't used for the other events
+ */
+ if (event == EVENT_CYCLES_ID) {
+ if (pmu->events[EVENT_CYCLES_COUNTER] == NULL)
+ return EVENT_CYCLES_COUNTER;
+ else
+ return -ENOENT;
+ }
+
+ for (i = 1; i < NUM_COUNTERS; i++) {
+ if (pmu->events[i] == NULL)
+ return i;
+ }
+
+ return -ENOENT;
+}
+
+static void ddr_perf_free_counter(struct ddr_pmu *pmu, int counter)
+{
+ pmu->events[counter] = NULL;
+}
+
+static u32 ddr_perf_read_counter(struct ddr_pmu *pmu, int counter)
+{
+ struct perf_event *event = pmu->events[counter];
+ void __iomem *base = pmu->base;
+
+ /*
+ * return bytes instead of bursts from ddr transaction for
+ * axid-read and axid-write event if PMU core supports enhanced
+ * filter.
+ */
+ base += ddr_perf_is_enhanced_filtered(event) ? COUNTER_DPCR1 :
+ COUNTER_READ;
+ return readl_relaxed(base + counter * 4);
+}
+
+static int ddr_perf_event_init(struct perf_event *event)
+{
+ struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ struct perf_event *sibling;
+
+ if (event->attr.type != event->pmu->type)
+ return -ENOENT;
+
+ if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
+ return -EOPNOTSUPP;
+
+ if (event->cpu < 0) {
+ dev_warn(pmu->dev, "Can't provide per-task data!\n");
+ return -EOPNOTSUPP;
+ }
+
+ /*
+ * We must NOT create groups containing mixed PMUs, although software
+ * events are acceptable (for example to create a CCN group
+ * periodically read when a hrtimer aka cpu-clock leader triggers).
+ */
+ if (event->group_leader->pmu != event->pmu &&
+ !is_software_event(event->group_leader))
+ return -EINVAL;
+
+ if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER) {
+ if (!ddr_perf_filters_compatible(event, event->group_leader))
+ return -EINVAL;
+ for_each_sibling_event(sibling, event->group_leader) {
+ if (!ddr_perf_filters_compatible(event, sibling))
+ return -EINVAL;
+ }
+ }
+
+ for_each_sibling_event(sibling, event->group_leader) {
+ if (sibling->pmu != event->pmu &&
+ !is_software_event(sibling))
+ return -EINVAL;
+ }
+
+ event->cpu = pmu->cpu;
+ hwc->idx = -1;
+
+ return 0;
+}
+
+static void ddr_perf_counter_enable(struct ddr_pmu *pmu, int config,
+ int counter, bool enable)
+{
+ u8 reg = counter * 4 + COUNTER_CNTL;
+ int val;
+
+ if (enable) {
+ /*
+ * cycle counter is special which should firstly write 0 then
+ * write 1 into CLEAR bit to clear it. Other counters only
+ * need write 0 into CLEAR bit and it turns out to be 1 by
+ * hardware. Below enable flow is harmless for all counters.
+ */
+ writel(0, pmu->base + reg);
+ val = CNTL_EN | CNTL_CLEAR;
+ val |= FIELD_PREP(CNTL_CSV_MASK, config);
+
+ /*
+ * On i.MX8MP we need to bias the cycle counter to overflow more often.
+ * We do this by initializing bits [23:16] of the counter value via the
+ * COUNTER_CTRL Counter Parameter (CP) field.
+ */
+ if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER_ENHANCED) {
+ if (counter == EVENT_CYCLES_COUNTER)
+ val |= FIELD_PREP(CNTL_CP_MASK, 0xf0);
+ }
+
+ writel(val, pmu->base + reg);
+ } else {
+ /* Disable counter */
+ val = readl_relaxed(pmu->base + reg) & CNTL_EN_MASK;
+ writel(val, pmu->base + reg);
+ }
+}
+
+static bool ddr_perf_counter_overflow(struct ddr_pmu *pmu, int counter)
+{
+ int val;
+
+ val = readl_relaxed(pmu->base + counter * 4 + COUNTER_CNTL);
+
+ return val & CNTL_OVER;
+}
+
+static void ddr_perf_counter_clear(struct ddr_pmu *pmu, int counter)
+{
+ u8 reg = counter * 4 + COUNTER_CNTL;
+ int val;
+
+ val = readl_relaxed(pmu->base + reg);
+ val &= ~CNTL_CLEAR;
+ writel(val, pmu->base + reg);
+
+ val |= CNTL_CLEAR;
+ writel(val, pmu->base + reg);
+}
+
+static void ddr_perf_event_update(struct perf_event *event)
+{
+ struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ u64 new_raw_count;
+ int counter = hwc->idx;
+ int ret;
+
+ new_raw_count = ddr_perf_read_counter(pmu, counter);
+ /* Remove the bias applied in ddr_perf_counter_enable(). */
+ if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER_ENHANCED) {
+ if (counter == EVENT_CYCLES_COUNTER)
+ new_raw_count &= CYCLES_COUNTER_MASK;
+ }
+
+ local64_add(new_raw_count, &event->count);
+
+ /*
+ * For legacy SoCs: event counter continue counting when overflow,
+ * no need to clear the counter.
+ * For new SoCs: event counter stop counting when overflow, need
+ * clear counter to let it count again.
+ */
+ if (counter != EVENT_CYCLES_COUNTER) {
+ ret = ddr_perf_counter_overflow(pmu, counter);
+ if (ret)
+ dev_warn_ratelimited(pmu->dev, "events lost due to counter overflow (config 0x%llx)\n",
+ event->attr.config);
+ }
+
+ /* clear counter every time for both cycle counter and event counter */
+ ddr_perf_counter_clear(pmu, counter);
+}
+
+static void ddr_perf_event_start(struct perf_event *event, int flags)
+{
+ struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ int counter = hwc->idx;
+
+ local64_set(&hwc->prev_count, 0);
+
+ ddr_perf_counter_enable(pmu, event->attr.config, counter, true);
+
+ if (!pmu->active_counter++)
+ ddr_perf_counter_enable(pmu, EVENT_CYCLES_ID,
+ EVENT_CYCLES_COUNTER, true);
+
+ hwc->state = 0;
+}
+
+static int ddr_perf_event_add(struct perf_event *event, int flags)
+{
+ struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ int counter;
+ int cfg = event->attr.config;
+ int cfg1 = event->attr.config1;
+
+ if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER) {
+ int i;
+
+ for (i = 1; i < NUM_COUNTERS; i++) {
+ if (pmu->events[i] &&
+ !ddr_perf_filters_compatible(event, pmu->events[i]))
+ return -EINVAL;
+ }
+
+ if (ddr_perf_is_filtered(event)) {
+ /* revert axi id masking(axi_mask) value */
+ cfg1 ^= AXI_MASKING_REVERT;
+ writel(cfg1, pmu->base + COUNTER_DPCR1);
+ }
+ }
+
+ counter = ddr_perf_alloc_counter(pmu, cfg);
+ if (counter < 0) {
+ dev_dbg(pmu->dev, "There are not enough counters\n");
+ return -EOPNOTSUPP;
+ }
+
+ pmu->events[counter] = event;
+ pmu->active_events++;
+ hwc->idx = counter;
+
+ hwc->state |= PERF_HES_STOPPED;
+
+ if (flags & PERF_EF_START)
+ ddr_perf_event_start(event, flags);
+
+ return 0;
+}
+
+static void ddr_perf_event_stop(struct perf_event *event, int flags)
+{
+ struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ int counter = hwc->idx;
+
+ ddr_perf_counter_enable(pmu, event->attr.config, counter, false);
+ ddr_perf_event_update(event);
+
+ if (!--pmu->active_counter)
+ ddr_perf_counter_enable(pmu, EVENT_CYCLES_ID,
+ EVENT_CYCLES_COUNTER, false);
+
+ hwc->state |= PERF_HES_STOPPED;
+}
+
+static void ddr_perf_event_del(struct perf_event *event, int flags)
+{
+ struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ int counter = hwc->idx;
+
+ ddr_perf_event_stop(event, PERF_EF_UPDATE);
+
+ ddr_perf_free_counter(pmu, counter);
+ pmu->active_events--;
+ hwc->idx = -1;
+}
+
+static void ddr_perf_pmu_enable(struct pmu *pmu)
+{
+}
+
+static void ddr_perf_pmu_disable(struct pmu *pmu)
+{
+}
+
+static int ddr_perf_init(struct ddr_pmu *pmu, void __iomem *base,
+ struct device *dev)
+{
+ *pmu = (struct ddr_pmu) {
+ .pmu = (struct pmu) {
+ .module = THIS_MODULE,
+ .capabilities = PERF_PMU_CAP_NO_EXCLUDE,
+ .task_ctx_nr = perf_invalid_context,
+ .attr_groups = attr_groups,
+ .event_init = ddr_perf_event_init,
+ .add = ddr_perf_event_add,
+ .del = ddr_perf_event_del,
+ .start = ddr_perf_event_start,
+ .stop = ddr_perf_event_stop,
+ .read = ddr_perf_event_update,
+ .pmu_enable = ddr_perf_pmu_enable,
+ .pmu_disable = ddr_perf_pmu_disable,
+ },
+ .base = base,
+ .dev = dev,
+ };
+
+ pmu->id = ida_alloc(&ddr_ida, GFP_KERNEL);
+ return pmu->id;
+}
+
+static irqreturn_t ddr_perf_irq_handler(int irq, void *p)
+{
+ int i;
+ struct ddr_pmu *pmu = (struct ddr_pmu *) p;
+ struct perf_event *event;
+
+ /* all counter will stop if cycle counter disabled */
+ ddr_perf_counter_enable(pmu,
+ EVENT_CYCLES_ID,
+ EVENT_CYCLES_COUNTER,
+ false);
+ /*
+ * When the cycle counter overflows, all counters are stopped,
+ * and an IRQ is raised. If any other counter overflows, it
+ * continues counting, and no IRQ is raised. But for new SoCs,
+ * such as i.MX8MP, event counter would stop when overflow, so
+ * we need use cycle counter to stop overflow of event counter.
+ *
+ * Cycles occur at least 4 times as often as other events, so we
+ * can update all events on a cycle counter overflow and not
+ * lose events.
+ *
+ */
+ for (i = 0; i < NUM_COUNTERS; i++) {
+
+ if (!pmu->events[i])
+ continue;
+
+ event = pmu->events[i];
+
+ ddr_perf_event_update(event);
+ }
+
+ ddr_perf_counter_enable(pmu,
+ EVENT_CYCLES_ID,
+ EVENT_CYCLES_COUNTER,
+ true);
+
+ return IRQ_HANDLED;
+}
+
+static int ddr_perf_offline_cpu(unsigned int cpu, struct hlist_node *node)
+{
+ struct ddr_pmu *pmu = hlist_entry_safe(node, struct ddr_pmu, node);
+ int target;
+
+ if (cpu != pmu->cpu)
+ return 0;
+
+ target = cpumask_any_but(cpu_online_mask, cpu);
+ if (target >= nr_cpu_ids)
+ return 0;
+
+ perf_pmu_migrate_context(&pmu->pmu, cpu, target);
+ pmu->cpu = target;
+
+ WARN_ON(irq_set_affinity(pmu->irq, cpumask_of(pmu->cpu)));
+
+ return 0;
+}
+
+static int ddr_perf_probe(struct platform_device *pdev)
+{
+ struct ddr_pmu *pmu;
+ struct device_node *np;
+ void __iomem *base;
+ char *name;
+ int num;
+ int ret;
+ int irq;
+
+ base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ np = pdev->dev.of_node;
+
+ pmu = devm_kzalloc(&pdev->dev, sizeof(*pmu), GFP_KERNEL);
+ if (!pmu)
+ return -ENOMEM;
+
+ num = ddr_perf_init(pmu, base, &pdev->dev);
+
+ platform_set_drvdata(pdev, pmu);
+
+ name = devm_kasprintf(&pdev->dev, GFP_KERNEL, DDR_PERF_DEV_NAME "%d",
+ num);
+ if (!name) {
+ ret = -ENOMEM;
+ goto cpuhp_state_err;
+ }
+
+ pmu->devtype_data = of_device_get_match_data(&pdev->dev);
+
+ pmu->cpu = raw_smp_processor_id();
+ ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
+ DDR_CPUHP_CB_NAME,
+ NULL,
+ ddr_perf_offline_cpu);
+
+ if (ret < 0) {
+ dev_err(&pdev->dev, "cpuhp_setup_state_multi failed\n");
+ goto cpuhp_state_err;
+ }
+
+ pmu->cpuhp_state = ret;
+
+ /* Register the pmu instance for cpu hotplug */
+ ret = cpuhp_state_add_instance_nocalls(pmu->cpuhp_state, &pmu->node);
+ if (ret) {
+ dev_err(&pdev->dev, "Error %d registering hotplug\n", ret);
+ goto cpuhp_instance_err;
+ }
+
+ /* Request irq */
+ irq = of_irq_get(np, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "Failed to get irq: %d", irq);
+ ret = irq;
+ goto ddr_perf_err;
+ }
+
+ ret = devm_request_irq(&pdev->dev, irq,
+ ddr_perf_irq_handler,
+ IRQF_NOBALANCING | IRQF_NO_THREAD,
+ DDR_CPUHP_CB_NAME,
+ pmu);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Request irq failed: %d", ret);
+ goto ddr_perf_err;
+ }
+
+ pmu->irq = irq;
+ ret = irq_set_affinity(pmu->irq, cpumask_of(pmu->cpu));
+ if (ret) {
+ dev_err(pmu->dev, "Failed to set interrupt affinity!\n");
+ goto ddr_perf_err;
+ }
+
+ ret = perf_pmu_register(&pmu->pmu, name, -1);
+ if (ret)
+ goto ddr_perf_err;
+
+ return 0;
+
+ddr_perf_err:
+ cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
+cpuhp_instance_err:
+ cpuhp_remove_multi_state(pmu->cpuhp_state);
+cpuhp_state_err:
+ ida_free(&ddr_ida, pmu->id);
+ dev_warn(&pdev->dev, "i.MX8 DDR Perf PMU failed (%d), disabled\n", ret);
+ return ret;
+}
+
+static int ddr_perf_remove(struct platform_device *pdev)
+{
+ struct ddr_pmu *pmu = platform_get_drvdata(pdev);
+
+ cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
+ cpuhp_remove_multi_state(pmu->cpuhp_state);
+
+ perf_pmu_unregister(&pmu->pmu);
+
+ ida_free(&ddr_ida, pmu->id);
+ return 0;
+}
+
+static struct platform_driver imx_ddr_pmu_driver = {
+ .driver = {
+ .name = "imx-ddr-pmu",
+ .of_match_table = imx_ddr_pmu_dt_ids,
+ .suppress_bind_attrs = true,
+ },
+ .probe = ddr_perf_probe,
+ .remove = ddr_perf_remove,
+};
+
+module_platform_driver(imx_ddr_pmu_driver);
+MODULE_LICENSE("GPL v2");