> -----Original Message-----
> From: Xu Yang
> Sent: Tuesday, April 18, 2023 6:27 PM
> To: will@xxxxxxxxxx; mark.rutland@xxxxxxx; shawnguo@xxxxxxxxxx; Frank Li <frank.li@xxxxxxx>; festevam@xxxxxxxxx
> Cc: robh+dt@xxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; dl-linux-imx <linux-
> imx@xxxxxxx>
> Subject: [PATCH v2 1/3] drivers/perf: imx_ddr: Add support for NXP i.MX9 SoC DDRC PMU driver
>
> Add ddr performance monitor support for i.MX93.
>
> There are 11 counters for ddr performance events.
> - Counter 0 is a 64-bit counter that counts only clock cycles.
> - Counter 1-10 are 32-bit counters that can monitor counter-specific
> events in addition to counting reference events.
>
> For example:
> perf stat -a -e imx9_ddr0/ddrc_pm_1,counter=1/,imx9_ddr0/ddrc_pm_2,counter=2/ ls
>
> Besides, this ddr pmu support AXI filter capability. It's implemented as
> counter-specific events. It now supports read transaction, write transaction
> and read beat events which corresponding respecitively to counter 2, 3 and 4.
> axi_mask and axi_id need to be as event parameters.
>
> For example:
> perf stat -a -I 1000 -e imx9_ddr0/eddrtq_pm_rd_trans_filt,counter=2,axi_mask=ID_MASK,axi_id=ID/
> perf stat -a -I 1000 -e imx9_ddr0/eddrtq_pm_wr_trans_filt,counter=3,axi_mask=ID_MASK,axi_id=ID/
> perf stat -a -I 1000 -e imx9_ddr0/eddrtq_pm_rd_beat_filt,counter=4,axi_mask=ID_MASK,axi_id=ID/
>
> Signed-off-by: Xu Yang <xu.yang_2@xxxxxxx>
>
> ---
> Changes from v2:
> - optimize cycles counter reading logic according to frank's suggestion
>
> diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig
> index 66c259000a44..8e95ec362a18 100644
> --- a/drivers/perf/Kconfig
> +++ b/drivers/perf/Kconfig
> @@ -117,6 +117,14 @@ config FSL_IMX8_DDR_PMU
> can give information about memory throughput and other related
> events.
>
> +config FSL_IMX9_DDR_PMU
> + tristate "Freescale i.MX9 DDR perf monitor"
> + depends on ARCH_MXC
> + help
> + Provides support for the DDR performance monitor in i.MX9, which
> + can give information about memory throughput and other related
> + events.
> +
> config QCOM_L2_PMU
> bool "Qualcomm Technologies L2-cache PMU"
> depends on ARCH_QCOM && ARM64 && ACPI
> diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile
> index 13e45da61100..d37cb217d528 100644
> --- a/drivers/perf/Makefile
> +++ b/drivers/perf/Makefile
> @@ -7,6 +7,7 @@ obj-$(CONFIG_ARM_PMU) += arm_pmu.o arm_pmu_platform.o
> obj-$(CONFIG_ARM_PMU_ACPI) += arm_pmu_acpi.o
> obj-$(CONFIG_ARM_SMMU_V3_PMU) += arm_smmuv3_pmu.o
> obj-$(CONFIG_FSL_IMX8_DDR_PMU) += fsl_imx8_ddr_perf.o
> +obj-$(CONFIG_FSL_IMX9_DDR_PMU) += fsl_imx9_ddr_perf.o
> obj-$(CONFIG_HISI_PMU) += hisilicon/
> obj-$(CONFIG_QCOM_L2_PMU) += qcom_l2_pmu.o
> obj-$(CONFIG_QCOM_L3_PMU) += qcom_l3_pmu.o
> diff --git a/drivers/perf/fsl_imx9_ddr_perf.c b/drivers/perf/fsl_imx9_ddr_perf.c
> new file mode 100644
> index 000000000000..06754d238007
> --- /dev/null
> +++ b/drivers/perf/fsl_imx9_ddr_perf.c
> @@ -0,0 +1,712 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright 2023 NXP
> +
> +#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>
> +
> +/* Performance monitor configuration */
> +#define PMCFG1 0x00
> +#define PMCFG1_RD_TRANS_FILT_EN BIT(31)
> +#define PMCFG1_WR_TRANS_FILT_EN BIT(30)
> +#define PMCFG1_RD_BT_FILT_EN BIT(29)
> +#define PMCFG1_ID_MASK GENMASK(17, 0)
> +
> +#define PMCFG2 0x04
> +#define PMCFG2_ID GENMASK(17, 0)
> +
> +/* Global control register affects all counters and takes priority over local control registers */
> +#define PMGC0 0x40
> +/* Global control register bits */
> +#define PMGC0_FAC BIT(31)
> +#define PMGC0_PMIE BIT(30)
> +#define PMGC0_FCECE BIT(29)
> +
> +/*
> + * 64bit counter0 exclusively dedicated to counting cycles
> + * 32bit counters monitor counter-specific events in addition to counting reference events
> + */
> +#define PMLCA(n) (0x40 + 0x10 + (0x10 * n))
> +#define PMLCB(n) (0x40 + 0x14 + (0x10 * n))
> +#define PMC(n) (0x40 + 0x18 + (0x10 * n))
> +/* Local control register bits */
> +#define PMLCA_FC BIT(31)
> +#define PMLCA_CE BIT(26)
> +#define PMLCA_EVENT GENMASK(22, 16)
> +
> +#define NUM_COUNTERS 11
> +#define CYCLES_COUNTER 0
> +
> +#define to_ddr_pmu(p) container_of(p, struct ddr_pmu, pmu)
> +
> +#define DDR_PERF_DEV_NAME "imx9_ddr"
> +#define DDR_CPUHP_CB_NAME DDR_PERF_DEV_NAME "_perf_pmu"
> +
> +static DEFINE_IDA(ddr_ida);
> +
> +struct imx_ddr_devtype_data {
> + const char *identifier; /* system PMU identifier for userspace */
> +};
> +
> +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 imx_ddr_devtype_data *devtype_data;
> + int irq;
> + int id;
> +};
> +
> +static const struct imx_ddr_devtype_data imx93_devtype_data = {
> + .identifier = "imx93",
> +};
> +
> +static const struct of_device_id imx_ddr_pmu_dt_ids[] = {
> + {.compatible = "fsl,imx93-ddr-pmu", .data = &imx93_devtype_data},
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, imx_ddr_pmu_dt_ids);
> +
> +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 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 struct attribute_group ddr_perf_identifier_attr_group = {
> + .attrs = ddr_perf_identifier_attrs,
> +};
> +
> +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 IMX9_DDR_PMU_EVENT_ATTR(_name, _id) \
> + (&((struct perf_pmu_events_attr[]) { \
> + { .attr = __ATTR(_name, 0444, ddr_pmu_event_show, NULL),\
> + .id = _id, } \
> + })[0].attr.attr)
> +
> +static struct attribute *ddr_perf_events_attrs[] = {
> + /* counter0 cycles event */
> + IMX9_DDR_PMU_EVENT_ATTR(cycles, 0),
> +
> + /* reference events for all normal counters, need assert DEBUG19[21] bit */
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ddrc1_rmw_for_ecc, 12),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_rreorder, 13),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_wreorder, 14),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_0, 15),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_1, 16),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_2, 17),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_3, 18),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_4, 19),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_5, 22),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_6, 23),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_7, 24),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_8, 25),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_9, 26),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_10, 27),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_11, 28),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_12, 31),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_13, 59),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_15, 61),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_pm_29, 63),
> +
> + /* counter1 specific events */
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_riq_0, 64),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_riq_1, 65),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_riq_2, 66),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_riq_3, 67),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_riq_4, 68),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_riq_5, 69),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_riq_6, 70),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_riq_7, 71),
> +
> + /* counter2 specific events */
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_wiq_0, 64),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_wiq_1, 65),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_wiq_2, 66),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_wiq_3, 67),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_wiq_4, 68),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_wiq_5, 69),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_wiq_6, 70),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_ld_wiq_7, 71),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_empty, 72),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pm_rd_trans_filt, 73),
> +
> + /* counter3 specific events */
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_collision_0, 64),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_collision_1, 65),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_collision_2, 66),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_collision_3, 67),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_collision_4, 68),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_collision_5, 69),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_collision_6, 70),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_collision_7, 71),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_full, 72),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pm_wr_trans_filt, 73),
> +
> + /* counter4 specific events */
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_open_0, 64),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_open_1, 65),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_open_2, 66),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_open_3, 67),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_open_4, 68),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_open_5, 69),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_open_6, 70),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_row_open_7, 71),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_ld_rdq2_rmw, 72),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pm_rd_beat_filt, 73),
> +
> + /* counter5 specific events */
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_valid_start_0, 64),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_valid_start_1, 65),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_valid_start_2, 66),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_valid_start_3, 67),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_valid_start_4, 68),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_valid_start_5, 69),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_valid_start_6, 70),
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_valid_start_7, 71),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_ld_rdq1, 72),
> +
> + /* counter6 specific events */
> + IMX9_DDR_PMU_EVENT_ATTR(ddrc_qx_valid_end_0, 64),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_ld_rdq2, 72),
> +
> + /* counter7 specific events */
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_1_2_full, 64),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_ld_wrq0, 65),
> +
> + /* counter8 specific events */
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_bias_switched, 64),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_1_4_full, 65),
> +
> + /* counter9 specific events */
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_ld_wrq1, 65),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_3_4_full, 66),
> +
> + /* counter10 specific events */
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_misc_mrk, 65),
> + IMX9_DDR_PMU_EVENT_ATTR(eddrtq_pmon_ld_rdq0, 66),
> + 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(counter, "config:8-15");
> +PMU_FORMAT_ATTR(axi_id, "config1:0-17");
> +PMU_FORMAT_ATTR(axi_mask, "config2:0-17");
> +
> +static struct attribute *ddr_perf_format_attrs[] = {
> + &format_attr_event.attr,
> + &format_attr_counter.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_identifier_attr_group,
> + &ddr_perf_cpumask_attr_group,
> + &ddr_perf_events_attr_group,
> + &ddr_perf_format_attr_group,
> + NULL,
> +};
> +
> +static void ddr_perf_clear_counter(struct ddr_pmu *pmu, int counter)
> +{
> + if (counter == CYCLES_COUNTER) {
> + writel(0, pmu->base + PMC(counter) + 0x4);
> + writel(0, pmu->base + PMC(counter));
> + } else {
> + writel(0, pmu->base + PMC(counter));
> + }
> +}
> +
> +static u64 ddr_perf_read_counter(struct ddr_pmu *pmu, int counter)
> +{
> + u32 val_lower, val_upper;
> + u64 val;
> +
> + if (counter != CYCLES_COUNTER) {
> + val = readl_relaxed(pmu->base + PMC(counter));
> + goto out;
> + }
> +
> + /* special handling for reading 64bit cycle counter */
> + do {
> + val_upper = readl_relaxed(pmu->base + PMC(counter) + 0x4);
> + val_lower = readl_relaxed(pmu->base + PMC(counter));
> + } while (val_upper != readl_relaxed(pmu->base + PMC(counter) + 0x4));
> +
> + val = val_upper;
> + val = (val << 32);
> + val |= val_lower;
> +out:
> + return val;
> +}
> +
> +static void ddr_perf_counter_global_config(struct ddr_pmu *pmu, bool enable)
> +{
> + u32 ctrl;
> +
> + ctrl = readl_relaxed(pmu->base + PMGC0);
> +
> + if (enable) {
> + /*
> + * The performance monitor must be reset before event counting
> + * sequences. The performance monitor can be reset by first freezing
> + * one or more counters and then clearing the freeze condition to
> + * allow the counters to count according to the settings in the
> + * performance monitor registers. Counters can be frozen individually
> + * by setting PMLCAn[FC] bits, or simultaneously by setting PMGC0[FAC].
> + * Simply clearing these freeze bits will then allow the performance
> + * monitor to begin counting based on the register settings.
> + */
> + ctrl |= PMGC0_FAC;
> + writel(ctrl, pmu->base + PMGC0);
> +
> + /*
> + * Freeze all counters disabled, interrupt enabled, and freeze
> + * counters on condition enabled.
> + */
> + ctrl &= ~PMGC0_FAC;
> + ctrl |= PMGC0_PMIE | PMGC0_FCECE;
> + writel(ctrl, pmu->base + PMGC0);
> + } else {
> + ctrl |= PMGC0_FAC;
> + ctrl &= ~(PMGC0_PMIE | PMGC0_FCECE);
> + writel(ctrl, pmu->base + PMGC0);
> + }
> +}
> +
> +static void ddr_perf_counter_local_config(struct ddr_pmu *pmu, int config,
> + int counter, bool enable)
> +{
> + u32 ctrl_a;
> +
> + ctrl_a = readl_relaxed(pmu->base + PMLCA(counter));
> +
> + if (enable) {
> + ctrl_a |= PMLCA_FC;
> + writel(ctrl_a, pmu->base + PMLCA(counter));
> +
> + ddr_perf_clear_counter(pmu, counter);
> +
> + /* Freeze counter disabled, condition enabled, and program event.*/
> + ctrl_a &= ~PMLCA_FC;
> + ctrl_a |= PMLCA_CE;
> + ctrl_a &= ~FIELD_PREP(PMLCA_EVENT, 0x7F);
> + ctrl_a |= FIELD_PREP(PMLCA_EVENT, (config & 0x000000FF));
> + writel(ctrl_a, pmu->base + PMLCA(counter));
> + } else {
> + /* Freeze counter. */
> + ctrl_a |= PMLCA_FC;
> + writel(ctrl_a, pmu->base + PMLCA(counter));
> + }
> +}
> +
> +static void ddr_perf_monitor_config(struct ddr_pmu *pmu, int cfg, int cfg1, int cfg2)
> +{
> + u32 pmcfg1, pmcfg2;
> + int event, counter;
> +
> + event = cfg & 0x000000FF;
> + counter = (cfg & 0x0000FF00) >> 8;
> +
> + pmcfg1 = readl_relaxed(pmu->base + PMCFG1);
> +
> + if (counter == 2 && event == 73)
> + pmcfg1 |= PMCFG1_RD_TRANS_FILT_EN;
> + else if (counter == 2 && event != 73)
> + pmcfg1 &= ~PMCFG1_RD_TRANS_FILT_EN;
> +
> + if (counter == 3 && event == 73)
> + pmcfg1 |= PMCFG1_WR_TRANS_FILT_EN;
> + else if (counter == 3 && event != 73)
> + pmcfg1 &= ~PMCFG1_WR_TRANS_FILT_EN;
> +
> + if (counter == 4 && event == 73)
> + pmcfg1 |= PMCFG1_RD_BT_FILT_EN;
> + else if (counter == 4 && event != 73)
> + pmcfg1 &= ~PMCFG1_RD_BT_FILT_EN;
> +
> + pmcfg1 &= ~FIELD_PREP(PMCFG1_ID_MASK, 0x3FFFF);
> + pmcfg1 |= FIELD_PREP(PMCFG1_ID_MASK, cfg2);
> + writel(pmcfg1, pmu->base + PMCFG1);
> +
> + pmcfg2 = readl_relaxed(pmu->base + PMCFG2);
> + pmcfg2 &= ~FIELD_PREP(PMCFG2_ID, 0x3FFFF);
> + pmcfg2 |= FIELD_PREP(PMCFG2_ID, cfg1);
> + writel(pmcfg2, pmu->base + PMCFG2);
> +}
> +
> +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;
> + int counter = hwc->idx;
> + u64 new_raw_count;
> +
> + new_raw_count = ddr_perf_read_counter(pmu, counter);
> + local64_add(new_raw_count, &event->count);
> +
> + /* clear counter's value every time */
> + ddr_perf_clear_counter(pmu, counter);
> +}
> +
> +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;
> +
> + 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_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_local_config(pmu, event->attr.config, 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 cfg = event->attr.config;
> + int cfg1 = event->attr.config1;
> + int cfg2 = event->attr.config2;
> + int counter;
> +
> + counter = (cfg & 0x0000FF00) >> 8;
> +
> + 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);
> +
> + /* read trans, write trans, read beat */
> + ddr_perf_monitor_config(pmu, cfg, cfg1, cfg2);
> +
> + 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_local_config(pmu, event->attr.config, counter, false);
> + ddr_perf_event_update(event);
> +
> + 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;
> +
> + ddr_perf_event_stop(event, PERF_EF_UPDATE);
> +
> + pmu->active_events--;
> + hwc->idx = -1;
> +}
> +
> +static void ddr_perf_pmu_enable(struct pmu *pmu)
> +{
> + struct ddr_pmu *ddr_pmu = to_ddr_pmu(pmu);
> +
> + ddr_perf_counter_global_config(ddr_pmu, true);
> +}
> +
> +static void ddr_perf_pmu_disable(struct pmu *pmu)
> +{
> + struct ddr_pmu *ddr_pmu = to_ddr_pmu(pmu);
> +
> + ddr_perf_counter_global_config(ddr_pmu, false);
> +}
> +
> +static void 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,
> + };
> +}
> +
> +static irqreturn_t ddr_perf_irq_handler(int irq, void *p)
> +{
> + struct ddr_pmu *pmu = (struct ddr_pmu *)p;
> + struct perf_event *event;
> + int i;
> +
> + /*
> + * Counters can generate an interrupt on an overflow when msb of a
> + * counter changes from 0 to 1. For the interrupt to be signalled,
> + * below condition mush be satisfied:
> + * PMGC0[PMIE] = 1, PMGC0[FCECE] = 1, PMLCAn[CE] = 1
> + * When an interrupt is signalled, PMGC0[FAC] is set by hardware and
> + * all of the registers are frozen.
> + * Software can clear the interrupt condition by resetting the performance
> + * monitor and clearing the most significant bit of the counter that
> + * generate the overflow.
> + */
> + for (i = 0; i < NUM_COUNTERS; i++) {
> + if (!pmu->events[i])
> + continue;
> +
> + event = pmu->events[i];
> +
> + ddr_perf_event_update(event);
> + }
> +
> + ddr_perf_counter_global_config(pmu, 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;
> + void __iomem *base;
> + int ret, irq;
> + char *name;
> +
> + base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(base))
> + return PTR_ERR(base);
> +
> + pmu = devm_kzalloc(&pdev->dev, sizeof(*pmu), GFP_KERNEL);
> + if (!pmu)
> + return -ENOMEM;
> +
> + ddr_perf_init(pmu, base, &pdev->dev);
> +
> + pmu->devtype_data = of_device_get_match_data(&pdev->dev);
> +
> + platform_set_drvdata(pdev, pmu);
> +
> + pmu->id = ida_simple_get(&ddr_ida, 0, 0, GFP_KERNEL);
> + name = devm_kasprintf(&pdev->dev, GFP_KERNEL, DDR_PERF_DEV_NAME "%d", pmu->id);
> + if (!name) {
> + ret = -ENOMEM;
> + goto format_string_err;
> + }
> +
> + 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, "Failed to add callbacks for multi state\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 = platform_get_irq(pdev, 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:
> +format_string_err:
> + ida_simple_remove(&ddr_ida, pmu->id);
> + dev_warn(&pdev->dev, "i.MX9 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_simple_remove(&ddr_ida, pmu->id);
> +
> + return 0;
> +}
> +
> +static struct platform_driver imx_ddr_pmu_driver = {
> + .driver = {
> + .name = "imx9-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_AUTHOR("Xu Yang <xu.yang_2@xxxxxxx>");
> +MODULE_LICENSE("GPL v2");
> +MODULE_DESCRIPTION("DDRC PerfMon for i.MX9 SoCs");
> --
> 2.34.1
A gentle ping.
Thanks
