On Fri, Feb 22, 2019 at 1:45 PM Zhi Li <lznuaa@xxxxxxxxx> wrote:
>
> On Fri, Feb 15, 2019 at 12:03 PM Frank Li <frank.li@xxxxxxx> wrote:
> >
> > Add ddr performance monitor support for iMX8QXP
> >
> > There are 4 counters for ddr perfomance events.
> > counter 0 is dedicated for cycles.
> > you choose any up to 3 no cycles events.
>
> Any additional comments for these patches?
Mark:
There are no comments for two weeks.
Did you plan pick up these patches?
best regards
Frank Li
>
> best regards
> Frank Li
>
> >
> > for example:
> >
> > perf stat -a -e ddr0/read-access/,ddr0/write-access/,ddr0/precharge/ ls
> > perf stat -a -e ddr0/cycles/,ddr0/read-access/,ddr0/write-access/ ls
> >
> > Support below events.
> >
> > ddr0/activate/ [Kernel PMU event]
> > ddr0/axid-read/ [Kernel PMU event]
> > ddr0/axid-write/ [Kernel PMU event]
> > ddr0/cycles/ [Kernel PMU event]
> > ddr0/hp-read-credit-cnt/ [Kernel PMU event]
> > ddr0/hp-read/ [Kernel PMU event]
> > ddr0/hp-req-nodcredit/ [Kernel PMU event]
> > ddr0/hp-xact-credit/ [Kernel PMU event]
> > ddr0/load-mode/ [Kernel PMU event]
> > ddr0/lp-read-credit-cnt/ [Kernel PMU event]
> > ddr0/lp-req-nocredit/ [Kernel PMU event]
> > ddr0/lp-xact-credit/ [Kernel PMU event]
> > ddr0/mwr/ [Kernel PMU event]
> > ddr0/precharge/ [Kernel PMU event]
> > ddr0/raw-hazard/ [Kernel PMU event]
> > ddr0/read-access/ [Kernel PMU event]
> > ddr0/read-activate/ [Kernel PMU event]
> > ddr0/read-command/ [Kernel PMU event]
> > ddr0/read-cycles/ [Kernel PMU event]
> > ddr0/read-modify-write-command/ [Kernel PMU event]
> > ddr0/read-queue-depth/ [Kernel PMU event]
> > ddr0/read-write-transition/ [Kernel PMU event]
> > ddr0/read/ [Kernel PMU event]
> > ddr0/refresh/ [Kernel PMU event]
> > ddr0/selfresh/ [Kernel PMU event]
> > ddr0/wr-xact-credit/ [Kernel PMU event]
> > ddr0/write-access/ [Kernel PMU event]
> > ddr0/write-command/ [Kernel PMU event]
> > ddr0/write-credit-cnt/ [Kernel PMU event]
> > ddr0/write-cycles/ [Kernel PMU event]
> > ddr0/write-queue-depth/ [Kernel PMU event]
> > ddr0/write/
> >
> > Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
> > ---
> > Change from v3 to v4
> > * Change FSL_IMX8_DDR_PERF to FSL_IMX8_DDR_PMU
> > * sort include
> > * remove struct fsl_ddr_devtype_data
> > * Added comment need disable control first
> > * Added comment about must enable cycle counter
> > * Added macro for EVENT_AXI_READ, remove hardcode 0x41 and 0x42
> > * Added comment about cycle counter is fastest one
> >
> > Change from v2 to v3
> > * remove kfree
> >
> > Change from V1 to V2
> > * update Kconfig by use i.MX8 instead of i.MX8 QXP
> > * remove gpl statememnt since SPDX tag
> > * use dev_kzalloc
> > * use dev_err
> > * commit message show axi_read 0x41\axi_write 0x42
> > * commit message show cycles must be enabled
> > * Irq only issue at cycles overflow
> > * use NUM_COUNTER
> > * use devm_request_irq
> > * add hotplug callback to handle context migration
> >
> > drivers/perf/Kconfig | 7 +
> > drivers/perf/Makefile | 1 +
> > drivers/perf/fsl_imx8_ddr_perf.c | 573 +++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 581 insertions(+)
> > create mode 100644 drivers/perf/fsl_imx8_ddr_perf.c
> >
> > diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig
> > index af9bc17..e567437 100644
> > --- a/drivers/perf/Kconfig
> > +++ b/drivers/perf/Kconfig
> > @@ -61,6 +61,13 @@ config ARM_DSU_PMU
> > system, control logic. The PMU allows counting various events related
> > to DSU.
> >
> > +config FSL_IMX8_DDR_PMU
> > + tristate "Freescale i.MX8 DDR perf monitor"
> > + depends on ARCH_MXC
> > + help
> > + Provides support for ddr perfomance monitor in i.MX8. Provide memory
> > + througput information.
> > +
> > config HISI_PMU
> > bool "HiSilicon SoC PMU"
> > depends on ARM64 && ACPI
> > diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile
> > index 909f27f..0bc066b 100644
> > --- a/drivers/perf/Makefile
> > +++ b/drivers/perf/Makefile
> > @@ -4,6 +4,7 @@ obj-$(CONFIG_ARM_CCN) += arm-ccn.o
> > obj-$(CONFIG_ARM_DSU_PMU) += arm_dsu_pmu.o
> > obj-$(CONFIG_ARM_PMU) += arm_pmu.o arm_pmu_platform.o
> > obj-$(CONFIG_ARM_PMU_ACPI) += arm_pmu_acpi.o
> > +obj-$(CONFIG_FSL_IMX8_DDR_PMU) += fsl_imx8_ddr_perf.o
> > obj-$(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_imx8_ddr_perf.c b/drivers/perf/fsl_imx8_ddr_perf.c
> > new file mode 100644
> > index 0000000..3d02daf
> > --- /dev/null
> > +++ b/drivers/perf/fsl_imx8_ddr_perf.c
> > @@ -0,0 +1,573 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright 2017 NXP
> > + * Copyright 2016 Freescale Semiconductor, Inc.
> > + */
> > +
> > +#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_CSV_SHIFT 24
> > +#define CNTL_CSV_MASK (0xFF << CNTL_CSV_SHIFT)
> > +
> > +#define EVENT_CYCLES_ID 0
> > +#define EVENT_CYCLES_COUNTER 0
> > +#define NUM_COUNTER 4
> > +#define MAX_EVENT 3
> > +#define EVENT_AXI_READ 0x41
> > +#define EVENT_AXI_WRITE 0x42
> > +
> > +#define to_ddr_pmu(p) container_of(p, struct ddr_pmu, pmu)
> > +
> > +#define DDR_PERF_DEV_NAME "ddr_perf"
> > +
> > +static DEFINE_IDA(ddr_ida);
> > +
> > +PMU_EVENT_ATTR_STRING(cycles, ddr_perf_cycles, "event=0x00");
> > +PMU_EVENT_ATTR_STRING(selfresh, ddr_perf_selfresh, "event=0x01");
> > +PMU_EVENT_ATTR_STRING(read-access, ddr_perf_read_accesses, "event=0x04");
> > +PMU_EVENT_ATTR_STRING(write-access, ddr_perf_write_accesses, "event=0x05");
> > +PMU_EVENT_ATTR_STRING(read-queue-depth, ddr_perf_read_queue_depth,
> > + "event=0x08");
> > +PMU_EVENT_ATTR_STRING(write-queue-depth, ddr_perf_write_queue_depth,
> > + "event=0x09");
> > +PMU_EVENT_ATTR_STRING(lp-read-credit-cnt, ddr_perf_lp_read_credit_cnt,
> > + "event=0x10");
> > +PMU_EVENT_ATTR_STRING(hp-read-credit-cnt, ddr_perf_hp_read_credit_cnt,
> > + "event=0x11");
> > +PMU_EVENT_ATTR_STRING(write-credit-cnt, ddr_perf_write_credit_cnt,
> > + "event=0x12");
> > +PMU_EVENT_ATTR_STRING(read-command, ddr_perf_read_command, "event=0x20");
> > +PMU_EVENT_ATTR_STRING(write-command, ddr_perf_write_command, "event=0x21");
> > +PMU_EVENT_ATTR_STRING(read-modify-write-command,
> > + ddr_perf_read_modify_write_command, "event=0x22");
> > +PMU_EVENT_ATTR_STRING(hp-read, ddr_perf_hp_read, "event=0x23");
> > +PMU_EVENT_ATTR_STRING(hp-req-nodcredit, ddr_perf_hp_req_nocredit, "event=0x24");
> > +PMU_EVENT_ATTR_STRING(hp-xact-credit, ddr_perf_hp_xact_credit, "event=0x25");
> > +PMU_EVENT_ATTR_STRING(lp-req-nocredit, ddr_perf_lp_req_nocredit, "event=0x26");
> > +PMU_EVENT_ATTR_STRING(lp-xact-credit, ddr_perf_lp_xact_credit, "event=0x27");
> > +PMU_EVENT_ATTR_STRING(wr-xact-credit, ddr_perf_wr_xact_credit, "event=0x29");
> > +PMU_EVENT_ATTR_STRING(read-cycles, ddr_perf_read_cycles, "event=0x2a");
> > +PMU_EVENT_ATTR_STRING(write-cycles, ddr_perf_write_cycles, "event=0x2b");
> > +PMU_EVENT_ATTR_STRING(read-write-transition, ddr_perf_read_write_transition,
> > + "event=0x30");
> > +PMU_EVENT_ATTR_STRING(precharge, ddr_perf_precharge, "event=0x31");
> > +PMU_EVENT_ATTR_STRING(activate, ddr_perf_activate, "event=0x32");
> > +PMU_EVENT_ATTR_STRING(load-mode, ddr_perf_load_mode, "event=0x33");
> > +PMU_EVENT_ATTR_STRING(mwr, ddr_perf_mwr, "event=0x34");
> > +PMU_EVENT_ATTR_STRING(read, ddr_perf_read, "event=0x35");
> > +PMU_EVENT_ATTR_STRING(read-activate, ddr_perf_read_activate, "event=0x36");
> > +PMU_EVENT_ATTR_STRING(refresh, ddr_perf_refresh, "event=0x37");
> > +PMU_EVENT_ATTR_STRING(write, ddr_perf_write, "event=0x38");
> > +PMU_EVENT_ATTR_STRING(raw-hazard, ddr_perf_raw_hazard, "event=0x39");
> > +
> > +PMU_EVENT_ATTR_STRING(axid-read, ddr_perf_axid_read,
> > + "event="__stringify(EVENT_AXI_READ));
> > +PMU_EVENT_ATTR_STRING(axid-write, ddr_perf_axid_write,
> > + "event="__stringify(EVENT_AXI_WRITE));
> > +
> > +#define DDR_CAP_AXI_ID 0x1
> > +
> > +static const struct of_device_id imx_ddr_pmu_dt_ids[] = {
> > + { .compatible = "fsl,imx8-ddr-pmu",},
> > + { .compatible = "fsl,imx8m-ddr-pmu", .data = (void *)DDR_CAP_AXI_ID},
> > + { /* sentinel */ }
> > +};
> > +
> > +struct ddr_pmu {
> > + struct pmu pmu;
> > + void __iomem *base;
> > + cpumask_t cpu;
> > + struct hlist_node node;
> > + struct device *dev;
> > + struct perf_event *active_events[NUM_COUNTER];
> > + int total_events;
> > + enum cpuhp_state cpuhp_state;
> > + bool cycles_active;
> > + uintptr_t flags;
> > +};
> > +
> > +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, &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 struct attribute_group ddr_perf_cpumask_attr_group = {
> > + .attrs = ddr_perf_cpumask_attrs,
> > +};
> > +
> > +static struct attribute *ddr_perf_events_attrs[] = {
> > + &ddr_perf_cycles.attr.attr,
> > + &ddr_perf_selfresh.attr.attr,
> > + &ddr_perf_read_accesses.attr.attr,
> > + &ddr_perf_write_accesses.attr.attr,
> > + &ddr_perf_read_queue_depth.attr.attr,
> > + &ddr_perf_write_queue_depth.attr.attr,
> > + &ddr_perf_lp_read_credit_cnt.attr.attr,
> > + &ddr_perf_hp_read_credit_cnt.attr.attr,
> > + &ddr_perf_write_credit_cnt.attr.attr,
> > + &ddr_perf_read_command.attr.attr,
> > + &ddr_perf_write_command.attr.attr,
> > + &ddr_perf_read_modify_write_command.attr.attr,
> > + &ddr_perf_hp_read.attr.attr,
> > + &ddr_perf_hp_req_nocredit.attr.attr,
> > + &ddr_perf_hp_xact_credit.attr.attr,
> > + &ddr_perf_lp_req_nocredit.attr.attr,
> > + &ddr_perf_lp_xact_credit.attr.attr,
> > + &ddr_perf_wr_xact_credit.attr.attr,
> > + &ddr_perf_read_cycles.attr.attr,
> > + &ddr_perf_write_cycles.attr.attr,
> > + &ddr_perf_read_write_transition.attr.attr,
> > + &ddr_perf_precharge.attr.attr,
> > + &ddr_perf_activate.attr.attr,
> > + &ddr_perf_load_mode.attr.attr,
> > + &ddr_perf_mwr.attr.attr,
> > + &ddr_perf_read.attr.attr,
> > + &ddr_perf_read_activate.attr.attr,
> > + &ddr_perf_refresh.attr.attr,
> > + &ddr_perf_write.attr.attr,
> > + &ddr_perf_raw_hazard.attr.attr,
> > + &ddr_perf_axid_read.attr.attr,
> > + &ddr_perf_axid_write.attr.attr,
> > + NULL,
> > +};
> > +
> > +static struct attribute_group ddr_perf_events_attr_group = {
> > + .name = "events",
> > + .attrs = ddr_perf_events_attrs,
> > +};
> > +
> > +PMU_FORMAT_ATTR(event, "config:0-63");
> > +PMU_FORMAT_ATTR(axi_id, "config1:0-63");
> > +
> > +static struct attribute *ddr_perf_format_attrs[] = {
> > + &format_attr_event.attr,
> > + &format_attr_axi_id.attr,
> > + NULL,
> > +};
> > +
> > +static 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,
> > + NULL,
> > +};
> > +
> > +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)
> > + return EVENT_CYCLES_COUNTER;
> > +
> > + for (i = 1; i < NUM_COUNTER; i++)
> > + if (pmu->active_events[i] == NULL)
> > + return i;
> > +
> > + return -ENOENT;
> > +}
> > +
> > +static u32 ddr_perf_free_counter(struct ddr_pmu *pmu, int counter)
> > +{
> > + if (counter < 0 || counter >= NUM_COUNTER)
> > + return -ENOENT;
> > +
> > + pmu->active_events[counter] = NULL;
> > +
> > + return 0;
> > +}
> > +
> > +static u32 ddr_perf_read_counter(struct ddr_pmu *pmu, int counter)
> > +{
> > + return readl(pmu->base + COUNTER_READ + 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;
> > +
> > + 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;
> > + }
> > +
> > + if (event->attr.exclude_user ||
> > + event->attr.exclude_kernel ||
> > + event->attr.exclude_hv ||
> > + event->attr.exclude_idle ||
> > + event->attr.exclude_host ||
> > + event->attr.exclude_guest ||
> > + event->attr.sample_period)
> > + return -EINVAL;
> > +
> > + event->cpu = cpumask_first(&pmu->cpu);
> > + hwc->idx = -1;
> > +
> > + return 0;
> > +}
> > +
> > +
> > +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 delta, prev_raw_count, new_raw_count;
> > + int counter = hwc->idx;
> > +
> > + do {
> > + prev_raw_count = local64_read(&hwc->prev_count);
> > + new_raw_count = ddr_perf_read_counter(pmu, counter);
> > + } while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
> > + new_raw_count) != prev_raw_count);
> > +
> > + delta = (new_raw_count - prev_raw_count) & 0xFFFFFFFF;
> > +
> > + local64_add(delta, &event->count);
> > +}
> > +
> > +static void ddr_perf_event_enable(struct ddr_pmu *pmu, int config,
> > + int counter, bool enable)
> > +{
> > + u8 reg = counter * 4 + COUNTER_CNTL;
> > + int val;
> > +
> > + if (enable) {
> > + /* must disable first, then enable again
> > + * otherwise, cycle counter will not work
> > + * if previous state is enabled.
> > + */
> > + writel(0, pmu->base + reg);
> > + val = CNTL_EN | CNTL_CLEAR;
> > + val |= (config << CNTL_CSV_SHIFT) & CNTL_CSV_MASK;
> > + } else {
> > + /* Disable counter */
> > + val = readl(pmu->base + reg) & CNTL_EN_MASK;
> > + }
> > +
> > + writel(val, pmu->base + reg);
> > +
> > + if (config == EVENT_CYCLES_ID)
> > + pmu->cycles_active = enable;
> > +}
> > +
> > +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;
> > +
> > + if (pmu->flags & DDR_CAP_AXI_ID) {
> > + if (event->attr.config == EVENT_AXI_READ ||
> > + event->attr.config == EVENT_AXI_WRITE) {
> > + int val = event->attr.config1;
> > +
> > + writel(val, pmu->base + COUNTER_DPCR1);
> > + }
> > + }
> > +
> > + local64_set(&hwc->prev_count, 0);
> > +
> > + ddr_perf_event_enable(pmu, event->attr.config, counter, true);
> > + /*
> > + * If the cycles counter wasn't explicitly selected,
> > + * we will enable it now.
> > + * cycles counter must be enabled otherwise other counters will
> > + * stopped.
> > + */
> > + if (counter > 0 && !pmu->cycles_active)
> > + ddr_perf_event_enable(pmu, EVENT_CYCLES_ID,
> > + EVENT_CYCLES_COUNTER, true);
> > +}
> > +
> > +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;
> > +
> > + counter = ddr_perf_alloc_counter(pmu, cfg);
> > + if (counter < 0) {
> > + dev_dbg(pmu->dev, "There are not enough counters\n");
> > + return -EOPNOTSUPP;
> > + }
> > +
> > + pmu->active_events[counter] = event;
> > + pmu->total_events++;
> > + hwc->idx = counter;
> > +
> > + if (flags & PERF_EF_START)
> > + ddr_perf_event_start(event, flags);
> > +
> > + local64_set(&hwc->prev_count, ddr_perf_read_counter(pmu, counter));
> > +
> > + 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_event_enable(pmu, event->attr.config, counter, false);
> > + ddr_perf_event_update(event);
> > +}
> > +
> > +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->total_events--;
> > + hwc->idx = -1;
> > +
> > + /* If all events have stopped, stop the cycles counter as well */
> > + if ((pmu->total_events == 0) && pmu->cycles_active)
> > + ddr_perf_event_enable(pmu, EVENT_CYCLES_ID,
> > + EVENT_CYCLES_COUNTER, false);
> > +}
> > +
> > +static int ddr_perf_init(struct ddr_pmu *pmu, void __iomem *base,
> > + struct device *dev)
> > +{
> > + *pmu = (struct ddr_pmu) {
> > + .pmu = (struct pmu) {
> > + .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,
> > + },
> > + .base = base,
> > + .dev = dev,
> > + };
> > +
> > + return ida_simple_get(&ddr_ida, 0, 0, GFP_KERNEL);
> > +}
> > +
> > +static irqreturn_t ddr_perf_irq_handler(int irq, void *p)
> > +{
> > + int i;
> > + u8 reg;
> > + int val;
> > + int counter;
> > + struct ddr_pmu *pmu = (struct ddr_pmu *) p;
> > + struct perf_event *event;
> > +
> > + /* Only cycles counter overflowed can issue irq. all counters will
> > + * be stopped when cycles counter overflow. but other counter don't stop
> > + * when overflow happen. Update all of the local counter values,
> > + * then reset the cycles counter, so the others can continue
> > + * counting. cycles counter is fastest counter in all events. at last
> > + * 4 times than other counters.
> > + */
> > + for (i = 0; i < NUM_COUNTER; i++) {
> > +
> > + if (!pmu->active_events[i])
> > + continue;
> > +
> > + event = pmu->active_events[i];
> > + counter = event->hw.idx;
> > + reg = counter * 4 + COUNTER_CNTL;
> > + val = readl(pmu->base + reg);
> > +
> > + ddr_perf_event_update(event);
> > +
> > + if (counter == EVENT_CYCLES_COUNTER) {
> > + ddr_perf_event_enable(pmu,
> > + EVENT_CYCLES_ID,
> > + EVENT_CYCLES_COUNTER,
> > + true);
> > + ddr_perf_event_update(event);
> > + }
> > + }
> > +
> > + 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 (!cpumask_test_and_clear_cpu(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);
> > + cpumask_set_cpu(target, &pmu->cpu);
> > +
> > + return 0;
> > +}
> > +
> > +static int ddr_perf_probe(struct platform_device *pdev)
> > +{
> > + struct ddr_pmu *pmu;
> > + struct device_node *np;
> > + void __iomem *base;
> > + struct resource *iomem;
> > + char *name;
> > + char *hpname;
> > + int num;
> > + int ret;
> > + u32 irq;
> > + const struct of_device_id *of_id =
> > + of_match_device(imx_ddr_pmu_dt_ids, &pdev->dev);
> > +
> > + iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > + base = devm_ioremap_resource(&pdev->dev, iomem);
> > + 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);
> > +
> > + name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "ddr%d", num);
> > + if (!name)
> > + return -ENOMEM;
> > +
> > + hpname = devm_kasprintf(&pdev->dev, GFP_KERNEL,
> > + "perf/imx/ddr%d:online", num);
> > + if (!hpname)
> > + return -ENOMEM;
> > +
> > + pmu->flags = (uintptr_t) of_id->data;
> > +
> > + cpumask_set_cpu(raw_smp_processor_id(), &pmu->cpu);
> > + ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, hpname, NULL,
> > + ddr_perf_offline_cpu);
> > +
> > + if (ret < 0) {
> > + dev_err(&pdev->dev, "cpuhp_setup_state_multi failed\n");
> > + goto ddr_perf_err;
> > + }
> > +
> > + pmu->cpuhp_state = ret;
> > +
> > + /* Register the pmu instance for cpu hotplug */
> > + cpuhp_state_add_instance_nocalls(pmu->cpuhp_state, &pmu->node);
> > +
> > + ret = perf_pmu_register(&(pmu->pmu), name, -1);
> > + if (ret)
> > + goto ddr_perf_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_irq_err;
> > + }
> > +
> > + ret = devm_request_irq(&pdev->dev, irq,
> > + ddr_perf_irq_handler,
> > + IRQF_TRIGGER_RISING | IRQF_ONESHOT,
> > + DDR_PERF_DEV_NAME,
> > + pmu);
> > + if (ret < 0) {
> > + dev_err(&pdev->dev, "Request irq failed: %d", ret);
> > + goto ddr_perf_irq_err;
> > + }
> > +
> > + return 0;
> > +
> > +ddr_perf_irq_err:
> > + perf_pmu_unregister(&(pmu->pmu));
> > +
> > +ddr_perf_err:
> > + if (pmu->cpuhp_state)
> > + cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
> > +
> > + 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);
> > + perf_pmu_unregister(&pmu->pmu);
> > +
> > + return 0;
> > +}
> > +
> > +static struct platform_driver imx_ddr_pmu_driver = {
> > + .driver = {
> > + .name = "imx-ddr-pmu",
> > + .of_match_table = imx_ddr_pmu_dt_ids,
> > + },
> > + .probe = ddr_perf_probe,
> > + .remove = ddr_perf_remove,
> > +};
> > +
> > +static int __init imx_ddr_pmu_init(void)
> > +{
> > + return platform_driver_register(&imx_ddr_pmu_driver);
> > +}
> > +
> > +module_init(imx_ddr_pmu_init);
> > +
> > --
> > 2.5.2
> >
