linux/drivers/perf/fsl_imx8_ddr_perf.c
Xu Yang f4e2bd91dd perf/imx_ddr: don't enable counter0 if none of 4 counters are used
In current driver, counter0 will be enabled after ddr_perf_pmu_enable()
is called even though none of the 4 counters are used. This will cause
counter0 continue to count until ddr_perf_pmu_disabled() is called. If
pmu is not disabled all the time, the pmu interrupt will be asserted
from time to time due to counter0 will overflow and irq handler will
clear it. It's not an expected behavior. This patch will not enable
counter0 if none of 4 counters are used.

Fixes: 9a66d36cc7 ("drivers/perf: imx_ddr: Add DDR performance counter support to perf")
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20230811015438.1999307-2-xu.yang_2@nxp.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-08-16 14:34:51 +01:00

809 lines
21 KiB
C

// 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_irq.h>
#include <linux/perf_event.h>
#include <linux/platform_device.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];
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;
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);
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");