linux/arch/arm/mach-imx/mmdc.c

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/*
* Copyright 2011,2016 Freescale Semiconductor, Inc.
* Copyright 2011 Linaro Ltd.
*
* The code contained herein is licensed under the GNU General Public
* License. You may obtain a copy of the GNU General Public License
* Version 2 or later at the following locations:
*
* http://www.opensource.org/licenses/gpl-license.html
* http://www.gnu.org/copyleft/gpl.html
*/
#include <linux/hrtimer.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/perf_event.h>
#include <linux/slab.h>
#include "common.h"
#define MMDC_MAPSR 0x404
#define BP_MMDC_MAPSR_PSD 0
#define BP_MMDC_MAPSR_PSS 4
#define MMDC_MDMISC 0x18
#define BM_MMDC_MDMISC_DDR_TYPE 0x18
#define BP_MMDC_MDMISC_DDR_TYPE 0x3
#define TOTAL_CYCLES 0x0
#define BUSY_CYCLES 0x1
#define READ_ACCESSES 0x2
#define WRITE_ACCESSES 0x3
#define READ_BYTES 0x4
#define WRITE_BYTES 0x5
/* Enables, resets, freezes, overflow profiling*/
#define DBG_DIS 0x0
#define DBG_EN 0x1
#define DBG_RST 0x2
#define PRF_FRZ 0x4
#define CYC_OVF 0x8
#define PROFILE_SEL 0x10
#define MMDC_MADPCR0 0x410
#define MMDC_MADPSR0 0x418
#define MMDC_MADPSR1 0x41C
#define MMDC_MADPSR2 0x420
#define MMDC_MADPSR3 0x424
#define MMDC_MADPSR4 0x428
#define MMDC_MADPSR5 0x42C
#define MMDC_NUM_COUNTERS 6
#define MMDC_FLAG_PROFILE_SEL 0x1
#define to_mmdc_pmu(p) container_of(p, struct mmdc_pmu, pmu)
static int ddr_type;
struct fsl_mmdc_devtype_data {
unsigned int flags;
};
static const struct fsl_mmdc_devtype_data imx6q_data = {
};
static const struct fsl_mmdc_devtype_data imx6qp_data = {
.flags = MMDC_FLAG_PROFILE_SEL,
};
static const struct of_device_id imx_mmdc_dt_ids[] = {
{ .compatible = "fsl,imx6q-mmdc", .data = (void *)&imx6q_data},
{ .compatible = "fsl,imx6qp-mmdc", .data = (void *)&imx6qp_data},
{ /* sentinel */ }
};
#ifdef CONFIG_PERF_EVENTS
static enum cpuhp_state cpuhp_mmdc_state;
static DEFINE_IDA(mmdc_ida);
PMU_EVENT_ATTR_STRING(total-cycles, mmdc_pmu_total_cycles, "event=0x00")
PMU_EVENT_ATTR_STRING(busy-cycles, mmdc_pmu_busy_cycles, "event=0x01")
PMU_EVENT_ATTR_STRING(read-accesses, mmdc_pmu_read_accesses, "event=0x02")
PMU_EVENT_ATTR_STRING(write-accesses, mmdc_pmu_write_accesses, "config=0x03")
PMU_EVENT_ATTR_STRING(read-bytes, mmdc_pmu_read_bytes, "event=0x04")
PMU_EVENT_ATTR_STRING(read-bytes.unit, mmdc_pmu_read_bytes_unit, "MB");
PMU_EVENT_ATTR_STRING(read-bytes.scale, mmdc_pmu_read_bytes_scale, "0.000001");
PMU_EVENT_ATTR_STRING(write-bytes, mmdc_pmu_write_bytes, "event=0x05")
PMU_EVENT_ATTR_STRING(write-bytes.unit, mmdc_pmu_write_bytes_unit, "MB");
PMU_EVENT_ATTR_STRING(write-bytes.scale, mmdc_pmu_write_bytes_scale, "0.000001");
struct mmdc_pmu {
struct pmu pmu;
void __iomem *mmdc_base;
cpumask_t cpu;
struct hrtimer hrtimer;
unsigned int active_events;
struct device *dev;
struct perf_event *mmdc_events[MMDC_NUM_COUNTERS];
struct hlist_node node;
struct fsl_mmdc_devtype_data *devtype_data;
};
/*
* Polling period is set to one second, overflow of total-cycles (the fastest
* increasing counter) takes ten seconds so one second is safe
*/
static unsigned int mmdc_pmu_poll_period_us = 1000000;
module_param_named(pmu_pmu_poll_period_us, mmdc_pmu_poll_period_us, uint,
S_IRUGO | S_IWUSR);
static ktime_t mmdc_pmu_timer_period(void)
{
return ns_to_ktime((u64)mmdc_pmu_poll_period_us * 1000);
}
static ssize_t mmdc_pmu_cpumask_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mmdc_pmu *pmu_mmdc = dev_get_drvdata(dev);
return cpumap_print_to_pagebuf(true, buf, &pmu_mmdc->cpu);
}
static struct device_attribute mmdc_pmu_cpumask_attr =
__ATTR(cpumask, S_IRUGO, mmdc_pmu_cpumask_show, NULL);
static struct attribute *mmdc_pmu_cpumask_attrs[] = {
&mmdc_pmu_cpumask_attr.attr,
NULL,
};
static struct attribute_group mmdc_pmu_cpumask_attr_group = {
.attrs = mmdc_pmu_cpumask_attrs,
};
static struct attribute *mmdc_pmu_events_attrs[] = {
&mmdc_pmu_total_cycles.attr.attr,
&mmdc_pmu_busy_cycles.attr.attr,
&mmdc_pmu_read_accesses.attr.attr,
&mmdc_pmu_write_accesses.attr.attr,
&mmdc_pmu_read_bytes.attr.attr,
&mmdc_pmu_read_bytes_unit.attr.attr,
&mmdc_pmu_read_bytes_scale.attr.attr,
&mmdc_pmu_write_bytes.attr.attr,
&mmdc_pmu_write_bytes_unit.attr.attr,
&mmdc_pmu_write_bytes_scale.attr.attr,
NULL,
};
static struct attribute_group mmdc_pmu_events_attr_group = {
.name = "events",
.attrs = mmdc_pmu_events_attrs,
};
PMU_FORMAT_ATTR(event, "config:0-63");
static struct attribute *mmdc_pmu_format_attrs[] = {
&format_attr_event.attr,
NULL,
};
static struct attribute_group mmdc_pmu_format_attr_group = {
.name = "format",
.attrs = mmdc_pmu_format_attrs,
};
static const struct attribute_group *attr_groups[] = {
&mmdc_pmu_events_attr_group,
&mmdc_pmu_format_attr_group,
&mmdc_pmu_cpumask_attr_group,
NULL,
};
static u32 mmdc_pmu_read_counter(struct mmdc_pmu *pmu_mmdc, int cfg)
{
void __iomem *mmdc_base, *reg;
mmdc_base = pmu_mmdc->mmdc_base;
switch (cfg) {
case TOTAL_CYCLES:
reg = mmdc_base + MMDC_MADPSR0;
break;
case BUSY_CYCLES:
reg = mmdc_base + MMDC_MADPSR1;
break;
case READ_ACCESSES:
reg = mmdc_base + MMDC_MADPSR2;
break;
case WRITE_ACCESSES:
reg = mmdc_base + MMDC_MADPSR3;
break;
case READ_BYTES:
reg = mmdc_base + MMDC_MADPSR4;
break;
case WRITE_BYTES:
reg = mmdc_base + MMDC_MADPSR5;
break;
default:
return WARN_ONCE(1,
"invalid configuration %d for mmdc counter", cfg);
}
return readl(reg);
}
static int mmdc_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
{
struct mmdc_pmu *pmu_mmdc = hlist_entry_safe(node, struct mmdc_pmu, node);
int target;
if (!cpumask_test_and_clear_cpu(cpu, &pmu_mmdc->cpu))
return 0;
target = cpumask_any_but(cpu_online_mask, cpu);
if (target >= nr_cpu_ids)
return 0;
perf_pmu_migrate_context(&pmu_mmdc->pmu, cpu, target);
cpumask_set_cpu(target, &pmu_mmdc->cpu);
return 0;
}
static bool mmdc_pmu_group_event_is_valid(struct perf_event *event,
struct pmu *pmu,
unsigned long *used_counters)
{
int cfg = event->attr.config;
if (is_software_event(event))
return true;
if (event->pmu != pmu)
return false;
return !test_and_set_bit(cfg, used_counters);
}
/*
* Each event has a single fixed-purpose counter, so we can only have a
* single active event for each at any point in time. Here we just check
* for duplicates, and rely on mmdc_pmu_event_init to verify that the HW
* event numbers are valid.
*/
static bool mmdc_pmu_group_is_valid(struct perf_event *event)
{
struct pmu *pmu = event->pmu;
struct perf_event *leader = event->group_leader;
struct perf_event *sibling;
unsigned long counter_mask = 0;
set_bit(leader->attr.config, &counter_mask);
if (event != leader) {
if (!mmdc_pmu_group_event_is_valid(event, pmu, &counter_mask))
return false;
}
list_for_each_entry(sibling, &leader->sibling_list, group_entry) {
if (!mmdc_pmu_group_event_is_valid(sibling, pmu, &counter_mask))
return false;
}
return true;
}
static int mmdc_pmu_event_init(struct perf_event *event)
{
struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
int cfg = event->attr.config;
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_mmdc->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;
if (cfg < 0 || cfg >= MMDC_NUM_COUNTERS)
return -EINVAL;
if (!mmdc_pmu_group_is_valid(event))
return -EINVAL;
event->cpu = cpumask_first(&pmu_mmdc->cpu);
return 0;
}
static void mmdc_pmu_event_update(struct perf_event *event)
{
struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
u64 delta, prev_raw_count, new_raw_count;
do {
prev_raw_count = local64_read(&hwc->prev_count);
new_raw_count = mmdc_pmu_read_counter(pmu_mmdc,
event->attr.config);
} 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 mmdc_pmu_event_start(struct perf_event *event, int flags)
{
struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
void __iomem *mmdc_base, *reg;
u32 val;
mmdc_base = pmu_mmdc->mmdc_base;
reg = mmdc_base + MMDC_MADPCR0;
/*
* hrtimer is required because mmdc does not provide an interrupt so
* polling is necessary
*/
hrtimer_start(&pmu_mmdc->hrtimer, mmdc_pmu_timer_period(),
HRTIMER_MODE_REL_PINNED);
local64_set(&hwc->prev_count, 0);
writel(DBG_RST, reg);
val = DBG_EN;
if (pmu_mmdc->devtype_data->flags & MMDC_FLAG_PROFILE_SEL)
val |= PROFILE_SEL;
writel(val, reg);
}
static int mmdc_pmu_event_add(struct perf_event *event, int flags)
{
struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
int cfg = event->attr.config;
if (flags & PERF_EF_START)
mmdc_pmu_event_start(event, flags);
if (pmu_mmdc->mmdc_events[cfg] != NULL)
return -EAGAIN;
pmu_mmdc->mmdc_events[cfg] = event;
pmu_mmdc->active_events++;
local64_set(&hwc->prev_count, mmdc_pmu_read_counter(pmu_mmdc, cfg));
return 0;
}
static void mmdc_pmu_event_stop(struct perf_event *event, int flags)
{
struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
void __iomem *mmdc_base, *reg;
mmdc_base = pmu_mmdc->mmdc_base;
reg = mmdc_base + MMDC_MADPCR0;
writel(PRF_FRZ, reg);
mmdc_pmu_event_update(event);
}
static void mmdc_pmu_event_del(struct perf_event *event, int flags)
{
struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
int cfg = event->attr.config;
pmu_mmdc->mmdc_events[cfg] = NULL;
pmu_mmdc->active_events--;
if (pmu_mmdc->active_events == 0)
hrtimer_cancel(&pmu_mmdc->hrtimer);
mmdc_pmu_event_stop(event, PERF_EF_UPDATE);
}
static void mmdc_pmu_overflow_handler(struct mmdc_pmu *pmu_mmdc)
{
int i;
for (i = 0; i < MMDC_NUM_COUNTERS; i++) {
struct perf_event *event = pmu_mmdc->mmdc_events[i];
if (event)
mmdc_pmu_event_update(event);
}
}
static enum hrtimer_restart mmdc_pmu_timer_handler(struct hrtimer *hrtimer)
{
struct mmdc_pmu *pmu_mmdc = container_of(hrtimer, struct mmdc_pmu,
hrtimer);
mmdc_pmu_overflow_handler(pmu_mmdc);
hrtimer_forward_now(hrtimer, mmdc_pmu_timer_period());
return HRTIMER_RESTART;
}
static int mmdc_pmu_init(struct mmdc_pmu *pmu_mmdc,
void __iomem *mmdc_base, struct device *dev)
{
int mmdc_num;
*pmu_mmdc = (struct mmdc_pmu) {
.pmu = (struct pmu) {
.task_ctx_nr = perf_invalid_context,
.attr_groups = attr_groups,
.event_init = mmdc_pmu_event_init,
.add = mmdc_pmu_event_add,
.del = mmdc_pmu_event_del,
.start = mmdc_pmu_event_start,
.stop = mmdc_pmu_event_stop,
.read = mmdc_pmu_event_update,
},
.mmdc_base = mmdc_base,
.dev = dev,
.active_events = 0,
};
mmdc_num = ida_simple_get(&mmdc_ida, 0, 0, GFP_KERNEL);
return mmdc_num;
}
static int imx_mmdc_remove(struct platform_device *pdev)
{
struct mmdc_pmu *pmu_mmdc = platform_get_drvdata(pdev);
ARM/imx/mmcd: Fix broken cpu hotplug handling The cpu hotplug support of this perf driver is broken in several ways: 1) It adds a instance before setting up the state. 2) The state for the instance is different from the state of the callback. It's just a randomly chosen state. 3) The instance registration is not error checked so nobody noticed that the call can never succeed. 4) The state for the multi install callbacks is chosen randomly and overwrites existing state. This is now prevented by the core code so the call is guaranteed to fail. 5) The error exit path in the init function leaves the instance registered and then frees the memory which contains the enqueued hlist node. 6) The remove function is removing the state and not the instance. Fix it by: - Setting up the state before adding instances. Use a dynamically allocated state for it. - Installing instances after the state has been set up - Removing the instance in the error path before freeing memory - Removing the instance not the state in the driver remove callback While at is use raw_cpu_processor_id(), because cpu_processor_id() cannot be used in preemptible context, and set the driver data after successful registration of the pmu. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Shawn Guo <shawnguo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Frank Li <frank.li@nxp.com> Cc: Zhengyu Shen <zhengyu.shen@nxp.com> Link: http://lkml.kernel.org/r/20161221192111.596204211@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-22 03:19:48 +08:00
cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
perf_pmu_unregister(&pmu_mmdc->pmu);
kfree(pmu_mmdc);
return 0;
}
static int imx_mmdc_perf_init(struct platform_device *pdev, void __iomem *mmdc_base)
{
struct mmdc_pmu *pmu_mmdc;
char *name;
int mmdc_num;
int ret;
const struct of_device_id *of_id =
of_match_device(imx_mmdc_dt_ids, &pdev->dev);
pmu_mmdc = kzalloc(sizeof(*pmu_mmdc), GFP_KERNEL);
if (!pmu_mmdc) {
pr_err("failed to allocate PMU device!\n");
return -ENOMEM;
}
ARM/imx/mmcd: Fix broken cpu hotplug handling The cpu hotplug support of this perf driver is broken in several ways: 1) It adds a instance before setting up the state. 2) The state for the instance is different from the state of the callback. It's just a randomly chosen state. 3) The instance registration is not error checked so nobody noticed that the call can never succeed. 4) The state for the multi install callbacks is chosen randomly and overwrites existing state. This is now prevented by the core code so the call is guaranteed to fail. 5) The error exit path in the init function leaves the instance registered and then frees the memory which contains the enqueued hlist node. 6) The remove function is removing the state and not the instance. Fix it by: - Setting up the state before adding instances. Use a dynamically allocated state for it. - Installing instances after the state has been set up - Removing the instance in the error path before freeing memory - Removing the instance not the state in the driver remove callback While at is use raw_cpu_processor_id(), because cpu_processor_id() cannot be used in preemptible context, and set the driver data after successful registration of the pmu. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Shawn Guo <shawnguo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Frank Li <frank.li@nxp.com> Cc: Zhengyu Shen <zhengyu.shen@nxp.com> Link: http://lkml.kernel.org/r/20161221192111.596204211@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-22 03:19:48 +08:00
/* The first instance registers the hotplug state */
if (!cpuhp_mmdc_state) {
ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
"perf/arm/mmdc:online", NULL,
mmdc_pmu_offline_cpu);
if (ret < 0) {
pr_err("cpuhp_setup_state_multi failed\n");
goto pmu_free;
}
cpuhp_mmdc_state = ret;
}
mmdc_num = mmdc_pmu_init(pmu_mmdc, mmdc_base, &pdev->dev);
if (mmdc_num == 0)
name = "mmdc";
else
name = devm_kasprintf(&pdev->dev,
GFP_KERNEL, "mmdc%d", mmdc_num);
pmu_mmdc->devtype_data = (struct fsl_mmdc_devtype_data *)of_id->data;
hrtimer_init(&pmu_mmdc->hrtimer, CLOCK_MONOTONIC,
HRTIMER_MODE_REL);
pmu_mmdc->hrtimer.function = mmdc_pmu_timer_handler;
ARM/imx/mmcd: Fix broken cpu hotplug handling The cpu hotplug support of this perf driver is broken in several ways: 1) It adds a instance before setting up the state. 2) The state for the instance is different from the state of the callback. It's just a randomly chosen state. 3) The instance registration is not error checked so nobody noticed that the call can never succeed. 4) The state for the multi install callbacks is chosen randomly and overwrites existing state. This is now prevented by the core code so the call is guaranteed to fail. 5) The error exit path in the init function leaves the instance registered and then frees the memory which contains the enqueued hlist node. 6) The remove function is removing the state and not the instance. Fix it by: - Setting up the state before adding instances. Use a dynamically allocated state for it. - Installing instances after the state has been set up - Removing the instance in the error path before freeing memory - Removing the instance not the state in the driver remove callback While at is use raw_cpu_processor_id(), because cpu_processor_id() cannot be used in preemptible context, and set the driver data after successful registration of the pmu. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Shawn Guo <shawnguo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Frank Li <frank.li@nxp.com> Cc: Zhengyu Shen <zhengyu.shen@nxp.com> Link: http://lkml.kernel.org/r/20161221192111.596204211@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-22 03:19:48 +08:00
cpumask_set_cpu(raw_smp_processor_id(), &pmu_mmdc->cpu);
/* Register the pmu instance for cpu hotplug */
cpuhp_state_add_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
ret = perf_pmu_register(&(pmu_mmdc->pmu), name, -1);
if (ret)
goto pmu_register_err;
ARM/imx/mmcd: Fix broken cpu hotplug handling The cpu hotplug support of this perf driver is broken in several ways: 1) It adds a instance before setting up the state. 2) The state for the instance is different from the state of the callback. It's just a randomly chosen state. 3) The instance registration is not error checked so nobody noticed that the call can never succeed. 4) The state for the multi install callbacks is chosen randomly and overwrites existing state. This is now prevented by the core code so the call is guaranteed to fail. 5) The error exit path in the init function leaves the instance registered and then frees the memory which contains the enqueued hlist node. 6) The remove function is removing the state and not the instance. Fix it by: - Setting up the state before adding instances. Use a dynamically allocated state for it. - Installing instances after the state has been set up - Removing the instance in the error path before freeing memory - Removing the instance not the state in the driver remove callback While at is use raw_cpu_processor_id(), because cpu_processor_id() cannot be used in preemptible context, and set the driver data after successful registration of the pmu. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Shawn Guo <shawnguo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Frank Li <frank.li@nxp.com> Cc: Zhengyu Shen <zhengyu.shen@nxp.com> Link: http://lkml.kernel.org/r/20161221192111.596204211@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-22 03:19:48 +08:00
platform_set_drvdata(pdev, pmu_mmdc);
return 0;
pmu_register_err:
pr_warn("MMDC Perf PMU failed (%d), disabled\n", ret);
ARM/imx/mmcd: Fix broken cpu hotplug handling The cpu hotplug support of this perf driver is broken in several ways: 1) It adds a instance before setting up the state. 2) The state for the instance is different from the state of the callback. It's just a randomly chosen state. 3) The instance registration is not error checked so nobody noticed that the call can never succeed. 4) The state for the multi install callbacks is chosen randomly and overwrites existing state. This is now prevented by the core code so the call is guaranteed to fail. 5) The error exit path in the init function leaves the instance registered and then frees the memory which contains the enqueued hlist node. 6) The remove function is removing the state and not the instance. Fix it by: - Setting up the state before adding instances. Use a dynamically allocated state for it. - Installing instances after the state has been set up - Removing the instance in the error path before freeing memory - Removing the instance not the state in the driver remove callback While at is use raw_cpu_processor_id(), because cpu_processor_id() cannot be used in preemptible context, and set the driver data after successful registration of the pmu. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Shawn Guo <shawnguo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Frank Li <frank.li@nxp.com> Cc: Zhengyu Shen <zhengyu.shen@nxp.com> Link: http://lkml.kernel.org/r/20161221192111.596204211@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-22 03:19:48 +08:00
cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
hrtimer_cancel(&pmu_mmdc->hrtimer);
ARM/imx/mmcd: Fix broken cpu hotplug handling The cpu hotplug support of this perf driver is broken in several ways: 1) It adds a instance before setting up the state. 2) The state for the instance is different from the state of the callback. It's just a randomly chosen state. 3) The instance registration is not error checked so nobody noticed that the call can never succeed. 4) The state for the multi install callbacks is chosen randomly and overwrites existing state. This is now prevented by the core code so the call is guaranteed to fail. 5) The error exit path in the init function leaves the instance registered and then frees the memory which contains the enqueued hlist node. 6) The remove function is removing the state and not the instance. Fix it by: - Setting up the state before adding instances. Use a dynamically allocated state for it. - Installing instances after the state has been set up - Removing the instance in the error path before freeing memory - Removing the instance not the state in the driver remove callback While at is use raw_cpu_processor_id(), because cpu_processor_id() cannot be used in preemptible context, and set the driver data after successful registration of the pmu. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Shawn Guo <shawnguo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Frank Li <frank.li@nxp.com> Cc: Zhengyu Shen <zhengyu.shen@nxp.com> Link: http://lkml.kernel.org/r/20161221192111.596204211@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-22 03:19:48 +08:00
pmu_free:
kfree(pmu_mmdc);
return ret;
}
#else
#define imx_mmdc_remove NULL
#define imx_mmdc_perf_init(pdev, mmdc_base) 0
#endif
static int imx_mmdc_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
void __iomem *mmdc_base, *reg;
u32 val;
int timeout = 0x400;
mmdc_base = of_iomap(np, 0);
WARN_ON(!mmdc_base);
reg = mmdc_base + MMDC_MDMISC;
/* Get ddr type */
val = readl_relaxed(reg);
ddr_type = (val & BM_MMDC_MDMISC_DDR_TYPE) >>
BP_MMDC_MDMISC_DDR_TYPE;
reg = mmdc_base + MMDC_MAPSR;
/* Enable automatic power saving */
val = readl_relaxed(reg);
val &= ~(1 << BP_MMDC_MAPSR_PSD);
writel_relaxed(val, reg);
/* Ensure it's successfully enabled */
while (!(readl_relaxed(reg) & 1 << BP_MMDC_MAPSR_PSS) && --timeout)
cpu_relax();
if (unlikely(!timeout)) {
pr_warn("%s: failed to enable automatic power saving\n",
__func__);
return -EBUSY;
}
return imx_mmdc_perf_init(pdev, mmdc_base);
}
int imx_mmdc_get_ddr_type(void)
{
return ddr_type;
}
static struct platform_driver imx_mmdc_driver = {
.driver = {
.name = "imx-mmdc",
.of_match_table = imx_mmdc_dt_ids,
},
.probe = imx_mmdc_probe,
.remove = imx_mmdc_remove,
};
static int __init imx_mmdc_init(void)
{
return platform_driver_register(&imx_mmdc_driver);
}
postcore_initcall(imx_mmdc_init);