linux/drivers/perf/arm_dsu_pmu.c
Thomas Gleixner 41ea281724 perf/arm-dsu: Use irq_set_affinity()
The driver uses irq_set_affinity_hint() to set the affinity for the PMU
interrupts, which relies on the undocumented side effect that this function
actually sets the affinity under the hood.

Setting an hint is clearly not a guarantee and for these PMU interrupts an
affinity hint, which is supposed to guide userspace for setting affinity,
is beyond pointless, because the affinity of these interrupts cannot be
modified from user space.

Aside of that the error checks are bogus because the only error which is
returned from irq_set_affinity_hint() is when there is no irq descriptor
for the interrupt number, but not when the affinity set fails. That's on
purpose because the hint can point to an offline CPU.

Replace the mindless abuse with irq_set_affinity().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20210518093118.505110632@linutronix.de
Signed-off-by: Will Deacon <will@kernel.org>
2021-05-24 11:02:00 +01:00

876 lines
22 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* ARM DynamIQ Shared Unit (DSU) PMU driver
*
* Copyright (C) ARM Limited, 2017.
*
* Based on ARM CCI-PMU, ARMv8 PMU-v3 drivers.
*/
#define PMUNAME "arm_dsu"
#define DRVNAME PMUNAME "_pmu"
#define pr_fmt(fmt) DRVNAME ": " fmt
#include <linux/acpi.h>
#include <linux/bitmap.h>
#include <linux/bitops.h>
#include <linux/bug.h>
#include <linux/cpumask.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/perf_event.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/smp.h>
#include <linux/sysfs.h>
#include <linux/types.h>
#include <asm/arm_dsu_pmu.h>
#include <asm/local64.h>
/* PMU event codes */
#define DSU_PMU_EVT_CYCLES 0x11
#define DSU_PMU_EVT_CHAIN 0x1e
#define DSU_PMU_MAX_COMMON_EVENTS 0x40
#define DSU_PMU_MAX_HW_CNTRS 32
#define DSU_PMU_HW_COUNTER_MASK (DSU_PMU_MAX_HW_CNTRS - 1)
#define CLUSTERPMCR_E BIT(0)
#define CLUSTERPMCR_P BIT(1)
#define CLUSTERPMCR_C BIT(2)
#define CLUSTERPMCR_N_SHIFT 11
#define CLUSTERPMCR_N_MASK 0x1f
#define CLUSTERPMCR_IDCODE_SHIFT 16
#define CLUSTERPMCR_IDCODE_MASK 0xff
#define CLUSTERPMCR_IMP_SHIFT 24
#define CLUSTERPMCR_IMP_MASK 0xff
#define CLUSTERPMCR_RES_MASK 0x7e8
#define CLUSTERPMCR_RES_VAL 0x40
#define DSU_ACTIVE_CPU_MASK 0x0
#define DSU_ASSOCIATED_CPU_MASK 0x1
/*
* We use the index of the counters as they appear in the counter
* bit maps in the PMU registers (e.g CLUSTERPMSELR).
* i.e,
* counter 0 - Bit 0
* counter 1 - Bit 1
* ...
* Cycle counter - Bit 31
*/
#define DSU_PMU_IDX_CYCLE_COUNTER 31
/* All event counters are 32bit, with a 64bit Cycle counter */
#define DSU_PMU_COUNTER_WIDTH(idx) \
(((idx) == DSU_PMU_IDX_CYCLE_COUNTER) ? 64 : 32)
#define DSU_PMU_COUNTER_MASK(idx) \
GENMASK_ULL((DSU_PMU_COUNTER_WIDTH((idx)) - 1), 0)
#define DSU_EXT_ATTR(_name, _func, _config) \
(&((struct dev_ext_attribute[]) { \
{ \
.attr = __ATTR(_name, 0444, _func, NULL), \
.var = (void *)_config \
} \
})[0].attr.attr)
#define DSU_EVENT_ATTR(_name, _config) \
DSU_EXT_ATTR(_name, dsu_pmu_sysfs_event_show, (unsigned long)_config)
#define DSU_FORMAT_ATTR(_name, _config) \
DSU_EXT_ATTR(_name, dsu_pmu_sysfs_format_show, (char *)_config)
#define DSU_CPUMASK_ATTR(_name, _config) \
DSU_EXT_ATTR(_name, dsu_pmu_cpumask_show, (unsigned long)_config)
struct dsu_hw_events {
DECLARE_BITMAP(used_mask, DSU_PMU_MAX_HW_CNTRS);
struct perf_event *events[DSU_PMU_MAX_HW_CNTRS];
};
/*
* struct dsu_pmu - DSU PMU descriptor
*
* @pmu_lock : Protects accesses to DSU PMU register from normal vs
* interrupt handler contexts.
* @hw_events : Holds the event counter state.
* @associated_cpus : CPUs attached to the DSU.
* @active_cpu : CPU to which the PMU is bound for accesses.
* @cpuhp_node : Node for CPU hotplug notifier link.
* @num_counters : Number of event counters implemented by the PMU,
* excluding the cycle counter.
* @irq : Interrupt line for counter overflow.
* @cpmceid_bitmap : Bitmap for the availability of architected common
* events (event_code < 0x40).
*/
struct dsu_pmu {
struct pmu pmu;
struct device *dev;
raw_spinlock_t pmu_lock;
struct dsu_hw_events hw_events;
cpumask_t associated_cpus;
cpumask_t active_cpu;
struct hlist_node cpuhp_node;
s8 num_counters;
int irq;
DECLARE_BITMAP(cpmceid_bitmap, DSU_PMU_MAX_COMMON_EVENTS);
};
static unsigned long dsu_pmu_cpuhp_state;
static inline struct dsu_pmu *to_dsu_pmu(struct pmu *pmu)
{
return container_of(pmu, struct dsu_pmu, pmu);
}
static ssize_t dsu_pmu_sysfs_event_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct dev_ext_attribute *eattr = container_of(attr,
struct dev_ext_attribute, attr);
return sysfs_emit(buf, "event=0x%lx\n", (unsigned long)eattr->var);
}
static ssize_t dsu_pmu_sysfs_format_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct dev_ext_attribute *eattr = container_of(attr,
struct dev_ext_attribute, attr);
return sysfs_emit(buf, "%s\n", (char *)eattr->var);
}
static ssize_t dsu_pmu_cpumask_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct pmu *pmu = dev_get_drvdata(dev);
struct dsu_pmu *dsu_pmu = to_dsu_pmu(pmu);
struct dev_ext_attribute *eattr = container_of(attr,
struct dev_ext_attribute, attr);
unsigned long mask_id = (unsigned long)eattr->var;
const cpumask_t *cpumask;
switch (mask_id) {
case DSU_ACTIVE_CPU_MASK:
cpumask = &dsu_pmu->active_cpu;
break;
case DSU_ASSOCIATED_CPU_MASK:
cpumask = &dsu_pmu->associated_cpus;
break;
default:
return 0;
}
return cpumap_print_to_pagebuf(true, buf, cpumask);
}
static struct attribute *dsu_pmu_format_attrs[] = {
DSU_FORMAT_ATTR(event, "config:0-31"),
NULL,
};
static const struct attribute_group dsu_pmu_format_attr_group = {
.name = "format",
.attrs = dsu_pmu_format_attrs,
};
static struct attribute *dsu_pmu_event_attrs[] = {
DSU_EVENT_ATTR(cycles, 0x11),
DSU_EVENT_ATTR(bus_access, 0x19),
DSU_EVENT_ATTR(memory_error, 0x1a),
DSU_EVENT_ATTR(bus_cycles, 0x1d),
DSU_EVENT_ATTR(l3d_cache_allocate, 0x29),
DSU_EVENT_ATTR(l3d_cache_refill, 0x2a),
DSU_EVENT_ATTR(l3d_cache, 0x2b),
DSU_EVENT_ATTR(l3d_cache_wb, 0x2c),
NULL,
};
static umode_t
dsu_pmu_event_attr_is_visible(struct kobject *kobj, struct attribute *attr,
int unused)
{
struct pmu *pmu = dev_get_drvdata(kobj_to_dev(kobj));
struct dsu_pmu *dsu_pmu = to_dsu_pmu(pmu);
struct dev_ext_attribute *eattr = container_of(attr,
struct dev_ext_attribute, attr.attr);
unsigned long evt = (unsigned long)eattr->var;
return test_bit(evt, dsu_pmu->cpmceid_bitmap) ? attr->mode : 0;
}
static const struct attribute_group dsu_pmu_events_attr_group = {
.name = "events",
.attrs = dsu_pmu_event_attrs,
.is_visible = dsu_pmu_event_attr_is_visible,
};
static struct attribute *dsu_pmu_cpumask_attrs[] = {
DSU_CPUMASK_ATTR(cpumask, DSU_ACTIVE_CPU_MASK),
DSU_CPUMASK_ATTR(associated_cpus, DSU_ASSOCIATED_CPU_MASK),
NULL,
};
static const struct attribute_group dsu_pmu_cpumask_attr_group = {
.attrs = dsu_pmu_cpumask_attrs,
};
static const struct attribute_group *dsu_pmu_attr_groups[] = {
&dsu_pmu_cpumask_attr_group,
&dsu_pmu_events_attr_group,
&dsu_pmu_format_attr_group,
NULL,
};
static int dsu_pmu_get_online_cpu_any_but(struct dsu_pmu *dsu_pmu, int cpu)
{
struct cpumask online_supported;
cpumask_and(&online_supported,
&dsu_pmu->associated_cpus, cpu_online_mask);
return cpumask_any_but(&online_supported, cpu);
}
static inline bool dsu_pmu_counter_valid(struct dsu_pmu *dsu_pmu, u32 idx)
{
return (idx < dsu_pmu->num_counters) ||
(idx == DSU_PMU_IDX_CYCLE_COUNTER);
}
static inline u64 dsu_pmu_read_counter(struct perf_event *event)
{
u64 val;
unsigned long flags;
struct dsu_pmu *dsu_pmu = to_dsu_pmu(event->pmu);
int idx = event->hw.idx;
if (WARN_ON(!cpumask_test_cpu(smp_processor_id(),
&dsu_pmu->associated_cpus)))
return 0;
if (!dsu_pmu_counter_valid(dsu_pmu, idx)) {
dev_err(event->pmu->dev,
"Trying reading invalid counter %d\n", idx);
return 0;
}
raw_spin_lock_irqsave(&dsu_pmu->pmu_lock, flags);
if (idx == DSU_PMU_IDX_CYCLE_COUNTER)
val = __dsu_pmu_read_pmccntr();
else
val = __dsu_pmu_read_counter(idx);
raw_spin_unlock_irqrestore(&dsu_pmu->pmu_lock, flags);
return val;
}
static void dsu_pmu_write_counter(struct perf_event *event, u64 val)
{
unsigned long flags;
struct dsu_pmu *dsu_pmu = to_dsu_pmu(event->pmu);
int idx = event->hw.idx;
if (WARN_ON(!cpumask_test_cpu(smp_processor_id(),
&dsu_pmu->associated_cpus)))
return;
if (!dsu_pmu_counter_valid(dsu_pmu, idx)) {
dev_err(event->pmu->dev,
"writing to invalid counter %d\n", idx);
return;
}
raw_spin_lock_irqsave(&dsu_pmu->pmu_lock, flags);
if (idx == DSU_PMU_IDX_CYCLE_COUNTER)
__dsu_pmu_write_pmccntr(val);
else
__dsu_pmu_write_counter(idx, val);
raw_spin_unlock_irqrestore(&dsu_pmu->pmu_lock, flags);
}
static int dsu_pmu_get_event_idx(struct dsu_hw_events *hw_events,
struct perf_event *event)
{
int idx;
unsigned long evtype = event->attr.config;
struct dsu_pmu *dsu_pmu = to_dsu_pmu(event->pmu);
unsigned long *used_mask = hw_events->used_mask;
if (evtype == DSU_PMU_EVT_CYCLES) {
if (test_and_set_bit(DSU_PMU_IDX_CYCLE_COUNTER, used_mask))
return -EAGAIN;
return DSU_PMU_IDX_CYCLE_COUNTER;
}
idx = find_first_zero_bit(used_mask, dsu_pmu->num_counters);
if (idx >= dsu_pmu->num_counters)
return -EAGAIN;
set_bit(idx, hw_events->used_mask);
return idx;
}
static void dsu_pmu_enable_counter(struct dsu_pmu *dsu_pmu, int idx)
{
__dsu_pmu_counter_interrupt_enable(idx);
__dsu_pmu_enable_counter(idx);
}
static void dsu_pmu_disable_counter(struct dsu_pmu *dsu_pmu, int idx)
{
__dsu_pmu_disable_counter(idx);
__dsu_pmu_counter_interrupt_disable(idx);
}
static inline void dsu_pmu_set_event(struct dsu_pmu *dsu_pmu,
struct perf_event *event)
{
int idx = event->hw.idx;
unsigned long flags;
if (!dsu_pmu_counter_valid(dsu_pmu, idx)) {
dev_err(event->pmu->dev,
"Trying to set invalid counter %d\n", idx);
return;
}
raw_spin_lock_irqsave(&dsu_pmu->pmu_lock, flags);
__dsu_pmu_set_event(idx, event->hw.config_base);
raw_spin_unlock_irqrestore(&dsu_pmu->pmu_lock, flags);
}
static void dsu_pmu_event_update(struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
u64 delta, prev_count, new_count;
do {
/* We may also be called from the irq handler */
prev_count = local64_read(&hwc->prev_count);
new_count = dsu_pmu_read_counter(event);
} while (local64_cmpxchg(&hwc->prev_count, prev_count, new_count) !=
prev_count);
delta = (new_count - prev_count) & DSU_PMU_COUNTER_MASK(hwc->idx);
local64_add(delta, &event->count);
}
static void dsu_pmu_read(struct perf_event *event)
{
dsu_pmu_event_update(event);
}
static inline u32 dsu_pmu_get_reset_overflow(void)
{
return __dsu_pmu_get_reset_overflow();
}
/**
* dsu_pmu_set_event_period: Set the period for the counter.
*
* All DSU PMU event counters, except the cycle counter are 32bit
* counters. To handle cases of extreme interrupt latency, we program
* the counter with half of the max count for the counters.
*/
static void dsu_pmu_set_event_period(struct perf_event *event)
{
int idx = event->hw.idx;
u64 val = DSU_PMU_COUNTER_MASK(idx) >> 1;
local64_set(&event->hw.prev_count, val);
dsu_pmu_write_counter(event, val);
}
static irqreturn_t dsu_pmu_handle_irq(int irq_num, void *dev)
{
int i;
bool handled = false;
struct dsu_pmu *dsu_pmu = dev;
struct dsu_hw_events *hw_events = &dsu_pmu->hw_events;
unsigned long overflow;
overflow = dsu_pmu_get_reset_overflow();
if (!overflow)
return IRQ_NONE;
for_each_set_bit(i, &overflow, DSU_PMU_MAX_HW_CNTRS) {
struct perf_event *event = hw_events->events[i];
if (!event)
continue;
dsu_pmu_event_update(event);
dsu_pmu_set_event_period(event);
handled = true;
}
return IRQ_RETVAL(handled);
}
static void dsu_pmu_start(struct perf_event *event, int pmu_flags)
{
struct dsu_pmu *dsu_pmu = to_dsu_pmu(event->pmu);
/* We always reprogram the counter */
if (pmu_flags & PERF_EF_RELOAD)
WARN_ON(!(event->hw.state & PERF_HES_UPTODATE));
dsu_pmu_set_event_period(event);
if (event->hw.idx != DSU_PMU_IDX_CYCLE_COUNTER)
dsu_pmu_set_event(dsu_pmu, event);
event->hw.state = 0;
dsu_pmu_enable_counter(dsu_pmu, event->hw.idx);
}
static void dsu_pmu_stop(struct perf_event *event, int pmu_flags)
{
struct dsu_pmu *dsu_pmu = to_dsu_pmu(event->pmu);
if (event->hw.state & PERF_HES_STOPPED)
return;
dsu_pmu_disable_counter(dsu_pmu, event->hw.idx);
dsu_pmu_event_update(event);
event->hw.state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
}
static int dsu_pmu_add(struct perf_event *event, int flags)
{
struct dsu_pmu *dsu_pmu = to_dsu_pmu(event->pmu);
struct dsu_hw_events *hw_events = &dsu_pmu->hw_events;
struct hw_perf_event *hwc = &event->hw;
int idx;
if (WARN_ON_ONCE(!cpumask_test_cpu(smp_processor_id(),
&dsu_pmu->associated_cpus)))
return -ENOENT;
idx = dsu_pmu_get_event_idx(hw_events, event);
if (idx < 0)
return idx;
hwc->idx = idx;
hw_events->events[idx] = event;
hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
if (flags & PERF_EF_START)
dsu_pmu_start(event, PERF_EF_RELOAD);
perf_event_update_userpage(event);
return 0;
}
static void dsu_pmu_del(struct perf_event *event, int flags)
{
struct dsu_pmu *dsu_pmu = to_dsu_pmu(event->pmu);
struct dsu_hw_events *hw_events = &dsu_pmu->hw_events;
struct hw_perf_event *hwc = &event->hw;
int idx = hwc->idx;
dsu_pmu_stop(event, PERF_EF_UPDATE);
hw_events->events[idx] = NULL;
clear_bit(idx, hw_events->used_mask);
perf_event_update_userpage(event);
}
static void dsu_pmu_enable(struct pmu *pmu)
{
u32 pmcr;
unsigned long flags;
struct dsu_pmu *dsu_pmu = to_dsu_pmu(pmu);
/* If no counters are added, skip enabling the PMU */
if (bitmap_empty(dsu_pmu->hw_events.used_mask, DSU_PMU_MAX_HW_CNTRS))
return;
raw_spin_lock_irqsave(&dsu_pmu->pmu_lock, flags);
pmcr = __dsu_pmu_read_pmcr();
pmcr |= CLUSTERPMCR_E;
__dsu_pmu_write_pmcr(pmcr);
raw_spin_unlock_irqrestore(&dsu_pmu->pmu_lock, flags);
}
static void dsu_pmu_disable(struct pmu *pmu)
{
u32 pmcr;
unsigned long flags;
struct dsu_pmu *dsu_pmu = to_dsu_pmu(pmu);
raw_spin_lock_irqsave(&dsu_pmu->pmu_lock, flags);
pmcr = __dsu_pmu_read_pmcr();
pmcr &= ~CLUSTERPMCR_E;
__dsu_pmu_write_pmcr(pmcr);
raw_spin_unlock_irqrestore(&dsu_pmu->pmu_lock, flags);
}
static bool dsu_pmu_validate_event(struct pmu *pmu,
struct dsu_hw_events *hw_events,
struct perf_event *event)
{
if (is_software_event(event))
return true;
/* Reject groups spanning multiple HW PMUs. */
if (event->pmu != pmu)
return false;
return dsu_pmu_get_event_idx(hw_events, event) >= 0;
}
/*
* Make sure the group of events can be scheduled at once
* on the PMU.
*/
static bool dsu_pmu_validate_group(struct perf_event *event)
{
struct perf_event *sibling, *leader = event->group_leader;
struct dsu_hw_events fake_hw;
if (event->group_leader == event)
return true;
memset(fake_hw.used_mask, 0, sizeof(fake_hw.used_mask));
if (!dsu_pmu_validate_event(event->pmu, &fake_hw, leader))
return false;
for_each_sibling_event(sibling, leader) {
if (!dsu_pmu_validate_event(event->pmu, &fake_hw, sibling))
return false;
}
return dsu_pmu_validate_event(event->pmu, &fake_hw, event);
}
static int dsu_pmu_event_init(struct perf_event *event)
{
struct dsu_pmu *dsu_pmu = to_dsu_pmu(event->pmu);
if (event->attr.type != event->pmu->type)
return -ENOENT;
/* We don't support sampling */
if (is_sampling_event(event)) {
dev_dbg(dsu_pmu->pmu.dev, "Can't support sampling events\n");
return -EOPNOTSUPP;
}
/* We cannot support task bound events */
if (event->cpu < 0 || event->attach_state & PERF_ATTACH_TASK) {
dev_dbg(dsu_pmu->pmu.dev, "Can't support per-task counters\n");
return -EINVAL;
}
if (has_branch_stack(event)) {
dev_dbg(dsu_pmu->pmu.dev, "Can't support filtering\n");
return -EINVAL;
}
if (!cpumask_test_cpu(event->cpu, &dsu_pmu->associated_cpus)) {
dev_dbg(dsu_pmu->pmu.dev,
"Requested cpu is not associated with the DSU\n");
return -EINVAL;
}
/*
* Choose the current active CPU to read the events. We don't want
* to migrate the event contexts, irq handling etc to the requested
* CPU. As long as the requested CPU is within the same DSU, we
* are fine.
*/
event->cpu = cpumask_first(&dsu_pmu->active_cpu);
if (event->cpu >= nr_cpu_ids)
return -EINVAL;
if (!dsu_pmu_validate_group(event))
return -EINVAL;
event->hw.config_base = event->attr.config;
return 0;
}
static struct dsu_pmu *dsu_pmu_alloc(struct platform_device *pdev)
{
struct dsu_pmu *dsu_pmu;
dsu_pmu = devm_kzalloc(&pdev->dev, sizeof(*dsu_pmu), GFP_KERNEL);
if (!dsu_pmu)
return ERR_PTR(-ENOMEM);
raw_spin_lock_init(&dsu_pmu->pmu_lock);
/*
* Initialise the number of counters to -1, until we probe
* the real number on a connected CPU.
*/
dsu_pmu->num_counters = -1;
return dsu_pmu;
}
/**
* dsu_pmu_dt_get_cpus: Get the list of CPUs in the cluster
* from device tree.
*/
static int dsu_pmu_dt_get_cpus(struct device *dev, cpumask_t *mask)
{
int i = 0, n, cpu;
struct device_node *cpu_node;
n = of_count_phandle_with_args(dev->of_node, "cpus", NULL);
if (n <= 0)
return -ENODEV;
for (; i < n; i++) {
cpu_node = of_parse_phandle(dev->of_node, "cpus", i);
if (!cpu_node)
break;
cpu = of_cpu_node_to_id(cpu_node);
of_node_put(cpu_node);
/*
* We have to ignore the failures here and continue scanning
* the list to handle cases where the nr_cpus could be capped
* in the running kernel.
*/
if (cpu < 0)
continue;
cpumask_set_cpu(cpu, mask);
}
return 0;
}
/**
* dsu_pmu_acpi_get_cpus: Get the list of CPUs in the cluster
* from ACPI.
*/
static int dsu_pmu_acpi_get_cpus(struct device *dev, cpumask_t *mask)
{
#ifdef CONFIG_ACPI
int cpu;
/*
* A dsu pmu node is inside a cluster parent node along with cpu nodes.
* We need to find out all cpus that have the same parent with this pmu.
*/
for_each_possible_cpu(cpu) {
struct acpi_device *acpi_dev;
struct device *cpu_dev = get_cpu_device(cpu);
if (!cpu_dev)
continue;
acpi_dev = ACPI_COMPANION(cpu_dev);
if (acpi_dev &&
acpi_dev->parent == ACPI_COMPANION(dev)->parent)
cpumask_set_cpu(cpu, mask);
}
#endif
return 0;
}
/*
* dsu_pmu_probe_pmu: Probe the PMU details on a CPU in the cluster.
*/
static void dsu_pmu_probe_pmu(struct dsu_pmu *dsu_pmu)
{
u64 num_counters;
u32 cpmceid[2];
num_counters = (__dsu_pmu_read_pmcr() >> CLUSTERPMCR_N_SHIFT) &
CLUSTERPMCR_N_MASK;
/* We can only support up to 31 independent counters */
if (WARN_ON(num_counters > 31))
num_counters = 31;
dsu_pmu->num_counters = num_counters;
if (!dsu_pmu->num_counters)
return;
cpmceid[0] = __dsu_pmu_read_pmceid(0);
cpmceid[1] = __dsu_pmu_read_pmceid(1);
bitmap_from_arr32(dsu_pmu->cpmceid_bitmap, cpmceid,
DSU_PMU_MAX_COMMON_EVENTS);
}
static void dsu_pmu_set_active_cpu(int cpu, struct dsu_pmu *dsu_pmu)
{
cpumask_set_cpu(cpu, &dsu_pmu->active_cpu);
if (irq_set_affinity(dsu_pmu->irq, &dsu_pmu->active_cpu))
pr_warn("Failed to set irq affinity to %d\n", cpu);
}
/*
* dsu_pmu_init_pmu: Initialise the DSU PMU configurations if
* we haven't done it already.
*/
static void dsu_pmu_init_pmu(struct dsu_pmu *dsu_pmu)
{
if (dsu_pmu->num_counters == -1)
dsu_pmu_probe_pmu(dsu_pmu);
/* Reset the interrupt overflow mask */
dsu_pmu_get_reset_overflow();
}
static int dsu_pmu_device_probe(struct platform_device *pdev)
{
int irq, rc;
struct dsu_pmu *dsu_pmu;
struct fwnode_handle *fwnode = dev_fwnode(&pdev->dev);
char *name;
static atomic_t pmu_idx = ATOMIC_INIT(-1);
dsu_pmu = dsu_pmu_alloc(pdev);
if (IS_ERR(dsu_pmu))
return PTR_ERR(dsu_pmu);
if (is_of_node(fwnode))
rc = dsu_pmu_dt_get_cpus(&pdev->dev, &dsu_pmu->associated_cpus);
else if (is_acpi_device_node(fwnode))
rc = dsu_pmu_acpi_get_cpus(&pdev->dev, &dsu_pmu->associated_cpus);
else
return -ENOENT;
if (rc) {
dev_warn(&pdev->dev, "Failed to parse the CPUs\n");
return rc;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return -EINVAL;
name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%s_%d",
PMUNAME, atomic_inc_return(&pmu_idx));
if (!name)
return -ENOMEM;
rc = devm_request_irq(&pdev->dev, irq, dsu_pmu_handle_irq,
IRQF_NOBALANCING, name, dsu_pmu);
if (rc) {
dev_warn(&pdev->dev, "Failed to request IRQ %d\n", irq);
return rc;
}
dsu_pmu->irq = irq;
platform_set_drvdata(pdev, dsu_pmu);
rc = cpuhp_state_add_instance(dsu_pmu_cpuhp_state,
&dsu_pmu->cpuhp_node);
if (rc)
return rc;
dsu_pmu->pmu = (struct pmu) {
.task_ctx_nr = perf_invalid_context,
.module = THIS_MODULE,
.pmu_enable = dsu_pmu_enable,
.pmu_disable = dsu_pmu_disable,
.event_init = dsu_pmu_event_init,
.add = dsu_pmu_add,
.del = dsu_pmu_del,
.start = dsu_pmu_start,
.stop = dsu_pmu_stop,
.read = dsu_pmu_read,
.attr_groups = dsu_pmu_attr_groups,
.capabilities = PERF_PMU_CAP_NO_EXCLUDE,
};
rc = perf_pmu_register(&dsu_pmu->pmu, name, -1);
if (rc) {
cpuhp_state_remove_instance(dsu_pmu_cpuhp_state,
&dsu_pmu->cpuhp_node);
}
return rc;
}
static int dsu_pmu_device_remove(struct platform_device *pdev)
{
struct dsu_pmu *dsu_pmu = platform_get_drvdata(pdev);
perf_pmu_unregister(&dsu_pmu->pmu);
cpuhp_state_remove_instance(dsu_pmu_cpuhp_state, &dsu_pmu->cpuhp_node);
return 0;
}
static const struct of_device_id dsu_pmu_of_match[] = {
{ .compatible = "arm,dsu-pmu", },
{},
};
MODULE_DEVICE_TABLE(of, dsu_pmu_of_match);
#ifdef CONFIG_ACPI
static const struct acpi_device_id dsu_pmu_acpi_match[] = {
{ "ARMHD500", 0},
{},
};
MODULE_DEVICE_TABLE(acpi, dsu_pmu_acpi_match);
#endif
static struct platform_driver dsu_pmu_driver = {
.driver = {
.name = DRVNAME,
.of_match_table = of_match_ptr(dsu_pmu_of_match),
.acpi_match_table = ACPI_PTR(dsu_pmu_acpi_match),
.suppress_bind_attrs = true,
},
.probe = dsu_pmu_device_probe,
.remove = dsu_pmu_device_remove,
};
static int dsu_pmu_cpu_online(unsigned int cpu, struct hlist_node *node)
{
struct dsu_pmu *dsu_pmu = hlist_entry_safe(node, struct dsu_pmu,
cpuhp_node);
if (!cpumask_test_cpu(cpu, &dsu_pmu->associated_cpus))
return 0;
/* If the PMU is already managed, there is nothing to do */
if (!cpumask_empty(&dsu_pmu->active_cpu))
return 0;
dsu_pmu_init_pmu(dsu_pmu);
dsu_pmu_set_active_cpu(cpu, dsu_pmu);
return 0;
}
static int dsu_pmu_cpu_teardown(unsigned int cpu, struct hlist_node *node)
{
int dst;
struct dsu_pmu *dsu_pmu = hlist_entry_safe(node, struct dsu_pmu,
cpuhp_node);
if (!cpumask_test_and_clear_cpu(cpu, &dsu_pmu->active_cpu))
return 0;
dst = dsu_pmu_get_online_cpu_any_but(dsu_pmu, cpu);
/* If there are no active CPUs in the DSU, leave IRQ disabled */
if (dst >= nr_cpu_ids)
return 0;
perf_pmu_migrate_context(&dsu_pmu->pmu, cpu, dst);
dsu_pmu_set_active_cpu(dst, dsu_pmu);
return 0;
}
static int __init dsu_pmu_init(void)
{
int ret;
ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
DRVNAME,
dsu_pmu_cpu_online,
dsu_pmu_cpu_teardown);
if (ret < 0)
return ret;
dsu_pmu_cpuhp_state = ret;
return platform_driver_register(&dsu_pmu_driver);
}
static void __exit dsu_pmu_exit(void)
{
platform_driver_unregister(&dsu_pmu_driver);
cpuhp_remove_multi_state(dsu_pmu_cpuhp_state);
}
module_init(dsu_pmu_init);
module_exit(dsu_pmu_exit);
MODULE_DESCRIPTION("Perf driver for ARM DynamIQ Shared Unit");
MODULE_AUTHOR("Suzuki K Poulose <suzuki.poulose@arm.com>");
MODULE_LICENSE("GPL v2");