/*
* Driver for the L3 cache PMUs in Qualcomm Technologies chips.
*
* The driver supports a distributed cache architecture where the overall
* cache for a socket is comprised of multiple slices each with its own PMU.
* Access to each individual PMU is provided even though all CPUs share all
* the slices. User space needs to aggregate to individual counts to provide
* a global picture.
*
* See Documentation/perf/qcom_l3_pmu.txt for more details.
*
* Copyright (c) 2015-2017, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/acpi.h>
#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/perf_event.h>
#include <linux/platform_device.h>
/*
* General constants
*/
/* Number of counters on each PMU */
#define L3_NUM_COUNTERS 8
/* Mask for the event type field within perf_event_attr.config and EVTYPE reg */
#define L3_EVTYPE_MASK 0xFF
/*
* Bit position of the 'long counter' flag within perf_event_attr.config.
* Reserve some space between the event type and this flag to allow expansion
* in the event type field.
*/
#define L3_EVENT_LC_BIT 32
/*
* Register offsets
*/
/* Perfmon registers */
#define L3_HML3_PM_CR 0x000
#define L3_HML3_PM_EVCNTR(__cntr) (0x420 + ((__cntr) & 0x7) * 8)
#define L3_HML3_PM_CNTCTL(__cntr) (0x120 + ((__cntr) & 0x7) * 8)
#define L3_HML3_PM_EVTYPE(__cntr) (0x220 + ((__cntr) & 0x7) * 8)
#define L3_HML3_PM_FILTRA 0x300
#define L3_HML3_PM_FILTRB 0x308
#define L3_HML3_PM_FILTRC 0x310
#define L3_HML3_PM_FILTRAM 0x304
#define L3_HML3_PM_FILTRBM 0x30C
#define L3_HML3_PM_FILTRCM 0x314
/* Basic counter registers */
#define L3_M_BC_CR 0x500
#define L3_M_BC_SATROLL_CR 0x504
#define L3_M_BC_CNTENSET 0x508
#define L3_M_BC_CNTENCLR 0x50C
#define L3_M_BC_INTENSET 0x510
#define L3_M_BC_INTENCLR 0x514
#define L3_M_BC_GANG 0x718
#define L3_M_BC_OVSR 0x740
#define L3_M_BC_IRQCTL 0x96C
/*
* Bit field definitions
*/
/* L3_HML3_PM_CR */
#define PM_CR_RESET (0)
/* L3_HML3_PM_XCNTCTL/L3_HML3_PM_CNTCTLx */
#define PMCNT_RESET (0)
/* L3_HML3_PM_EVTYPEx */
#define EVSEL(__val) ((__val) & L3_EVTYPE_MASK)
/* Reset value for all the filter registers */
#define PM_FLTR_RESET (0)
/* L3_M_BC_CR */
#define BC_RESET (1UL << 1)
#define BC_ENABLE (1UL << 0)
/* L3_M_BC_SATROLL_CR */
#define BC_SATROLL_CR_RESET (0)
/* L3_M_BC_CNTENSET */
#define PMCNTENSET(__cntr) (1UL << ((__cntr) & 0x7))
/* L3_M_BC_CNTENCLR */
#define PMCNTENCLR(__cntr) (1UL << ((__cntr) & 0x7))
#define BC_CNTENCLR_RESET (0xFF)
/* L3_M_BC_INTENSET */
#define PMINTENSET(__cntr) (1UL << ((__cntr) & 0x7))
/* L3_M_BC_INTENCLR */
#define PMINTENCLR(__cntr) (1UL << ((__cntr) & 0x7))
#define BC_INTENCLR_RESET (0xFF)
/* L3_M_BC_GANG */
#define GANG_EN(__cntr) (1UL << ((__cntr) & 0x7))
#define BC_GANG_RESET (0)
/* L3_M_BC_OVSR */
#define PMOVSRCLR(__cntr) (1UL << ((__cntr) & 0x7))
#define PMOVSRCLR_RESET (0xFF)
/* L3_M_BC_IRQCTL */
#define PMIRQONMSBEN(__cntr) (1UL << ((__cntr) & 0x7))
#define BC_IRQCTL_RESET (0x0)
/*
* Events
*/
#define L3_EVENT_CYCLES 0x01
#define L3_EVENT_READ_HIT 0x20
#define L3_EVENT_READ_MISS 0x21
#define L3_EVENT_READ_HIT_D 0x22
#define L3_EVENT_READ_MISS_D 0x23
#define L3_EVENT_WRITE_HIT 0x24
#define L3_EVENT_WRITE_MISS 0x25
/*
* Decoding of settings from perf_event_attr
*
* The config format for perf events is:
* - config: bits 0-7: event type
* bit 32: HW counter size requested, 0: 32 bits, 1: 64 bits
*/
static inline u32 get_event_type(struct perf_event *event)
{
return (event->attr.config) & L3_EVTYPE_MASK;
}
static inline bool event_uses_long_counter(struct perf_event *event)
{
return !!(event->attr.config & BIT_ULL(L3_EVENT_LC_BIT));
}
static inline int event_num_counters(struct perf_event *event)
{
return event_uses_long_counter(event) ? 2 : 1;
}
/*
* Main PMU, inherits from the core perf PMU type
*/
struct l3cache_pmu {
struct pmu pmu;
struct hlist_node node;
void __iomem *regs;
struct perf_event *events[L3_NUM_COUNTERS];
unsigned long used_mask[BITS_TO_LONGS(L3_NUM_COUNTERS)];
cpumask_t cpumask;
};
#define to_l3cache_pmu(p) (container_of(p, struct l3cache_pmu, pmu))
/*
* Type used to group hardware counter operations
*
* Used to implement two types of hardware counters, standard (32bits) and
* long (64bits). The hardware supports counter chaining which we use to
* implement long counters. This support is exposed via the 'lc' flag field
* in perf_event_attr.config.
*/
struct l3cache_event_ops {
/* Called to start event monitoring */
void (*start)(struct perf_event *event);
/* Called to stop event monitoring */
void (*stop)(struct perf_event *event, int flags);
/* Called to update the perf_event */
void (*update)(struct perf_event *event);
};
/*
* Implementation of long counter operations
*
* 64bit counters are implemented by chaining two of the 32bit physical
* counters. The PMU only supports chaining of adjacent even/odd pairs
* and for simplicity the driver always configures the odd counter to
* count the overflows of the lower-numbered even counter. Note that since
* the resulting hardware counter is 64bits no IRQs are required to maintain
* the software counter which is also 64bits.
*/
static void qcom_l3_cache__64bit_counter_start(struct perf_event *event)
{
struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
int idx = event->hw.idx;
u32 evsel = get_event_type(event);
u32 gang;
/* Set the odd counter to count the overflows of the even counter */
gang = readl_relaxed(l3pmu->regs + L3_M_BC_GANG);
gang |= GANG_EN(idx + 1);
writel_relaxed(gang, l3pmu->regs + L3_M_BC_GANG);
/* Initialize the hardware counters and reset prev_count*/
local64_set(&event->hw.prev_count, 0);
writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1));
writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx));
/*
* Set the event types, the upper half must use zero and the lower
* half the actual event type
*/
writel_relaxed(EVSEL(0), l3pmu->regs + L3_HML3_PM_EVTYPE(idx + 1));
writel_relaxed(EVSEL(evsel), l3pmu->regs + L3_HML3_PM_EVTYPE(idx));
/* Finally, enable the counters */
writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx + 1));
writel_relaxed(PMCNTENSET(idx + 1), l3pmu->regs + L3_M_BC_CNTENSET);
writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx));
writel_relaxed(PMCNTENSET(idx), l3pmu->regs + L3_M_BC_CNTENSET);
}
static void qcom_l3_cache__64bit_counter_stop(struct perf_event *event,
int flags)
{
struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
int idx = event->hw.idx;
u32 gang = readl_relaxed(l3pmu->regs + L3_M_BC_GANG);
/* Disable the counters */
writel_relaxed(PMCNTENCLR(idx), l3pmu->regs + L3_M_BC_CNTENCLR);
writel_relaxed(PMCNTENCLR(idx + 1), l3pmu->regs + L3_M_BC_CNTENCLR);
/* Disable chaining */
writel_relaxed(gang & ~GANG_EN(idx + 1), l3pmu->regs + L3_M_BC_GANG);
}
static void qcom_l3_cache__64bit_counter_update(struct perf_event *event)
{
struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
int idx = event->hw.idx;
u32 hi, lo;
u64 prev, new;
do {
prev = local64_read(&event->hw.prev_count);
do {
hi = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1));
lo = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx));
} while (hi != readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1)));
new = ((u64)hi << 32) | lo;
} while (local64_cmpxchg(&event->hw.prev_count, prev, new) != prev);
local64_add(new - prev, &event->count);
}
static const struct l3cache_event_ops event_ops_long = {
.start = qcom_l3_cache__64bit_counter_start,
.stop = qcom_l3_cache__64bit_counter_stop,
.update = qcom_l3_cache__64bit_counter_update,
};
/*
* Implementation of standard counter operations
*
* 32bit counters use a single physical counter and a hardware feature that
* asserts the overflow IRQ on the toggling of the most significant bit in
* the counter. This feature allows the counters to be left free-running
* without needing the usual reprogramming required to properly handle races
* during concurrent calls to update.
*/
static void qcom_l3_cache__32bit_counter_start(struct perf_event *event)
{
struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
int idx = event->hw.idx;
u32 evsel = get_event_type(event);
u32 irqctl = readl_relaxed(l3pmu->regs + L3_M_BC_IRQCTL);
/* Set the counter to assert the overflow IRQ on MSB toggling */
writel_relaxed(irqctl | PMIRQONMSBEN(idx), l3pmu->regs + L3_M_BC_IRQCTL);
/* Initialize the hardware counter and reset prev_count*/
local64_set(&event->hw.prev_count, 0);
writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx));
/* Set the event type */
writel_relaxed(EVSEL(evsel), l3pmu->regs + L3_HML3_PM_EVTYPE(idx));
/* Enable interrupt generation by this counter */
writel_relaxed(PMINTENSET(idx), l3pmu->regs + L3_M_BC_INTENSET);
/* Finally, enable the counter */
writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx));
writel_relaxed(PMCNTENSET(idx), l3pmu->regs + L3_M_BC_CNTENSET);
}
static void qcom_l3_cache__32bit_counter_stop(struct perf_event *event,
int flags)
{
struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
int idx = event->hw.idx;
u32 irqctl = readl_relaxed(l3pmu->regs + L3_M_BC_IRQCTL);
/* Disable the counter */
writel_relaxed(PMCNTENCLR(idx), l3pmu->regs + L3_M_BC_CNTENCLR);
/* Disable interrupt generation by this counter */
writel_relaxed(PMINTENCLR(idx), l3pmu->regs + L3_M_BC_INTENCLR);
/* Set the counter to not assert the overflow IRQ on MSB toggling */
writel_relaxed(irqctl & ~PMIRQONMSBEN(idx), l3pmu->regs + L3_M_BC_IRQCTL);
}
static void qcom_l3_cache__32bit_counter_update(struct perf_event *event)
{
struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
int idx = event->hw.idx;
u32 prev, new;
do {
prev = local64_read(&event->hw.prev_count);
new = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx));
} while (local64_cmpxchg(&event->hw.prev_count, prev, new) != prev);
local64_add(new - prev, &event->count);
}
static const struct l3cache_event_ops event_ops_std = {
.start = qcom_l3_cache__32bit_counter_start,
.stop = qcom_l3_cache__32bit_counter_stop,
.update = qcom_l3_cache__32bit_counter_update,
};
/* Retrieve the appropriate operations for the given event */
static
const struct l3cache_event_ops *l3cache_event_get_ops(struct perf_event *event)
{
if (event_uses_long_counter(event))
return &event_ops_long;
else
return &event_ops_std;
}
/*
* Top level PMU functions.
*/
static inline void qcom_l3_cache__init(struct l3cache_pmu *l3pmu)
{
int i;
writel_relaxed(BC_RESET, l3pmu->regs + L3_M_BC_CR);
/*
* Use writel for the first programming command to ensure the basic
* counter unit is stopped before proceeding
*/
writel(BC_SATROLL_CR_RESET, l3pmu->regs + L3_M_BC_SATROLL_CR);
writel_relaxed(BC_CNTENCLR_RESET, l3pmu->regs + L3_M_BC_CNTENCLR);
writel_relaxed(BC_INTENCLR_RESET, l3pmu->regs + L3_M_BC_INTENCLR);
writel_relaxed(PMOVSRCLR_RESET, l3pmu->regs + L3_M_BC_OVSR);
writel_relaxed(BC_GANG_RESET, l3pmu->regs + L3_M_BC_GANG);
writel_relaxed(BC_IRQCTL_RESET, l3pmu->regs + L3_M_BC_IRQCTL);
writel_relaxed(PM_CR_RESET, l3pmu->regs + L3_HML3_PM_CR);
for (i = 0; i < L3_NUM_COUNTERS; ++i) {
writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(i));
writel_relaxed(EVSEL(0), l3pmu->regs + L3_HML3_PM_EVTYPE(i));
}
writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRA);
writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRAM);
writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRB);
writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRBM);
writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRC);
writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRCM);
/*
* Use writel here to ensure all programming commands are done
* before proceeding
*/
writel(BC_ENABLE, l3pmu->regs + L3_M_BC_CR);
}
static irqreturn_t qcom_l3_cache__handle_irq(int irq_num, void *data)
{
struct l3cache_pmu *l3pmu = data;
/* Read the overflow status register */
long status = readl_relaxed(l3pmu->regs + L3_M_BC_OVSR);
int idx;
if (status == 0)
return IRQ_NONE;
/* Clear the bits we read on the overflow status register */
writel_relaxed(status, l3pmu->regs + L3_M_BC_OVSR);
for_each_set_bit(idx, &status, L3_NUM_COUNTERS) {
struct perf_event *event;
const struct l3cache_event_ops *ops;
event = l3pmu->events[idx];
if (!event)
continue;
/*
* Since the IRQ is not enabled for events using long counters
* we should never see one of those here, however, be consistent
* and use the ops indirections like in the other operations.
*/
ops = l3cache_event_get_ops(event);
ops->update(event);
}
return IRQ_HANDLED;
}
/*
* Implementation of abstract pmu functionality required by
* the core perf events code.
*/
static void qcom_l3_cache__pmu_enable(struct pmu *pmu)
{
struct l3cache_pmu *l3pmu = to_l3cache_pmu(pmu);
/* Ensure the other programming commands are observed before enabling */
wmb();
writel_relaxed(BC_ENABLE, l3pmu->regs + L3_M_BC_CR);
}
static void qcom_l3_cache__pmu_disable(struct pmu *pmu)
{
struct l3cache_pmu *l3pmu = to_l3cache_pmu(pmu);
writel_relaxed(0, l3pmu->regs + L3_M_BC_CR);
/* Ensure the basic counter unit is stopped before proceeding */
wmb();
}
/*
* We must NOT create groups containing events from multiple hardware PMUs,
* although mixing different software and hardware PMUs is allowed.
*/
static bool qcom_l3_cache__validate_event_group(struct perf_event *event)
{
struct perf_event *leader = event->group_leader;
struct perf_event *sibling;
int counters = 0;
if (leader->pmu != event->pmu && !is_software_event(leader))
return false;
counters = event_num_counters(event);
counters += event_num_counters(leader);
for_each_sibling_event(sibling, leader) {
if (is_software_event(sibling))
continue;
if (sibling->pmu != event->pmu)
return false;
counters += event_num_counters(sibling);
}
/*
* If the group requires more counters than the HW has, it
* cannot ever be scheduled.
*/
return counters <= L3_NUM_COUNTERS;
}
static int qcom_l3_cache__event_init(struct perf_event *event)
{
struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
/*
* Is the event for this PMU?
*/
if (event->attr.type != event->pmu->type)
return -ENOENT;
/*
* There are no per-counter mode filters in the PMU.
*/
if (event->attr.exclude_user || event->attr.exclude_kernel ||
event->attr.exclude_hv || event->attr.exclude_idle)
return -EINVAL;
/*
* Sampling not supported since these events are not core-attributable.
*/
if (hwc->sample_period)
return -EINVAL;
/*
* Task mode not available, we run the counters as socket counters,
* not attributable to any CPU and therefore cannot attribute per-task.
*/
if (event->cpu < 0)
return -EINVAL;
/* Validate the group */
if (!qcom_l3_cache__validate_event_group(event))
return -EINVAL;
hwc->idx = -1;
/*
* Many perf core operations (eg. events rotation) operate on a
* single CPU context. This is obvious for CPU PMUs, where one
* expects the same sets of events being observed on all CPUs,
* but can lead to issues for off-core PMUs, like this one, where
* each event could be theoretically assigned to a different CPU.
* To mitigate this, we enforce CPU assignment to one designated
* processor (the one described in the "cpumask" attribute exported
* by the PMU device). perf user space tools honor this and avoid
* opening more than one copy of the events.
*/
event->cpu = cpumask_first(&l3pmu->cpumask);
return 0;
}
static void qcom_l3_cache__event_start(struct perf_event *event, int flags)
{
struct hw_perf_event *hwc = &event->hw;
const struct l3cache_event_ops *ops = l3cache_event_get_ops(event);
hwc->state = 0;
ops->start(event);
}
static void qcom_l3_cache__event_stop(struct perf_event *event, int flags)
{
struct hw_perf_event *hwc = &event->hw;
const struct l3cache_event_ops *ops = l3cache_event_get_ops(event);
if (hwc->state & PERF_HES_STOPPED)
return;
ops->stop(event, flags);
if (flags & PERF_EF_UPDATE)
ops->update(event);
hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
}
static int qcom_l3_cache__event_add(struct perf_event *event, int flags)
{
struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
int order = event_uses_long_counter(event) ? 1 : 0;
int idx;
/*
* Try to allocate a counter.
*/
idx = bitmap_find_free_region(l3pmu->used_mask, L3_NUM_COUNTERS, order);
if (idx < 0)
/* The counters are all in use. */
return -EAGAIN;
hwc->idx = idx;
hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
l3pmu->events[idx] = event;
if (flags & PERF_EF_START)
qcom_l3_cache__event_start(event, 0);
/* Propagate changes to the userspace mapping. */
perf_event_update_userpage(event);
return 0;
}
static void qcom_l3_cache__event_del(struct perf_event *event, int flags)
{
struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
struct hw_perf_event *hwc = &event->hw;
int order = event_uses_long_counter(event) ? 1 : 0;
/* Stop and clean up */
qcom_l3_cache__event_stop(event, flags | PERF_EF_UPDATE);
l3pmu->events[hwc->idx] = NULL;
bitmap_release_region(l3pmu->used_mask, hwc->idx, order);
/* Propagate changes to the userspace mapping. */
perf_event_update_userpage(event);
}
static void qcom_l3_cache__event_read(struct perf_event *event)
{
const struct l3cache_event_ops *ops = l3cache_event_get_ops(event);
ops->update(event);
}
/*
* Add sysfs attributes
*
* We export:
* - formats, used by perf user space and other tools to configure events
* - events, used by perf user space and other tools to create events
* symbolically, e.g.:
* perf stat -a -e l3cache_0_0/event=read-miss/ ls
* perf stat -a -e l3cache_0_0/event=0x21/ ls
* - cpumask, used by perf user space and other tools to know on which CPUs
* to open the events
*/
/* formats */
static ssize_t l3cache_pmu_format_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct dev_ext_attribute *eattr;
eattr = container_of(attr, struct dev_ext_attribute, attr);
return sprintf(buf, "%s\n", (char *) eattr->var);
}
#define L3CACHE_PMU_FORMAT_ATTR(_name, _config) \
(&((struct dev_ext_attribute[]) { \
{ .attr = __ATTR(_name, 0444, l3cache_pmu_format_show, NULL), \
.var = (void *) _config, } \
})[0].attr.attr)
static struct attribute *qcom_l3_cache_pmu_formats[] = {
L3CACHE_PMU_FORMAT_ATTR(event, "config:0-7"),
L3CACHE_PMU_FORMAT_ATTR(lc, "config:" __stringify(L3_EVENT_LC_BIT)),
NULL,
};
static struct attribute_group qcom_l3_cache_pmu_format_group = {
.name = "format",
.attrs = qcom_l3_cache_pmu_formats,
};
/* events */
static ssize_t l3cache_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 sprintf(page, "event=0x%02llx\n", pmu_attr->id);
}
#define L3CACHE_EVENT_ATTR(_name, _id) \
(&((struct perf_pmu_events_attr[]) { \
{ .attr = __ATTR(_name, 0444, l3cache_pmu_event_show, NULL), \
.id = _id, } \
})[0].attr.attr)
static struct attribute *qcom_l3_cache_pmu_events[] = {
L3CACHE_EVENT_ATTR(cycles, L3_EVENT_CYCLES),
L3CACHE_EVENT_ATTR(read-hit, L3_EVENT_READ_HIT),
L3CACHE_EVENT_ATTR(read-miss, L3_EVENT_READ_MISS),
L3CACHE_EVENT_ATTR(read-hit-d-side, L3_EVENT_READ_HIT_D),
L3CACHE_EVENT_ATTR(read-miss-d-side, L3_EVENT_READ_MISS_D),
L3CACHE_EVENT_ATTR(write-hit, L3_EVENT_WRITE_HIT),
L3CACHE_EVENT_ATTR(write-miss, L3_EVENT_WRITE_MISS),
NULL
};
static struct attribute_group qcom_l3_cache_pmu_events_group = {
.name = "events",
.attrs = qcom_l3_cache_pmu_events,
};
/* cpumask */
static ssize_t qcom_l3_cache_pmu_cpumask_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct l3cache_pmu *l3pmu = to_l3cache_pmu(dev_get_drvdata(dev));
return cpumap_print_to_pagebuf(true, buf, &l3pmu->cpumask);
}
static DEVICE_ATTR(cpumask, 0444, qcom_l3_cache_pmu_cpumask_show, NULL);
static struct attribute *qcom_l3_cache_pmu_cpumask_attrs[] = {
&dev_attr_cpumask.attr,
NULL,
};
static struct attribute_group qcom_l3_cache_pmu_cpumask_attr_group = {
.attrs = qcom_l3_cache_pmu_cpumask_attrs,
};
/*
* Per PMU device attribute groups
*/
static const struct attribute_group *qcom_l3_cache_pmu_attr_grps[] = {
&qcom_l3_cache_pmu_format_group,
&qcom_l3_cache_pmu_events_group,
&qcom_l3_cache_pmu_cpumask_attr_group,
NULL,
};
/*
* Probing functions and data.
*/
static int qcom_l3_cache_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)
{
struct l3cache_pmu *l3pmu = hlist_entry_safe(node, struct l3cache_pmu, node);
/* If there is not a CPU/PMU association pick this CPU */
if (cpumask_empty(&l3pmu->cpumask))
cpumask_set_cpu(cpu, &l3pmu->cpumask);
return 0;
}
static int qcom_l3_cache_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
{
struct l3cache_pmu *l3pmu = hlist_entry_safe(node, struct l3cache_pmu, node);
unsigned int target;
if (!cpumask_test_and_clear_cpu(cpu, &l3pmu->cpumask))
return 0;
target = cpumask_any_but(cpu_online_mask, cpu);
if (target >= nr_cpu_ids)
return 0;
perf_pmu_migrate_context(&l3pmu->pmu, cpu, target);
cpumask_set_cpu(target, &l3pmu->cpumask);
return 0;
}
static int qcom_l3_cache_pmu_probe(struct platform_device *pdev)
{
struct l3cache_pmu *l3pmu;
struct acpi_device *acpi_dev;
struct resource *memrc;
int ret;
char *name;
/* Initialize the PMU data structures */
acpi_dev = ACPI_COMPANION(&pdev->dev);
if (!acpi_dev)
return -ENODEV;
l3pmu = devm_kzalloc(&pdev->dev, sizeof(*l3pmu), GFP_KERNEL);
name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "l3cache_%s_%s",
acpi_dev->parent->pnp.unique_id, acpi_dev->pnp.unique_id);
if (!l3pmu || !name)
return -ENOMEM;
l3pmu->pmu = (struct pmu) {
.task_ctx_nr = perf_invalid_context,
.pmu_enable = qcom_l3_cache__pmu_enable,
.pmu_disable = qcom_l3_cache__pmu_disable,
.event_init = qcom_l3_cache__event_init,
.add = qcom_l3_cache__event_add,
.del = qcom_l3_cache__event_del,
.start = qcom_l3_cache__event_start,
.stop = qcom_l3_cache__event_stop,
.read = qcom_l3_cache__event_read,
.attr_groups = qcom_l3_cache_pmu_attr_grps,
};
memrc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
l3pmu->regs = devm_ioremap_resource(&pdev->dev, memrc);
if (IS_ERR(l3pmu->regs)) {
dev_err(&pdev->dev, "Can't map PMU @%pa\n", &memrc->start);
return PTR_ERR(l3pmu->regs);
}
qcom_l3_cache__init(l3pmu);
ret = platform_get_irq(pdev, 0);
if (ret <= 0)
return ret;
ret = devm_request_irq(&pdev->dev, ret, qcom_l3_cache__handle_irq, 0,
name, l3pmu);
if (ret) {
dev_err(&pdev->dev, "Request for IRQ failed for slice @%pa\n",
&memrc->start);
return ret;
}
/* Add this instance to the list used by the offline callback */
ret = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE, &l3pmu->node);
if (ret) {
dev_err(&pdev->dev, "Error %d registering hotplug", ret);
return ret;
}
ret = perf_pmu_register(&l3pmu->pmu, name, -1);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to register L3 cache PMU (%d)\n", ret);
return ret;
}
dev_info(&pdev->dev, "Registered %s, type: %d\n", name, l3pmu->pmu.type);
return 0;
}
static const struct acpi_device_id qcom_l3_cache_pmu_acpi_match[] = {
{ "QCOM8081", },
{ }
};
MODULE_DEVICE_TABLE(acpi, qcom_l3_cache_pmu_acpi_match);
static struct platform_driver qcom_l3_cache_pmu_driver = {
.driver = {
.name = "qcom-l3cache-pmu",
.acpi_match_table = ACPI_PTR(qcom_l3_cache_pmu_acpi_match),
},
.probe = qcom_l3_cache_pmu_probe,
};
static int __init register_qcom_l3_cache_pmu_driver(void)
{
int ret;
/* Install a hook to update the reader CPU in case it goes offline */
ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE,
"perf/qcom/l3cache:online",
qcom_l3_cache_pmu_online_cpu,
qcom_l3_cache_pmu_offline_cpu);
if (ret)
return ret;
return platform_driver_register(&qcom_l3_cache_pmu_driver);
}
device_initcall(register_qcom_l3_cache_pmu_driver);
