Re: [PATCH] driver/perf: Add PMU driver for the ARM DMC-620 memory controller.

From: Tuan Phan
Date: Wed Mar 18 2020 - 23:01:57 EST


Hi Shaokun,
Please find my comments below.

> On Mar 18, 2020, at 6:34 PM, Shaokun Zhang <zhangshaokun@xxxxxxxxxxxxx> wrote:
>
> Hi Tuan,
>
> On 2020/3/18 8:29, Tuan Phan wrote:
>> DMC-620 PMU supports total 10 counters which each is
>> independently programmable to different events and can
>> be started and stopped individually.
>>
>> DMC-620 PMU devices are named as arm_dmc620_<uid> where
>> <uid> is the UID of DMC-620 PMU ACPI node. Currently, it only
>> supports ACPI. Other platforms feel free to test and add
>> support for device tree.
>>
>> Usage example:
>> #perf stat -e arm_dmc620_0/clk_cycle_count/ -C 0
>> Get perf event for clk_cycle_count counter.
>>
>> #perf stat -e arm_dmc620_0/clkdiv2_allocate,mask=0x1f,match=0x2f,
>> incr=2,invert=1/ -C 0
>> The above example shows how to specify mask, match, incr,
>> invert parameters for clkdiv2_allocate event.
>>
>> Signed-off-by: Tuan Phan <tuanphan@xxxxxxxxxxxxxxxxxxxxxx>
>> ---
>> drivers/perf/Kconfig | 8 +
>> drivers/perf/Makefile | 1 +
>> drivers/perf/arm_dmc620_pmu.c | 836 ++++++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 845 insertions(+)
>> create mode 100644 drivers/perf/arm_dmc620_pmu.c
>>
>> diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig
>> index 09ae8a9..8c5b5cf 100644
>> --- a/drivers/perf/Kconfig
>> +++ b/drivers/perf/Kconfig
>> @@ -129,4 +129,12 @@ config ARM_SPE_PMU
>> Extension, which provides periodic sampling of operations in
>> the CPU pipeline and reports this via the perf AUX interface.
>>
>> +config ARM_DMC620_PMU
>> + bool "Enable PMU support for the ARM DMC-620 memory controller"
>> + depends on ARM64 && ACPI
>> + default n
>> + help
>> + Support for PMU events monitoring on the ARM DMC-620 memory
>> + controller.
>> +
>> endmenu
>> diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile
>> index 2ebb4de..15a31ac 100644
>> --- a/drivers/perf/Makefile
>> +++ b/drivers/perf/Makefile
>> @@ -12,3 +12,4 @@ obj-$(CONFIG_QCOM_L3_PMU) += qcom_l3_pmu.o
>> obj-$(CONFIG_THUNDERX2_PMU) += thunderx2_pmu.o
>> obj-$(CONFIG_XGENE_PMU) += xgene_pmu.o
>> obj-$(CONFIG_ARM_SPE_PMU) += arm_spe_pmu.o
>> +obj-$(CONFIG_ARM_DMC_PMU) += arm_dmc_pmu.o
>> \ No newline at end of file
>> diff --git a/drivers/perf/arm_dmc620_pmu.c b/drivers/perf/arm_dmc620_pmu.c
>> new file mode 100644
>> index 0000000..e222bdb
>> --- /dev/null
>> +++ b/drivers/perf/arm_dmc620_pmu.c
>> @@ -0,0 +1,836 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * ARM DMC-620 memory controller PMU driver
>> + *
>> + * Copyright (C) 2020 Ampere Computing LLC.
>> + */
>> +
>> +#define PMUNAME "arm_dmc620"
>> +#define DRVNAME PMUNAME "_pmu"
>> +#define pr_fmt(fmt) DRVNAME ": " fmt
>> +
>> +#include <linux/acpi.h>
>> +#include <linux/bitops.h>
>> +#include <linux/cpuhotplug.h>
>> +#include <linux/cpumask.h>
>> +#include <linux/device.h>
>> +#include <linux/errno.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/irq.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/perf_event.h>
>> +#include <linux/perf/arm_pmu.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/printk.h>
>> +
>> +#define DMC620_CNT_MAX_PERIOD 0xffffffff
>> +#define DMC620_PMU_CLKDIV2_MAX_COUNTERS 8
>> +#define DMC620_PMU_CLK_MAX_COUNTERS 2
>> +#define DMC620_PMU_MAX_COUNTERS \
>> + (DMC620_PMU_CLKDIV2_MAX_COUNTERS + DMC620_PMU_CLK_MAX_COUNTERS)
>> +
>> +#define DMC620_PMU_OVERFLOW_STATUS_CLKDIV2_OFFSET 8
>> +#define DMC620_PMU_OVERFLOW_STATUS_CLKDIV2_MASK \
>> + (DMC620_PMU_CLKDIV2_MAX_COUNTERS - 1)
>> +#define DMC620_PMU_OVERFLOW_STATUS_CLK_OFFSET 12
>> +#define DMC620_PMU_OVERFLOW_STATUS_CLK_MASK \
>> + (DMC620_PMU_CLK_MAX_COUNTERS - 1)
>> +#define DMC620_PMU_COUNTERS_BASE_OFFSET 16
>> +#define DMC620_PMU_COUNTER_MASK_31_00_OFFSET 0
>> +#define DMC620_PMU_COUNTER_MASK_63_32_OFFSET 4
>> +#define DMC620_PMU_COUNTER_MATCH_31_00_OFFSET 8
>> +#define DMC620_PMU_COUNTER_MATCH_63_32_OFFSET 12
>> +#define DMC620_PMU_COUNTER_CONTROL_OFFSET 16
>> +#define DMC620_PMU_COUNTER_CONTROL_ENABLE_MASK BIT(0)
>> +#define DMC620_PMU_COUNTER_CONTROL_INVERT_SHIFT 1
>> +#define DMC620_PMU_COUNTER_CONTROL_EVENT_MUX (((x)&0x1f)>>2)
>> +#define DMC620_PMU_COUNTER_CONTROL_EVENT_MUX_SHIFT 2
>> +#define DMC620_PMU_COUNTER_CONTROL_INCR (((x)&0x1ff)>>7)
>> +#define DMC620_PMU_COUNTER_CONTROL_INCR_SHIFT 7
>> +#define DMC620_PMU_COUNTER_SNAPSHOT_OFFSET 24
>> +#define DMC620_PMU_COUNTER_VALUE_OFFSET 32
>> +#define DMC620_PMU_COUNTER_REG_BYTE_LENGTH 40
>> +
>> +#define DMC620_PMU_CLKDIV2_CYCLE_COUNT 0x0
>> +#define DMC620_PMU_CLKDIV2_ALLOCATE 0x1
>> +#define DMC620_PMU_CLKDIV2_QUEUE_DEPTH 0x2
>> +#define DMC620_PMU_CLKDIV2_WAITING_FOR_WR_DATA 0x3
>> +#define DMC620_PMU_CLKDIV2_READ_BACKLOG 0x4
>> +#define DMC620_PMU_CLKDIV2_WAITING_FOR_MI 0x5
>> +#define DMC620_PMU_CLKDIV2_HAZARD_RESOLUTION 0x6
>> +#define DMC620_PMU_CLKDIV2_ENQUEUE 0x7
>> +#define DMC620_PMU_CLKDIV2_ARBITRATE 0x8
>> +#define DMC620_PMU_CLKDIV2_LRANK_TURNAROUND_ACTIVATE 0x9
>> +#define DMC620_PMU_CLKDIV2_PRANK_TURNAROUND_ACTIVATE 0xA
>> +#define DMC620_PMU_CLKDIV2_READ_DEPTH 0xB
>> +#define DMC620_PMU_CLKDIV2_WRITE_DEPTH 0xC
>> +#define DMC620_PMU_CLKDIV2_HIGHHIGH_QOS_DEPTH 0xD
>> +#define DMC620_PMU_CLKDIV2_HIGH_QOS_DEPTH 0xE
>> +#define DMC620_PMU_CLKDIV2_MEDIUM_QOS_DEPTH 0xF
>> +#define DMC620_PMU_CLKDIV2_LOW_QOS_DEPTH 0x10
>> +#define DMC620_PMU_CLKDIV2_ACTIVATE 0x11
>> +#define DMC620_PMU_CLKDIV2_RDWR 0x12
>> +#define DMC620_PMU_CLKDIV2_REFRESH 0x13
>> +#define DMC620_PMU_CLKDIV2_TRAINING_REQUEST 0x14
>> +#define DMC620_PMU_CLKDIV2_T_MAC_TRACKER 0x15
>> +#define DMC620_PMU_CLKDIV2_BK_FSM_TRACKER 0x16
>> +#define DMC620_PMU_CLKDIV2_BK_OPEN_TRACKER 0x17
>> +#define DMC620_PMU_CLKDIV2_RANKS_IN_PWR_DOWN 0x18
>> +#define DMC620_PMU_CLKDIV2_RANKS_IN_SREF 0x19
>> +
>> +#define DMC620_PMU_CLK_CYCLE_COUNTER 0x20
>> +#define DMC620_PMU_CLK_REQUEST 0x21
>> +#define DMC620_PMU_CLK_UPLOAD_STALL 0x22
>> +#define DMC620_PMU_CLK_INDICATE_MASK 0x20
>> +
>> +struct arm_dmc620_pmu {
>> + struct pmu pmu;
>> + struct platform_device *pdev;
>> +
>> + void __iomem *pmu_csr;
>> + int irq;
>> + cpumask_t cpu;
>> + struct hlist_node hotplug_node;
>> +
>> + /*
>> + * We put all clkdiv2 and clk counters to a same array.
>> + * The first DMC620_PMU_CLKDIV2_MAX_COUNTERS bits belong to
>> + * clkdiv2 counters, the last DMC620_PMU_CLK_MAX_COUNTERS
>> + * belong to clk counters.
>> + */
>> + DECLARE_BITMAP(used_mask, DMC620_PMU_MAX_COUNTERS);
>> + struct perf_event *act_counter[DMC620_PMU_MAX_COUNTERS];
>> +};
>> +
>> +#define to_dmc620_pmu(p) (container_of(p, struct arm_dmc620_pmu, pmu))
>> +
>> +/* Keep track of our dynamic hotplug state */
>> +static enum cpuhp_state arm_dmc620_pmu_online;
>> +
>> +static ssize_t
>> +dmc620_pmu_events_sysfs_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%03llx\n", pmu_attr->id);
>> +}
>> +
>> +#define DMC620_PMU_EVENT_ATTR(name, config) \
>> + PMU_EVENT_ATTR(name, dmc620_pmu_event_attr_##name, \
>> + config, dmc620_pmu_events_sysfs_show)
>> +
>
> How about this and can simplify the event attributes?
>
> #define DMC620_PMU_EVENT_ATTR(name, config) \
> (&((struct perf_pmu_events_attr) { \
> .attr = __ATTR(name, 0444, dmc620_pmu_events_sysfs_show, NULL), \
> .id = config, \
> }).attr.attr)
>
> static struct attribute *arm_dmc620_pmu_events_attrs[] = {
> DMC620_PMU_EVENT_ATTR(clkdiv2_cycle_count, DMC620_PMU_CLKDIV2_CYCLE_COUNT),
> ......
> };
=> Thanks for the suggestion. Though, the usage of PMU_EVENT_ATTR is better because it is defined in perf_event.h and if there are any changes in the structure format later, we donât need to update the drive, right?
>
>
> Thanks,
> Shaokun
>
>> +/* clkdiv2 events list */
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_cycle_count,
>> + DMC620_PMU_CLKDIV2_CYCLE_COUNT);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_allocate,
>> + DMC620_PMU_CLKDIV2_ALLOCATE);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_queue_depth,
>> + DMC620_PMU_CLKDIV2_QUEUE_DEPTH);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_waiting_for_wr_data,
>> + DMC620_PMU_CLKDIV2_WAITING_FOR_WR_DATA);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_read_backlog,
>> + DMC620_PMU_CLKDIV2_READ_BACKLOG);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_waiting_for_mi,
>> + DMC620_PMU_CLKDIV2_WAITING_FOR_MI);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_hazard_resolution,
>> + DMC620_PMU_CLKDIV2_HAZARD_RESOLUTION);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_enqueue,
>> + DMC620_PMU_CLKDIV2_ENQUEUE);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_arbitrate,
>> + DMC620_PMU_CLKDIV2_ARBITRATE);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_lrank_turnaround_activate,
>> + DMC620_PMU_CLKDIV2_LRANK_TURNAROUND_ACTIVATE);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_prank_turnaround_activate,
>> + DMC620_PMU_CLKDIV2_PRANK_TURNAROUND_ACTIVATE);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_read_depth,
>> + DMC620_PMU_CLKDIV2_READ_DEPTH);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_write_depth,
>> + DMC620_PMU_CLKDIV2_WRITE_DEPTH);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_highigh_qos_depth,
>> + DMC620_PMU_CLKDIV2_HIGHHIGH_QOS_DEPTH);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_high_qos_depth,
>> + DMC620_PMU_CLKDIV2_HIGH_QOS_DEPTH);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_medium_qos_depth,
>> + DMC620_PMU_CLKDIV2_MEDIUM_QOS_DEPTH);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_low_qos_depth,
>> + DMC620_PMU_CLKDIV2_LOW_QOS_DEPTH);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_activate,
>> + DMC620_PMU_CLKDIV2_ACTIVATE);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_rdwr,
>> + DMC620_PMU_CLKDIV2_RDWR);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_refresh,
>> + DMC620_PMU_CLKDIV2_REFRESH);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_training_request,
>> + DMC620_PMU_CLKDIV2_TRAINING_REQUEST);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_t_mac_tracker,
>> + DMC620_PMU_CLKDIV2_T_MAC_TRACKER);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_bk_fsm_tracker,
>> + DMC620_PMU_CLKDIV2_BK_FSM_TRACKER);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_bk_open_tracker,
>> + DMC620_PMU_CLKDIV2_BK_OPEN_TRACKER);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_ranks_in_pwr_down,
>> + DMC620_PMU_CLKDIV2_RANKS_IN_PWR_DOWN);
>> +DMC620_PMU_EVENT_ATTR(clkdiv2_ranks_in_sref,
>> + DMC620_PMU_CLKDIV2_RANKS_IN_SREF);
>> +
>> +/* clk events list */
>> +DMC620_PMU_EVENT_ATTR(clk_cycle_count,
>> + DMC620_PMU_CLK_CYCLE_COUNTER);
>> +DMC620_PMU_EVENT_ATTR(clk_request,
>> + DMC620_PMU_CLK_REQUEST);
>> +DMC620_PMU_EVENT_ATTR(clk_upload_stall,
>> + DMC620_PMU_CLK_UPLOAD_STALL);
>> +
>> +static struct attribute *arm_dmc620_pmu_events_attrs[] = {
>> + &dmc620_pmu_event_attr_clkdiv2_cycle_count.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_allocate.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_queue_depth.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_waiting_for_wr_data.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_read_backlog.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_waiting_for_mi.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_hazard_resolution.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_enqueue.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_arbitrate.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_lrank_turnaround_activate.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_prank_turnaround_activate.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_read_depth.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_write_depth.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_highigh_qos_depth.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_high_qos_depth.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_medium_qos_depth.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_low_qos_depth.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_activate.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_rdwr.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_refresh.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_training_request.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_t_mac_tracker.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_bk_fsm_tracker.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_bk_open_tracker.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_ranks_in_pwr_down.attr.attr,
>> + &dmc620_pmu_event_attr_clkdiv2_ranks_in_sref.attr.attr,
>> + &dmc620_pmu_event_attr_clk_cycle_count.attr.attr,
>> + &dmc620_pmu_event_attr_clk_request.attr.attr,
>> + &dmc620_pmu_event_attr_clk_upload_stall.attr.attr,
>> + NULL,
>> +};
>> +
>> +static struct attribute_group arm_dmc620_pmu_events_attr_group = {
>> + .name = "events",
>> + .attrs = arm_dmc620_pmu_events_attrs,
>> +};
>> +
>> +/* User ABI */
>> +#define ATTR_CFG_FLD_mask_CFG config
>> +#define ATTR_CFG_FLD_mask_LO 0
>> +#define ATTR_CFG_FLD_mask_HI 44
>> +#define ATTR_CFG_FLD_match_CFG config1
>> +#define ATTR_CFG_FLD_match_LO 0
>> +#define ATTR_CFG_FLD_match_HI 44
>> +#define ATTR_CFG_FLD_invert_CFG config2
>> +#define ATTR_CFG_FLD_invert_LO 0
>> +#define ATTR_CFG_FLD_invert_HI 0
>> +#define ATTR_CFG_FLD_incr_CFG config2
>> +#define ATTR_CFG_FLD_incr_LO 1
>> +#define ATTR_CFG_FLD_incr_HI 2
>> +#define ATTR_CFG_FLD_event_CFG config2
>> +#define ATTR_CFG_FLD_event_LO 3
>> +#define ATTR_CFG_FLD_event_HI 8
>> +
>> +#define __GEN_PMU_FORMAT_ATTR(cfg, lo, hi) \
>> + (lo) == (hi) ? #cfg ":" #lo "\n" : #cfg ":" #lo "-" #hi
>> +
>> +#define _GEN_PMU_FORMAT_ATTR(cfg, lo, hi) \
>> + __GEN_PMU_FORMAT_ATTR(cfg, lo, hi)
>> +
>> +#define GEN_PMU_FORMAT_ATTR(name) \
>> + PMU_FORMAT_ATTR(name, \
>> + _GEN_PMU_FORMAT_ATTR(ATTR_CFG_FLD_##name##_CFG, \
>> + ATTR_CFG_FLD_##name##_LO, \
>> + ATTR_CFG_FLD_##name##_HI))
>> +
>> +#define _ATTR_CFG_GET_FLD(attr, cfg, lo, hi) \
>> + ((((attr)->cfg) >> lo) & GENMASK(hi - lo, 0))
>> +
>> +#define ATTR_CFG_GET_FLD(attr, name) \
>> + _ATTR_CFG_GET_FLD(attr, \
>> + ATTR_CFG_FLD_##name##_CFG, \
>> + ATTR_CFG_FLD_##name##_LO, \
>> + ATTR_CFG_FLD_##name##_HI)
>> +
>> +GEN_PMU_FORMAT_ATTR(mask);
>> +GEN_PMU_FORMAT_ATTR(match);
>> +GEN_PMU_FORMAT_ATTR(invert);
>> +GEN_PMU_FORMAT_ATTR(incr);
>> +GEN_PMU_FORMAT_ATTR(event);
>> +
>> +static struct attribute *arm_dmc620_pmu_formats_attrs[] = {
>> + &format_attr_mask.attr,
>> + &format_attr_match.attr,
>> + &format_attr_invert.attr,
>> + &format_attr_incr.attr,
>> + &format_attr_event.attr,
>> + NULL,
>> +};
>> +
>> +static struct attribute_group arm_dmc620_pmu_format_attr_group = {
>> + .name = "format",
>> + .attrs = arm_dmc620_pmu_formats_attrs,
>> +};
>> +
>> +static const struct attribute_group *arm_dmc620_pmu_attr_groups[] = {
>> + &arm_dmc620_pmu_events_attr_group,
>> + &arm_dmc620_pmu_format_attr_group,
>> + NULL,
>> +};
>> +
>> +static inline
>> +unsigned int arm_dmc620_pmu_counter_read32(struct arm_dmc620_pmu *dmc620_pmu,
>> + unsigned int idx,
>> + unsigned int offset)
>> +{
>> + return readl(dmc620_pmu->pmu_csr + DMC620_PMU_COUNTERS_BASE_OFFSET +
>> + (idx * DMC620_PMU_COUNTER_REG_BYTE_LENGTH + offset));
>> +}
>> +
>> +static inline
>> +void arm_dmc620_pmu_counter_write32(struct arm_dmc620_pmu *dmc620_pmu,
>> + unsigned int idx,
>> + unsigned int offset,
>> + unsigned int val)
>> +{
>> + writel(val, dmc620_pmu->pmu_csr + DMC620_PMU_COUNTERS_BASE_OFFSET +
>> + (idx * DMC620_PMU_COUNTER_REG_BYTE_LENGTH + offset));
>> +}
>> +
>> +static
>> +unsigned int arm_dmc620_event_to_counter_control(struct perf_event *event)
>> +{
>> + struct perf_event_attr *attr = &event->attr;
>> + unsigned int reg = 0;
>> +
>> + reg |= ATTR_CFG_GET_FLD(attr, invert) <<
>> + DMC620_PMU_COUNTER_CONTROL_INVERT_SHIFT;
>> + reg |= ATTR_CFG_GET_FLD(attr, incr) <<
>> + DMC620_PMU_COUNTER_CONTROL_INCR_SHIFT;
>> + reg |= (ATTR_CFG_GET_FLD(attr, event) &
>> + ~DMC620_PMU_CLK_INDICATE_MASK) <<
>> + DMC620_PMU_COUNTER_CONTROL_EVENT_MUX_SHIFT;
>> +
>> + return reg;
>> +}
>> +
>> +static int arm_dmc620_get_event_idx(struct perf_event *event)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu);
>> + struct perf_event_attr *attr = &event->attr;
>> + int start_idx, end_idx;
>> + int idx;
>> +
>> + if (ATTR_CFG_GET_FLD(attr, event) & DMC620_PMU_CLK_INDICATE_MASK) {
>> + /* clk events are selected */
>> + start_idx = DMC620_PMU_CLKDIV2_MAX_COUNTERS;
>> + end_idx = DMC620_PMU_MAX_COUNTERS;
>> + } else {
>> + start_idx = 0;
>> + end_idx = DMC620_PMU_CLKDIV2_MAX_COUNTERS;
>> + }
>> +
>> + for (idx = start_idx; idx < end_idx; ++idx) {
>> + if (!test_and_set_bit(idx, dmc620_pmu->used_mask))
>> + return idx;
>> + }
>> +
>> + /* The counters are all in use. */
>> + return -EAGAIN;
>> +}
>> +
>> +static u64 arm_dmc620_pmu_read_counter(struct perf_event *event)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu);
>> +
>> + return (u64)arm_dmc620_pmu_counter_read32(dmc620_pmu,
>> + event->hw.idx,
>> + DMC620_PMU_COUNTER_VALUE_OFFSET);
>> +}
>> +
>> +static void arm_dmc620_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 = arm_dmc620_pmu_read_counter(event);
>> + } while (local64_cmpxchg(&hwc->prev_count,
>> + prev_count, new_count) != prev_count);
>> + delta = (new_count - prev_count) & DMC620_CNT_MAX_PERIOD;
>> + local64_add(delta, &event->count);
>> +}
>> +
>> +static void arm_dmc620_pmu_event_set_period(struct perf_event *event)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu);
>> +
>> + /*
>> + * All DMC-620 PMU event counters are 32bit counters.
>> + * To handle cases of extreme interrupt latency, we program
>> + * the counter with half of the max count for the counters.
>> + */
>> + u64 val = DMC620_CNT_MAX_PERIOD >> 1;
>> +
>> + local64_set(&event->hw.prev_count, val);
>> + arm_dmc620_pmu_counter_write32(dmc620_pmu,
>> + event->hw.idx, DMC620_PMU_COUNTER_VALUE_OFFSET,
>> + val);
>> +}
>> +
>> +static void arm_dmc620_pmu_enable_counter(struct perf_event *event)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu);
>> + unsigned int reg;
>> +
>> + reg = arm_dmc620_pmu_counter_read32(dmc620_pmu,
>> + event->hw.idx, DMC620_PMU_COUNTER_CONTROL_OFFSET);
>> + reg |= DMC620_PMU_COUNTER_CONTROL_ENABLE_MASK;
>> + arm_dmc620_pmu_counter_write32(dmc620_pmu,
>> + event->hw.idx, DMC620_PMU_COUNTER_CONTROL_OFFSET,
>> + reg);
>> +}
>> +
>> +static void arm_dmc620_pmu_disable_counter(struct perf_event *event)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu);
>> + unsigned int reg;
>> +
>> + reg = arm_dmc620_pmu_counter_read32(dmc620_pmu,
>> + event->hw.idx, DMC620_PMU_COUNTER_CONTROL_OFFSET);
>> + reg &= ~DMC620_PMU_COUNTER_CONTROL_ENABLE_MASK;
>> + arm_dmc620_pmu_counter_write32(dmc620_pmu,
>> + event->hw.idx, DMC620_PMU_COUNTER_CONTROL_OFFSET,
>> + reg);
>> +}
>> +
>> +static irqreturn_t arm_dmc620_pmu_handle_irq(int irq_num, void *dev)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu = dev;
>> + struct perf_event *event;
>> + bool handled = false;
>> + unsigned long overflow_clkdiv2, overflow_clk;
>> + int i;
>> +
>> + overflow_clkdiv2 = readl(dmc620_pmu->pmu_csr +
>> + DMC620_PMU_OVERFLOW_STATUS_CLKDIV2_OFFSET);
>> + overflow_clk = readl(dmc620_pmu->pmu_csr +
>> + DMC620_PMU_OVERFLOW_STATUS_CLK_OFFSET);
>> + if (!overflow_clkdiv2 && !overflow_clk)
>> + return IRQ_NONE;
>> +
>> + for_each_set_bit(i, &overflow_clkdiv2,
>> + DMC620_PMU_CLKDIV2_MAX_COUNTERS) {
>> + /* clkdiv2 event overflow */
>> + event = dmc620_pmu->act_counter[i];
>> + if (!event)
>> + continue;
>> + arm_dmc620_pmu_disable_counter(event);
>> + arm_dmc620_pmu_event_update(event);
>> + arm_dmc620_pmu_event_set_period(event);
>> + arm_dmc620_pmu_enable_counter(event);
>> + handled = true;
>> + }
>> +
>> + for_each_set_bit(i, &overflow_clk,
>> + DMC620_PMU_CLK_MAX_COUNTERS) {
>> + /* clk event overflow */
>> + event = dmc620_pmu->act_counter[i +
>> + DMC620_PMU_CLKDIV2_MAX_COUNTERS];
>> + if (!event)
>> + continue;
>> + arm_dmc620_pmu_disable_counter(event);
>> + arm_dmc620_pmu_event_update(event);
>> + arm_dmc620_pmu_event_set_period(event);
>> + arm_dmc620_pmu_enable_counter(event);
>> + handled = true;
>> + }
>> +
>> + if (overflow_clkdiv2)
>> + writel(0, dmc620_pmu->pmu_csr +
>> + DMC620_PMU_OVERFLOW_STATUS_CLKDIV2_OFFSET);
>> + if (overflow_clk)
>> + writel(0, dmc620_pmu->pmu_csr +
>> + DMC620_PMU_OVERFLOW_STATUS_CLK_OFFSET);
>> +
>> + return IRQ_RETVAL(handled);
>> +}
>> +
>> +static int arm_dmc620_pmu_event_init(struct perf_event *event)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu);
>> + struct hw_perf_event *hwc = &event->hw;
>> + struct perf_event *sibling;
>> +
>> + if (event->attr.type != event->pmu->type)
>> + return -ENOENT;
>> +
>> + /*
>> + * DMC 620 PMUs are shared across all cpus and cannot
>> + * support task bound and sampling events.
>> + */
>> + if (is_sampling_event(event) ||
>> + event->attach_state & PERF_ATTACH_TASK) {
>> + dev_dbg(dmc620_pmu->pmu.dev,
>> + "Can't support per-task counters\n");
>> + return -EOPNOTSUPP;
>> + }
>> +
>> + if (event->cpu < 0) {
>> + dev_dbg(dmc620_pmu->pmu.dev,
>> + "Per-task mode not supported\n");
>> + return -EOPNOTSUPP;
>> + }
>> + /*
>> + * 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, where each
>> + * event could be theoretically assigned to a different CPU. To
>> + * mitigate this, we enforce CPU assignment to one, selected
>> + * processor.
>> + */
>> + event->cpu = cpumask_first(&dmc620_pmu->cpu);
>> +
>> + /*
>> + * We must NOT create groups containing mixed PMUs, although software
>> + * events are acceptable
>> + */
>> + if (event->group_leader->pmu != event->pmu &&
>> + !is_software_event(event->group_leader))
>> + return -EINVAL;
>> +
>> + for_each_sibling_event(sibling, event->group_leader) {
>> + if (sibling->pmu != event->pmu &&
>> + !is_software_event(sibling))
>> + return -EINVAL;
>> + }
>> +
>> + hwc->idx = -1;
>> + return 0;
>> +}
>> +
>> +static void arm_dmc620_pmu_read(struct perf_event *event)
>> +{
>> + arm_dmc620_pmu_event_update(event);
>> +}
>> +
>> +static void arm_dmc620_pmu_start(struct perf_event *event, int flags)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu);
>> +
>> + event->hw.state = 0;
>> + arm_dmc620_pmu_event_set_period(event);
>> +
>> + if (flags & PERF_EF_RELOAD) {
>> + unsigned long prev_raw_count =
>> + local64_read(&event->hw.prev_count);
>> +
>> + arm_dmc620_pmu_counter_write32(dmc620_pmu,
>> + event->hw.idx, DMC620_PMU_COUNTER_VALUE_OFFSET,
>> + (unsigned int)prev_raw_count);
>> + }
>> + arm_dmc620_pmu_enable_counter(event);
>> +}
>> +
>> +static void arm_dmc620_pmu_stop(struct perf_event *event, int flags)
>> +{
>> + if (event->hw.state & PERF_HES_STOPPED)
>> + return;
>> +
>> + arm_dmc620_pmu_disable_counter(event);
>> + arm_dmc620_pmu_event_update(event);
>> + event->hw.state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
>> +}
>> +
>> +static int arm_dmc620_pmu_add(struct perf_event *event, int flags)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu);
>> + struct hw_perf_event *hwc = &event->hw;
>> + struct perf_event_attr *attr = &event->attr;
>> + unsigned long reg;
>> + int idx = 0;
>> +
>> + idx = arm_dmc620_get_event_idx(event);
>> + if (idx < 0)
>> + return idx;
>> +
>> + hwc->idx = idx;
>> + dmc620_pmu->act_counter[idx] = event;
>> + hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
>> +
>> + /* Write to mask 31-00 register */
>> + reg = ATTR_CFG_GET_FLD(attr, mask);
>> + arm_dmc620_pmu_counter_write32(dmc620_pmu,
>> + event->hw.idx, DMC620_PMU_COUNTER_MASK_31_00_OFFSET,
>> + (unsigned int)(reg & 0xffffffff));
>> + /* Write to mask 63-32 register */
>> + arm_dmc620_pmu_counter_write32(dmc620_pmu,
>> + event->hw.idx, DMC620_PMU_COUNTER_MASK_63_32_OFFSET,
>> + (unsigned int)(reg >> 32));
>> +
>> + /* Write to match 31-00 register */
>> + reg = ATTR_CFG_GET_FLD(attr, match);
>> + arm_dmc620_pmu_counter_write32(dmc620_pmu,
>> + event->hw.idx, DMC620_PMU_COUNTER_MATCH_31_00_OFFSET,
>> + (unsigned int)(reg & 0xffffffff));
>> + /* Write to match 63-32 register */
>> + arm_dmc620_pmu_counter_write32(dmc620_pmu,
>> + event->hw.idx, DMC620_PMU_COUNTER_MATCH_63_32_OFFSET,
>> + (unsigned int)(reg >> 32));
>> +
>> + /* Write to control register */
>> + reg = arm_dmc620_event_to_counter_control(event);
>> + arm_dmc620_pmu_counter_write32(dmc620_pmu,
>> + event->hw.idx, DMC620_PMU_COUNTER_CONTROL_OFFSET,
>> + (unsigned int)reg);
>> +
>> + if (flags & PERF_EF_START)
>> + arm_dmc620_pmu_start(event, PERF_EF_RELOAD);
>> +
>> + perf_event_update_userpage(event);
>> + return 0;
>> +}
>> +
>> +static void arm_dmc620_pmu_del(struct perf_event *event, int flags)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu = to_dmc620_pmu(event->pmu);
>> + struct hw_perf_event *hwc = &event->hw;
>> + int idx = hwc->idx;
>> +
>> + arm_dmc620_pmu_stop(event, PERF_EF_UPDATE);
>> + dmc620_pmu->act_counter[idx] = NULL;
>> + clear_bit(idx, dmc620_pmu->used_mask);
>> + perf_event_update_userpage(event);
>> +}
>> +
>> +static int arm_dmc620_pmu_perf_init(struct arm_dmc620_pmu *dmc620_pmu)
>> +{
>> + struct device *dev = &dmc620_pmu->pdev->dev;
>> + unsigned long long value;
>> + char *name;
>> + acpi_handle handle;
>> + acpi_status status;
>> +
>> + dmc620_pmu->pmu = (struct pmu) {
>> + .capabilities = PERF_PMU_CAP_NO_EXCLUDE,
>> + .task_ctx_nr = perf_invalid_context,
>> + .event_init = arm_dmc620_pmu_event_init,
>> + .add = arm_dmc620_pmu_add,
>> + .del = arm_dmc620_pmu_del,
>> + .start = arm_dmc620_pmu_start,
>> + .stop = arm_dmc620_pmu_stop,
>> + .read = arm_dmc620_pmu_read,
>> + .attr_groups = arm_dmc620_pmu_attr_groups,
>> + };
>> +
>> + handle = ACPI_HANDLE(dev);
>> + if (!handle)
>> + return -ENODEV;
>> +
>> + status = acpi_evaluate_integer(handle, METHOD_NAME__UID, NULL,
>> + &value);
>> + if (ACPI_FAILURE(status)) {
>> + dev_err(dev, "Failed to evaluate _UID (0x%x)\n", status);
>> + return -ENODEV;
>> + }
>> +
>> + name = devm_kasprintf(dev, GFP_KERNEL, "%s_%d", PMUNAME,
>> + (unsigned int)value);
>> +
>> + return perf_pmu_register(&dmc620_pmu->pmu, name, -1);
>> +}
>> +
>> +static void arm_dmc620_pmu_perf_destroy(struct arm_dmc620_pmu *dmc620_pmu)
>> +{
>> + perf_pmu_unregister(&dmc620_pmu->pmu);
>> +}
>> +
>> +static int arm_dmc620_pmu_cpu_startup(unsigned int cpu,
>> + struct hlist_node *node)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu = hlist_entry_safe(node,
>> + struct arm_dmc620_pmu,
>> + hotplug_node);
>> +
>> + dmc620_pmu = hlist_entry_safe(node, struct arm_dmc620_pmu,
>> + hotplug_node);
>> + if (cpumask_empty(&dmc620_pmu->cpu))
>> + cpumask_set_cpu(cpu, &dmc620_pmu->cpu);
>> +
>> + /* Overflow interrupt also should use the same CPU */
>> + WARN_ON(irq_set_affinity(dmc620_pmu->irq, &dmc620_pmu->cpu));
>> +
>> + return 0;
>> +}
>> +
>> +static int arm_dmc620_pmu_cpu_teardown(unsigned int cpu,
>> + struct hlist_node *node)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu = hlist_entry_safe(node,
>> + struct arm_dmc620_pmu,
>> + hotplug_node);
>> + unsigned int target;
>> +
>> + if (!cpumask_test_and_clear_cpu(cpu, &dmc620_pmu->cpu))
>> + return 0;
>> +
>> + target = cpumask_any_but(cpu_online_mask, cpu);
>> + if (target >= nr_cpu_ids)
>> + return 0;
>> +
>> + cpumask_set_cpu(target, &dmc620_pmu->cpu);
>> +
>> + /* Overflow interrupt also should use the same CPU */
>> + WARN_ON(irq_set_affinity(dmc620_pmu->irq, &dmc620_pmu->cpu));
>> +
>> + return 0;
>> +}
>> +
>> +static int arm_dmc620_pmu_dev_init(struct arm_dmc620_pmu *dmc620_pmu)
>> +{
>> + struct platform_device *pdev = dmc620_pmu->pdev;
>> + int ret;
>> +
>> + ret = devm_request_irq(&pdev->dev, dmc620_pmu->irq,
>> + arm_dmc620_pmu_handle_irq,
>> + IRQF_SHARED,
>> + dev_name(&pdev->dev), dmc620_pmu);
>> + if (ret)
>> + dev_err(&pdev->dev,
>> + "Could not request IRQ %d\n", dmc620_pmu->irq);
>> +
>> + /*
>> + * Register our hotplug notifier now so we don't miss any events.
>> + */
>> + return cpuhp_state_add_instance(arm_dmc620_pmu_online,
>> + &dmc620_pmu->hotplug_node);
>> +}
>> +
>> +static void arm_dmc620_pmu_dev_teardown(struct arm_dmc620_pmu *dmc620_pmu)
>> +{
>> + cpuhp_state_remove_instance(arm_dmc620_pmu_online,
>> + &dmc620_pmu->hotplug_node);
>> +}
>> +
>> +static int arm_dmc620_pmu_resource_probe(struct arm_dmc620_pmu *dmc620_pmu)
>> +{
>> + struct platform_device *pdev = dmc620_pmu->pdev;
>> + struct resource *res;
>> + int irq;
>> +
>> + irq = platform_get_irq(pdev, 0);
>> + if (irq < 0) {
>> + dev_err(&pdev->dev, "failed to get IRQ (%d)\n", irq);
>> + return -ENXIO;
>> + }
>> + dmc620_pmu->irq = irq;
>> +
>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> + dmc620_pmu->pmu_csr = devm_ioremap_resource(&pdev->dev, res);
>> + if (IS_ERR(dmc620_pmu->pmu_csr)) {
>> + dev_err(&pdev->dev,
>> + "ioremap failed for DMC-620 PMU resource\n");
>> + return -ENXIO;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int arm_dmc620_pmu_device_probe(struct platform_device *pdev)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu;
>> + struct device *dev = &pdev->dev;
>> + int ret;
>> +
>> + dmc620_pmu = devm_kzalloc(dev, sizeof(*dmc620_pmu), GFP_KERNEL);
>> + if (!dmc620_pmu)
>> + return -ENOMEM;
>> +
>> + dmc620_pmu->pdev = pdev;
>> + platform_set_drvdata(pdev, dmc620_pmu);
>> +
>> + ret = arm_dmc620_pmu_resource_probe(dmc620_pmu);
>> + if (ret)
>> + return ret;
>> +
>> + ret = arm_dmc620_pmu_dev_init(dmc620_pmu);
>> + if (ret)
>> + return ret;
>> +
>> + ret = arm_dmc620_pmu_perf_init(dmc620_pmu);
>> + if (ret)
>> + goto out_teardown_dev;
>> +
>> + return 0;
>> +
>> +out_teardown_dev:
>> + arm_dmc620_pmu_dev_teardown(dmc620_pmu);
>> + return ret;
>> +}
>> +
>> +static int arm_dmc620_pmu_device_remove(struct platform_device *pdev)
>> +{
>> + struct arm_dmc620_pmu *dmc620_pmu = platform_get_drvdata(pdev);
>> +
>> + arm_dmc620_pmu_perf_destroy(dmc620_pmu);
>> + arm_dmc620_pmu_dev_teardown(dmc620_pmu);
>> + return 0;
>> +}
>> +
>> +static const struct acpi_device_id arm_dmc620_acpi_match[] = {
>> + { "ARMHD620", 0},
>> + {},
>> +};
>> +MODULE_DEVICE_TABLE(acpi, arm_dmc620_acpi_match);
>> +static struct platform_driver arm_dmc620_pmu_driver = {
>> + .driver = {
>> + .name = DRVNAME,
>> + .acpi_match_table = ACPI_PTR(arm_dmc620_acpi_match),
>> + },
>> + .probe = arm_dmc620_pmu_device_probe,
>> + .remove = arm_dmc620_pmu_device_remove,
>> +};
>> +
>> +static int __init arm_dmc620_pmu_init(void)
>> +{
>> + int ret;
>> +
>> + ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, DRVNAME,
>> + arm_dmc620_pmu_cpu_startup,
>> + arm_dmc620_pmu_cpu_teardown);
>> + if (ret < 0)
>> + return ret;
>> +
>> + arm_dmc620_pmu_online = ret;
>> +
>> + ret = platform_driver_register(&arm_dmc620_pmu_driver);
>> + if (ret)
>> + cpuhp_remove_multi_state(arm_dmc620_pmu_online);
>> +
>> + return ret;
>> +}
>> +
>> +static void __exit arm_dmc620_pmu_exit(void)
>> +{
>> + platform_driver_unregister(&arm_dmc620_pmu_driver);
>> + cpuhp_remove_multi_state(arm_dmc620_pmu_online);
>> +}
>> +
>> +module_init(arm_dmc620_pmu_init);
>> +module_exit(arm_dmc620_pmu_exit);
>> +
>> +MODULE_DESCRIPTION("Perf driver for the ARM DMC-620 memory controller");
>> +MODULE_AUTHOR("Tuan Phan <tuanphan@xxxxxxxxxxxxxxxxxxxxxx");
>> +MODULE_LICENSE("GPL v2");
>>
>