Please see inline
> -----Original Message-----
> From: John Garry <john.garry@xxxxxxxxxx>
> Sent: Wednesday, August 18, 2021 7:19 PM
> To: Bharat Bhushan <bbhushan2@xxxxxxxxxxx>; will@xxxxxxxxxx;
> mark.rutland@xxxxxxx; robh+dt@xxxxxxxxxx; linux-arm-
> kernel@xxxxxxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx
> Subject: [EXT] Re: [PATCH v2 2/4] perf/marvell: CN10k DDR performance monitor
> support
>
> External Email
>
> ----------------------------------------------------------------------
> On 10/08/2021 10:43, Bharat Bhushan wrote:
> > Marvell CN10k DRAM Subsystem (DSS) supports eight
> > event counters for monitoring performance and software
> > can program each counter to monitor any of the defined
> > performance event. Performance events are for interface
> > between the DDR controller and the PHY, interface between
> > the DDR Controller and the CHI interconnect, or within
> > the DDR Controller. Additionally DSS also supports two
> > fixed performance event counters, one for number of
> > ddr reads and other for ddr writes.
> >
> > This patch add basic support for these performance
> > monitoring events on CN10k.
>
> please use full 75 char width
Ok,
>
> >
> > Signed-off-by: Bharat Bhushan <bbhushan2@xxxxxxxxxxx>
> > ---
> > v1->v2:
> > - writeq/readq changed to respective relaxed version
> > - Using PMU_EVENT_ATTR_ID
> >
> > drivers/perf/Kconfig | 7 +
> > drivers/perf/Makefile | 1 +
> > drivers/perf/marvell_cn10k_ddr_pmu.c | 606 +++++++++++++++++++++++++++
> > 3 files changed, 614 insertions(+)
> > create mode 100644 drivers/perf/marvell_cn10k_ddr_pmu.c
> >
> > diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig
> > index 77522e5efe11..41a80a4b8d29 100644
> > --- a/drivers/perf/Kconfig
> > +++ b/drivers/perf/Kconfig
> > @@ -139,4 +139,11 @@ config ARM_DMC620_PMU
> >
> > source "drivers/perf/hisilicon/Kconfig"
> >
> > +config MARVELL_CN10K_DDR_PMU
> > + tristate "Enable MARVELL CN10K DRAM Subsystem(DSS) PMU Support"
> > + depends on ARM64
>
> Is there anything to stop using adding COMPILE_TEST as a dependency?
> This really helps build coverage testing for other archs
Just keeping same as other drivers
>
> > + help
> > + Enable perf support for Marvell DDR Performance monitoring
> > + event on CN10K platform.
> > +
> > endmenu
> > diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile
> > index 5260b116c7da..ee1126219d8d 100644
> > --- a/drivers/perf/Makefile
> > +++ b/drivers/perf/Makefile
> > @@ -14,3 +14,4 @@ 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_DMC620_PMU) += arm_dmc620_pmu.o
> > +obj-$(CONFIG_MARVELL_CN10K_DDR_PMU) += marvell_cn10k_ddr_pmu.o
> > diff --git a/drivers/perf/marvell_cn10k_ddr_pmu.c
> b/drivers/perf/marvell_cn10k_ddr_pmu.c
> > new file mode 100644
> > index 000000000000..8f9e3d1fcd8d
> > --- /dev/null
> > +++ b/drivers/perf/marvell_cn10k_ddr_pmu.c
> > @@ -0,0 +1,606 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/* Marvell CN10K DRAM Subsystem (DSS) Performance Monitor Driver
> > + *
> > + * Copyright (C) 2021 Marvell.
> > + */
> > +
> > +#include <linux/init.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>
> > +
> > +/* Performance Counters Operating Mode Control Registers */
> > +#define DDRC_PERF_CNT_OP_MODE_CTRL 0x8020
> > +#define OP_MODE_CTRL_VAL_MANNUAL 0x1
> > +
> > +/* Performance Counters Start Operation Control Registers */
> > +#define DDRC_PERF_CNT_START_OP_CTRL 0x8028
> > +#define START_OP_CTRL_VAL_START 0x1ULL
> > +#define START_OP_CTRL_VAL_ACTIVE 0x2
> > +
> > +/* Performance Counters End Operation Control Registers */
> > +#define DDRC_PERF_CNT_END_OP_CTRL 0x8030
> > +#define END_OP_CTRL_VAL_END 0x1ULL
> > +
> > +/* Performance Counters End Status Registers */
> > +#define DDRC_PERF_CNT_END_STATUS 0x8038
> > +#define END_STATUS_VAL_END_TIMER_MODE_END 0x1
> > +
> > +/* Performance Counters Configuration Registers */
> > +#define DDRC_PERF_CFG_BASE 0x8040
> > +
> > +/* 8 Generic event counter + 2 fixed event counters */
> > +#define DDRC_PERF_NUM_GEN_COUNTERS 8
> > +#define DDRC_PERF_NUM_FIX_COUNTERS 2
> > +#define DDRC_PERF_READ_COUNTER_IDX
> DDRC_PERF_NUM_GEN_COUNTERS
> > +#define DDRC_PERF_WRITE_COUNTER_IDX
> (DDRC_PERF_NUM_GEN_COUNTERS + 1)
> > +#define DDRC_PERF_NUM_COUNTERS
> (DDRC_PERF_NUM_GEN_COUNTERS + \
> > + DDRC_PERF_NUM_FIX_COUNTERS)
> > +
> > +/* Generic event counter registers */
> > +#define DDRC_PERF_CFG(n) (DDRC_PERF_CFG_BASE + 8 * (n))
> > +#define EVENT_ENABLE BIT_ULL(63)
> > +
> > +/* Two dedicated event counters for DDR reads and writes */
> > +#define EVENT_DDR_READS 101
> > +#define EVENT_DDR_WRITES 100
> > +
> > +/*
> > + * programmable events IDs in programmable event counters.
> > + * DO NOT change these event-id numbers, they are used to
> > + * program event bitmap in h/w.
> > + */
> > +#define EVENT_OP_IS_ZQLATCH 55
> > +#define EVENT_OP_IS_ZQSTART 54
> > +#define EVENT_OP_IS_TCR_MRR 53
> > +#define EVENT_OP_IS_DQSOSC_MRR 52
> > +#define EVENT_OP_IS_DQSOSC_MPC 51
> > +#define EVENT_VISIBLE_WIN_LIMIT_REACHED_WR 50
> > +#define EVENT_VISIBLE_WIN_LIMIT_REACHED_RD 49
> > +#define EVENT_BSM_STARVATION 48
> > +#define EVENT_BSM_ALLOC 47
> > +#define EVENT_LPR_REQ_WITH_NOCREDIT 46
> > +#define EVENT_HPR_REQ_WITH_NOCREDIT 45
> > +#define EVENT_OP_IS_ZQCS 44
> > +#define EVENT_OP_IS_ZQCL 43
> > +#define EVENT_OP_IS_LOAD_MODE 42
> > +#define EVENT_OP_IS_SPEC_REF 41
> > +#define EVENT_OP_IS_CRIT_REF 40
> > +#define EVENT_OP_IS_REFRESH 39
> > +#define EVENT_OP_IS_ENTER_MPSM 35
> > +#define EVENT_OP_IS_ENTER_POWERDOWN 31
> > +#define EVENT_OP_IS_ENTER_SELFREF 27
> > +#define EVENT_WAW_HAZARD 26
> > +#define EVENT_RAW_HAZARD 25
> > +#define EVENT_WAR_HAZARD 24
> > +#define EVENT_WRITE_COMBINE 23
> > +#define EVENT_RDWR_TRANSITIONS 22
> > +#define EVENT_PRECHARGE_FOR_OTHER 21
> > +#define EVENT_PRECHARGE_FOR_RDWR 20
> > +#define EVENT_OP_IS_PRECHARGE 19
> > +#define EVENT_OP_IS_MWR 18
> > +#define EVENT_OP_IS_WR 17
> > +#define EVENT_OP_IS_RD 16
> > +#define EVENT_OP_IS_RD_ACTIVATE 15
> > +#define EVENT_OP_IS_RD_OR_WR 14
> > +#define EVENT_OP_IS_ACTIVATE 13
> > +#define EVENT_WR_XACT_WHEN_CRITICAL 12
> > +#define EVENT_LPR_XACT_WHEN_CRITICAL 11
> > +#define EVENT_HPR_XACT_WHEN_CRITICAL 10
> > +#define EVENT_DFI_RD_DATA_CYCLES 9
> > +#define EVENT_DFI_WR_DATA_CYCLES 8
> > +#define EVENT_ACT_BYPASS 7
> > +#define EVENT_READ_BYPASS 6
> > +#define EVENT_HIF_HI_PRI_RD 5
> > +#define EVENT_HIF_RMW 4
> > +#define EVENT_HIF_RD 3
> > +#define EVENT_HIF_WR 2
> > +#define EVENT_HIF_RD_OR_WR 1
> > +
> > +/* Event counter value registers */
> > +#define DDRC_PERF_CNT_VALUE_BASE 0x8080
> > +#define DDRC_PERF_CNT_VALUE(n) (DDRC_PERF_CNT_VALUE_BASE + 8 * (n))
> > +
> > +/* Fixed event counter enable/disable register */
> > +#define DDRC_PERF_CNT_FREERUN_EN 0x80C0
> > +#define DDRC_PERF_FREERUN_WRITE_EN 0x1
> > +#define DDRC_PERF_FREERUN_READ_EN 0x2
> > +
> > +/* Fixed event counter control register */
> > +#define DDRC_PERF_CNT_FREERUN_CTRL 0x80C8
> > +#define DDRC_FREERUN_WRITE_CNT_CLR 0x1
> > +#define DDRC_FREERUN_READ_CNT_CLR 0x2
> > +
> > +/* Fixed event counter value register */
> > +#define DDRC_PERF_CNT_VALUE_WR_OP 0x80D0
> > +#define DDRC_PERF_CNT_VALUE_RD_OP 0x80D8
> > +#define DDRC_PERF_CNT_VALUE_OVERFLOW BIT_ULL(48)
> > +#define DDRC_PERF_CNT_MAX_VALUE GENMASK_ULL(48, 0)
>
> I assume all these macros are used...
Yes, do you see any unused?
>
> > +
> > +struct cn10k_ddr_pmu {
> > + struct pmu pmu;
> > + int id;
> > + void __iomem *base;
> > + unsigned int cpu;
> > + struct device *dev;
> > + int active_events;
> > + struct perf_event *events[DDRC_PERF_NUM_COUNTERS];
> > +};
> > +
> > +#define to_cn10k_ddr_pmu(p) container_of(p, struct cn10k_ddr_pmu,
> pmu)
> > +
> > +static ssize_t cn10k_ddr_pmu_event_show(struct device *dev,
> > + struct device_attribute *attr,
> > + char *page)
> > +{
> > + struct perf_pmu_events_attr *pmu_attr;
> > +
> > + pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
> > + return sprintf(page, "event=0x%02llx\n", pmu_attr->id);
>
> isn't sysfs_emit() preferred now? Need to check.
Yes, Thanks for pointing.
>
> > +}
> > +
> > +#define CN10K_DDR_PMU_EVENT_ATTR(_name, _id)
> \
> > + PMU_EVENT_ATTR_ID(_name, cn10k_ddr_pmu_event_show, _id)
> > +
> > +static struct attribute *cn10k_ddr_perf_events_attrs[] = {
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_hif_rd_or_wr_access,
> EVENT_HIF_RD_OR_WR),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_hif_wr_access, EVENT_HIF_WR),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_hif_rd_access, EVENT_HIF_RD),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_hif_rmw_access,
> EVENT_HIF_RMW),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_hif_pri_rdaccess,
> EVENT_HIF_HI_PRI_RD),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_rd_bypass_access,
> EVENT_READ_BYPASS),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_act_bypass_access,
> EVENT_ACT_BYPASS),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_dif_wr_data_access,
> EVENT_DFI_WR_DATA_CYCLES),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_dif_rd_data_access,
> EVENT_DFI_RD_DATA_CYCLES),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_hpri_sched_rd_crit_access,
> > + EVENT_HPR_XACT_WHEN_CRITICAL),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_lpri_sched_rd_crit_access,
> > + EVENT_LPR_XACT_WHEN_CRITICAL),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_wr_trxn_crit_access,
> > + EVENT_WR_XACT_WHEN_CRITICAL),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_cam_active_access,
> EVENT_OP_IS_ACTIVATE),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_cam_rd_or_wr_access,
> EVENT_OP_IS_RD_OR_WR),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_cam_rd_active_access,
> EVENT_OP_IS_RD_ACTIVATE),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_cam_read, EVENT_OP_IS_RD),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_cam_write, EVENT_OP_IS_WR),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_cam_mwr, EVENT_OP_IS_MWR),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_precharge,
> EVENT_OP_IS_PRECHARGE),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_precharge_for_rdwr,
> EVENT_PRECHARGE_FOR_RDWR),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_precharge_for_other,
> > + EVENT_PRECHARGE_FOR_OTHER),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_rdwr_transitions,
> EVENT_RDWR_TRANSITIONS),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_write_combine,
> EVENT_WRITE_COMBINE),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_war_hazard,
> EVENT_WAR_HAZARD),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_raw_hazard,
> EVENT_RAW_HAZARD),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_waw_hazard,
> EVENT_WAW_HAZARD),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_enter_selfref,
> EVENT_OP_IS_ENTER_SELFREF),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_enter_powerdown,
> EVENT_OP_IS_ENTER_POWERDOWN),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_enter_mpsm,
> EVENT_OP_IS_ENTER_MPSM),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_refresh, EVENT_OP_IS_REFRESH),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_crit_ref, EVENT_OP_IS_CRIT_REF),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_spec_ref, EVENT_OP_IS_SPEC_REF),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_load_mode,
> EVENT_OP_IS_LOAD_MODE),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_zqcl, EVENT_OP_IS_ZQCL),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_cam_wr_access,
> EVENT_OP_IS_ZQCS),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_hpr_req_with_nocredit,
> > + EVENT_HPR_REQ_WITH_NOCREDIT),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_lpr_req_with_nocredit,
> > + EVENT_LPR_REQ_WITH_NOCREDIT),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_bsm_alloc, EVENT_BSM_ALLOC),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_bsm_starvation,
> EVENT_BSM_STARVATION),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_win_limit_reached_rd,
> > +
> EVENT_VISIBLE_WIN_LIMIT_REACHED_RD),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_win_limit_reached_wr,
> > +
> EVENT_VISIBLE_WIN_LIMIT_REACHED_WR),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_dqsosc_mpc,
> EVENT_OP_IS_DQSOSC_MPC),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_dqsosc_mrr,
> EVENT_OP_IS_DQSOSC_MRR),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_tcr_mrr, EVENT_OP_IS_TCR_MRR),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_zqstart, EVENT_OP_IS_ZQSTART),
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_zqlatch, EVENT_OP_IS_ZQLATCH),
> > + /* Free run event counters */
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_ddr_reads, EVENT_DDR_READS),
>
> if you want perf tool to support aliases / metrics for these then a hw
> identifer sysfs file is required, like the freescale imx8 ddr pmu driver
> has, as I assume that this PMU is not tightly coupled always to a
> specific CPU
As of now we do not have ddr pmu versioning.
>
> > + CN10K_DDR_PMU_EVENT_ATTR(ddr_ddr_writes, EVENT_DDR_WRITES),
> > + NULL,
>
> no need for ',' when the array is not going to be expanded
Oh yes,
>
> > +};
> > +
> > +static struct attribute_group cn10k_ddr_perf_events_attr_group = {
> > + .name = "events",
> > + .attrs = cn10k_ddr_perf_events_attrs,
> > +};
> > +
> > +PMU_FORMAT_ATTR(event, "config:0-8");
> > +
> > +static struct attribute *cn10k_ddr_perf_format_attrs[] = {
> > + &format_attr_event.attr,
> > + NULL,
> > +};
> > +
> > +static struct attribute_group cn10k_ddr_perf_format_attr_group = {
> > + .name = "format",
> > + .attrs = cn10k_ddr_perf_format_attrs,
> > +};
> > +
> > +static ssize_t cn10k_ddr_perf_cpumask_show(struct device *dev,
> > + struct device_attribute *attr,
> > + char *buf)
> > +{
> > + struct cn10k_ddr_pmu *pmu = dev_get_drvdata(dev);
> > +
> > + return cpumap_print_to_pagebuf(true, buf, cpumask_of(pmu->cpu));
> > +}
> > +
> > +static struct device_attribute cn10k_ddr_perf_cpumask_attr =
> > + __ATTR(cpumask, 0444, cn10k_ddr_perf_cpumask_show, NULL);
> > +
> > +static struct attribute *cn10k_ddr_perf_cpumask_attrs[] = {
> > + &cn10k_ddr_perf_cpumask_attr.attr,
> > + NULL,
> > +};
> > +
> > +static struct attribute_group cn10k_ddr_perf_cpumask_attr_group = {
> > + .attrs = cn10k_ddr_perf_cpumask_attrs,
> > +};
> > +
> > +static const struct attribute_group *cn10k_attr_groups[] = {
> > + &cn10k_ddr_perf_events_attr_group,
> > + &cn10k_ddr_perf_format_attr_group,
> > + &cn10k_ddr_perf_cpumask_attr_group,
> > + NULL,
> > +};
> > +
> > +static uint64_t ddr_perf_get_event_bitmap(int eventid)
>
> Don't we use u64 in kernel land as preference?
I am not aware of any guidance or rule, both are being used.
I end up using uint64_t and u64 both, will use one only with next version.
>
> > +{
> > + uint64_t event_bitmap = 0;
> > +
> > + switch (eventid) {
> > + case EVENT_HIF_RD_OR_WR ... EVENT_WAW_HAZARD:
> > + case EVENT_OP_IS_REFRESH ... EVENT_OP_IS_ZQLATCH:
> > + event_bitmap = (1ULL << (eventid - 1));
> > + break;
> > +
> > + case EVENT_OP_IS_ENTER_SELFREF:
> > + case EVENT_OP_IS_ENTER_POWERDOWN:
> > + case EVENT_OP_IS_ENTER_MPSM:
> > + event_bitmap = (0xFULL << (eventid - 1));
> > + break;
> > + default:
> > + pr_err("%s Invalid eventid %d\n", __func__, eventid);
>
> shouldn't this generate a proper error to its only caller (which can
> actually error)?
Ack, currently it just through error but does not error out.
>
> > + break;
> > + }
> > +
> > + return event_bitmap;
> > +}
> > +
> > +static int cn10k_ddr_perf_alloc_counter(struct cn10k_ddr_pmu *pmu,
> > + struct perf_event *event)
> > +{
> > + uint8_t config = event->attr.config;
> > + int i;
> > +
> > + /* DDR read free-run counter index */
> > + if (config == EVENT_DDR_READS) {
> > + pmu->events[DDRC_PERF_READ_COUNTER_IDX] = event;
> > + return DDRC_PERF_READ_COUNTER_IDX;
> > + }
> > +
> > + /* DDR write free-run counter index */
> > + if (config == EVENT_DDR_WRITES) {
> > + pmu->events[DDRC_PERF_WRITE_COUNTER_IDX] = event;
> > + return DDRC_PERF_WRITE_COUNTER_IDX;
> > + }
> > +
> > + /* Allocate DDR generic counters */
> > + for (i = 0; i < DDRC_PERF_NUM_GEN_COUNTERS; i++) {
> > + if (pmu->events[i] == NULL) {
> > + pmu->events[i] = event;
> > + return i;
> > + }
> > + }
> > +
> > + return -ENOENT;
> > +}
> > +
> > +static void cn10k_ddr_perf_free_counter(struct cn10k_ddr_pmu *pmu, int
> counter)
> > +{
> > + pmu->events[counter] = NULL;
> > +}
> > +
> > +static int cn10k_ddr_perf_event_init(struct perf_event *event)
> > +{
> > + struct cn10k_ddr_pmu *pmu = to_cn10k_ddr_pmu(event->pmu);
> > + struct hw_perf_event *hwc = &event->hw;
> > +
> > + if (event->attr.type != event->pmu->type)
> > + return -ENOENT;
> > +
> > + if (is_sampling_event(event)) {
> > + dev_info(pmu->dev, "Sampling not supported!\n");
> > + return -EOPNOTSUPP;
> > + }
> > +
> > + if (event->cpu < 0) {
> > + dev_warn(pmu->dev, "Can't provide per-task data!\n");
> > + return -EOPNOTSUPP;
> > + }
> > +
> > + /* We must NOT create groups containing mixed PMUs */
> > + if (event->group_leader->pmu != event->pmu &&
> > + !is_software_event(event->group_leader))
>
> pay attention to indentation
Accepted, not sure how this got in.
>
> > + return -EINVAL;
> > +
> > + /* Set ownership of event to one CPU, same event can not be observed
> > + * on multiple cpus at same time.
> > + */
> > + event->cpu = pmu->cpu;
> > + hwc->idx = -1;
> > + return 0;
> > +}
> > +
> > +static void cn10k_ddr_perf_counter_enable(struct cn10k_ddr_pmu *pmu,
> > + int counter, bool enable)
> > +{
> > + uint32_t reg;
> > + uint64_t val;
> > +
> > + if (counter > DDRC_PERF_NUM_COUNTERS) {
>
> is this paranoia?
We can not program if counter by any means is out or range.
>
> > + pr_err("Error: unsupported counter %d\n", counter);
> > + return;
> > + }
> > +
> > + if (counter < DDRC_PERF_NUM_GEN_COUNTERS) {
> > + reg = DDRC_PERF_CFG(counter);
> > + val = readq_relaxed(pmu->base + reg);
> > +
> > + if (enable)
> > + val |= EVENT_ENABLE;
> > + else
> > + val &= ~EVENT_ENABLE;
> > +
> > + writeq_relaxed(val, pmu->base + reg);
> > + } else {
> > + val = readq_relaxed(pmu->base +
> DDRC_PERF_CNT_FREERUN_EN);
> > + if (enable) {
> > + if (counter == DDRC_PERF_READ_COUNTER_IDX)
> > + val |= DDRC_PERF_FREERUN_READ_EN;
> > + else
> > + val |= DDRC_PERF_FREERUN_WRITE_EN;
> > + } else {
> > + if (counter == DDRC_PERF_READ_COUNTER_IDX)
> > + val &= ~DDRC_PERF_FREERUN_READ_EN;
> > + else
> > + val &= ~DDRC_PERF_FREERUN_WRITE_EN;
> > + }
> > + writeq_relaxed(val, pmu->base +
> DDRC_PERF_CNT_FREERUN_EN);
> > + }
> > +}
> > +
> > +static uint64_t cn10k_ddr_perf_read_counter(struct cn10k_ddr_pmu *pmu,
> > + int counter)
> > +{
> > + uint64_t val;
> > +
> > + if (counter == DDRC_PERF_READ_COUNTER_IDX)
> > + return readq_relaxed(pmu->base +
> DDRC_PERF_CNT_VALUE_RD_OP);
> > +
> > + if (counter == DDRC_PERF_WRITE_COUNTER_IDX)
> > + return readq_relaxed(pmu->base +
> DDRC_PERF_CNT_VALUE_WR_OP);
> > +
> > + val = readq_relaxed(pmu->base + DDRC_PERF_CNT_VALUE(counter));
> > + return val;
> > +}
> > +
> > +static void cn10k_ddr_perf_event_update(struct perf_event *event)
> > +{
> > + struct cn10k_ddr_pmu *pmu = to_cn10k_ddr_pmu(event->pmu);
> > + struct hw_perf_event *hwc = &event->hw;
> > + uint64_t prev_count, new_count, mask;
> > +
> > + do {
> > + prev_count = local64_read(&hwc->prev_count);
> > + new_count = cn10k_ddr_perf_read_counter(pmu, hwc->idx);
> > + } while (local64_xchg(&hwc->prev_count, new_count) != prev_count);
> > +
> > + mask = DDRC_PERF_CNT_MAX_VALUE;
> > +
> > + local64_add((new_count - prev_count) & mask, &event->count);
> > +}
> > +
> > +static void cn10k_ddr_perf_event_start(struct perf_event *event, int flags)
> > +{
> > + struct cn10k_ddr_pmu *pmu = to_cn10k_ddr_pmu(event->pmu);
> > + struct hw_perf_event *hwc = &event->hw;
> > + int counter = hwc->idx;
> > +
> > + local64_set(&hwc->prev_count, 0);
> > +
> > + cn10k_ddr_perf_counter_enable(pmu, counter, true);
> > +
> > + hwc->state = 0;
> > +}
> > +
> > +static int cn10k_ddr_perf_event_add(struct perf_event *event, int flags)
> > +{
> > + struct cn10k_ddr_pmu *pmu = to_cn10k_ddr_pmu(event->pmu);
> > + struct hw_perf_event *hwc = &event->hw;
> > + uint8_t config = event->attr.config;
> > + uint32_t reg_offset;
> > + uint64_t val;
> > + int counter;
> > +
> > + counter = cn10k_ddr_perf_alloc_counter(pmu, event);
> > + if (counter < 0) {
> > + dev_dbg(pmu->dev, "There are not enough counters\n");
>
> hmmm .. I'd be inclined to say that there are not enough available. And
> is dev_dbg() really any use?
Maybe we can remove the error print now, and return
>
> > + return -EOPNOTSUPP;
>
> is that the best error code?
Looks like we should let it try again later "-EAGAIN"
>
> > + }
> > +
> > + pmu->active_events++;
> > + hwc->idx = counter;
> > +
> > + if (counter < DDRC_PERF_NUM_GEN_COUNTERS) {
> > + /* Generic counters, configure event id */
> > + reg_offset = DDRC_PERF_CFG(counter);
> > + val = ddr_perf_get_event_bitmap(config);
> > + writeq_relaxed(val, pmu->base + reg_offset);
> > + } else {
> > + /* fixed event counter, clear counter value */
> > + if (counter == DDRC_PERF_READ_COUNTER_IDX)
> > + val = DDRC_FREERUN_READ_CNT_CLR;
> > + else
> > + val = DDRC_FREERUN_WRITE_CNT_CLR;
> > +
> > + writeq_relaxed(val, pmu->base +
> DDRC_PERF_CNT_FREERUN_CTRL);
> > + }
> > +
> > + hwc->state |= PERF_HES_STOPPED;
> > +
> > + if (flags & PERF_EF_START)
> > + cn10k_ddr_perf_event_start(event, flags);
> > +
> > + return 0;
> > +}
> > +
> > +static void cn10k_ddr_perf_event_stop(struct perf_event *event, int flags)
> > +{
> > + struct cn10k_ddr_pmu *pmu = to_cn10k_ddr_pmu(event->pmu);
> > + struct hw_perf_event *hwc = &event->hw;
> > + int counter = hwc->idx;
> > +
> > + cn10k_ddr_perf_counter_enable(pmu, counter, false);
> > +
> > + if (flags & PERF_EF_UPDATE)
> > + cn10k_ddr_perf_event_update(event);
> > +
> > + hwc->state |= PERF_HES_STOPPED;
> > +}
> > +
> > +static void cn10k_ddr_perf_event_del(struct perf_event *event, int flags)
> > +{
> > + struct cn10k_ddr_pmu *pmu = to_cn10k_ddr_pmu(event->pmu);
> > + struct hw_perf_event *hwc = &event->hw;
> > + int counter = hwc->idx;
> > +
> > + cn10k_ddr_perf_event_stop(event, PERF_EF_UPDATE);
> > +
> > + cn10k_ddr_perf_free_counter(pmu, counter);
> > + pmu->active_events--;
> > + hwc->idx = -1;
> > +}
> > +
> > +static void cn10k_ddr_perf_pmu_enable(struct pmu *pmu)
> > +{
> > + struct cn10k_ddr_pmu *ddr_pmu = to_cn10k_ddr_pmu(pmu);
> > +
> > + writeq_relaxed(START_OP_CTRL_VAL_START, ddr_pmu->base +
> > + DDRC_PERF_CNT_START_OP_CTRL);
> > +}
> > +
> > +static void cn10k_ddr_perf_pmu_disable(struct pmu *pmu)
> > +{
> > + struct cn10k_ddr_pmu *ddr_pmu = to_cn10k_ddr_pmu(pmu);
> > +
> > + writeq_relaxed(END_OP_CTRL_VAL_END, ddr_pmu->base +
> > + DDRC_PERF_CNT_END_OP_CTRL);
> > +}
> > +
> > +static int cn10k_ddr_perf_probe(struct platform_device *pdev)
> > +{
> > + struct cn10k_ddr_pmu *ddr_pmu;
> > + struct resource *res;
> > + void __iomem *base;
> > + static int index;
> > + char *name;
> > + int ret;
> > +
> > + ddr_pmu = devm_kzalloc(&pdev->dev, sizeof(*ddr_pmu), GFP_KERNEL);
> > + if (!ddr_pmu)
> > + return -ENOMEM;
> > +
> > + ddr_pmu->dev = &pdev->dev;
> > + platform_set_drvdata(pdev, ddr_pmu);
> > +
> > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > + base = devm_ioremap_resource(&pdev->dev, res);
> > + if (IS_ERR(base))
> > + return PTR_ERR(base);
>
> can you use devm_platform_get_and_ioremap_resource()? I think that there
> is some helper that does both these steps
Yes, devm_platform_get_and_ioremap_resource() does both.
>
> > +
> > + ddr_pmu->base = base;
> > +
> > + /* Setup the PMU counter to work in mannual mode */
>
> manual
>
> > + writeq_relaxed(OP_MODE_CTRL_VAL_MANNUAL, ddr_pmu->base +
> > + DDRC_PERF_CNT_OP_MODE_CTRL);
> > +
> > + ddr_pmu->pmu = (struct pmu) {
> > + .module = THIS_MODULE,
> > + .capabilities = PERF_PMU_CAP_NO_EXCLUDE,
> > + .task_ctx_nr = perf_invalid_context,
> > + .attr_groups = cn10k_attr_groups,
> > + .event_init = cn10k_ddr_perf_event_init,
> > + .add = cn10k_ddr_perf_event_add,
> > + .del = cn10k_ddr_perf_event_del,
> > + .start = cn10k_ddr_perf_event_start,
> > + .stop = cn10k_ddr_perf_event_stop,
> > + .read = cn10k_ddr_perf_event_update,
> > + .pmu_enable = cn10k_ddr_perf_pmu_enable,
> > + .pmu_disable = cn10k_ddr_perf_pmu_disable,
> > + };
> > +
> > + /* Choose this cpu to collect perf data */
> > + ddr_pmu->cpu = raw_smp_processor_id();
> > +
> > + name = devm_kasprintf(ddr_pmu->dev, GFP_KERNEL,
> "mrvl_ddr_pmu@%llx",
>
> mostly _%llx would be used elsewhere, and I am not sure how perf tool
> likes @ at all
Will be consistent with other,
>
> > + res->start);
> > + if (!name)
> > + return -ENOMEM;
> > +
> > + ret = perf_pmu_register(&ddr_pmu->pmu, name, -1);
> > + if (ret)
> > + return ret;
> > +
> > + ddr_pmu->id = index++;
>
> where is this used?
Just below to keep count of number of instance.
Thanks for review, will do required changes in next version.
Thanks
-Bharat
>
> > + pr_info("CN10K DDR PMU Driver for ddrc@%llx - id-%d\n",
> > + res->start, ddr_pmu->id);
> > + return 0;
> > +}
> > +
> > +static int cn10k_ddr_perf_remove(struct platform_device *pdev)
> > +{
> > + struct cn10k_ddr_pmu *ddr_pmu = platform_get_drvdata(pdev);
> > +
> > + perf_pmu_unregister(&ddr_pmu->pmu);
> > + return 0;
> > +}
> > +
> > +static const struct of_device_id cn10k_ddr_pmu_of_match[] = {
> > + { .compatible = "marvell,cn10k-ddr-pmu", },
> > + { },
> > +};
> > +MODULE_DEVICE_TABLE(of, cn10k_ddr_pmu_of_match);
> > +
> > +static struct platform_driver cn10k_ddr_pmu_driver = {
> > + .driver = {
> > + .name = "cn10k-ddr-pmu",
> > + .of_match_table = cn10k_ddr_pmu_of_match,
> > + .suppress_bind_attrs = true,
> > + },
> > + .probe = cn10k_ddr_perf_probe,
> > + .remove = cn10k_ddr_perf_remove,
> > +};
> > +
> > +static int __init cn10k_ddr_pmu_init(void)
> > +{
> > + return platform_driver_register(&cn10k_ddr_pmu_driver);
> > +}
> > +
> > +static void __exit cn10k_ddr_pmu_exit(void)
> > +{
> > + platform_driver_unregister(&cn10k_ddr_pmu_driver);
> > +}
> > +
> > +module_init(cn10k_ddr_pmu_init);
> > +module_exit(cn10k_ddr_pmu_exit);
> > +
> > +MODULE_AUTHOR("Bharat Bhushan <bbhushan2@xxxxxxxxxxx>");
> > +MODULE_LICENSE("GPL v2");
> >
