Re: [PATCH v3 2/2] drivers/perf: hisi: Add Support for CPA PMU

From: John Garry
Date: Tue Apr 05 2022 - 06:26:33 EST


On 21/03/2022 07:01, Qi Liu wrote:
On HiSilicon Hip09 platform, there is a CPA(Coherency Protocol Agent) on

leave whitespace before '('

each SICL (Super I/O Cluster) which implements packet format translation,
route parsing and traffic statistic.

statistics


CPA PMU has 8 PMU counters and interrupt is supported to handle counter
overflow. Let's support its driver under the framework of HiSilicon PMU
driver.


Generally this looks ok, just some small comments to consider.

Thanks,
John

Signed-off-by: Qi Liu <liuqi115@xxxxxxxxxx>
---
drivers/perf/hisilicon/Makefile | 2 +-
drivers/perf/hisilicon/hisi_uncore_cpa_pmu.c | 400 +++++++++++++++++++
include/linux/cpuhotplug.h | 1 +
3 files changed, 402 insertions(+), 1 deletion(-)
create mode 100644 drivers/perf/hisilicon/hisi_uncore_cpa_pmu.c

diff --git a/drivers/perf/hisilicon/Makefile b/drivers/perf/hisilicon/Makefile
index 506ed39e3266..6be83517acaa 100644
--- a/drivers/perf/hisilicon/Makefile
+++ b/drivers/perf/hisilicon/Makefile
@@ -1,6 +1,6 @@
# SPDX-License-Identifier: GPL-2.0-only
obj-$(CONFIG_HISI_PMU) += hisi_uncore_pmu.o hisi_uncore_l3c_pmu.o \
hisi_uncore_hha_pmu.o hisi_uncore_ddrc_pmu.o hisi_uncore_sllc_pmu.o \
- hisi_uncore_pa_pmu.o
+ hisi_uncore_pa_pmu.o hisi_uncore_cpa_pmu.o
obj-$(CONFIG_HISI_PCIE_PMU) += hisi_pcie_pmu.o
diff --git a/drivers/perf/hisilicon/hisi_uncore_cpa_pmu.c b/drivers/perf/hisilicon/hisi_uncore_cpa_pmu.c
new file mode 100644
index 000000000000..3f1d9c3f99fe
--- /dev/null
+++ b/drivers/perf/hisilicon/hisi_uncore_cpa_pmu.c
@@ -0,0 +1,400 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * HiSilicon SoC CPA(Coherency Protocol Agent) uncore hardware event counters support

I am not sure why we even mention uncore for something which is not in a SCCL

+ *
+ * Copyright (C) 2022 HiSilicon Limited
+ * Author: Qi Liu <liuqi115@xxxxxxxxxx>
+ *
+ * This code is based on the uncore PMUs like arm-cci and arm-ccn.
+ */
+
+#include <linux/acpi.h>
+#include <linux/bug.h>
+#include <linux/cpuhotplug.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/list.h>
+#include <linux/smp.h>
+
+#include "hisi_uncore_pmu.h"
+
+/* CPA register definition */
+#define CPA_PERF_CTRL 0x1c00
+#define CPA_EVENT_CTRL 0x1c04
+#define CPA_INT_MASK 0x1c70
+#define CPA_INT_STATUS 0x1c78
+#define CPA_INT_CLEAR 0x1c7c
+#define CPA_EVENT_TYPE0 0x1c80
+#define CPA_VERSION 0x1cf0
+#define CPA_CNT0_LOWER 0x1d00
+#define CPA_CFG_REG 0x0534
+
+/* CPA operation command */
+#define CPA_PERF_CTRL_EN BIT_ULL(0)
+#define CPA_EVTYPE_MASK 0xffUL
+#define CPA_PM_CTRL BIT_ULL(9)
+
+/* CPA has 8-counters */
+#define CPA_NR_COUNTERS 0x8
+#define CPA_COUNTER_BITS 64
+#define CPA_NR_EVENTS 0xff
+#define CPA_REG_OFFSET 0x8
+
+static u32 hisi_cpa_pmu_get_counter_offset(int idx)
+{
+ return (CPA_CNT0_LOWER + idx * CPA_REG_OFFSET);
+}
+
+static u64 hisi_cpa_pmu_read_counter(struct hisi_pmu *cpa_pmu,
+ struct hw_perf_event *hwc)
+{
+ return readq(cpa_pmu->base + hisi_cpa_pmu_get_counter_offset(hwc->idx));
+}
+
+static void hisi_cpa_pmu_write_counter(struct hisi_pmu *cpa_pmu,
+ struct hw_perf_event *hwc, u64 val)
+{
+ writeq(val, cpa_pmu->base + hisi_cpa_pmu_get_counter_offset(hwc->idx));
+}
+
+static void hisi_cpa_pmu_write_evtype(struct hisi_pmu *cpa_pmu, int idx, u32 type)
+{
+ u32 reg, reg_idx, shift, val;
+
+ /*
+ * Select the appropriate event select register(CPA_EVENT_TYPE0/1).
+ * There are 2 event select registers for the 8 hardware counters.
+ * Event code is 8-bits and for the former 4 hardware counters,
+ * CPA_EVENT_TYPE0 is chosen. For the latter 4 hardware counters,
+ * CPA_EVENT_TYPE1 is chosen.
+ */
+ reg = CPA_EVENT_TYPE0 + (idx / 4) * 4;
+ reg_idx = idx % 4;
+ shift = CPA_REG_OFFSET * reg_idx;
+
+ /* Write event code to CPA_EVENT_TYPEx Register */
+ val = readl(cpa_pmu->base + reg);
+ val &= ~(CPA_EVTYPE_MASK << shift);
+ val |= type << shift;
+ writel(val, cpa_pmu->base + reg);
+}
+
+static void hisi_cpa_pmu_start_counters(struct hisi_pmu *cpa_pmu)
+{
+ u32 val;
+
+ val = readl(cpa_pmu->base + CPA_PERF_CTRL);
+ val |= CPA_PERF_CTRL_EN;
+ writel(val, cpa_pmu->base + CPA_PERF_CTRL);
+}
+
+static void hisi_cpa_pmu_stop_counters(struct hisi_pmu *cpa_pmu)
+{
+ u32 val;
+
+ val = readl(cpa_pmu->base + CPA_PERF_CTRL);
+ val &= ~(CPA_PERF_CTRL_EN);
+ writel(val, cpa_pmu->base + CPA_PERF_CTRL);
+}
+
+static void hisi_cpa_pmu_disable_pm(struct hisi_pmu *cpa_pmu)
+{
+ u32 val;
+
+ val = readl(cpa_pmu->base + CPA_CFG_REG);
+ val |= CPA_PM_CTRL;
+ writel(val, cpa_pmu->base + CPA_CFG_REG);
+}
+
+static void hisi_cpa_pmu_enable_pm(struct hisi_pmu *cpa_pmu)
+{
+ u32 val;
+
+ val = readl(cpa_pmu->base + CPA_CFG_REG);
+ val &= ~(CPA_PM_CTRL);
+ writel(val, cpa_pmu->base + CPA_CFG_REG);
+}
+
+static void hisi_cpa_pmu_enable_counter(struct hisi_pmu *cpa_pmu, struct hw_perf_event *hwc)
+{
+ u32 val;
+
+ /* Enable counter index in CPA_EVENT_CTRL register */
+ val = readl(cpa_pmu->base + CPA_EVENT_CTRL);
+ val |= 1 << hwc->idx;
+ writel(val, cpa_pmu->base + CPA_EVENT_CTRL);
+}
+
+static void hisi_cpa_pmu_disable_counter(struct hisi_pmu *cpa_pmu, struct hw_perf_event *hwc)
+{
+ u32 val;
+
+ /* Clear counter index in CPA_EVENT_CTRL register */
+ val = readl(cpa_pmu->base + CPA_EVENT_CTRL);
+ val &= ~(1UL << hwc->idx);
+ writel(val, cpa_pmu->base + CPA_EVENT_CTRL);
+}
+
+static void hisi_cpa_pmu_enable_counter_int(struct hisi_pmu *cpa_pmu, struct hw_perf_event *hwc)
+{
+ u32 val;
+
+ /* Write 0 to enable interrupt */
+ val = readl(cpa_pmu->base + CPA_INT_MASK);
+ val &= ~(1UL << hwc->idx);
+ writel(val, cpa_pmu->base + CPA_INT_MASK);
+}
+
+static void hisi_cpa_pmu_disable_counter_int(struct hisi_pmu *cpa_pmu, struct hw_perf_event *hwc)
+{
+ u32 val;
+
+ /* Write 1 to mask interrupt */
+ val = readl(cpa_pmu->base + CPA_INT_MASK);
+ val |= 1 << hwc->idx;
+ writel(val, cpa_pmu->base + CPA_INT_MASK);
+}
+
+static u32 hisi_cpa_pmu_get_int_status(struct hisi_pmu *cpa_pmu)
+{
+ return readl(cpa_pmu->base + CPA_INT_STATUS);
+}
+
+static void hisi_cpa_pmu_clear_int_status(struct hisi_pmu *cpa_pmu, int idx)
+{
+ writel(1 << idx, cpa_pmu->base + CPA_INT_CLEAR);
+}
+
+static const struct acpi_device_id hisi_cpa_pmu_acpi_match[] = {
+ { "HISI0281", },
+ {}
+};
+MODULE_DEVICE_TABLE(acpi, hisi_cpa_pmu_acpi_match);
+
+static int hisi_cpa_pmu_init_data(struct platform_device *pdev,
+ struct hisi_pmu *cpa_pmu)
+{
+ if (device_property_read_u32(&pdev->dev, "hisilicon,scl-id",
+ &cpa_pmu->sicl_id)) {
+ dev_err(&pdev->dev, "Can not read cpa_pmu sicl-id\n");

I don't think that you need to mention "cpa_pmu"

+ return -EINVAL;
+ }
+
+ if (device_property_read_u32(&pdev->dev, "hisilicon,idx-id",
+ &cpa_pmu->index_id)) {
+ dev_err(&pdev->dev, "Cannot read idx-id\n");
+ return -EINVAL;
+ }
+
+ cpa_pmu->ccl_id = -1;
+ cpa_pmu->sccl_id = -1;
+ cpa_pmu->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(cpa_pmu->base))
+ return PTR_ERR(cpa_pmu->base);
+
+ cpa_pmu->identifier = readl(cpa_pmu->base + CPA_VERSION);
+
+ return 0;
+}
+
+static struct attribute *hisi_cpa_pmu_format_attr[] = {
+ HISI_PMU_FORMAT_ATTR(event, "config:0-15"),
+ NULL
+};
+
+static const struct attribute_group hisi_cpa_pmu_format_group = {
+ .name = "format",
+ .attrs = hisi_cpa_pmu_format_attr,
+};
+
+static struct attribute *hisi_cpa_pmu_events_attr[] = {
+ HISI_PMU_EVENT_ATTR(cpa_cycles, 0x00),
+ HISI_PMU_EVENT_ATTR(cpa_p1_wr_dat, 0x61),
+ HISI_PMU_EVENT_ATTR(cpa_p1_rd_dat, 0x62),
+ HISI_PMU_EVENT_ATTR(cpa_p0_wr_dat, 0xE1),
+ HISI_PMU_EVENT_ATTR(cpa_p0_rd_dat, 0xE2),
+ NULL
+};
+
+static const struct attribute_group hisi_cpa_pmu_events_group = {
+ .name = "events",
+ .attrs = hisi_cpa_pmu_events_attr,
+};
+
+static DEVICE_ATTR(cpumask, 0444, hisi_cpumask_sysfs_show, NULL);
+
+static struct attribute *hisi_cpa_pmu_cpumask_attrs[] = {
+ &dev_attr_cpumask.attr,
+ NULL
+};
+
+static const struct attribute_group hisi_cpa_pmu_cpumask_attr_group = {
+ .attrs = hisi_cpa_pmu_cpumask_attrs,
+};
+
+static struct device_attribute hisi_cpa_pmu_identifier_attr =
+ __ATTR(identifier, 0444, hisi_uncore_pmu_identifier_attr_show, NULL);
+
+static struct attribute *hisi_cpa_pmu_identifier_attrs[] = {
+ &hisi_cpa_pmu_identifier_attr.attr,
+ NULL
+};
+
+static const struct attribute_group hisi_cpa_pmu_identifier_group = {
+ .attrs = hisi_cpa_pmu_identifier_attrs,
+};
+
+static const struct attribute_group *hisi_cpa_pmu_attr_groups[] = {
+ &hisi_cpa_pmu_format_group,
+ &hisi_cpa_pmu_events_group,
+ &hisi_cpa_pmu_cpumask_attr_group,
+ &hisi_cpa_pmu_identifier_group,
+ NULL
+};
+
+static const struct hisi_uncore_ops hisi_uncore_cpa_pmu_ops = {
+ .write_evtype = hisi_cpa_pmu_write_evtype,
+ .get_event_idx = hisi_uncore_pmu_get_event_idx,
+ .start_counters = hisi_cpa_pmu_start_counters,
+ .stop_counters = hisi_cpa_pmu_stop_counters,
+ .enable_counter = hisi_cpa_pmu_enable_counter,
+ .disable_counter = hisi_cpa_pmu_disable_counter,
+ .enable_counter_int = hisi_cpa_pmu_enable_counter_int,
+ .disable_counter_int = hisi_cpa_pmu_disable_counter_int,
+ .write_counter = hisi_cpa_pmu_write_counter,
+ .read_counter = hisi_cpa_pmu_read_counter,
+ .get_int_status = hisi_cpa_pmu_get_int_status,
+ .clear_int_status = hisi_cpa_pmu_clear_int_status,
+};
+
+static int hisi_cpa_pmu_dev_probe(struct platform_device *pdev,
+ struct hisi_pmu *cpa_pmu)
+{
+ int ret;
+
+ ret = hisi_cpa_pmu_init_data(pdev, cpa_pmu);
+ if (ret)
+ return ret;
+
+ ret = hisi_uncore_pmu_init_irq(cpa_pmu, pdev);
+ if (ret)
+ return ret;
+
+ cpa_pmu->counter_bits = CPA_COUNTER_BITS;
+ cpa_pmu->check_event = CPA_NR_EVENTS;
+ cpa_pmu->pmu_events.attr_groups = hisi_cpa_pmu_attr_groups;
+ cpa_pmu->ops = &hisi_uncore_cpa_pmu_ops;
+ cpa_pmu->num_counters = CPA_NR_COUNTERS;
+ cpa_pmu->dev = &pdev->dev;
+ cpa_pmu->on_cpu = -1;
+
+ return 0;
+}
+
+static int hisi_cpa_pmu_probe(struct platform_device *pdev)
+{
+ struct hisi_pmu *cpa_pmu;
+ char *name;
+ int ret;
+
+ cpa_pmu = devm_kzalloc(&pdev->dev, sizeof(*cpa_pmu), GFP_KERNEL);
+ if (!cpa_pmu)
+ return -ENOMEM;
+
+ ret = hisi_cpa_pmu_dev_probe(pdev, cpa_pmu);
+ if (ret)
+ return ret;
+
+ ret = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_HISI_CPA_ONLINE,
+ &cpa_pmu->node);
+ if (ret) {
+ dev_err(&pdev->dev, "Error %d registering hotplug\n", ret);
+ return ret;
+ }
+
+ name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "hisi_sicl%d_cpa%u", cpa_pmu->sicl_id,
+ cpa_pmu->index_id);
+
+ cpa_pmu->pmu = (struct pmu) {
+ .name = name,
+ .module = THIS_MODULE,
+ .task_ctx_nr = perf_invalid_context,
+ .event_init = hisi_uncore_pmu_event_init,
+ .pmu_enable = hisi_uncore_pmu_enable,
+ .pmu_disable = hisi_uncore_pmu_disable,
+ .add = hisi_uncore_pmu_add,
+ .del = hisi_uncore_pmu_del,
+ .start = hisi_uncore_pmu_start,
+ .stop = hisi_uncore_pmu_stop,
+ .read = hisi_uncore_pmu_read,
+ .attr_groups = cpa_pmu->pmu_events.attr_groups,
+ .capabilities = PERF_PMU_CAP_NO_EXCLUDE,
+ };
+
+ ret = perf_pmu_register(&cpa_pmu->pmu, name, -1);
+ if (ret) {
+ dev_err(cpa_pmu->dev, "PMU register failed\n");
+ cpuhp_state_remove_instance_nocalls(
+ CPUHP_AP_PERF_ARM_HISI_CPA_ONLINE, &cpa_pmu->node);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, cpa_pmu);
+
+ /* Power Management should be disabled before using CPA PMU. */
+ hisi_cpa_pmu_disable_pm(cpa_pmu);

maybe you can move this earlier in the probe, before registering

+ return ret;
+}
+
+static int hisi_cpa_pmu_remove(struct platform_device *pdev)
+{
+ struct hisi_pmu *cpa_pmu = platform_get_drvdata(pdev);
+
+ hisi_cpa_pmu_enable_pm(cpa_pmu);

why do we do this?

+ perf_pmu_unregister(&cpa_pmu->pmu);
+ cpuhp_state_remove_instance_nocalls(CPUHP_AP_PERF_ARM_HISI_CPA_ONLINE,
+ &cpa_pmu->node);
+ return 0;
+}
+
+static struct platform_driver hisi_cpa_pmu_driver = {
+ .driver = {
+ .name = "hisi_cpa_pmu",
+ .acpi_match_table = ACPI_PTR(hisi_cpa_pmu_acpi_match),
+ .suppress_bind_attrs = true,
+ },
+ .probe = hisi_cpa_pmu_probe,
+ .remove = hisi_cpa_pmu_remove,
+};
+
+static int __init hisi_cpa_pmu_module_init(void)
+{
+ int ret;
+
+ ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_HISI_CPA_ONLINE,
+ "AP_PERF_ARM_HISI_CPA_ONLINE",
+ hisi_uncore_pmu_online_cpu,
+ hisi_uncore_pmu_offline_cpu);
+ if (ret) {
+ pr_err("CPA PMU: setup hotplug: %d\n", ret);

you don't mention failed

And mostly we use lowercase for the driver name and maybe consider using pr_fmt

+ return ret;
+ }
+
+ ret = platform_driver_register(&hisi_cpa_pmu_driver);
+ if (ret)
+ cpuhp_remove_multi_state(CPUHP_AP_PERF_ARM_HISI_CPA_ONLINE);
+
+ return ret;
+}
+module_init(hisi_cpa_pmu_module_init);
+
+static void __exit hisi_cpa_pmu_module_exit(void)
+{
+ platform_driver_unregister(&hisi_cpa_pmu_driver);
+ cpuhp_remove_multi_state(CPUHP_AP_PERF_ARM_HISI_CPA_ONLINE);
+}
+module_exit(hisi_cpa_pmu_module_exit);
+
+MODULE_DESCRIPTION("HiSilicon SoC CPA uncore PMU driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Qi Liu <liuqi115@xxxxxxxxxx>");
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 411a428ace4d..d55063719904 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -220,6 +220,7 @@ enum cpuhp_state {
CPUHP_AP_PERF_S390_SF_ONLINE,
CPUHP_AP_PERF_ARM_CCI_ONLINE,
CPUHP_AP_PERF_ARM_CCN_ONLINE,
+ CPUHP_AP_PERF_ARM_HISI_CPA_ONLINE,
CPUHP_AP_PERF_ARM_HISI_DDRC_ONLINE,
CPUHP_AP_PERF_ARM_HISI_HHA_ONLINE,
CPUHP_AP_PERF_ARM_HISI_L3_ONLINE,