[PATCH v6 4/4] perf: arm_cspmu: ampere_cspmu: Add support for Ampere SoC PMU

From: Ilkka Koskinen
Date: Tue Aug 15 2023 - 02:37:51 EST

Ampere SoC PMU follows CoreSight PMU architecture. It uses implementation
specific registers to filter events rather than PMEVFILTnR registers.

Signed-off-by: Ilkka Koskinen <ilkka@xxxxxxxxxxxxxxxxxxxxxx>
---
.../admin-guide/perf/ampere_cspmu.rst | 29 ++
drivers/perf/arm_cspmu/Kconfig | 10 +
drivers/perf/arm_cspmu/Makefile | 2 +
drivers/perf/arm_cspmu/ampere_cspmu.c | 271 ++++++++++++++++++
drivers/perf/arm_cspmu/arm_cspmu.c | 8 +
drivers/perf/arm_cspmu/arm_cspmu.h | 1 +
6 files changed, 321 insertions(+)
create mode 100644 Documentation/admin-guide/perf/ampere_cspmu.rst
create mode 100644 drivers/perf/arm_cspmu/ampere_cspmu.c

diff --git a/Documentation/admin-guide/perf/ampere_cspmu.rst b/Documentation/admin-guide/perf/ampere_cspmu.rst
new file mode 100644
index 000000000000..94f93f5aee6c
--- /dev/null
+++ b/Documentation/admin-guide/perf/ampere_cspmu.rst
@@ -0,0 +1,29 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+============================================
+Ampere SoC Performance Monitoring Unit (PMU)
+============================================
+
+Ampere SoC PMU is a generic PMU IP that follows Arm CoreSight PMU architecture.
+Therefore, the driver is implemented as a submodule of arm_cspmu driver. At the
+first phase it's used for counting MCU events on AmpereOne.
+
+
+MCU PMU events
+--------------
+
+The PMU driver supports setting filters for "rank", "bank", and "threshold".
+Note, that the filters are per PMU instance rather than per event.
+
+
+Example for perf tool use::
+
+ / # perf list ampere
+
+ ampere_mcu_pmu_0/act_sent/ [Kernel PMU event]
+ <...>
+ ampere_mcu_pmu_1/rd_sent/ [Kernel PMU event]
+ <...>
+
+ / # perf stat -a -e ampere_mcu_pmu_0/act_sent,bank=5,rank=3,threshold=2/,ampere_mcu_pmu_1/rd_sent/ \
+ sleep 1
diff --git a/drivers/perf/arm_cspmu/Kconfig b/drivers/perf/arm_cspmu/Kconfig
index d5f787d22234..6f4e28fc84a2 100644
--- a/drivers/perf/arm_cspmu/Kconfig
+++ b/drivers/perf/arm_cspmu/Kconfig
@@ -17,3 +17,13 @@ config NVIDIA_CORESIGHT_PMU_ARCH_SYSTEM_PMU
help
Provides NVIDIA specific attributes for performance monitoring unit
(PMU) devices based on ARM CoreSight PMU architecture.
+
+config AMPERE_CORESIGHT_PMU_ARCH_SYSTEM_PMU
+ tristate "Ampere Coresight Architecture PMU"
+ depends on ARM_CORESIGHT_PMU_ARCH_SYSTEM_PMU
+ help
+ Provides Ampere specific attributes for performance monitoring unit
+ (PMU) devices based on ARM CoreSight PMU architecture.
+
+ In the first phase, the driver enables support on MCU PMU used in
+ AmpereOne SoC family.
diff --git a/drivers/perf/arm_cspmu/Makefile b/drivers/perf/arm_cspmu/Makefile
index 0309d2ff264a..220a734efd54 100644
--- a/drivers/perf/arm_cspmu/Makefile
+++ b/drivers/perf/arm_cspmu/Makefile
@@ -3,6 +3,8 @@
# SPDX-License-Identifier: GPL-2.0

obj-$(CONFIG_ARM_CORESIGHT_PMU_ARCH_SYSTEM_PMU) += arm_cspmu_module.o
+
arm_cspmu_module-y := arm_cspmu.o

obj-$(CONFIG_NVIDIA_CORESIGHT_PMU_ARCH_SYSTEM_PMU) += nvidia_cspmu.o
+obj-$(CONFIG_AMPERE_CORESIGHT_PMU_ARCH_SYSTEM_PMU) += ampere_cspmu.o
diff --git a/drivers/perf/arm_cspmu/ampere_cspmu.c b/drivers/perf/arm_cspmu/ampere_cspmu.c
new file mode 100644
index 000000000000..a365f59fbfe7
--- /dev/null
+++ b/drivers/perf/arm_cspmu/ampere_cspmu.c
@@ -0,0 +1,271 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Ampere SoC PMU (Performance Monitor Unit)
+ *
+ * Copyright (c) 2023, Ampere Computing LLC
+ */
+#include <linux/module.h>
+#include <linux/topology.h>
+
+#include "arm_cspmu.h"
+
+#define PMAUXR0 0xD80
+#define PMAUXR1 0xD84
+#define PMAUXR2 0xD88
+#define PMAUXR3 0xD8C
+
+#define to_ampere_cspmu_ctx(cspmu) ((struct ampere_cspmu_ctx *)(cspmu->impl.ctx))
+
+struct ampere_cspmu_ctx {
+ const char *name;
+ struct attribute **event_attr;
+ struct attribute **format_attr;
+};
+
+static DEFINE_IDR(mcu_pmu_idr);
+
+#define SOC_PMU_EVENT_ATTR_EXTRACTOR(_name, _config, _start, _end) \
+ static inline u32 get_##_name(const struct perf_event *event) \
+ { \
+ return FIELD_GET(GENMASK_ULL(_end, _start), \
+ event->attr._config); \
+ } \
+
+SOC_PMU_EVENT_ATTR_EXTRACTOR(event, config, 0, 8);
+SOC_PMU_EVENT_ATTR_EXTRACTOR(threshold, config1, 0, 7);
+SOC_PMU_EVENT_ATTR_EXTRACTOR(rank, config1, 8, 23);
+SOC_PMU_EVENT_ATTR_EXTRACTOR(bank, config1, 24, 55);
+
+static struct attribute *ampereone_mcu_pmu_event_attrs[] = {
+ ARM_CSPMU_EVENT_ATTR(cycle_count, 0x00),
+ ARM_CSPMU_EVENT_ATTR(act_sent, 0x01),
+ ARM_CSPMU_EVENT_ATTR(pre_sent, 0x02),
+ ARM_CSPMU_EVENT_ATTR(rd_sent, 0x03),
+ ARM_CSPMU_EVENT_ATTR(rda_sent, 0x04),
+ ARM_CSPMU_EVENT_ATTR(wr_sent, 0x05),
+ ARM_CSPMU_EVENT_ATTR(wra_sent, 0x06),
+ ARM_CSPMU_EVENT_ATTR(pd_entry_vld, 0x07),
+ ARM_CSPMU_EVENT_ATTR(sref_entry_vld, 0x08),
+ ARM_CSPMU_EVENT_ATTR(prea_sent, 0x09),
+ ARM_CSPMU_EVENT_ATTR(pre_sb_sent, 0x0a),
+ ARM_CSPMU_EVENT_ATTR(ref_sent, 0x0b),
+ ARM_CSPMU_EVENT_ATTR(rfm_sent, 0x0c),
+ ARM_CSPMU_EVENT_ATTR(ref_sb_sent, 0x0d),
+ ARM_CSPMU_EVENT_ATTR(rfm_sb_sent, 0x0e),
+ ARM_CSPMU_EVENT_ATTR(rd_rda_sent, 0x0f),
+ ARM_CSPMU_EVENT_ATTR(wr_wra_sent, 0x10),
+ ARM_CSPMU_EVENT_ATTR(raw_hazard, 0x11),
+ ARM_CSPMU_EVENT_ATTR(war_hazard, 0x12),
+ ARM_CSPMU_EVENT_ATTR(waw_hazard, 0x13),
+ ARM_CSPMU_EVENT_ATTR(rar_hazard, 0x14),
+ ARM_CSPMU_EVENT_ATTR(raw_war_waw_hazard, 0x15),
+ ARM_CSPMU_EVENT_ATTR(hprd_lprd_wr_req_vld, 0x16),
+ ARM_CSPMU_EVENT_ATTR(lprd_req_vld, 0x17),
+ ARM_CSPMU_EVENT_ATTR(hprd_req_vld, 0x18),
+ ARM_CSPMU_EVENT_ATTR(hprd_lprd_req_vld, 0x19),
+ ARM_CSPMU_EVENT_ATTR(prefetch_tgt, 0x1a),
+ ARM_CSPMU_EVENT_ATTR(wr_req_vld, 0x1b),
+ ARM_CSPMU_EVENT_ATTR(partial_wr_req_vld, 0x1c),
+ ARM_CSPMU_EVENT_ATTR(rd_retry, 0x1d),
+ ARM_CSPMU_EVENT_ATTR(wr_retry, 0x1e),
+ ARM_CSPMU_EVENT_ATTR(retry_gnt, 0x1f),
+ ARM_CSPMU_EVENT_ATTR(rank_change, 0x20),
+ ARM_CSPMU_EVENT_ATTR(dir_change, 0x21),
+ ARM_CSPMU_EVENT_ATTR(rank_dir_change, 0x22),
+ ARM_CSPMU_EVENT_ATTR(rank_active, 0x23),
+ ARM_CSPMU_EVENT_ATTR(rank_idle, 0x24),
+ ARM_CSPMU_EVENT_ATTR(rank_pd, 0x25),
+ ARM_CSPMU_EVENT_ATTR(rank_sref, 0x26),
+ ARM_CSPMU_EVENT_ATTR(queue_fill_gt_thresh, 0x27),
+ ARM_CSPMU_EVENT_ATTR(queue_rds_gt_thresh, 0x28),
+ ARM_CSPMU_EVENT_ATTR(queue_wrs_gt_thresh, 0x29),
+ ARM_CSPMU_EVENT_ATTR(phy_updt_complt, 0x2a),
+ ARM_CSPMU_EVENT_ATTR(tz_fail, 0x2b),
+ ARM_CSPMU_EVENT_ATTR(dram_errc, 0x2c),
+ ARM_CSPMU_EVENT_ATTR(dram_errd, 0x2d),
+ ARM_CSPMU_EVENT_ATTR(read_data_return, 0x32),
+ ARM_CSPMU_EVENT_ATTR(chi_wr_data_delta, 0x33),
+ ARM_CSPMU_EVENT_ATTR(zq_start, 0x34),
+ ARM_CSPMU_EVENT_ATTR(zq_latch, 0x35),
+ ARM_CSPMU_EVENT_ATTR(wr_fifo_full, 0x36),
+ ARM_CSPMU_EVENT_ATTR(info_fifo_full, 0x37),
+ ARM_CSPMU_EVENT_ATTR(cmd_fifo_full, 0x38),
+ ARM_CSPMU_EVENT_ATTR(dfi_nop, 0x39),
+ ARM_CSPMU_EVENT_ATTR(dfi_cmd, 0x3a),
+ ARM_CSPMU_EVENT_ATTR(rd_run_len, 0x3b),
+ ARM_CSPMU_EVENT_ATTR(wr_run_len, 0x3c),
+
+ ARM_CSPMU_EVENT_ATTR(cycles, ARM_CSPMU_EVT_CYCLES_DEFAULT),
+ NULL,
+};
+
+static struct attribute *ampereone_mcu_format_attrs[] = {
+ ARM_CSPMU_FORMAT_EVENT_ATTR,
+ ARM_CSPMU_FORMAT_ATTR(threshold, "config1:0-7"),
+ ARM_CSPMU_FORMAT_ATTR(rank, "config1:8-23"),
+ ARM_CSPMU_FORMAT_ATTR(bank, "config1:24-55"),
+ NULL,
+};
+
+static struct attribute **
+ampere_cspmu_get_event_attrs(const struct arm_cspmu *cspmu)
+{
+ const struct ampere_cspmu_ctx *ctx = to_ampere_cspmu_ctx(cspmu);
+
+ return ctx->event_attr;
+}
+
+static struct attribute **
+ampere_cspmu_get_format_attrs(const struct arm_cspmu *cspmu)
+{
+ const struct ampere_cspmu_ctx *ctx = to_ampere_cspmu_ctx(cspmu);
+
+ return ctx->format_attr;
+}
+
+static const char *
+ampere_cspmu_get_name(const struct arm_cspmu *cspmu)
+{
+ const struct ampere_cspmu_ctx *ctx = to_ampere_cspmu_ctx(cspmu);
+
+ return ctx->name;
+}
+
+static u32 ampere_cspmu_event_filter(const struct perf_event *event)
+{
+ /*
+ * PMEVFILTR or PMCCFILTR aren't used in Ampere SoC PMU but are marked
+ * as RES0. Make sure, PMCCFILTR is written zero.
+ */
+ return 0;
+}
+
+static void ampere_cspmu_set_ev_filter(struct arm_cspmu *cspmu,
+ struct hw_perf_event *hwc,
+ u32 filter)
+{
+ struct perf_event *event;
+ unsigned int idx;
+ u32 threshold, rank, bank;
+
+ /*
+ * At this point, all the events have the same filter settings.
+ * Therefore, take the first event and use its configuration.
+ */
+ idx = find_first_bit(cspmu->hw_events.used_ctrs,
+ cspmu->cycle_counter_logical_idx);
+
+ event = cspmu->hw_events.events[idx];
+
+ threshold = get_threshold(event);
+ rank = get_rank(event);
+ bank = get_bank(event);
+
+ writel(threshold, cspmu->base0 + PMAUXR0);
+ writel(rank, cspmu->base0 + PMAUXR1);
+ writel(bank, cspmu->base0 + PMAUXR2);
+}
+
+static int ampere_cspmu_validate_configs(struct perf_event *event,
+ struct perf_event *event2)
+{
+ if (get_threshold(event) != get_threshold(event2) ||
+ get_rank(event) != get_rank(event2) ||
+ get_bank(event) != get_bank(event2))
+ return -EINVAL;
+
+ return 0;
+}
+
+static int ampere_cspmu_validate_event(struct arm_cspmu *cspmu,
+ struct perf_event *new)
+{
+ struct perf_event *curr, *leader = new->group_leader;
+ unsigned int idx;
+ int ret;
+
+ ret = ampere_cspmu_validate_configs(new, leader);
+ if (ret)
+ return ret;
+
+ /* We compare the global filter settings to the existing events */
+ idx = find_first_bit(cspmu->hw_events.used_ctrs,
+ cspmu->cycle_counter_logical_idx);
+
+ /* This is the first event, thus any configuration is fine */
+ if (idx == cspmu->cycle_counter_logical_idx)
+ return 0;
+
+ curr = cspmu->hw_events.events[idx];
+
+ return ampere_cspmu_validate_configs(curr, new);
+}
+
+static char *ampere_cspmu_format_name(const struct arm_cspmu *cspmu,
+ const char *name_pattern)
+{
+ struct device *dev = cspmu->dev;
+ int id;
+
+ id = idr_alloc(&mcu_pmu_idr, NULL, 0, 0, GFP_KERNEL);
+ if (id < 0)
+ return ERR_PTR(id);
+
+ return devm_kasprintf(dev, GFP_KERNEL, name_pattern, id);
+}
+
+static int ampere_cspmu_init_ops(struct arm_cspmu *cspmu)
+{
+ struct device *dev = cspmu->dev;
+ struct ampere_cspmu_ctx *ctx;
+ struct arm_cspmu_impl_ops *impl_ops = &cspmu->impl.ops;
+
+ ctx = devm_kzalloc(dev, sizeof(struct ampere_cspmu_ctx), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ ctx->event_attr = ampereone_mcu_pmu_event_attrs;
+ ctx->format_attr = ampereone_mcu_format_attrs;
+ ctx->name = ampere_cspmu_format_name(cspmu, "ampere_mcu_pmu_%d");
+ if (IS_ERR_OR_NULL(ctx->name))
+ return ctx->name ? PTR_ERR(ctx->name) : -ENOMEM;
+
+ cspmu->impl.ctx = ctx;
+
+ impl_ops->event_filter = ampere_cspmu_event_filter;
+ impl_ops->set_ev_filter = ampere_cspmu_set_ev_filter;
+ impl_ops->validate_event = ampere_cspmu_validate_event;
+ impl_ops->get_name = ampere_cspmu_get_name;
+ impl_ops->get_event_attrs = ampere_cspmu_get_event_attrs;
+ impl_ops->get_format_attrs = ampere_cspmu_get_format_attrs;
+
+ return 0;
+}
+
+/* Match all Ampere Coresight PMU devices */
+static const struct arm_cspmu_impl_match ampere_cspmu_param = {
+ .pmiidr_val = ARM_CSPMU_IMPL_ID_AMPERE,
+ .module = THIS_MODULE,
+ .impl_init_ops = ampere_cspmu_init_ops
+};
+
+static int __init ampere_cspmu_init(void)
+{
+ int ret;
+
+ ret = arm_cspmu_impl_register(&ampere_cspmu_param);
+ if (ret)
+ pr_err("ampere_cspmu backend registration error: %d\n", ret);
+
+ return ret;
+}
+
+static void __exit ampere_cspmu_exit(void)
+{
+ arm_cspmu_impl_unregister(&ampere_cspmu_param);
+}
+
+module_init(ampere_cspmu_init);
+module_exit(ampere_cspmu_exit);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c
index 585ce96ac03f..d6c50e06c5bc 100644
--- a/drivers/perf/arm_cspmu/arm_cspmu.c
+++ b/drivers/perf/arm_cspmu/arm_cspmu.c
@@ -383,6 +383,14 @@ static struct arm_cspmu_impl_match impl_match[] = {
.module = NULL,
.impl_init_ops = NULL,
},
+ {
+ .module_name = "ampere_cspmu",
+ .pmiidr_val = ARM_CSPMU_IMPL_ID_AMPERE,
+ .pmiidr_mask = ARM_CSPMU_PMIIDR_IMPLEMENTER,
+ .module = NULL,
+ .impl_init_ops = NULL,
+ },
+
{0}
};

diff --git a/drivers/perf/arm_cspmu/arm_cspmu.h b/drivers/perf/arm_cspmu/arm_cspmu.h
index 05577f74b8a0..586441d4dba1 100644
--- a/drivers/perf/arm_cspmu/arm_cspmu.h
+++ b/drivers/perf/arm_cspmu/arm_cspmu.h
@@ -71,6 +71,7 @@

/* JEDEC-assigned JEP106 identification code */
#define ARM_CSPMU_IMPL_ID_NVIDIA 0x36B
+#define ARM_CSPMU_IMPL_ID_AMPERE 0xA16

struct arm_cspmu;

--
2.41.0