diff options
author | Atish Patra <atish.patra@wdc.com> | 2022-02-18 16:46:57 -0800 |
---|---|---|
committer | Palmer Dabbelt <palmer@rivosinc.com> | 2022-03-21 14:58:33 -0700 |
commit | e9991434596f5373dfd75857b445eb92a9253c56 (patch) | |
tree | b39e3c364207841faf568f86332c8a087b8fe622 | |
parent | 90beae5185c260074db409241247630036cf93a0 (diff) |
RISC-V: Add perf platform driver based on SBI PMU extension
RISC-V SBI specification added a PMU extension that allows to configure
start/stop any pmu counter. The RISC-V perf can use most of the generic
perf features except interrupt overflow and event filtering based on
privilege mode which will be added in future.
It also allows to monitor a handful of firmware counters that can provide
insights into firmware activity during a performance analysis.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
-rw-r--r-- | drivers/perf/Kconfig | 10 | ||||
-rw-r--r-- | drivers/perf/Makefile | 1 | ||||
-rw-r--r-- | drivers/perf/riscv_pmu.c | 2 | ||||
-rw-r--r-- | drivers/perf/riscv_pmu_sbi.c | 578 | ||||
-rw-r--r-- | include/linux/cpuhotplug.h | 1 | ||||
-rw-r--r-- | include/linux/perf/riscv_pmu.h | 6 |
6 files changed, 596 insertions, 2 deletions
diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig index 386162ad858a..5645b5615c14 100644 --- a/drivers/perf/Kconfig +++ b/drivers/perf/Kconfig @@ -76,6 +76,16 @@ config RISCV_PMU_LEGACY of cycle/instruction counter and doesn't support counter overflow, or programmable counters. It will be removed in future. +config RISCV_PMU_SBI + depends on RISCV_PMU && RISCV_SBI + bool "RISC-V PMU based on SBI PMU extension" + default y + help + Say y if you want to use the CPU performance monitor + using SBI PMU extension on RISC-V based systems. This option provides + full perf feature support i.e. counter overflow, privilege mode + filtering, counter configuration. + config ARM_PMU_ACPI depends on ARM_PMU && ACPI def_bool y diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile index c3d3268d495b..f149735166e1 100644 --- a/drivers/perf/Makefile +++ b/drivers/perf/Makefile @@ -12,6 +12,7 @@ obj-$(CONFIG_QCOM_L2_PMU) += qcom_l2_pmu.o obj-$(CONFIG_QCOM_L3_PMU) += qcom_l3_pmu.o obj-$(CONFIG_RISCV_PMU) += riscv_pmu.o obj-$(CONFIG_RISCV_PMU_LEGACY) += riscv_pmu_legacy.o +obj-$(CONFIG_RISCV_PMU_SBI) += riscv_pmu_sbi.o obj-$(CONFIG_THUNDERX2_PMU) += thunderx2_pmu.o obj-$(CONFIG_XGENE_PMU) += xgene_pmu.o obj-$(CONFIG_ARM_SPE_PMU) += arm_spe_pmu.o diff --git a/drivers/perf/riscv_pmu.c b/drivers/perf/riscv_pmu.c index 590a5789c128..b2b8d2074ed0 100644 --- a/drivers/perf/riscv_pmu.c +++ b/drivers/perf/riscv_pmu.c @@ -15,6 +15,8 @@ #include <linux/printk.h> #include <linux/smp.h> +#include <asm/sbi.h> + static unsigned long csr_read_num(int csr_num) { #define switchcase_csr_read(__csr_num, __val) {\ diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c new file mode 100644 index 000000000000..815d5c509c64 --- /dev/null +++ b/drivers/perf/riscv_pmu_sbi.c @@ -0,0 +1,578 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * RISC-V performance counter support. + * + * Copyright (C) 2021 Western Digital Corporation or its affiliates. + * + * This code is based on ARM perf event code which is in turn based on + * sparc64 and x86 code. + */ + +#define pr_fmt(fmt) "riscv-pmu-sbi: " fmt + +#include <linux/mod_devicetable.h> +#include <linux/perf/riscv_pmu.h> +#include <linux/platform_device.h> + +#include <asm/sbi.h> + +union sbi_pmu_ctr_info { + unsigned long value; + struct { + unsigned long csr:12; + unsigned long width:6; +#if __riscv_xlen == 32 + unsigned long reserved:13; +#else + unsigned long reserved:45; +#endif + unsigned long type:1; + }; +}; + +/** + * RISC-V doesn't have hetergenous harts yet. This need to be part of + * per_cpu in case of harts with different pmu counters + */ +static union sbi_pmu_ctr_info *pmu_ctr_list; + +struct sbi_pmu_event_data { + union { + union { + struct hw_gen_event { + uint32_t event_code:16; + uint32_t event_type:4; + uint32_t reserved:12; + } hw_gen_event; + struct hw_cache_event { + uint32_t result_id:1; + uint32_t op_id:2; + uint32_t cache_id:13; + uint32_t event_type:4; + uint32_t reserved:12; + } hw_cache_event; + }; + uint32_t event_idx; + }; +}; + +static const struct sbi_pmu_event_data pmu_hw_event_map[] = { + [PERF_COUNT_HW_CPU_CYCLES] = {.hw_gen_event = { + SBI_PMU_HW_CPU_CYCLES, + SBI_PMU_EVENT_TYPE_HW, 0}}, + [PERF_COUNT_HW_INSTRUCTIONS] = {.hw_gen_event = { + SBI_PMU_HW_INSTRUCTIONS, + SBI_PMU_EVENT_TYPE_HW, 0}}, + [PERF_COUNT_HW_CACHE_REFERENCES] = {.hw_gen_event = { + SBI_PMU_HW_CACHE_REFERENCES, + SBI_PMU_EVENT_TYPE_HW, 0}}, + [PERF_COUNT_HW_CACHE_MISSES] = {.hw_gen_event = { + SBI_PMU_HW_CACHE_MISSES, + SBI_PMU_EVENT_TYPE_HW, 0}}, + [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = {.hw_gen_event = { + SBI_PMU_HW_BRANCH_INSTRUCTIONS, + SBI_PMU_EVENT_TYPE_HW, 0}}, + [PERF_COUNT_HW_BRANCH_MISSES] = {.hw_gen_event = { + SBI_PMU_HW_BRANCH_MISSES, + SBI_PMU_EVENT_TYPE_HW, 0}}, + [PERF_COUNT_HW_BUS_CYCLES] = {.hw_gen_event = { + SBI_PMU_HW_BUS_CYCLES, + SBI_PMU_EVENT_TYPE_HW, 0}}, + [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = {.hw_gen_event = { + SBI_PMU_HW_STALLED_CYCLES_FRONTEND, + SBI_PMU_EVENT_TYPE_HW, 0}}, + [PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = {.hw_gen_event = { + SBI_PMU_HW_STALLED_CYCLES_BACKEND, + SBI_PMU_EVENT_TYPE_HW, 0}}, + [PERF_COUNT_HW_REF_CPU_CYCLES] = {.hw_gen_event = { + SBI_PMU_HW_REF_CPU_CYCLES, + SBI_PMU_EVENT_TYPE_HW, 0}}, +}; + +#define C(x) PERF_COUNT_HW_CACHE_##x +static const struct sbi_pmu_event_data pmu_cache_event_map[PERF_COUNT_HW_CACHE_MAX] +[PERF_COUNT_HW_CACHE_OP_MAX] +[PERF_COUNT_HW_CACHE_RESULT_MAX] = { + [C(L1D)] = { + [C(OP_READ)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_READ), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_READ), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_WRITE)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_WRITE), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_WRITE), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_PREFETCH)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_PREFETCH), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_PREFETCH), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + }, + [C(L1I)] = { + [C(OP_READ)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_READ), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), C(OP_READ), + C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_WRITE)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_WRITE), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_WRITE), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_PREFETCH)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_PREFETCH), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_PREFETCH), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + }, + [C(LL)] = { + [C(OP_READ)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_READ), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_READ), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_WRITE)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_WRITE), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_WRITE), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_PREFETCH)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_PREFETCH), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_PREFETCH), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + }, + [C(DTLB)] = { + [C(OP_READ)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_READ), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_READ), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_WRITE)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_WRITE), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_WRITE), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_PREFETCH)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_PREFETCH), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_PREFETCH), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + }, + [C(ITLB)] = { + [C(OP_READ)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_READ), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_READ), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_WRITE)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_WRITE), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_WRITE), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_PREFETCH)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_PREFETCH), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_PREFETCH), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + }, + [C(BPU)] = { + [C(OP_READ)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_READ), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_READ), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_WRITE)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_WRITE), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_WRITE), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_PREFETCH)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_PREFETCH), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_PREFETCH), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + }, + [C(NODE)] = { + [C(OP_READ)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_READ), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_READ), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_WRITE)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_WRITE), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_WRITE), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + [C(OP_PREFETCH)] = { + [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), + C(OP_PREFETCH), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), + C(OP_PREFETCH), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}}, + }, + }, +}; + +static int pmu_sbi_ctr_get_width(int idx) +{ + return pmu_ctr_list[idx].width; +} + +static bool pmu_sbi_ctr_is_fw(int cidx) +{ + union sbi_pmu_ctr_info *info; + + info = &pmu_ctr_list[cidx]; + if (!info) + return false; + + return (info->type == SBI_PMU_CTR_TYPE_FW) ? true : false; +} + +static int pmu_sbi_ctr_get_idx(struct perf_event *event) +{ + struct hw_perf_event *hwc = &event->hw; + struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu); + struct cpu_hw_events *cpuc = this_cpu_ptr(rvpmu->hw_events); + struct sbiret ret; + int idx; + uint64_t cbase = 0; + uint64_t cmask = GENMASK_ULL(rvpmu->num_counters - 1, 0); + unsigned long cflags = 0; + + if (event->attr.exclude_kernel) + cflags |= SBI_PMU_CFG_FLAG_SET_SINH; + if (event->attr.exclude_user) + cflags |= SBI_PMU_CFG_FLAG_SET_UINH; + + /* retrieve the available counter index */ + ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_CFG_MATCH, cbase, cmask, + cflags, hwc->event_base, hwc->config, 0); + if (ret.error) { + pr_debug("Not able to find a counter for event %lx config %llx\n", + hwc->event_base, hwc->config); + return sbi_err_map_linux_errno(ret.error); + } + + idx = ret.value; + if (idx >= rvpmu->num_counters || !pmu_ctr_list[idx].value) + return -ENOENT; + + /* Additional sanity check for the counter id */ + if (pmu_sbi_ctr_is_fw(idx)) { + if (!test_and_set_bit(idx, cpuc->used_fw_ctrs)) + return idx; + } else { + if (!test_and_set_bit(idx, cpuc->used_hw_ctrs)) + return idx; + } + + return -ENOENT; +} + +static void pmu_sbi_ctr_clear_idx(struct perf_event *event) +{ + + struct hw_perf_event *hwc = &event->hw; + struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu); + struct cpu_hw_events *cpuc = this_cpu_ptr(rvpmu->hw_events); + int idx = hwc->idx; + + if (pmu_sbi_ctr_is_fw(idx)) + clear_bit(idx, cpuc->used_fw_ctrs); + else + clear_bit(idx, cpuc->used_hw_ctrs); +} + +static int pmu_event_find_cache(u64 config) +{ + unsigned int cache_type, cache_op, cache_result, ret; + + cache_type = (config >> 0) & 0xff; + if (cache_type >= PERF_COUNT_HW_CACHE_MAX) + return -EINVAL; + + cache_op = (config >> 8) & 0xff; + if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX) + return -EINVAL; + + cache_result = (config >> 16) & 0xff; + if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX) + return -EINVAL; + + ret = pmu_cache_event_map[cache_type][cache_op][cache_result].event_idx; + + return ret; +} + +static bool pmu_sbi_is_fw_event(struct perf_event *event) +{ + u32 type = event->attr.type; + u64 config = event->attr.config; + + if ((type == PERF_TYPE_RAW) && ((config >> 63) == 1)) + return true; + else + return false; +} + +static int pmu_sbi_event_map(struct perf_event *event, u64 *econfig) +{ + u32 type = event->attr.type; + u64 config = event->attr.config; + int bSoftware; + u64 raw_config_val; + int ret; + + switch (type) { + case PERF_TYPE_HARDWARE: + if (config >= PERF_COUNT_HW_MAX) + return -EINVAL; + ret = pmu_hw_event_map[event->attr.config].event_idx; + break; + case PERF_TYPE_HW_CACHE: + ret = pmu_event_find_cache(config); + break; + case PERF_TYPE_RAW: + /* + * As per SBI specification, the upper 16 bits must be unused for + * a raw event. Use the MSB (63b) to distinguish between hardware + * raw event and firmware events. + */ + bSoftware = config >> 63; + raw_config_val = config & RISCV_PMU_RAW_EVENT_MASK; + if (bSoftware) { + if (raw_config_val < SBI_PMU_FW_MAX) + ret = (raw_config_val & 0xFFFF) | + (SBI_PMU_EVENT_TYPE_FW << 16); + else + return -EINVAL; + } else { + ret = RISCV_PMU_RAW_EVENT_IDX; + *econfig = raw_config_val; + } + break; + default: + ret = -EINVAL; + break; + } + + return ret; +} + +static u64 pmu_sbi_ctr_read(struct perf_event *event) +{ + struct hw_perf_event *hwc = &event->hw; + int idx = hwc->idx; + struct sbiret ret; + union sbi_pmu_ctr_info info; + u64 val = 0; + + if (pmu_sbi_is_fw_event(event)) { + ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_FW_READ, + hwc->idx, 0, 0, 0, 0, 0); + if (!ret.error) + val = ret.value; + } else { + info = pmu_ctr_list[idx]; + val = riscv_pmu_ctr_read_csr(info.csr); + if (IS_ENABLED(CONFIG_32BIT)) + val = ((u64)riscv_pmu_ctr_read_csr(info.csr + 0x80)) << 31 | val; + } + + return val; +} + +static void pmu_sbi_ctr_start(struct perf_event *event, u64 ival) +{ + struct sbiret ret; + struct hw_perf_event *hwc = &event->hw; + unsigned long flag = SBI_PMU_START_FLAG_SET_INIT_VALUE; + + ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, hwc->idx, + 1, flag, ival, ival >> 32, 0); + if (ret.error && (ret.error != SBI_ERR_ALREADY_STARTED)) + pr_err("Starting counter idx %d failed with error %d\n", + hwc->idx, sbi_err_map_linux_errno(ret.error)); +} + +static void pmu_sbi_ctr_stop(struct perf_event *event, unsigned long flag) +{ + struct sbiret ret; + struct hw_perf_event *hwc = &event->hw; + + ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_STOP, hwc->idx, 1, flag, 0, 0, 0); + if (ret.error && (ret.error != SBI_ERR_ALREADY_STOPPED) && + flag != SBI_PMU_STOP_FLAG_RESET) + pr_err("Stopping counter idx %d failed with error %d\n", + hwc->idx, sbi_err_map_linux_errno(ret.error)); +} + +static int pmu_sbi_find_num_ctrs(void) +{ + struct sbiret ret; + + ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_NUM_COUNTERS, 0, 0, 0, 0, 0, 0); + if (!ret.error) + return ret.value; + else + return sbi_err_map_linux_errno(ret.error); +} + +static int pmu_sbi_get_ctrinfo(int nctr) +{ + struct sbiret ret; + int i, num_hw_ctr = 0, num_fw_ctr = 0; + union sbi_pmu_ctr_info cinfo; + + pmu_ctr_list = kcalloc(nctr, sizeof(*pmu_ctr_list), GFP_KERNEL); + if (!pmu_ctr_list) + return -ENOMEM; + + for (i = 0; i <= nctr; i++) { + ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_GET_INFO, i, 0, 0, 0, 0, 0); + if (ret.error) + /* The logical counter ids are not expected to be contiguous */ + continue; + cinfo.value = ret.value; + if (cinfo.type == SBI_PMU_CTR_TYPE_FW) + num_fw_ctr++; + else + num_hw_ctr++; + pmu_ctr_list[i].value = cinfo.value; + } + + pr_info("%d firmware and %d hardware counters\n", num_fw_ctr, num_hw_ctr); + + return 0; +} + +static int pmu_sbi_starting_cpu(unsigned int cpu, struct hlist_node *node) +{ + struct riscv_pmu *pmu = hlist_entry_safe(node, struct riscv_pmu, node); + + /* Enable the access for TIME csr only from the user mode now */ + csr_write(CSR_SCOUNTEREN, 0x2); + + /* Stop all the counters so that they can be enabled from perf */ + sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_STOP, + 0, GENMASK_ULL(pmu->num_counters - 1, 0), 0, 0, 0, 0); + + return 0; +} + +static int pmu_sbi_dying_cpu(unsigned int cpu, struct hlist_node *node) +{ + /* Disable all counters access for user mode now */ + csr_write(CSR_SCOUNTEREN, 0x0); + + return 0; +} + +static int pmu_sbi_device_probe(struct platform_device *pdev) +{ + struct riscv_pmu *pmu = NULL; + int num_counters; + int ret; + + pr_info("SBI PMU extension is available\n"); + pmu = riscv_pmu_alloc(); + if (!pmu) + return -ENOMEM; + + num_counters = pmu_sbi_find_num_ctrs(); + if (num_counters < 0) { + pr_err("SBI PMU extension doesn't provide any counters\n"); + return -ENODEV; + } + + /* cache all the information about counters now */ + if (pmu_sbi_get_ctrinfo(num_counters)) + return -ENODEV; + + pmu->num_counters = num_counters; + pmu->ctr_start = pmu_sbi_ctr_start; + pmu->ctr_stop = pmu_sbi_ctr_stop; + pmu->event_map = pmu_sbi_event_map; + pmu->ctr_get_idx = pmu_sbi_ctr_get_idx; + pmu->ctr_get_width = pmu_sbi_ctr_get_width; + pmu->ctr_clear_idx = pmu_sbi_ctr_clear_idx; + pmu->ctr_read = pmu_sbi_ctr_read; + + ret = cpuhp_state_add_instance(CPUHP_AP_PERF_RISCV_STARTING, &pmu->node); + if (ret) + return ret; + + ret = perf_pmu_register(&pmu->pmu, "cpu", PERF_TYPE_RAW); + if (ret) { + cpuhp_state_remove_instance(CPUHP_AP_PERF_RISCV_STARTING, &pmu->node); + return ret; + } + + return 0; +} + +static struct platform_driver pmu_sbi_driver = { + .probe = pmu_sbi_device_probe, + .driver = { + .name = RISCV_PMU_PDEV_NAME, + }, +}; + +static int __init pmu_sbi_devinit(void) +{ + int ret; + struct platform_device *pdev; + + if (sbi_spec_version < sbi_mk_version(0, 3) || + sbi_probe_extension(SBI_EXT_PMU) <= 0) { + return 0; + } + + ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_RISCV_STARTING, + "perf/riscv/pmu:starting", + pmu_sbi_starting_cpu, pmu_sbi_dying_cpu); + if (ret) { + pr_err("CPU hotplug notifier could not be registered: %d\n", + ret); + return ret; + } + + ret = platform_driver_register(&pmu_sbi_driver); + if (ret) + return ret; + + pdev = platform_device_register_simple(RISCV_PMU_PDEV_NAME, -1, NULL, 0); + if (IS_ERR(pdev)) { + platform_driver_unregister(&pmu_sbi_driver); + return PTR_ERR(pdev); + } + + /* Notify legacy implementation that SBI pmu is available*/ + riscv_pmu_legacy_skip_init(); + + return ret; +} +device_initcall(pmu_sbi_devinit) diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 411a428ace4d..51c7e4929df7 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -165,6 +165,7 @@ enum cpuhp_state { CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING, CPUHP_AP_PERF_ARM_ACPI_STARTING, CPUHP_AP_PERF_ARM_STARTING, + CPUHP_AP_PERF_RISCV_STARTING, CPUHP_AP_ARM_L2X0_STARTING, CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING, CPUHP_AP_ARM_ARCH_TIMER_STARTING, diff --git a/include/linux/perf/riscv_pmu.h b/include/linux/perf/riscv_pmu.h index 9140c491fc54..0f226948c0ca 100644 --- a/include/linux/perf/riscv_pmu.h +++ b/include/linux/perf/riscv_pmu.h @@ -31,8 +31,10 @@ struct cpu_hw_events { int n_events; /* currently enabled events */ struct perf_event *events[RISCV_MAX_COUNTERS]; - /* currently enabled counters */ - DECLARE_BITMAP(used_event_ctrs, RISCV_MAX_COUNTERS); + /* currently enabled hardware counters */ + DECLARE_BITMAP(used_hw_ctrs, RISCV_MAX_COUNTERS); + /* currently enabled firmware counters */ + DECLARE_BITMAP(used_fw_ctrs, RISCV_MAX_COUNTERS); }; struct riscv_pmu { |