// 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 #include #include #include #include #include #include #include #include #include #include #include PMU_FORMAT_ATTR(event, "config:0-47"); PMU_FORMAT_ATTR(firmware, "config:63"); static struct attribute *riscv_arch_formats_attr[] = { &format_attr_event.attr, &format_attr_firmware.attr, NULL, }; static struct attribute_group riscv_pmu_format_group = { .name = "format", .attrs = riscv_arch_formats_attr, }; static const struct attribute_group *riscv_pmu_attr_groups[] = { &riscv_pmu_format_group, NULL, }; /* * 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; static bool riscv_pmu_use_irq; static unsigned int riscv_pmu_irq_num; static unsigned int riscv_pmu_irq; 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; 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 */ #if defined(CONFIG_32BIT) ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_CFG_MATCH, cbase, rvpmu->cmask, cflags, hwc->event_base, hwc->config, hwc->config >> 32); #else ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_CFG_MATCH, cbase, rvpmu->cmask, cflags, hwc->event_base, hwc->config, 0); #endif 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 (!test_bit(idx, &rvpmu->cmask) || !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; #if defined(CONFIG_32BIT) ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, hwc->idx, 1, flag, ival, ival >> 32, 0); #else ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, hwc->idx, 1, flag, ival, 0, 0); #endif 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, unsigned long *mask) { 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; *mask |= BIT(i); 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 inline void pmu_sbi_stop_all(struct riscv_pmu *pmu) { /* * No need to check the error because we are disabling all the counters * which may include counters that are not enabled yet. */ sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_STOP, 0, pmu->cmask, 0, 0, 0, 0); } static inline void pmu_sbi_stop_hw_ctrs(struct riscv_pmu *pmu) { struct cpu_hw_events *cpu_hw_evt = this_cpu_ptr(pmu->hw_events); /* No need to check the error here as we can't do anything about the error */ sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_STOP, 0, cpu_hw_evt->used_hw_ctrs[0], 0, 0, 0, 0); } /* * This function starts all the used counters in two step approach. * Any counter that did not overflow can be start in a single step * while the overflowed counters need to be started with updated initialization * value. */ static inline void pmu_sbi_start_overflow_mask(struct riscv_pmu *pmu, unsigned long ctr_ovf_mask) { int idx = 0; struct cpu_hw_events *cpu_hw_evt = this_cpu_ptr(pmu->hw_events); struct perf_event *event; unsigned long flag = SBI_PMU_START_FLAG_SET_INIT_VALUE; unsigned long ctr_start_mask = 0; uint64_t max_period; struct hw_perf_event *hwc; u64 init_val = 0; ctr_start_mask = cpu_hw_evt->used_hw_ctrs[0] & ~ctr_ovf_mask; /* Start all the counters that did not overflow in a single shot */ sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, 0, ctr_start_mask, 0, 0, 0, 0); /* Reinitialize and start all the counter that overflowed */ while (ctr_ovf_mask) { if (ctr_ovf_mask & 0x01) { event = cpu_hw_evt->events[idx]; hwc = &event->hw; max_period = riscv_pmu_ctr_get_width_mask(event); init_val = local64_read(&hwc->prev_count) & max_period; #if defined(CONFIG_32BIT) sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, idx, 1, flag, init_val, init_val >> 32, 0); #else sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, idx, 1, flag, init_val, 0, 0); #endif perf_event_update_userpage(event); } ctr_ovf_mask = ctr_ovf_mask >> 1; idx++; } } static irqreturn_t pmu_sbi_ovf_handler(int irq, void *dev) { struct perf_sample_data data; struct pt_regs *regs; struct hw_perf_event *hw_evt; union sbi_pmu_ctr_info *info; int lidx, hidx, fidx; struct riscv_pmu *pmu; struct perf_event *event; unsigned long overflow; unsigned long overflowed_ctrs = 0; struct cpu_hw_events *cpu_hw_evt = dev; u64 start_clock = sched_clock(); if (WARN_ON_ONCE(!cpu_hw_evt)) return IRQ_NONE; /* Firmware counter don't support overflow yet */ fidx = find_first_bit(cpu_hw_evt->used_hw_ctrs, RISCV_MAX_COUNTERS); event = cpu_hw_evt->events[fidx]; if (!event) { csr_clear(CSR_SIP, BIT(riscv_pmu_irq_num)); return IRQ_NONE; } pmu = to_riscv_pmu(event->pmu); pmu_sbi_stop_hw_ctrs(pmu); /* Overflow status register should only be read after counter are stopped */ ALT_SBI_PMU_OVERFLOW(overflow); /* * Overflow interrupt pending bit should only be cleared after stopping * all the counters to avoid any race condition. */ csr_clear(CSR_SIP, BIT(riscv_pmu_irq_num)); /* No overflow bit is set */ if (!overflow) return IRQ_NONE; regs = get_irq_regs(); for_each_set_bit(lidx, cpu_hw_evt->used_hw_ctrs, RISCV_MAX_COUNTERS) { struct perf_event *event = cpu_hw_evt->events[lidx]; /* Skip if invalid event or user did not request a sampling */ if (!event || !is_sampling_event(event)) continue; info = &pmu_ctr_list[lidx]; /* Do a sanity check */ if (!info || info->type != SBI_PMU_CTR_TYPE_HW) continue; /* compute hardware counter index */ hidx = info->csr - CSR_CYCLE; /* check if the corresponding bit is set in sscountovf */ if (!(overflow & (1 << hidx))) continue; /* * Keep a track of overflowed counters so that they can be started * with updated initial value. */ overflowed_ctrs |= 1 << lidx; hw_evt = &event->hw; riscv_pmu_event_update(event); perf_sample_data_init(&data, 0, hw_evt->last_period); if (riscv_pmu_event_set_period(event)) { /* * Unlike other ISAs, RISC-V don't have to disable interrupts * to avoid throttling here. As per the specification, the * interrupt remains disabled until the OF bit is set. * Interrupts are enabled again only during the start. * TODO: We will need to stop the guest counters once * virtualization support is added. */ perf_event_overflow(event, &data, regs); } } pmu_sbi_start_overflow_mask(pmu, overflowed_ctrs); perf_sample_event_took(sched_clock() - start_clock); return IRQ_HANDLED; } 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); struct cpu_hw_events *cpu_hw_evt = this_cpu_ptr(pmu->hw_events); /* * Enable the access for CYCLE, TIME, and INSTRET CSRs from userspace, * as is necessary to maintain uABI compatibility. */ csr_write(CSR_SCOUNTEREN, 0x7); /* Stop all the counters so that they can be enabled from perf */ pmu_sbi_stop_all(pmu); if (riscv_pmu_use_irq) { cpu_hw_evt->irq = riscv_pmu_irq; csr_clear(CSR_IP, BIT(riscv_pmu_irq_num)); csr_set(CSR_IE, BIT(riscv_pmu_irq_num)); enable_percpu_irq(riscv_pmu_irq, IRQ_TYPE_NONE); } return 0; } static int pmu_sbi_dying_cpu(unsigned int cpu, struct hlist_node *node) { if (riscv_pmu_use_irq) { disable_percpu_irq(riscv_pmu_irq); csr_clear(CSR_IE, BIT(riscv_pmu_irq_num)); } /* Disable all counters access for user mode now */ csr_write(CSR_SCOUNTEREN, 0x0); return 0; } static int pmu_sbi_setup_irqs(struct riscv_pmu *pmu, struct platform_device *pdev) { int ret; struct cpu_hw_events __percpu *hw_events = pmu->hw_events; struct device_node *cpu, *child; struct irq_domain *domain = NULL; if (riscv_isa_extension_available(NULL, SSCOFPMF)) { riscv_pmu_irq_num = RV_IRQ_PMU; riscv_pmu_use_irq = true; } else if (IS_ENABLED(CONFIG_ERRATA_THEAD_PMU) && riscv_cached_mvendorid(0) == THEAD_VENDOR_ID && riscv_cached_marchid(0) == 0 && riscv_cached_mimpid(0) == 0) { riscv_pmu_irq_num = THEAD_C9XX_RV_IRQ_PMU; riscv_pmu_use_irq = true; } if (!riscv_pmu_use_irq) return -EOPNOTSUPP; for_each_of_cpu_node(cpu) { child = of_get_compatible_child(cpu, "riscv,cpu-intc"); if (!child) { pr_err("Failed to find INTC node\n"); of_node_put(cpu); return -ENODEV; } domain = irq_find_host(child); of_node_put(child); if (domain) { of_node_put(cpu); break; } } if (!domain) { pr_err("Failed to find INTC IRQ root domain\n"); return -ENODEV; } riscv_pmu_irq = irq_create_mapping(domain, riscv_pmu_irq_num); if (!riscv_pmu_irq) { pr_err("Failed to map PMU interrupt for node\n"); return -ENODEV; } ret = request_percpu_irq(riscv_pmu_irq, pmu_sbi_ovf_handler, "riscv-pmu", hw_events); if (ret) { pr_err("registering percpu irq failed [%d]\n", ret); return ret; } return 0; } #ifdef CONFIG_CPU_PM static int riscv_pm_pmu_notify(struct notifier_block *b, unsigned long cmd, void *v) { struct riscv_pmu *rvpmu = container_of(b, struct riscv_pmu, riscv_pm_nb); struct cpu_hw_events *cpuc = this_cpu_ptr(rvpmu->hw_events); int enabled = bitmap_weight(cpuc->used_hw_ctrs, RISCV_MAX_COUNTERS); struct perf_event *event; int idx; if (!enabled) return NOTIFY_OK; for (idx = 0; idx < RISCV_MAX_COUNTERS; idx++) { event = cpuc->events[idx]; if (!event) continue; switch (cmd) { case CPU_PM_ENTER: /* * Stop and update the counter */ riscv_pmu_stop(event, PERF_EF_UPDATE); break; case CPU_PM_EXIT: case CPU_PM_ENTER_FAILED: /* * Restore and enable the counter. * * Requires RCU read locking to be functional, * wrap the call within RCU_NONIDLE to make the * RCU subsystem aware this cpu is not idle from * an RCU perspective for the riscv_pmu_start() call * duration. */ RCU_NONIDLE(riscv_pmu_start(event, PERF_EF_RELOAD)); break; default: break; } } return NOTIFY_OK; } static int riscv_pm_pmu_register(struct riscv_pmu *pmu) { pmu->riscv_pm_nb.notifier_call = riscv_pm_pmu_notify; return cpu_pm_register_notifier(&pmu->riscv_pm_nb); } static void riscv_pm_pmu_unregister(struct riscv_pmu *pmu) { cpu_pm_unregister_notifier(&pmu->riscv_pm_nb); } #else static inline int riscv_pm_pmu_register(struct riscv_pmu *pmu) { return 0; } static inline void riscv_pm_pmu_unregister(struct riscv_pmu *pmu) { } #endif static void riscv_pmu_destroy(struct riscv_pmu *pmu) { riscv_pm_pmu_unregister(pmu); cpuhp_state_remove_instance(CPUHP_AP_PERF_RISCV_STARTING, &pmu->node); } static int pmu_sbi_device_probe(struct platform_device *pdev) { struct riscv_pmu *pmu = NULL; unsigned long cmask = 0; int ret = -ENODEV; int num_counters; 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"); goto out_free; } /* cache all the information about counters now */ if (pmu_sbi_get_ctrinfo(num_counters, &cmask)) goto out_free; ret = pmu_sbi_setup_irqs(pmu, pdev); if (ret < 0) { pr_info("Perf sampling/filtering is not supported as sscof extension is not available\n"); pmu->pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT; pmu->pmu.capabilities |= PERF_PMU_CAP_NO_EXCLUDE; } pmu->pmu.attr_groups = riscv_pmu_attr_groups; pmu->cmask = cmask; 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 = riscv_pm_pmu_register(pmu); if (ret) goto out_unregister; ret = perf_pmu_register(&pmu->pmu, "cpu", PERF_TYPE_RAW); if (ret) goto out_unregister; return 0; out_unregister: riscv_pmu_destroy(pmu); out_free: kfree(pmu); return ret; } 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)