diff --git a/Documentation/admin-guide/perf/nvidia-tegra410-pmu.rst b/Documentation/admin-guide/perf/nvidia-tegra410-pmu.rst index 9945c43f6a7a..0656223b61d4 100644 --- a/Documentation/admin-guide/perf/nvidia-tegra410-pmu.rst +++ b/Documentation/admin-guide/perf/nvidia-tegra410-pmu.rst @@ -9,6 +9,9 @@ metrics like memory bandwidth, latency, and utilization: * PCIE * PCIE-TGT * CPU Memory (CMEM) Latency +* NVLink-C2C +* NV-CLink +* NV-DLink PMU Driver ---------- @@ -369,3 +372,151 @@ see /sys/bus/event_source/devices/nvidia_cmem_latency_pmu_. Example usage:: perf stat -a -e '{nvidia_cmem_latency_pmu_0/rd_req/,nvidia_cmem_latency_pmu_0/rd_cum_outs/,nvidia_cmem_latency_pmu_0/cycles/}' + +NVLink-C2C PMU +-------------- + +This PMU monitors latency events of memory read/write requests that pass through +the NVIDIA Chip-to-Chip (C2C) interface. Bandwidth events are not available +in this PMU, unlike the C2C PMU in Grace (Tegra241 SoC). + +The events and configuration options of this PMU device are available in sysfs, +see /sys/bus/event_source/devices/nvidia_nvlink_c2c_pmu_. + +The list of events: + + * IN_RD_CUM_OUTS: accumulated outstanding request (in cycles) of incoming read requests. + * IN_RD_REQ: the number of incoming read requests. + * IN_WR_CUM_OUTS: accumulated outstanding request (in cycles) of incoming write requests. + * IN_WR_REQ: the number of incoming write requests. + * OUT_RD_CUM_OUTS: accumulated outstanding request (in cycles) of outgoing read requests. + * OUT_RD_REQ: the number of outgoing read requests. + * OUT_WR_CUM_OUTS: accumulated outstanding request (in cycles) of outgoing write requests. + * OUT_WR_REQ: the number of outgoing write requests. + * CYCLES: NVLink-C2C interface cycle counts. + +The incoming events count the reads/writes from remote device to the SoC. +The outgoing events count the reads/writes from the SoC to remote device. + +The sysfs /sys/bus/event_source/devices/nvidia_nvlink_c2c_pmu_/peer +contains the information about the connected device. + +When the C2C interface is connected to GPU(s), the user can use the +"gpu_mask" parameter to filter traffic to/from specific GPU(s). Each bit represents the GPU +index, e.g. "gpu_mask=0x1" corresponds to GPU 0 and "gpu_mask=0x3" is for GPU 0 and 1. +The PMU will monitor all GPUs by default if not specified. + +When connected to another SoC, only the read events are available. + +The events can be used to calculate the average latency of the read/write requests:: + + C2C_FREQ_IN_GHZ = CYCLES / ELAPSED_TIME_IN_NS + + IN_RD_AVG_LATENCY_IN_CYCLES = IN_RD_CUM_OUTS / IN_RD_REQ + IN_RD_AVG_LATENCY_IN_NS = IN_RD_AVG_LATENCY_IN_CYCLES / C2C_FREQ_IN_GHZ + + IN_WR_AVG_LATENCY_IN_CYCLES = IN_WR_CUM_OUTS / IN_WR_REQ + IN_WR_AVG_LATENCY_IN_NS = IN_WR_AVG_LATENCY_IN_CYCLES / C2C_FREQ_IN_GHZ + + OUT_RD_AVG_LATENCY_IN_CYCLES = OUT_RD_CUM_OUTS / OUT_RD_REQ + OUT_RD_AVG_LATENCY_IN_NS = OUT_RD_AVG_LATENCY_IN_CYCLES / C2C_FREQ_IN_GHZ + + OUT_WR_AVG_LATENCY_IN_CYCLES = OUT_WR_CUM_OUTS / OUT_WR_REQ + OUT_WR_AVG_LATENCY_IN_NS = OUT_WR_AVG_LATENCY_IN_CYCLES / C2C_FREQ_IN_GHZ + +Example usage: + + * Count incoming traffic from all GPUs connected via NVLink-C2C:: + + perf stat -a -e nvidia_nvlink_c2c_pmu_0/in_rd_req/ + + * Count incoming traffic from GPU 0 connected via NVLink-C2C:: + + perf stat -a -e nvidia_nvlink_c2c_pmu_0/in_rd_cum_outs,gpu_mask=0x1/ + + * Count incoming traffic from GPU 1 connected via NVLink-C2C:: + + perf stat -a -e nvidia_nvlink_c2c_pmu_0/in_rd_cum_outs,gpu_mask=0x2/ + + * Count outgoing traffic to all GPUs connected via NVLink-C2C:: + + perf stat -a -e nvidia_nvlink_c2c_pmu_0/out_rd_req/ + + * Count outgoing traffic to GPU 0 connected via NVLink-C2C:: + + perf stat -a -e nvidia_nvlink_c2c_pmu_0/out_rd_cum_outs,gpu_mask=0x1/ + + * Count outgoing traffic to GPU 1 connected via NVLink-C2C:: + + perf stat -a -e nvidia_nvlink_c2c_pmu_0/out_rd_cum_outs,gpu_mask=0x2/ + +NV-CLink PMU +------------ + +This PMU monitors latency events of memory read requests that pass through +the NV-CLINK interface. Bandwidth events are not available in this PMU. +In Tegra410 SoC, the NV-CLink interface is used to connect to another Tegra410 +SoC and this PMU only counts read traffic. + +The events and configuration options of this PMU device are available in sysfs, +see /sys/bus/event_source/devices/nvidia_nvclink_pmu_. + +The list of events: + + * IN_RD_CUM_OUTS: accumulated outstanding request (in cycles) of incoming read requests. + * IN_RD_REQ: the number of incoming read requests. + * OUT_RD_CUM_OUTS: accumulated outstanding request (in cycles) of outgoing read requests. + * OUT_RD_REQ: the number of outgoing read requests. + * CYCLES: NV-CLINK interface cycle counts. + +The incoming events count the reads from remote device to the SoC. +The outgoing events count the reads from the SoC to remote device. + +The events can be used to calculate the average latency of the read requests:: + + CLINK_FREQ_IN_GHZ = CYCLES / ELAPSED_TIME_IN_NS + + IN_RD_AVG_LATENCY_IN_CYCLES = IN_RD_CUM_OUTS / IN_RD_REQ + IN_RD_AVG_LATENCY_IN_NS = IN_RD_AVG_LATENCY_IN_CYCLES / CLINK_FREQ_IN_GHZ + + OUT_RD_AVG_LATENCY_IN_CYCLES = OUT_RD_CUM_OUTS / OUT_RD_REQ + OUT_RD_AVG_LATENCY_IN_NS = OUT_RD_AVG_LATENCY_IN_CYCLES / CLINK_FREQ_IN_GHZ + +Example usage: + + * Count incoming read traffic from remote SoC connected via NV-CLINK:: + + perf stat -a -e nvidia_nvclink_pmu_0/in_rd_req/ + + * Count outgoing read traffic to remote SoC connected via NV-CLINK:: + + perf stat -a -e nvidia_nvclink_pmu_0/out_rd_req/ + +NV-DLink PMU +------------ + +This PMU monitors latency events of memory read requests that pass through +the NV-DLINK interface. Bandwidth events are not available in this PMU. +In Tegra410 SoC, this PMU only counts CXL memory read traffic. + +The events and configuration options of this PMU device are available in sysfs, +see /sys/bus/event_source/devices/nvidia_nvdlink_pmu_. + +The list of events: + + * IN_RD_CUM_OUTS: accumulated outstanding read requests (in cycles) to CXL memory. + * IN_RD_REQ: the number of read requests to CXL memory. + * CYCLES: NV-DLINK interface cycle counts. + +The events can be used to calculate the average latency of the read requests:: + + DLINK_FREQ_IN_GHZ = CYCLES / ELAPSED_TIME_IN_NS + + IN_RD_AVG_LATENCY_IN_CYCLES = IN_RD_CUM_OUTS / IN_RD_REQ + IN_RD_AVG_LATENCY_IN_NS = IN_RD_AVG_LATENCY_IN_CYCLES / DLINK_FREQ_IN_GHZ + +Example usage: + + * Count read events to CXL memory:: + + perf stat -a -e '{nvidia_nvdlink_pmu_0/in_rd_req/,nvidia_nvdlink_pmu_0/in_rd_cum_outs/}' diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig index 26e86067d8f9..ab90932fc2d0 100644 --- a/drivers/perf/Kconfig +++ b/drivers/perf/Kconfig @@ -318,4 +318,11 @@ config NVIDIA_TEGRA410_CMEM_LATENCY_PMU Enable perf support for CPU memory latency counters monitoring on NVIDIA Tegra410 SoC. +config NVIDIA_TEGRA410_C2C_PMU + tristate "NVIDIA Tegra410 C2C PMU" + depends on ARM64 && ACPI + help + Enable perf support for counters in NVIDIA C2C interface of NVIDIA + Tegra410 SoC. + endmenu diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile index 4aa6aad393c2..eb8a022dad9a 100644 --- a/drivers/perf/Makefile +++ b/drivers/perf/Makefile @@ -36,3 +36,4 @@ obj-$(CONFIG_ARM_CORESIGHT_PMU_ARCH_SYSTEM_PMU) += arm_cspmu/ obj-$(CONFIG_MESON_DDR_PMU) += amlogic/ obj-$(CONFIG_CXL_PMU) += cxl_pmu.o obj-$(CONFIG_NVIDIA_TEGRA410_CMEM_LATENCY_PMU) += nvidia_t410_cmem_latency_pmu.o +obj-$(CONFIG_NVIDIA_TEGRA410_C2C_PMU) += nvidia_t410_c2c_pmu.o diff --git a/drivers/perf/nvidia_t410_c2c_pmu.c b/drivers/perf/nvidia_t410_c2c_pmu.c new file mode 100644 index 000000000000..411987153ff3 --- /dev/null +++ b/drivers/perf/nvidia_t410_c2c_pmu.c @@ -0,0 +1,1051 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * NVIDIA Tegra410 C2C PMU driver. + * + * Copyright (c) 2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* The C2C interface types in Tegra410. */ +#define C2C_TYPE_NVLINK 0x0 +#define C2C_TYPE_NVCLINK 0x1 +#define C2C_TYPE_NVDLINK 0x2 +#define C2C_TYPE_COUNT 0x3 + +/* The type of the peer device connected to the C2C interface. */ +#define C2C_PEER_TYPE_CPU 0x0 +#define C2C_PEER_TYPE_GPU 0x1 +#define C2C_PEER_TYPE_CXLMEM 0x2 +#define C2C_PEER_TYPE_COUNT 0x3 + +/* The number of peer devices can be connected to the C2C interface. */ +#define C2C_NR_PEER_CPU 0x1 +#define C2C_NR_PEER_GPU 0x2 +#define C2C_NR_PEER_CXLMEM 0x1 +#define C2C_NR_PEER_MAX 0x2 + +/* Number of instances on each interface. */ +#define C2C_NR_INST_NVLINK 14 +#define C2C_NR_INST_NVCLINK 12 +#define C2C_NR_INST_NVDLINK 16 +#define C2C_NR_INST_MAX 16 + +/* Register offsets. */ +#define C2C_CTRL 0x864 +#define C2C_IN_STATUS 0x868 +#define C2C_CYCLE_CNTR 0x86c +#define C2C_IN_RD_CUM_OUTS_CNTR 0x874 +#define C2C_IN_RD_REQ_CNTR 0x87c +#define C2C_IN_WR_CUM_OUTS_CNTR 0x884 +#define C2C_IN_WR_REQ_CNTR 0x88c +#define C2C_OUT_STATUS 0x890 +#define C2C_OUT_RD_CUM_OUTS_CNTR 0x898 +#define C2C_OUT_RD_REQ_CNTR 0x8a0 +#define C2C_OUT_WR_CUM_OUTS_CNTR 0x8a8 +#define C2C_OUT_WR_REQ_CNTR 0x8b0 + +/* C2C_IN_STATUS register field. */ +#define C2C_IN_STATUS_CYCLE_OVF BIT(0) +#define C2C_IN_STATUS_IN_RD_CUM_OUTS_OVF BIT(1) +#define C2C_IN_STATUS_IN_RD_REQ_OVF BIT(2) +#define C2C_IN_STATUS_IN_WR_CUM_OUTS_OVF BIT(3) +#define C2C_IN_STATUS_IN_WR_REQ_OVF BIT(4) + +/* C2C_OUT_STATUS register field. */ +#define C2C_OUT_STATUS_OUT_RD_CUM_OUTS_OVF BIT(0) +#define C2C_OUT_STATUS_OUT_RD_REQ_OVF BIT(1) +#define C2C_OUT_STATUS_OUT_WR_CUM_OUTS_OVF BIT(2) +#define C2C_OUT_STATUS_OUT_WR_REQ_OVF BIT(3) + +/* Events. */ +#define C2C_EVENT_CYCLES 0x0 +#define C2C_EVENT_IN_RD_CUM_OUTS 0x1 +#define C2C_EVENT_IN_RD_REQ 0x2 +#define C2C_EVENT_IN_WR_CUM_OUTS 0x3 +#define C2C_EVENT_IN_WR_REQ 0x4 +#define C2C_EVENT_OUT_RD_CUM_OUTS 0x5 +#define C2C_EVENT_OUT_RD_REQ 0x6 +#define C2C_EVENT_OUT_WR_CUM_OUTS 0x7 +#define C2C_EVENT_OUT_WR_REQ 0x8 + +#define C2C_NUM_EVENTS 0x9 +#define C2C_MASK_EVENT 0xFF +#define C2C_MAX_ACTIVE_EVENTS 32 + +#define C2C_ACTIVE_CPU_MASK 0x0 +#define C2C_ASSOCIATED_CPU_MASK 0x1 + +/* + * Maximum poll count for reading counter value using high-low-high sequence. + */ +#define HILOHI_MAX_POLL 1000 + +static unsigned long nv_c2c_pmu_cpuhp_state; + +/* PMU descriptor. */ + +/* C2C type information. */ +struct nv_c2c_pmu_data { + unsigned int c2c_type; + unsigned int nr_inst; + const char *name_fmt; +}; + +static const struct nv_c2c_pmu_data nv_c2c_pmu_data[] = { + [C2C_TYPE_NVLINK] = { + .c2c_type = C2C_TYPE_NVLINK, + .nr_inst = C2C_NR_INST_NVLINK, + .name_fmt = "nvidia_nvlink_c2c_pmu_%u", + }, + [C2C_TYPE_NVCLINK] = { + .c2c_type = C2C_TYPE_NVCLINK, + .nr_inst = C2C_NR_INST_NVCLINK, + .name_fmt = "nvidia_nvclink_pmu_%u", + }, + [C2C_TYPE_NVDLINK] = { + .c2c_type = C2C_TYPE_NVDLINK, + .nr_inst = C2C_NR_INST_NVDLINK, + .name_fmt = "nvidia_nvdlink_pmu_%u", + }, +}; + +/* Tracks the events assigned to the PMU for a given logical index. */ +struct nv_c2c_pmu_hw_events { + /* The events that are active. */ + struct perf_event *events[C2C_MAX_ACTIVE_EVENTS]; + + /* + * Each bit indicates a logical counter is being used (or not) for an + * event. + */ + DECLARE_BITMAP(used_ctrs, C2C_MAX_ACTIVE_EVENTS); +}; + +struct nv_c2c_pmu { + struct pmu pmu; + struct device *dev; + struct acpi_device *acpi_dev; + + const char *name; + const char *identifier; + + const struct nv_c2c_pmu_data *data; + unsigned int peer_type; + unsigned int socket; + unsigned int nr_peer; + unsigned long peer_insts[C2C_NR_PEER_MAX][BITS_TO_LONGS(C2C_NR_INST_MAX)]; + u32 filter_default; + + struct nv_c2c_pmu_hw_events hw_events; + + cpumask_t associated_cpus; + cpumask_t active_cpu; + + struct hlist_node cpuhp_node; + + const struct attribute_group **attr_groups; + + void __iomem *base_broadcast; + void __iomem *base[C2C_NR_INST_MAX]; +}; + +#define to_c2c_pmu(p) (container_of(p, struct nv_c2c_pmu, pmu)) + +/* Get event type from perf_event. */ +static inline u32 get_event_type(struct perf_event *event) +{ + return (event->attr.config) & C2C_MASK_EVENT; +} + +static inline u32 get_filter_mask(struct perf_event *event) +{ + u32 filter; + struct nv_c2c_pmu *c2c_pmu = to_c2c_pmu(event->pmu); + + filter = ((u32)event->attr.config1) & c2c_pmu->filter_default; + if (filter == 0) + filter = c2c_pmu->filter_default; + + return filter; +} + +/* PMU operations. */ + +static int nv_c2c_pmu_get_event_idx(struct nv_c2c_pmu_hw_events *hw_events, + struct perf_event *event) +{ + u32 idx; + + idx = find_first_zero_bit(hw_events->used_ctrs, C2C_MAX_ACTIVE_EVENTS); + if (idx >= C2C_MAX_ACTIVE_EVENTS) + return -EAGAIN; + + set_bit(idx, hw_events->used_ctrs); + + return idx; +} + +static bool +nv_c2c_pmu_validate_event(struct pmu *pmu, + struct nv_c2c_pmu_hw_events *hw_events, + struct perf_event *event) +{ + if (is_software_event(event)) + return true; + + /* Reject groups spanning multiple HW PMUs. */ + if (event->pmu != pmu) + return false; + + return nv_c2c_pmu_get_event_idx(hw_events, event) >= 0; +} + +/* + * Make sure the group of events can be scheduled at once + * on the PMU. + */ +static bool nv_c2c_pmu_validate_group(struct perf_event *event) +{ + struct perf_event *sibling, *leader = event->group_leader; + struct nv_c2c_pmu_hw_events fake_hw_events; + + if (event->group_leader == event) + return true; + + memset(&fake_hw_events, 0, sizeof(fake_hw_events)); + + if (!nv_c2c_pmu_validate_event(event->pmu, &fake_hw_events, leader)) + return false; + + for_each_sibling_event(sibling, leader) { + if (!nv_c2c_pmu_validate_event(event->pmu, &fake_hw_events, + sibling)) + return false; + } + + return nv_c2c_pmu_validate_event(event->pmu, &fake_hw_events, event); +} + +static int nv_c2c_pmu_event_init(struct perf_event *event) +{ + struct nv_c2c_pmu *c2c_pmu = to_c2c_pmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + u32 event_type = get_event_type(event); + + if (event->attr.type != event->pmu->type || + event_type >= C2C_NUM_EVENTS) + return -ENOENT; + + /* + * Following other "uncore" PMUs, we do not support sampling mode or + * attach to a task (per-process mode). + */ + if (is_sampling_event(event)) { + dev_dbg(c2c_pmu->pmu.dev, "Can't support sampling events\n"); + return -EOPNOTSUPP; + } + + if (event->cpu < 0 || event->attach_state & PERF_ATTACH_TASK) { + dev_dbg(c2c_pmu->pmu.dev, "Can't support per-task counters\n"); + return -EINVAL; + } + + /* + * Make sure the CPU assignment is on one of the CPUs associated with + * this PMU. + */ + if (!cpumask_test_cpu(event->cpu, &c2c_pmu->associated_cpus)) { + dev_dbg(c2c_pmu->pmu.dev, + "Requested cpu is not associated with the PMU\n"); + return -EINVAL; + } + + /* Enforce the current active CPU to handle the events in this PMU. */ + event->cpu = cpumask_first(&c2c_pmu->active_cpu); + if (event->cpu >= nr_cpu_ids) + return -EINVAL; + + if (!nv_c2c_pmu_validate_group(event)) + return -EINVAL; + + hwc->idx = -1; + hwc->config = event_type; + + return 0; +} + +/* + * Read 64-bit register as a pair of 32-bit registers using hi-lo-hi sequence. + */ +static u64 read_reg64_hilohi(const void __iomem *addr, u32 max_poll_count) +{ + u32 val_lo, val_hi; + u64 val; + + /* Use high-low-high sequence to avoid tearing */ + do { + if (max_poll_count-- == 0) { + pr_err("NV C2C PMU: timeout hi-low-high sequence\n"); + return 0; + } + + val_hi = readl(addr + 4); + val_lo = readl(addr); + } while (val_hi != readl(addr + 4)); + + val = (((u64)val_hi << 32) | val_lo); + + return val; +} + +static void nv_c2c_pmu_check_status(struct nv_c2c_pmu *c2c_pmu, u32 instance) +{ + u32 in_status, out_status; + + in_status = readl(c2c_pmu->base[instance] + C2C_IN_STATUS); + out_status = readl(c2c_pmu->base[instance] + C2C_OUT_STATUS); + + if (in_status || out_status) + dev_warn(c2c_pmu->dev, + "C2C PMU overflow in: 0x%x, out: 0x%x\n", + in_status, out_status); +} + +static u32 nv_c2c_ctr_offset[C2C_NUM_EVENTS] = { + [C2C_EVENT_CYCLES] = C2C_CYCLE_CNTR, + [C2C_EVENT_IN_RD_CUM_OUTS] = C2C_IN_RD_CUM_OUTS_CNTR, + [C2C_EVENT_IN_RD_REQ] = C2C_IN_RD_REQ_CNTR, + [C2C_EVENT_IN_WR_CUM_OUTS] = C2C_IN_WR_CUM_OUTS_CNTR, + [C2C_EVENT_IN_WR_REQ] = C2C_IN_WR_REQ_CNTR, + [C2C_EVENT_OUT_RD_CUM_OUTS] = C2C_OUT_RD_CUM_OUTS_CNTR, + [C2C_EVENT_OUT_RD_REQ] = C2C_OUT_RD_REQ_CNTR, + [C2C_EVENT_OUT_WR_CUM_OUTS] = C2C_OUT_WR_CUM_OUTS_CNTR, + [C2C_EVENT_OUT_WR_REQ] = C2C_OUT_WR_REQ_CNTR, +}; + +static u64 nv_c2c_pmu_read_counter(struct perf_event *event) +{ + u32 ctr_id, ctr_offset, filter_mask, filter_idx, inst_idx; + unsigned long *inst_mask; + DECLARE_BITMAP(filter_bitmap, C2C_NR_PEER_MAX); + struct nv_c2c_pmu *c2c_pmu = to_c2c_pmu(event->pmu); + u64 val = 0; + + filter_mask = get_filter_mask(event); + bitmap_from_arr32(filter_bitmap, &filter_mask, c2c_pmu->nr_peer); + + ctr_id = event->hw.config; + ctr_offset = nv_c2c_ctr_offset[ctr_id]; + + for_each_set_bit(filter_idx, filter_bitmap, c2c_pmu->nr_peer) { + inst_mask = c2c_pmu->peer_insts[filter_idx]; + for_each_set_bit(inst_idx, inst_mask, c2c_pmu->data->nr_inst) { + nv_c2c_pmu_check_status(c2c_pmu, inst_idx); + + /* + * Each instance share same clock and the driver always + * enables all instances. So we can use the counts from + * one instance for cycle counter. + */ + if (ctr_id == C2C_EVENT_CYCLES) + return read_reg64_hilohi( + c2c_pmu->base[inst_idx] + ctr_offset, + HILOHI_MAX_POLL); + + /* + * For other events, sum up the counts from all instances. + */ + val += read_reg64_hilohi( + c2c_pmu->base[inst_idx] + ctr_offset, + HILOHI_MAX_POLL); + } + } + + return val; +} + +static void nv_c2c_pmu_event_update(struct perf_event *event) +{ + struct hw_perf_event *hwc = &event->hw; + u64 prev, now; + + do { + prev = local64_read(&hwc->prev_count); + now = nv_c2c_pmu_read_counter(event); + } while (local64_cmpxchg(&hwc->prev_count, prev, now) != prev); + + local64_add(now - prev, &event->count); +} + +static void nv_c2c_pmu_start(struct perf_event *event, int pmu_flags) +{ + event->hw.state = 0; +} + +static void nv_c2c_pmu_stop(struct perf_event *event, int pmu_flags) +{ + event->hw.state |= PERF_HES_STOPPED; +} + +static int nv_c2c_pmu_add(struct perf_event *event, int flags) +{ + struct nv_c2c_pmu *c2c_pmu = to_c2c_pmu(event->pmu); + struct nv_c2c_pmu_hw_events *hw_events = &c2c_pmu->hw_events; + struct hw_perf_event *hwc = &event->hw; + int idx; + + if (WARN_ON_ONCE(!cpumask_test_cpu(smp_processor_id(), + &c2c_pmu->associated_cpus))) + return -ENOENT; + + idx = nv_c2c_pmu_get_event_idx(hw_events, event); + if (idx < 0) + return idx; + + hw_events->events[idx] = event; + hwc->idx = idx; + hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE; + + if (flags & PERF_EF_START) + nv_c2c_pmu_start(event, PERF_EF_RELOAD); + + /* Propagate changes to the userspace mapping. */ + perf_event_update_userpage(event); + + return 0; +} + +static void nv_c2c_pmu_del(struct perf_event *event, int flags) +{ + struct nv_c2c_pmu *c2c_pmu = to_c2c_pmu(event->pmu); + struct nv_c2c_pmu_hw_events *hw_events = &c2c_pmu->hw_events; + struct hw_perf_event *hwc = &event->hw; + int idx = hwc->idx; + + nv_c2c_pmu_stop(event, PERF_EF_UPDATE); + + hw_events->events[idx] = NULL; + + clear_bit(idx, hw_events->used_ctrs); + + perf_event_update_userpage(event); +} + +static void nv_c2c_pmu_read(struct perf_event *event) +{ + nv_c2c_pmu_event_update(event); +} + +static void nv_c2c_pmu_enable(struct pmu *pmu) +{ + void __iomem *bcast; + struct nv_c2c_pmu *c2c_pmu = to_c2c_pmu(pmu); + + /* Check if any filter is enabled. */ + if (bitmap_empty(c2c_pmu->hw_events.used_ctrs, C2C_MAX_ACTIVE_EVENTS)) + return; + + /* Enable all the counters. */ + bcast = c2c_pmu->base_broadcast; + writel(0x1UL, bcast + C2C_CTRL); +} + +static void nv_c2c_pmu_disable(struct pmu *pmu) +{ + unsigned int idx; + void __iomem *bcast; + struct perf_event *event; + struct nv_c2c_pmu *c2c_pmu = to_c2c_pmu(pmu); + + /* Disable all the counters. */ + bcast = c2c_pmu->base_broadcast; + writel(0x0UL, bcast + C2C_CTRL); + + /* + * The counters will start from 0 again on restart. + * Update the events immediately to avoid losing the counts. + */ + for_each_set_bit(idx, c2c_pmu->hw_events.used_ctrs, + C2C_MAX_ACTIVE_EVENTS) { + event = c2c_pmu->hw_events.events[idx]; + + if (!event) + continue; + + nv_c2c_pmu_event_update(event); + + local64_set(&event->hw.prev_count, 0ULL); + } +} + +/* PMU identifier attribute. */ + +static ssize_t nv_c2c_pmu_identifier_show(struct device *dev, + struct device_attribute *attr, + char *page) +{ + struct nv_c2c_pmu *c2c_pmu = to_c2c_pmu(dev_get_drvdata(dev)); + + return sysfs_emit(page, "%s\n", c2c_pmu->identifier); +} + +static struct device_attribute nv_c2c_pmu_identifier_attr = + __ATTR(identifier, 0444, nv_c2c_pmu_identifier_show, NULL); + +static struct attribute *nv_c2c_pmu_identifier_attrs[] = { + &nv_c2c_pmu_identifier_attr.attr, + NULL, +}; + +static struct attribute_group nv_c2c_pmu_identifier_attr_group = { + .attrs = nv_c2c_pmu_identifier_attrs, +}; + +/* Peer attribute. */ + +static ssize_t nv_c2c_pmu_peer_show(struct device *dev, + struct device_attribute *attr, + char *page) +{ + const char *peer_type[C2C_PEER_TYPE_COUNT] = { + [C2C_PEER_TYPE_CPU] = "cpu", + [C2C_PEER_TYPE_GPU] = "gpu", + [C2C_PEER_TYPE_CXLMEM] = "cxlmem", + }; + + struct nv_c2c_pmu *c2c_pmu = to_c2c_pmu(dev_get_drvdata(dev)); + return sysfs_emit(page, "nr_%s=%u\n", peer_type[c2c_pmu->peer_type], + c2c_pmu->nr_peer); +} + +static struct device_attribute nv_c2c_pmu_peer_attr = + __ATTR(peer, 0444, nv_c2c_pmu_peer_show, NULL); + +static struct attribute *nv_c2c_pmu_peer_attrs[] = { + &nv_c2c_pmu_peer_attr.attr, + NULL, +}; + +static struct attribute_group nv_c2c_pmu_peer_attr_group = { + .attrs = nv_c2c_pmu_peer_attrs, +}; + +/* Format attributes. */ + +#define NV_C2C_PMU_EXT_ATTR(_name, _func, _config) \ + (&((struct dev_ext_attribute[]){ \ + { \ + .attr = __ATTR(_name, 0444, _func, NULL), \ + .var = (void *)_config \ + } \ + })[0].attr.attr) + +#define NV_C2C_PMU_FORMAT_ATTR(_name, _config) \ + NV_C2C_PMU_EXT_ATTR(_name, device_show_string, _config) + +#define NV_C2C_PMU_FORMAT_EVENT_ATTR \ + NV_C2C_PMU_FORMAT_ATTR(event, "config:0-3") + +static struct attribute *nv_c2c_pmu_gpu_formats[] = { + NV_C2C_PMU_FORMAT_EVENT_ATTR, + NV_C2C_PMU_FORMAT_ATTR(gpu_mask, "config1:0-1"), + NULL, +}; + +static const struct attribute_group nv_c2c_pmu_gpu_format_group = { + .name = "format", + .attrs = nv_c2c_pmu_gpu_formats, +}; + +static struct attribute *nv_c2c_pmu_formats[] = { + NV_C2C_PMU_FORMAT_EVENT_ATTR, + NULL, +}; + +static const struct attribute_group nv_c2c_pmu_format_group = { + .name = "format", + .attrs = nv_c2c_pmu_formats, +}; + +/* Event attributes. */ + +static ssize_t nv_c2c_pmu_sysfs_event_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct perf_pmu_events_attr *pmu_attr; + + pmu_attr = container_of(attr, typeof(*pmu_attr), attr); + return sysfs_emit(buf, "event=0x%llx\n", pmu_attr->id); +} + +#define NV_C2C_PMU_EVENT_ATTR(_name, _config) \ + PMU_EVENT_ATTR_ID(_name, nv_c2c_pmu_sysfs_event_show, _config) + +static struct attribute *nv_c2c_pmu_gpu_events[] = { + NV_C2C_PMU_EVENT_ATTR(cycles, C2C_EVENT_CYCLES), + NV_C2C_PMU_EVENT_ATTR(in_rd_cum_outs, C2C_EVENT_IN_RD_CUM_OUTS), + NV_C2C_PMU_EVENT_ATTR(in_rd_req, C2C_EVENT_IN_RD_REQ), + NV_C2C_PMU_EVENT_ATTR(in_wr_cum_outs, C2C_EVENT_IN_WR_CUM_OUTS), + NV_C2C_PMU_EVENT_ATTR(in_wr_req, C2C_EVENT_IN_WR_REQ), + NV_C2C_PMU_EVENT_ATTR(out_rd_cum_outs, C2C_EVENT_OUT_RD_CUM_OUTS), + NV_C2C_PMU_EVENT_ATTR(out_rd_req, C2C_EVENT_OUT_RD_REQ), + NV_C2C_PMU_EVENT_ATTR(out_wr_cum_outs, C2C_EVENT_OUT_WR_CUM_OUTS), + NV_C2C_PMU_EVENT_ATTR(out_wr_req, C2C_EVENT_OUT_WR_REQ), + NULL +}; + +static const struct attribute_group nv_c2c_pmu_gpu_events_group = { + .name = "events", + .attrs = nv_c2c_pmu_gpu_events, +}; + +static struct attribute *nv_c2c_pmu_cpu_events[] = { + NV_C2C_PMU_EVENT_ATTR(cycles, C2C_EVENT_CYCLES), + NV_C2C_PMU_EVENT_ATTR(in_rd_cum_outs, C2C_EVENT_IN_RD_CUM_OUTS), + NV_C2C_PMU_EVENT_ATTR(in_rd_req, C2C_EVENT_IN_RD_REQ), + NV_C2C_PMU_EVENT_ATTR(out_rd_cum_outs, C2C_EVENT_OUT_RD_CUM_OUTS), + NV_C2C_PMU_EVENT_ATTR(out_rd_req, C2C_EVENT_OUT_RD_REQ), + NULL +}; + +static const struct attribute_group nv_c2c_pmu_cpu_events_group = { + .name = "events", + .attrs = nv_c2c_pmu_cpu_events, +}; + +static struct attribute *nv_c2c_pmu_cxlmem_events[] = { + NV_C2C_PMU_EVENT_ATTR(cycles, C2C_EVENT_CYCLES), + NV_C2C_PMU_EVENT_ATTR(in_rd_cum_outs, C2C_EVENT_IN_RD_CUM_OUTS), + NV_C2C_PMU_EVENT_ATTR(in_rd_req, C2C_EVENT_IN_RD_REQ), + NULL +}; + +static const struct attribute_group nv_c2c_pmu_cxlmem_events_group = { + .name = "events", + .attrs = nv_c2c_pmu_cxlmem_events, +}; + +/* Cpumask attributes. */ + +static ssize_t nv_c2c_pmu_cpumask_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct pmu *pmu = dev_get_drvdata(dev); + struct nv_c2c_pmu *c2c_pmu = to_c2c_pmu(pmu); + struct dev_ext_attribute *eattr = + container_of(attr, struct dev_ext_attribute, attr); + unsigned long mask_id = (unsigned long)eattr->var; + const cpumask_t *cpumask; + + switch (mask_id) { + case C2C_ACTIVE_CPU_MASK: + cpumask = &c2c_pmu->active_cpu; + break; + case C2C_ASSOCIATED_CPU_MASK: + cpumask = &c2c_pmu->associated_cpus; + break; + default: + return 0; + } + return cpumap_print_to_pagebuf(true, buf, cpumask); +} + +#define NV_C2C_PMU_CPUMASK_ATTR(_name, _config) \ + NV_C2C_PMU_EXT_ATTR(_name, nv_c2c_pmu_cpumask_show, \ + (unsigned long)_config) + +static struct attribute *nv_c2c_pmu_cpumask_attrs[] = { + NV_C2C_PMU_CPUMASK_ATTR(cpumask, C2C_ACTIVE_CPU_MASK), + NV_C2C_PMU_CPUMASK_ATTR(associated_cpus, C2C_ASSOCIATED_CPU_MASK), + NULL, +}; + +static const struct attribute_group nv_c2c_pmu_cpumask_attr_group = { + .attrs = nv_c2c_pmu_cpumask_attrs, +}; + +/* Attribute groups for C2C PMU connecting SoC and GPU */ +static const struct attribute_group *nv_c2c_pmu_gpu_attr_groups[] = { + &nv_c2c_pmu_gpu_format_group, + &nv_c2c_pmu_gpu_events_group, + &nv_c2c_pmu_cpumask_attr_group, + &nv_c2c_pmu_identifier_attr_group, + &nv_c2c_pmu_peer_attr_group, + NULL +}; + +/* Attribute groups for C2C PMU connecting multiple SoCs */ +static const struct attribute_group *nv_c2c_pmu_cpu_attr_groups[] = { + &nv_c2c_pmu_format_group, + &nv_c2c_pmu_cpu_events_group, + &nv_c2c_pmu_cpumask_attr_group, + &nv_c2c_pmu_identifier_attr_group, + &nv_c2c_pmu_peer_attr_group, + NULL +}; + +/* Attribute groups for C2C PMU connecting SoC and CXLMEM */ +static const struct attribute_group *nv_c2c_pmu_cxlmem_attr_groups[] = { + &nv_c2c_pmu_format_group, + &nv_c2c_pmu_cxlmem_events_group, + &nv_c2c_pmu_cpumask_attr_group, + &nv_c2c_pmu_identifier_attr_group, + &nv_c2c_pmu_peer_attr_group, + NULL +}; + +static int nv_c2c_pmu_online_cpu(unsigned int cpu, struct hlist_node *node) +{ + struct nv_c2c_pmu *c2c_pmu = + hlist_entry_safe(node, struct nv_c2c_pmu, cpuhp_node); + + if (!cpumask_test_cpu(cpu, &c2c_pmu->associated_cpus)) + return 0; + + /* If the PMU is already managed, there is nothing to do */ + if (!cpumask_empty(&c2c_pmu->active_cpu)) + return 0; + + /* Use this CPU for event counting */ + cpumask_set_cpu(cpu, &c2c_pmu->active_cpu); + + return 0; +} + +static int nv_c2c_pmu_cpu_teardown(unsigned int cpu, struct hlist_node *node) +{ + unsigned int dst; + + struct nv_c2c_pmu *c2c_pmu = + hlist_entry_safe(node, struct nv_c2c_pmu, cpuhp_node); + + /* Nothing to do if this CPU doesn't own the PMU */ + if (!cpumask_test_and_clear_cpu(cpu, &c2c_pmu->active_cpu)) + return 0; + + /* Choose a new CPU to migrate ownership of the PMU to */ + dst = cpumask_any_and_but(&c2c_pmu->associated_cpus, + cpu_online_mask, cpu); + if (dst >= nr_cpu_ids) + return 0; + + /* Use this CPU for event counting */ + perf_pmu_migrate_context(&c2c_pmu->pmu, cpu, dst); + cpumask_set_cpu(dst, &c2c_pmu->active_cpu); + + return 0; +} + +static int nv_c2c_pmu_get_cpus(struct nv_c2c_pmu *c2c_pmu) +{ + int socket = c2c_pmu->socket, cpu; + + for_each_possible_cpu(cpu) { + if (cpu_to_node(cpu) == socket) + cpumask_set_cpu(cpu, &c2c_pmu->associated_cpus); + } + + if (cpumask_empty(&c2c_pmu->associated_cpus)) { + dev_dbg(c2c_pmu->dev, + "No cpu associated with C2C PMU socket-%u\n", socket); + return -ENODEV; + } + + return 0; +} + +static int nv_c2c_pmu_init_socket(struct nv_c2c_pmu *c2c_pmu) +{ + const char *uid_str; + int ret, socket; + + uid_str = acpi_device_uid(c2c_pmu->acpi_dev); + if (!uid_str) { + dev_err(c2c_pmu->dev, "No ACPI device UID\n"); + return -ENODEV; + } + + ret = kstrtou32(uid_str, 0, &socket); + if (ret) { + dev_err(c2c_pmu->dev, "Failed to parse ACPI device UID\n"); + return ret; + } + + c2c_pmu->socket = socket; + return 0; +} + +static int nv_c2c_pmu_init_id(struct nv_c2c_pmu *c2c_pmu) +{ + char *name; + + name = devm_kasprintf(c2c_pmu->dev, GFP_KERNEL, c2c_pmu->data->name_fmt, + c2c_pmu->socket); + if (!name) + return -ENOMEM; + + c2c_pmu->name = name; + + c2c_pmu->identifier = acpi_device_hid(c2c_pmu->acpi_dev); + + return 0; +} + +static int nv_c2c_pmu_init_filter(struct nv_c2c_pmu *c2c_pmu) +{ + u32 cpu_en = 0; + struct device *dev = c2c_pmu->dev; + const struct nv_c2c_pmu_data *data = c2c_pmu->data; + + if (data->c2c_type == C2C_TYPE_NVDLINK) { + c2c_pmu->peer_type = C2C_PEER_TYPE_CXLMEM; + + c2c_pmu->peer_insts[0][0] = (1UL << data->nr_inst) - 1; + + c2c_pmu->nr_peer = C2C_NR_PEER_CXLMEM; + c2c_pmu->filter_default = (1 << c2c_pmu->nr_peer) - 1; + + c2c_pmu->attr_groups = nv_c2c_pmu_cxlmem_attr_groups; + + return 0; + } + + if (device_property_read_u32(dev, "cpu_en_mask", &cpu_en)) + dev_dbg(dev, "no cpu_en_mask property\n"); + + if (cpu_en) { + c2c_pmu->peer_type = C2C_PEER_TYPE_CPU; + + /* Fill peer_insts bitmap with instances connected to peer CPU. */ + bitmap_from_arr32(c2c_pmu->peer_insts[0], &cpu_en, data->nr_inst); + + c2c_pmu->nr_peer = 1; + c2c_pmu->attr_groups = nv_c2c_pmu_cpu_attr_groups; + } else { + u32 i; + const char *props[C2C_NR_PEER_MAX] = { + "gpu0_en_mask", "gpu1_en_mask" + }; + + for (i = 0; i < C2C_NR_PEER_MAX; i++) { + u32 gpu_en = 0; + + if (device_property_read_u32(dev, props[i], &gpu_en)) + dev_dbg(dev, "no %s property\n", props[i]); + + if (gpu_en) { + /* Fill peer_insts bitmap with instances connected to peer GPU. */ + bitmap_from_arr32(c2c_pmu->peer_insts[i], &gpu_en, + data->nr_inst); + + c2c_pmu->nr_peer++; + } + } + + if (c2c_pmu->nr_peer == 0) { + dev_err(dev, "No GPU is enabled\n"); + return -EINVAL; + } + + c2c_pmu->peer_type = C2C_PEER_TYPE_GPU; + c2c_pmu->attr_groups = nv_c2c_pmu_gpu_attr_groups; + } + + c2c_pmu->filter_default = (1 << c2c_pmu->nr_peer) - 1; + + return 0; +} + +static void *nv_c2c_pmu_init_pmu(struct platform_device *pdev) +{ + int ret; + struct nv_c2c_pmu *c2c_pmu; + struct acpi_device *acpi_dev; + struct device *dev = &pdev->dev; + + acpi_dev = ACPI_COMPANION(dev); + if (!acpi_dev) + return ERR_PTR(-ENODEV); + + c2c_pmu = devm_kzalloc(dev, sizeof(*c2c_pmu), GFP_KERNEL); + if (!c2c_pmu) + return ERR_PTR(-ENOMEM); + + c2c_pmu->dev = dev; + c2c_pmu->acpi_dev = acpi_dev; + c2c_pmu->data = (const struct nv_c2c_pmu_data *)device_get_match_data(dev); + if (!c2c_pmu->data) + return ERR_PTR(-EINVAL); + + platform_set_drvdata(pdev, c2c_pmu); + + ret = nv_c2c_pmu_init_socket(c2c_pmu); + if (ret) + return ERR_PTR(ret); + + ret = nv_c2c_pmu_init_id(c2c_pmu); + if (ret) + return ERR_PTR(ret); + + ret = nv_c2c_pmu_init_filter(c2c_pmu); + if (ret) + return ERR_PTR(ret); + + return c2c_pmu; +} + +static int nv_c2c_pmu_init_mmio(struct nv_c2c_pmu *c2c_pmu) +{ + int i; + struct device *dev = c2c_pmu->dev; + struct platform_device *pdev = to_platform_device(dev); + const struct nv_c2c_pmu_data *data = c2c_pmu->data; + + /* Map the address of all the instances. */ + for (i = 0; i < data->nr_inst; i++) { + c2c_pmu->base[i] = devm_platform_ioremap_resource(pdev, i); + if (IS_ERR(c2c_pmu->base[i])) { + dev_err(dev, "Failed map address for instance %d\n", i); + return PTR_ERR(c2c_pmu->base[i]); + } + } + + /* Map broadcast address. */ + c2c_pmu->base_broadcast = devm_platform_ioremap_resource(pdev, + data->nr_inst); + if (IS_ERR(c2c_pmu->base_broadcast)) { + dev_err(dev, "Failed map broadcast address\n"); + return PTR_ERR(c2c_pmu->base_broadcast); + } + + return 0; +} + +static int nv_c2c_pmu_register_pmu(struct nv_c2c_pmu *c2c_pmu) +{ + int ret; + + ret = cpuhp_state_add_instance(nv_c2c_pmu_cpuhp_state, + &c2c_pmu->cpuhp_node); + if (ret) { + dev_err(c2c_pmu->dev, "Error %d registering hotplug\n", ret); + return ret; + } + + c2c_pmu->pmu = (struct pmu) { + .parent = c2c_pmu->dev, + .task_ctx_nr = perf_invalid_context, + .pmu_enable = nv_c2c_pmu_enable, + .pmu_disable = nv_c2c_pmu_disable, + .event_init = nv_c2c_pmu_event_init, + .add = nv_c2c_pmu_add, + .del = nv_c2c_pmu_del, + .start = nv_c2c_pmu_start, + .stop = nv_c2c_pmu_stop, + .read = nv_c2c_pmu_read, + .attr_groups = c2c_pmu->attr_groups, + .capabilities = PERF_PMU_CAP_NO_EXCLUDE | + PERF_PMU_CAP_NO_INTERRUPT, + }; + + ret = perf_pmu_register(&c2c_pmu->pmu, c2c_pmu->name, -1); + if (ret) { + dev_err(c2c_pmu->dev, "Failed to register C2C PMU: %d\n", ret); + cpuhp_state_remove_instance(nv_c2c_pmu_cpuhp_state, + &c2c_pmu->cpuhp_node); + return ret; + } + + return 0; +} + +static int nv_c2c_pmu_probe(struct platform_device *pdev) +{ + int ret; + struct nv_c2c_pmu *c2c_pmu; + + c2c_pmu = nv_c2c_pmu_init_pmu(pdev); + if (IS_ERR(c2c_pmu)) + return PTR_ERR(c2c_pmu); + + ret = nv_c2c_pmu_init_mmio(c2c_pmu); + if (ret) + return ret; + + ret = nv_c2c_pmu_get_cpus(c2c_pmu); + if (ret) + return ret; + + ret = nv_c2c_pmu_register_pmu(c2c_pmu); + if (ret) + return ret; + + dev_dbg(c2c_pmu->dev, "Registered %s PMU\n", c2c_pmu->name); + + return 0; +} + +static void nv_c2c_pmu_device_remove(struct platform_device *pdev) +{ + struct nv_c2c_pmu *c2c_pmu = platform_get_drvdata(pdev); + + perf_pmu_unregister(&c2c_pmu->pmu); + cpuhp_state_remove_instance(nv_c2c_pmu_cpuhp_state, &c2c_pmu->cpuhp_node); +} + +static const struct acpi_device_id nv_c2c_pmu_acpi_match[] = { + { "NVDA2023", (kernel_ulong_t)&nv_c2c_pmu_data[C2C_TYPE_NVLINK] }, + { "NVDA2022", (kernel_ulong_t)&nv_c2c_pmu_data[C2C_TYPE_NVCLINK] }, + { "NVDA2020", (kernel_ulong_t)&nv_c2c_pmu_data[C2C_TYPE_NVDLINK] }, + { } +}; +MODULE_DEVICE_TABLE(acpi, nv_c2c_pmu_acpi_match); + +static struct platform_driver nv_c2c_pmu_driver = { + .driver = { + .name = "nvidia-t410-c2c-pmu", + .acpi_match_table = nv_c2c_pmu_acpi_match, + .suppress_bind_attrs = true, + }, + .probe = nv_c2c_pmu_probe, + .remove = nv_c2c_pmu_device_remove, +}; + +static int __init nv_c2c_pmu_init(void) +{ + int ret; + + ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, + "perf/nvidia/c2c:online", + nv_c2c_pmu_online_cpu, + nv_c2c_pmu_cpu_teardown); + if (ret < 0) + return ret; + + nv_c2c_pmu_cpuhp_state = ret; + return platform_driver_register(&nv_c2c_pmu_driver); +} + +static void __exit nv_c2c_pmu_exit(void) +{ + platform_driver_unregister(&nv_c2c_pmu_driver); + cpuhp_remove_multi_state(nv_c2c_pmu_cpuhp_state); +} + +module_init(nv_c2c_pmu_init); +module_exit(nv_c2c_pmu_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("NVIDIA Tegra410 C2C PMU driver"); +MODULE_AUTHOR("Besar Wicaksono ");