From 741e5c45179db066ddf5bed0be6f36e4d0d4010e Mon Sep 17 00:00:00 2001 From: Thomas Fleury Date: Thu, 27 Apr 2017 11:28:27 -0700 Subject: gpu: nvgpu: hal for timestamps correlation In order to perform timestamps correlation for FECS traces, we need to collect GPU / GPU timestamps samples. In virtualization case, it is possible for a guest to get GPU timestamps by using read_ptimer. However, if the CPU timestamp is read on guest side, and the GPU timestamp is read on vm-server side, then it introduces some latency that will create an artificial offset for GPU timestamps (~2 us in average). For better CPU / GPU timestamps correlation, Added a command to collect all timestamps on vm-server side. Bug 1900475 Change-Id: Idfdc6ae4c16c501dc5e00053a5b75932c55148d6 Signed-off-by: Thomas Fleury Reviewed-on: http://git-master/r/1472447 (cherry picked from commit 56f56b5cd9d2e75cf7d2613b5e115bfebdbee0ce) Reviewed-on: http://git-master/r/1489183 Reviewed-by: mobile promotions Tested-by: mobile promotions --- drivers/gpu/nvgpu/gk20a/bus_gk20a.c | 61 +++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) (limited to 'drivers/gpu/nvgpu/gk20a/bus_gk20a.c') diff --git a/drivers/gpu/nvgpu/gk20a/bus_gk20a.c b/drivers/gpu/nvgpu/gk20a/bus_gk20a.c index 52ef08e4..7f0ca013 100644 --- a/drivers/gpu/nvgpu/gk20a/bus_gk20a.c +++ b/drivers/gpu/nvgpu/gk20a/bus_gk20a.c @@ -128,6 +128,66 @@ int gk20a_read_ptimer(struct gk20a *g, u64 *value) return -EBUSY; } +static inline u64 get_cpu_timestamp_tsc(void) +{ + return ((u64) get_cycles()); +} + +static inline u64 get_cpu_timestamp_jiffies(void) +{ + return (get_jiffies_64() - INITIAL_JIFFIES); +} + +static inline u64 get_cpu_timestamp_timeofday(void) +{ + struct timeval tv; + + do_gettimeofday(&tv); + return timeval_to_jiffies(&tv); +} + +int gk20a_get_timestamps_zipper(struct gk20a *g, + u32 source_id, u32 count, + struct nvgpu_cpu_time_correlation_sample *samples) +{ + int err = 0; + unsigned int i = 0; + u64 (*get_cpu_timestamp)(void) = NULL; + + switch (source_id) { + case NVGPU_GPU_GET_CPU_TIME_CORRELATION_INFO_SRC_ID_TSC: + get_cpu_timestamp = get_cpu_timestamp_tsc; + break; + case NVGPU_GPU_GET_CPU_TIME_CORRELATION_INFO_SRC_ID_JIFFIES: + get_cpu_timestamp = get_cpu_timestamp_jiffies; + break; + case NVGPU_GPU_GET_CPU_TIME_CORRELATION_INFO_SRC_ID_TIMEOFDAY: + get_cpu_timestamp = get_cpu_timestamp_timeofday; + break; + default: + nvgpu_err(g, "invalid cpu clock source id\n"); + return -EINVAL; + } + + if (gk20a_busy(g)) { + nvgpu_err(g, "GPU not powered on\n"); + err = -EINVAL; + goto end; + } + + for (i = 0; i < count; i++) { + err = g->ops.bus.read_ptimer(g, &samples[i].gpu_timestamp); + if (err) + return err; + + samples[i].cpu_timestamp = get_cpu_timestamp(); + } + +end: + gk20a_idle(g); + return err; +} + static int gk20a_bus_bar1_bind(struct gk20a *g, struct nvgpu_mem *bar1_inst) { u64 iova = gk20a_mm_inst_block_addr(g, bar1_inst); @@ -150,5 +210,6 @@ void gk20a_init_bus(struct gpu_ops *gops) gops->bus.init_hw = gk20a_bus_init_hw; gops->bus.isr = gk20a_bus_isr; gops->bus.read_ptimer = gk20a_read_ptimer; + gops->bus.get_timestamps_zipper = gk20a_get_timestamps_zipper; gops->bus.bar1_bind = gk20a_bus_bar1_bind; } -- cgit v1.2.2