drm/i915/guc: Add GuC <-> kernel time stamp translation information

It is useful to be able to match GuC events to kernel events when
looking at the GuC log. That requires being able to convert GuC
timestamps to kernel time. So, when dumping error captures and/or GuC
logs, include a stamp in both time zones plus the clock frequency.
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220728022028.2190627-4-John.C.Harrison@Intel.com

drivers/gpu/drm/i915/gt/intel_gt_regs.h

@@ -1013,6 +1013,8 @@
 #define   GEN11_LSN_UNSLCVC_GAFS_HALF_CL2_MAXALLOC	(1 << 9)
 #define   GEN11_LSN_UNSLCVC_GAFS_HALF_SF_MAXALLOC	(1 << 7)
 
+#define GUCPMTIMESTAMP				_MMIO(0xc3e8)
+
 #define __GEN9_RCS0_MOCS0			0xc800
 #define GEN9_GFX_MOCS(i)			_MMIO(__GEN9_RCS0_MOCS0 + (i) * 4)
 #define __GEN9_VCS0_MOCS0			0xc900

drivers/gpu/drm/i915/gt/uc/intel_guc.c

@@ -389,6 +389,25 @@ void intel_guc_write_params(struct intel_guc *guc)
 	intel_uncore_forcewake_put(uncore, FORCEWAKE_GT);
 }
 
+void intel_guc_dump_time_info(struct intel_guc *guc, struct drm_printer *p)
+{
+	struct intel_gt *gt = guc_to_gt(guc);
+	intel_wakeref_t wakeref;
+	u32 stamp = 0;
+	u64 ktime;
+
+	intel_device_info_print_runtime(RUNTIME_INFO(gt->i915), p);
+
+	with_intel_runtime_pm(&gt->i915->runtime_pm, wakeref)
+		stamp = intel_uncore_read(gt->uncore, GUCPMTIMESTAMP);
+	ktime = ktime_get_boottime_ns();
+
+	drm_printf(p, "Kernel timestamp: 0x%08llX [%llu]\n", ktime, ktime);
+	drm_printf(p, "GuC timestamp: 0x%08X [%u]\n", stamp, stamp);
+	drm_printf(p, "CS timestamp frequency: %u Hz, %u ns\n",
+		   gt->clock_frequency, gt->clock_period_ns);
+}
+
 int intel_guc_init(struct intel_guc *guc)
 {
 	struct intel_gt *gt = guc_to_gt(guc);

drivers/gpu/drm/i915/gt/uc/intel_guc.h

@@ -464,4 +464,6 @@ void intel_guc_load_status(struct intel_guc *guc, struct drm_printer *p);
 
 void intel_guc_write_barrier(struct intel_guc *guc);
 
+void intel_guc_dump_time_info(struct intel_guc *guc, struct drm_printer *p);
+
 #endif

drivers/gpu/drm/i915/gt/uc/intel_guc_log.c

@@ -764,6 +764,8 @@ int intel_guc_log_dump(struct intel_guc_log *log, struct drm_printer *p,
 	if (!obj)
 		return 0;
 
+	intel_guc_dump_time_info(guc, p);
+
 	map = i915_gem_object_pin_map_unlocked(obj, I915_MAP_WC);
 	if (IS_ERR(map)) {
 		DRM_DEBUG("Failed to pin object\n");

drivers/gpu/drm/i915/i915_gpu_error.c

@@ -678,6 +678,7 @@ static void err_print_uc(struct drm_i915_error_state_buf *m,
 
 	intel_uc_fw_dump(&error_uc->guc_fw, &p);
 	intel_uc_fw_dump(&error_uc->huc_fw, &p);
+	err_printf(m, "GuC timestamp: 0x%08x\n", error_uc->timestamp);
 	intel_gpu_error_print_vma(m, NULL, error_uc->guc_log);
 }
 
@@ -720,6 +721,8 @@ static void err_print_gt_global_nonguc(struct drm_i915_error_state_buf *m,
 	int i;
 
 	err_printf(m, "GT awake: %s\n", str_yes_no(gt->awake));
+	err_printf(m, "CS timestamp frequency: %u Hz, %d ns\n",
+		   gt->clock_frequency, gt->clock_period_ns);
 	err_printf(m, "EIR: 0x%08x\n", gt->eir);
 	err_printf(m, "PGTBL_ER: 0x%08x\n", gt->pgtbl_er);
 
@@ -1675,6 +1678,13 @@ gt_record_uc(struct intel_gt_coredump *gt,
 	 */
 	error_uc->guc_fw.path = kstrdup(uc->guc.fw.path, ALLOW_FAIL);
 	error_uc->huc_fw.path = kstrdup(uc->huc.fw.path, ALLOW_FAIL);
+
+	/*
+	 * Save the GuC log and include a timestamp reference for converting the
+	 * log times to system times (in conjunction with the error->boottime and
+	 * gt->clock_frequency fields saved elsewhere).
+	 */
+	error_uc->timestamp = intel_uncore_read(gt->_gt->uncore, GUCPMTIMESTAMP);
 	error_uc->guc_log = create_vma_coredump(gt->_gt, uc->guc.log.vma,
 						"GuC log buffer", compress);
 
@@ -1833,6 +1843,8 @@ static void gt_record_global_regs(struct intel_gt_coredump *gt)
 static void gt_record_info(struct intel_gt_coredump *gt)
 {
 	memcpy(&gt->info, &gt->_gt->info, sizeof(struct intel_gt_info));
+	gt->clock_frequency = gt->_gt->clock_frequency;
+	gt->clock_period_ns = gt->_gt->clock_period_ns;
 }
 
 /*

drivers/gpu/drm/i915/i915_gpu_error.h

@@ -150,6 +150,8 @@ struct intel_gt_coredump {
 	u32 gtt_cache;
 	u32 aux_err; /* gen12 */
 	u32 gam_done; /* gen12 */
+	u32 clock_frequency;
+	u32 clock_period_ns;
 
 	/* Display related */
 	u32 derrmr;
@@ -164,6 +166,7 @@ struct intel_gt_coredump {
 		struct intel_uc_fw guc_fw;
 		struct intel_uc_fw huc_fw;
 		struct i915_vma_coredump *guc_log;
+		u32 timestamp;
 		bool is_guc_capture;
 	} *uc;