drm/i915/guc: Extract GuC error capture lists on G2H notification.

- Upon the G2H Notify-Err-Capture event, parse through the
  GuC Log Buffer (error-capture-subregion) and generate one or
  more capture-nodes. A single node represents a single "engine-
  instance-capture-dump" and contains at least 3 register lists:
  global, engine-class and engine-instance. An internal link
  list is maintained to store one or more nodes.
- Because the link-list node generation happen before the call
  to i915_gpu_codedump, duplicate global and engine-class register
  lists for each engine-instance register dump if we find
  dependent-engine resets in a engine-capture-group.
- When i915_gpu_coredump calls into capture_engine, (in a
  subsequent patch) we detach the matching node (guc-id,
  LRCA, etc) from the link list above and attach it to
  i915_gpu_coredump's intel_engine_coredump structure when have
  matching LRCA/guc-id/engine-instance.

Additional notes to be aware of:
- GuC generates the error capture dump into the GuC log buffer but
  this buffer is one big log buffer with 3 independent subregions
  within it. Each subregion is populated with different content
  and used in different ways and timings but all regions operate
  behave as independent ring buffers. Each guc-log subregion
  (general-logs, crash-dump and error- capture) has it's own
  guc_log_buffer_state that contain independent read and write
  pointers.
Signed-off-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Reviewed-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220321164527.2500062-11-alan.previn.teres.alexis@intel.com

drivers/gpu/drm/i915/gt/uc/abi/guc_actions_abi.h

@@ -172,4 +172,11 @@ enum intel_guc_sleep_state_status {
 #define GUC_LOG_CONTROL_VERBOSITY_MASK	(0xF << GUC_LOG_CONTROL_VERBOSITY_SHIFT)
 #define GUC_LOG_CONTROL_DEFAULT_LOGGING	(1 << 8)
 
+enum intel_guc_state_capture_event_status {
+	INTEL_GUC_STATE_CAPTURE_EVENT_STATUS_SUCCESS = 0x0,
+	INTEL_GUC_STATE_CAPTURE_EVENT_STATUS_NOSPACE = 0x1,
+};
+
+#define INTEL_GUC_STATE_CAPTURE_EVENT_STATUS_MASK      0x000000FF
+
 #endif /* _ABI_GUC_ACTIONS_ABI_H */

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

@@ -12,6 +12,52 @@
 struct intel_guc;
 struct file;
 
+/**
+ * struct __guc_capture_bufstate
+ *
+ * Book-keeping structure used to track read and write pointers
+ * as we extract error capture data from the GuC-log-buffer's
+ * error-capture region as a stream of dwords.
+ */
+struct __guc_capture_bufstate {
+	u32 size;
+	void *data;
+	u32 rd;
+	u32 wr;
+};
+
+/**
+ * struct __guc_capture_parsed_output - extracted error capture node
+ *
+ * A single unit of extracted error-capture output data grouped together
+ * at an engine-instance level. We keep these nodes in a linked list.
+ * See outlist below.
+ */
+struct __guc_capture_parsed_output {
+	/*
+	 * A single set of 3 capture lists: a global-list
+	 * an engine-class-list and an engine-instance list.
+	 * outlist in __guc_capture_parsed_output will keep
+	 * a linked list of these nodes that will eventually
+	 * be detached from outlist and attached into to
+	 * i915_gpu_codedump in response to a context reset
+	 */
+	struct list_head link;
+	bool is_partial;
+	u32 eng_class;
+	u32 eng_inst;
+	u32 guc_id;
+	u32 lrca;
+	struct gcap_reg_list_info {
+		u32 vfid;
+		u32 num_regs;
+		struct guc_mmio_reg *regs;
+	} reginfo[GUC_CAPTURE_LIST_TYPE_MAX];
+#define GCAP_PARSED_REGLIST_INDEX_GLOBAL   BIT(GUC_CAPTURE_LIST_TYPE_GLOBAL)
+#define GCAP_PARSED_REGLIST_INDEX_ENGCLASS BIT(GUC_CAPTURE_LIST_TYPE_ENGINE_CLASS)
+#define GCAP_PARSED_REGLIST_INDEX_ENGINST  BIT(GUC_CAPTURE_LIST_TYPE_ENGINE_INSTANCE)
+};
+
 /**
  * struct guc_debug_capture_list_header / struct guc_debug_capture_list
  *
@@ -142,6 +188,16 @@ struct intel_guc_state_capture {
 						[GUC_CAPTURE_LIST_TYPE_MAX]
 						[GUC_MAX_ENGINE_CLASSES];
 	void *ads_null_cache;
+
+	/**
+	 * @outlist: allocated nodes with parsed engine-instance error capture data
+	 *
+	 * A linked list of parsed GuC error-capture output data before
+	 * reporting with formatting via i915_gpu_coredump. Each node in this linked list shall
+	 * contain a single engine-capture including global, engine-class and
+	 * engine-instance register dumps as per guc_capture_parsed_output_node
+	 */
+	struct list_head outlist;
 };
 
 #endif /* _INTEL_GUC_CAPTURE_FWIF_H */

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

@@ -11,6 +11,7 @@
 struct guc_gt_system_info;
 struct intel_guc;
 
+void intel_guc_capture_process(struct intel_guc *guc);
 int intel_guc_capture_output_min_size_est(struct intel_guc *guc);
 int intel_guc_capture_getlist(struct intel_guc *guc, u32 owner, u32 type, u32 classid,
 			      void **outptr);

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

@@ -158,9 +158,9 @@ static void *guc_get_write_buffer(struct intel_guc_log *log)
 	return relay_reserve(log->relay.channel, 0);
 }
 
-static bool guc_check_log_buf_overflow(struct intel_guc_log *log,
-				       enum guc_log_buffer_type type,
-				       unsigned int full_cnt)
+bool intel_guc_check_log_buf_overflow(struct intel_guc_log *log,
+				      enum guc_log_buffer_type type,
+				      unsigned int full_cnt)
 {
 	unsigned int prev_full_cnt = log->stats[type].sampled_overflow;
 	bool overflow = false;
@@ -183,7 +183,7 @@ static bool guc_check_log_buf_overflow(struct intel_guc_log *log,
 	return overflow;
 }
 
-static unsigned int guc_get_log_buffer_size(enum guc_log_buffer_type type)
+unsigned int intel_guc_get_log_buffer_size(enum guc_log_buffer_type type)
 {
 	switch (type) {
 	case GUC_DEBUG_LOG_BUFFER:
@@ -199,6 +199,20 @@ static unsigned int guc_get_log_buffer_size(enum guc_log_buffer_type type)
 	return 0;
 }
 
+size_t intel_guc_get_log_buffer_offset(enum guc_log_buffer_type type)
+{
+	enum guc_log_buffer_type i;
+	size_t offset = PAGE_SIZE;/* for the log_buffer_states */
+
+	for (i = GUC_DEBUG_LOG_BUFFER; i < GUC_MAX_LOG_BUFFER; ++i) {
+		if (i == type)
+			break;
+		offset += intel_guc_get_log_buffer_size(i);
+	}
+
+	return offset;
+}
+
 static void _guc_log_copy_debuglogs_for_relay(struct intel_guc_log *log)
 {
 	unsigned int buffer_size, read_offset, write_offset, bytes_to_copy, full_cnt;
@@ -244,14 +258,14 @@ static void _guc_log_copy_debuglogs_for_relay(struct intel_guc_log *log)
 		 */
 		memcpy(&log_buf_state_local, log_buf_state,
 		       sizeof(struct guc_log_buffer_state));
-		buffer_size = guc_get_log_buffer_size(type);
+		buffer_size = intel_guc_get_log_buffer_size(type);
 		read_offset = log_buf_state_local.read_ptr;
 		write_offset = log_buf_state_local.sampled_write_ptr;
 		full_cnt = log_buf_state_local.buffer_full_cnt;
 
 		/* Bookkeeping stuff */
 		log->stats[type].flush += log_buf_state_local.flush_to_file;
-		new_overflow = guc_check_log_buf_overflow(log, type, full_cnt);
+		new_overflow = intel_guc_check_log_buf_overflow(log, type, full_cnt);
 
 		/* Update the state of shared log buffer */
 		log_buf_state->read_ptr = write_offset;

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

@@ -67,6 +67,10 @@ struct intel_guc_log {
 };
 
 void intel_guc_log_init_early(struct intel_guc_log *log);
+bool intel_guc_check_log_buf_overflow(struct intel_guc_log *log, enum guc_log_buffer_type type,
+				      unsigned int full_cnt);
+unsigned int intel_guc_get_log_buffer_size(enum guc_log_buffer_type type);
+size_t intel_guc_get_log_buffer_offset(enum guc_log_buffer_type type);
 int intel_guc_log_create(struct intel_guc_log *log);
 void intel_guc_log_destroy(struct intel_guc_log *log);
 

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

@@ -25,6 +25,7 @@
 #include "gt/intel_ring.h"
 
 #include "intel_guc_ads.h"
+#include "intel_guc_capture.h"
 #include "intel_guc_submission.h"
 
 #include "i915_drv.h"
@@ -4095,17 +4096,18 @@ int intel_guc_context_reset_process_msg(struct intel_guc *guc,
 int intel_guc_error_capture_process_msg(struct intel_guc *guc,
 					const u32 *msg, u32 len)
 {
-	int status;
+	u32 status;
 
 	if (unlikely(len != 1)) {
 		drm_dbg(&guc_to_gt(guc)->i915->drm, "Invalid length %u", len);
 		return -EPROTO;
 	}
 
-	status = msg[0];
-	drm_info(&guc_to_gt(guc)->i915->drm, "Got error capture: status = %d", status);
+	status = msg[0] & INTEL_GUC_STATE_CAPTURE_EVENT_STATUS_MASK;
+	if (status == INTEL_GUC_STATE_CAPTURE_EVENT_STATUS_NOSPACE)
+		drm_warn(&guc_to_gt(guc)->i915->drm, "G2H-Error capture no space");
 
-	/* FIXME: Do something with the capture */
+	intel_guc_capture_process(guc);
 
 	return 0;
 }