drm/xe/guc: Extract GuC error capture lists

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 devcoredump, duplicate global and engine-class register
lists for each engine-instance register dump if we find
dependent-engine resets in a engine-capture-group.

To avoid dynamically allocate the output nodes during gt reset,
pre-allocate a fixed number of empty nodes up front (at the
time of ADS registration) that we can consume from or return to
an internal cached list of nodes.

Signed-off-by: Zhanjun Dong <[email protected]>
Reviewed-by: Alan Previn <[email protected]>
Signed-off-by: Matt Roper <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

Author: zhanjun

drivers/gpu/drm/xe/abi/guc_actions_abi.h

@@ -176,6 +176,14 @@ enum xe_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 xe_guc_state_capture_event_status {
+	XE_GUC_STATE_CAPTURE_EVENT_STATUS_SUCCESS = 0x0,
+	XE_GUC_STATE_CAPTURE_EVENT_STATUS_NOSPACE = 0x1,
+};
+
+#define XE_GUC_STATE_CAPTURE_EVENT_STATUS_MASK      0x000000FF
+#define XE_GUC_ACTION_STATE_CAPTURE_NOTIFICATION_DATA_LEN 1
+
 #define XE_GUC_TLB_INVAL_TYPE_SHIFT 0
 #define XE_GUC_TLB_INVAL_MODE_SHIFT 8
 /* Flush PPC or SMRO caches along with TLB invalidation request */

drivers/gpu/drm/xe/abi/guc_log_abi.h

@@ -17,4 +17,59 @@ enum guc_log_buffer_type {
 
 #define GUC_LOG_BUFFER_TYPE_MAX		3
 
+/**
+ * struct guc_log_buffer_state - GuC log buffer state
+ *
+ * Below state structure is used for coordination of retrieval of GuC firmware
+ * logs. Separate state is maintained for each log buffer type.
+ * read_ptr points to the location where Xe read last in log buffer and
+ * is read only for GuC firmware. write_ptr is incremented by GuC with number
+ * of bytes written for each log entry and is read only for Xe.
+ * When any type of log buffer becomes half full, GuC sends a flush interrupt.
+ * GuC firmware expects that while it is writing to 2nd half of the buffer,
+ * first half would get consumed by Host and then get a flush completed
+ * acknowledgment from Host, so that it does not end up doing any overwrite
+ * causing loss of logs. So when buffer gets half filled & Xe has requested
+ * for interrupt, GuC will set flush_to_file field, set the sampled_write_ptr
+ * to the value of write_ptr and raise the interrupt.
+ * On receiving the interrupt Xe should read the buffer, clear flush_to_file
+ * field and also update read_ptr with the value of sample_write_ptr, before
+ * sending an acknowledgment to GuC. marker & version fields are for internal
+ * usage of GuC and opaque to Xe. buffer_full_cnt field is incremented every
+ * time GuC detects the log buffer overflow.
+ */
+struct guc_log_buffer_state {
+	/** @marker: buffer state start marker */
+	u32 marker[2];
+	/** @read_ptr: the last byte offset that was read by KMD previously */
+	u32 read_ptr;
+	/**
+	 * @write_ptr: the next byte offset location that will be written by
+	 * GuC
+	 */
+	u32 write_ptr;
+	/** @size: Log buffer size */
+	u32 size;
+	/**
+	 * @sampled_write_ptr: Log buffer write pointer
+	 * This is written by GuC to the byte offset of the next free entry in
+	 * the buffer on log buffer half full or state capture notification
+	 */
+	u32 sampled_write_ptr;
+	/**
+	 * @wrap_offset: wraparound offset
+	 * This is the byte offset of location 1 byte after last valid guc log
+	 * event entry written by Guc firmware before there was a wraparound.
+	 * This field is updated by guc firmware and should be used by Host
+	 * when copying buffer contents to file.
+	 */
+	u32 wrap_offset;
+	/** @flags: Flush to file flag and buffer full count */
+	u32 flags;
+#define	GUC_LOG_BUFFER_STATE_FLUSH_TO_FILE	GENMASK(0, 0)
+#define	GUC_LOG_BUFFER_STATE_BUFFER_FULL_CNT	GENMASK(4, 1)
+	/** @version: The Guc-Log-Entry format version */
+	u32 version;
+} __packed;
+
 #endif