Commit dbc9a5fb authored by Umesh Nerlige Ramappa's avatar Umesh Nerlige Ramappa
Browse files

drm/i915/perf: Parse 64bit report header formats correctly 



Now that OA formats come in flavor of 64 bit reports, the report header
has 64 bit report-id, timestamp, context-id and gpu-ticks fields. When
filtering these reports, use the right width for these fields.

Note that upper dword of context id is reserved, so squash lower dword
only.

v2: (Ashutosh)
- Drop inline
- Update comment with dword definitions - report id and timestamp

Signed-off-by: default avatarUmesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: default avatarAshutosh Dixit <ashutosh.dixit@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230323225901.3743681-7-umesh.nerlige.ramappa@intel.com
parent 772a5803

drivers/gpu/drm/i915/i915_perf.c

+84 −25
Original line number Diff line number Diff line
@@ -441,6 +441,67 @@ static u32 gen7_oa_hw_tail_read(struct i915_perf_stream *stream) 
	return oastatus1 & GEN7_OASTATUS1_TAIL_MASK;

}



#define oa_report_header_64bit(__s) \

	((__s)->oa_buffer.format->header == HDR_64_BIT)



static u64 oa_report_id(struct i915_perf_stream *stream, void *report)

{

	return oa_report_header_64bit(stream) ? *(u64 *)report : *(u32 *)report;

}



static u64 oa_report_reason(struct i915_perf_stream *stream, void *report)

{

	return (oa_report_id(stream, report) >> OAREPORT_REASON_SHIFT) &

	       (GRAPHICS_VER(stream->perf->i915) == 12 ?

		OAREPORT_REASON_MASK_EXTENDED :

		OAREPORT_REASON_MASK);

}



static void oa_report_id_clear(struct i915_perf_stream *stream, u32 *report)

{

	if (oa_report_header_64bit(stream))

		*(u64 *)report = 0;

	else

		*report = 0;

}



static bool oa_report_ctx_invalid(struct i915_perf_stream *stream, void *report)

{

	return !(oa_report_id(stream, report) &

	       stream->perf->gen8_valid_ctx_bit) &&

	       GRAPHICS_VER(stream->perf->i915) <= 11;

}



static u64 oa_timestamp(struct i915_perf_stream *stream, void *report)

{

	return oa_report_header_64bit(stream) ?

		*((u64 *)report + 1) :

		*((u32 *)report + 1);

}



static void oa_timestamp_clear(struct i915_perf_stream *stream, u32 *report)

{

	if (oa_report_header_64bit(stream))

		*(u64 *)&report[2] = 0;

	else

		report[1] = 0;

}



static u32 oa_context_id(struct i915_perf_stream *stream, u32 *report)

{

	u32 ctx_id = oa_report_header_64bit(stream) ? report[4] : report[2];



	return ctx_id & stream->specific_ctx_id_mask;

}



static void oa_context_id_squash(struct i915_perf_stream *stream, u32 *report)

{

	if (oa_report_header_64bit(stream))

		report[4] = INVALID_CTX_ID;

	else

		report[2] = INVALID_CTX_ID;

}



/**

 * oa_buffer_check_unlocked - check for data and update tail ptr state

 * @stream: i915 stream instance
@@ -509,21 +570,22 @@ static bool oa_buffer_check_unlocked(struct i915_perf_stream *stream) 
		hw_tail -= gtt_offset;

		tail = hw_tail;



		/* Walk the stream backward until we find a report with dword 0

		 * & 1 not at 0. Since the circular buffer pointers progress by

		 * increments of 64 bytes and that reports can be up to 256

		 * bytes long, we can't tell whether a report has fully landed

		 * in memory before the first 2 dwords of the following report

		 * have effectively landed.

		/* Walk the stream backward until we find a report with report

		 * id and timestmap not at 0. Since the circular buffer pointers

		 * progress by increments of 64 bytes and that reports can be up

		 * to 256 bytes long, we can't tell whether a report has fully

		 * landed in memory before the report id and timestamp of the

		 * following report have effectively landed.

		 *

		 * This is assuming that the writes of the OA unit land in

		 * memory in the order they were written to.

		 * If not : (╯°□°）╯︵ ┻━┻

		 */

		while (OA_TAKEN(tail, aged_tail) >= report_size) {

			u32 *report32 = (void *)(stream->oa_buffer.vaddr + tail);

			void *report = stream->oa_buffer.vaddr + tail;



			if (report32[0] != 0 || report32[1] != 0)

			if (oa_report_id(stream, report) ||

			    oa_timestamp(stream, report))

				break;



			tail = (tail - report_size) & (OA_BUFFER_SIZE - 1);
@@ -702,7 +764,7 @@ static int gen8_append_oa_reports(struct i915_perf_stream *stream, 
		u8 *report = oa_buf_base + head;

		u32 *report32 = (void *)report;

		u32 ctx_id;

		u32 reason;

		u64 reason;



		/*

		 * All the report sizes factor neatly into the buffer
@@ -725,16 +787,12 @@ static int gen8_append_oa_reports(struct i915_perf_stream *stream, 
		 * triggered this specific report (mostly timer

		 * triggered or e.g. due to a context switch).

		 *

		 * This field is never expected to be zero so we can

		 * check that the report isn't invalid before copying

		 * it to userspace...

		 * In MMIO triggered reports, some platforms do not set the

		 * reason bit in this field and it is valid to have a reason

		 * field of zero.

		 */

		reason = ((report32[0] >> OAREPORT_REASON_SHIFT) &

			  (GRAPHICS_VER(stream->perf->i915) == 12 ?

			   OAREPORT_REASON_MASK_EXTENDED :

			   OAREPORT_REASON_MASK));



		ctx_id = report32[2] & stream->specific_ctx_id_mask;

		reason = oa_report_reason(stream, report);

		ctx_id = oa_context_id(stream, report32);



		/*

		 * Squash whatever is in the CTX_ID field if it's marked as
@@ -744,9 +802,10 @@ static int gen8_append_oa_reports(struct i915_perf_stream *stream, 
		 * Note: that we don't clear the valid_ctx_bit so userspace can

		 * understand that the ID has been squashed by the kernel.

		 */

		if (!(report32[0] & stream->perf->gen8_valid_ctx_bit) &&

		    GRAPHICS_VER(stream->perf->i915) <= 11)

			ctx_id = report32[2] = INVALID_CTX_ID;

		if (oa_report_ctx_invalid(stream, report)) {

			ctx_id = INVALID_CTX_ID;

			oa_context_id_squash(stream, report32);

		}



		/*

		 * NB: For Gen 8 the OA unit no longer supports clock gating
@@ -790,7 +849,7 @@ static int gen8_append_oa_reports(struct i915_perf_stream *stream, 
			 */

			if (stream->ctx &&

			    stream->specific_ctx_id != ctx_id) {

				report32[2] = INVALID_CTX_ID;

				oa_context_id_squash(stream, report32);

			}



			ret = append_oa_sample(stream, buf, count, offset,
@@ -802,11 +861,11 @@ static int gen8_append_oa_reports(struct i915_perf_stream *stream, 
		}



		/*

		 * Clear out the first 2 dword as a mean to detect unlanded

		 * Clear out the report id and timestamp as a means to detect unlanded

		 * reports.

		 */

		report32[0] = 0;

		report32[1] = 0;

		oa_report_id_clear(stream, report32);

		oa_timestamp_clear(stream, report32);

	}



	if (start_offset != *offset) {

drivers/gpu/drm/i915/i915_perf_types.h

+6 −0
Original line number Diff line number Diff line
@@ -38,9 +38,15 @@ enum { 
	PERF_GROUP_INVALID = U32_MAX,

};



enum report_header {

	HDR_32_BIT = 0,

	HDR_64_BIT,

};



struct i915_oa_format {

	u32 format;

	int size;

	enum report_header header;

};



struct i915_oa_reg {