drm/i915/i915_perf.c

124  *   and while we could pull a report out of the OA buffer we can't
125  *   trigger a report from the cpu on demand.
127  *   Related to being report based; the OA counters are configured in HW as a
132  *   OA unit report format used to capture all counters in a set, or specify a
148  *     With the OA unit's report formats, counters are packed together as 32
149  *     or 40bit values, with the largest report size being 256 bytes.
173  *   ring buffer. To include more than the OA report we'd have to copy the
174  *   report into an intermediate larger buffer. I'd been considering allowing a
188  *   majority of the OA driver ran in atomic context, including all OA report
240  * by checking for a zeroed report-id field in tail reports, we want to account
246  * report with its first 2 dwords not 0 meaning its previous report is
249  * first dword is the reason for this report while the second is the timestamp,
281  * overflow in OA report timestamps.
314 /* XXX: beware if future OA HW adds new report formats that the current
350  * @oa_format: An OA unit HW report format
462 static u64 oa_report_id(struct i915_perf_stream *stream, void *report)
464 	return oa_report_header_64bit(stream) ? *(u64 *)report : *(u32 *)report;
467 static u64 oa_report_reason(struct i915_perf_stream *stream, void *report)
469 	return (oa_report_id(stream, report) >> OAREPORT_REASON_SHIFT) &
475 static void oa_report_id_clear(struct i915_perf_stream *stream, u32 *report)
478 		*(u64 *)report = 0;
480 		*report = 0;
483 static bool oa_report_ctx_invalid(struct i915_perf_stream *stream, void *report)
485 	return !(oa_report_id(stream, report) &
489 static u64 oa_timestamp(struct i915_perf_stream *stream, void *report)
492 		*((u64 *)report + 1) :
493 		*((u32 *)report + 1);
496 static void oa_timestamp_clear(struct i915_perf_stream *stream, u32 *report)
499 		*(u64 *)&report[2] = 0;
501 		report[1] = 0;
504 static u32 oa_context_id(struct i915_perf_stream *stream, u32 *report)
506 	u32 ctx_id = oa_report_header_64bit(stream) ? report[4] : report[2];
511 static void oa_context_id_squash(struct i915_perf_stream *stream, u32 *report)
514 		report[4] = INVALID_CTX_ID;
516 		report[2] = INVALID_CTX_ID;
561 	 * steps. Also the report size may not be a power of 2. Compute
562 	 * potentially partially landed report in the OA buffer
572 	/* Walk the stream backward until we find a report with report
575 	 * to 256 bytes long, we can't tell whether a report has fully
576 	 * landed in memory before the report id and timestamp of the
577 	 * following report have effectively landed.
584 		void *report = stream->oa_buffer.vaddr + tail;
586 		if (oa_report_id(stream, report) ||
587 		    oa_timestamp(stream, report))
596 			   "unlanded report(s) head=0x%x tail=0x%x hw_tail=0x%x\n",
615  * @type: The kind of status to report to userspace
644  * append_oa_sample - Copies single OA report into userspace read() buffer.
649  * @report: A single OA report to (optionally) include as part of the sample
664 			    const u8 *report)
684 	report_size_partial = oa_buf_end - report;
687 		if (copy_to_user(buf, report, report_size_partial))
694 	} else if (copy_to_user(buf, report, report_size)) {
753 	 * only be incremented by multiples of the report size.
766 		u8 *report = oa_buf_base + head;
767 		u32 *report32 = (void *)report;
773 		 * triggered this specific report (mostly timer
776 		reason = oa_report_reason(stream, report);
793 		 * context-switch-report: This is a report with the reason type
797 		 * context-valid-bit: A bit that is set in the report ID field
801 		 * context-switch-report with context-valid-bit set to 0.
807 		 * switch report if a new context switched in. For all other
813 		 * below to squash the context ID would render the report
819 		if (oa_report_ctx_invalid(stream, report) &&
854 		 * identify a switch before any 'context switch' report.
871 					       report);
880 			 * Clear out the report id and timestamp as a means
890 			/* Zero out the entire report */
1062 	 * only be incremented by multiples of the report size (notably also
1076 		u8 *report = oa_buf_base + head;
1077 		u32 *report32 = (void *)report;
1079 		/* All the report sizes factor neatly into the buffer
1080 		 * size so we never expect to see a report split
1090 				"Spurious OA head ptr: non-integral report offset\n");
1094 		/* The report-ID field for periodic samples includes
1096 		 * the report and is never expected to be zero so we
1097 		 * can check that the report isn't invalid before
1103 					   "Skipping spurious, invalid OA report\n");
1107 		ret = append_oa_sample(stream, buf, count, offset, report);
1173 	 *   which will start to report a near-empty buffer after an
1691 		gt_notice(gt, "%d spurious OA report notices suppressed due to ratelimiting\n",
1734 	 * report-id field to make sure it's non-zero which relies on
3291 			"Only OA report sampling supported\n");
3314 			"OA report format not specified\n");
3479 		 * oabuffer has >= 1 report we don't immediately know whether
3497 	/* We allow the poll checking to sometimes report false positive EPOLLIN
3498 	 * events where we might actually report EAGAIN on read() if there's
4069 					"Out-of-range OA report format %llu\n",
4075 					"Unsupported OA report format %llu\n",