75  * the constraints on HW configuration require reports to be filtered before it
114  *   The OA unit writes reports of counters into a circular buffer, without
134  *   feature and forwarded OA reports to userspace via perf's 'raw' sample
138  *   them. For Mesa it's also convenient to be forwarded raw, periodic reports
139  *   for combining with the side-band raw reports it captures using
169  *   attach GPU timestamps to our OA samples. We were shoehorning OA reports
227  * Although this can be observed explicitly while copying reports to userspace
228  * by checking for a zeroed report-id field in tail reports, we want to account
232  * We workaround this issue in oa_buffer_check_unlocked() by reading the reports
248  * non-periodic reports (such as on context switch) or the OA unit may be
255  * reports to the circular OA buffer...
264  * of the 64bit timestamp bits to trigger reports from) but there's currently
267  * Since the timestamps included in OA reports are only 32bits it seems
275 /* On Gen8+ automatically triggered OA reports include a 'reason' field... */
302  * code assumes all reports have a power-of-two size and ~(size - 1) can
502 		 * increments of 64 bytes and that reports can be up to 256  in oa_buffer_check_unlocked()
620  * gen8_append_oa_reports - Copies all buffered OA reports into
633  * Note: reports are consumed from the head, and appended to the
746 		 * Automatic reports now include a context ID so reports can be  in gen8_append_oa_reports()
755 		 * needs be forwarded bookend context-switch reports so that it  in gen8_append_oa_reports()
759 		 * automatically triggers reports when switching to a new  in gen8_append_oa_reports()
762 		 * reading ahead while parsing reports to try and minimize  in gen8_append_oa_reports()
763 		 * forwarding redundant context switch reports (i.e. between  in gen8_append_oa_reports()
795 		 * reports.  in gen8_append_oa_reports()
825  * gen8_oa_read - copy status records then buffered OA reports
833  * initiate appending any buffered OA reports.
867 	 * automatically triggered reports in this condition and so we  in gen8_oa_read()
868 	 * have to assume that old reports are now being trampled  in gen8_oa_read()
913  * gen7_append_oa_reports - Copies all buffered OA reports into
926  * Note: reports are consumed from the head, and appended to the
1017 		 * reports.  in gen7_append_oa_reports()
1043  * gen7_oa_read - copy status records then buffered OA reports
1051  * condition) and then initiate appending any buffered OA reports.
1089 	 *   reports it may also affect our sanity checks for invalid  in gen7_oa_read()
1090 	 *   reports when copying to userspace that assume new reports  in gen7_oa_read()
1249 		 * On Haswell we don't do any post processing of the reports  in oa_get_render_ctx_id()
1268 			 * ID in the OA reports, so squash those lower bits.  in oa_get_render_ctx_id()
1439 	 * the assumption that new reports are being written to zeroed  in gen7_init_oa_buffer()
1477 	 * reports we will forward to userspace while filtering for a single  in gen8_init_oa_buffer()
1493 	 * the assumption that new reports are being written to zeroed  in gen8_init_oa_buffer()
1531 	 * reports we will forward to userspace while filtering for a single  in gen12_init_oa_buffer()
1547 	 * the assumption that new reports are being written to zeroed  in gen12_init_oa_buffer()
2481 	 * We disable slice/unslice clock ratio change reports on SKL since  in gen8_enable_metric_set()
2482 	 * they are too noisy. The HW generates a lot of redundant reports  in gen8_enable_metric_set()
2488 	 * feature it's worth noting that clock ratio reports have to be  in gen8_enable_metric_set()
2490 	 * correctly block these reports.  in gen8_enable_metric_set()
2500 	 * be read back from automatically triggered reports, as part of the  in gen8_enable_metric_set()
2541 			   /* Disable clk ratio reports, like previous Gens. */  in gen12_enable_metric_set()
2545 			    * If the user didn't require OA reports, instruct  in gen12_enable_metric_set()
2546 			    * the hardware not to emit ctx switch reports.  in gen12_enable_metric_set()
2627 	 * Reset buf pointers so we don't forward reports from before now.  in gen7_oa_enable()
2631 	 * in error paths, and we have checks for invalid reports based  in gen7_oa_enable()
2653 	 * Reset buf pointers so we don't forward reports from before now.  in gen8_oa_enable()
2657 	 * in error paths, and we have checks for invalid reports based  in gen8_oa_enable()
2666 	 * field of reports  in gen8_oa_enable()
2679 	 * If we don't want OA reports from the OA buffer, then we don't even  in gen12_oa_enable()
2762  * Stops the OA unit from periodically writing counter reports into the
2887 	 * counter reports and marshal to the appropriate client  in i915_oa_stream_init()
3062 		 * any reports really belong to the current context  in i915_perf_read()
3442 	 * filter reports based on the included context ID we can't block  in i915_perf_open_ioctl_locked()
4452 		 * _NOTES about spurious, invalid OA reports which we don't  in i915_perf_init()
4462 		/* Since we use a DRM_NOTE for spurious reports it would be  in i915_perf_init()
4535 	 *    accessible from a delta of MI_RPC reports without looking at the  in i915_perf_ioctl_version()