[Intel-gfx] [PATCH 12/19] drm/i915/perf: Parse 64bit report header formats correctly

Umesh Nerlige Ramappa
2022-08-23T20:42:20Z

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.

v2: Let compiler decide on inline (Jani)

Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
---
drivers/gpu/drm/i915/i915_perf.c | 101 ++++++++++++++++++++-----
drivers/gpu/drm/i915/i915_perf_types.h | 6 ++
2 files changed, 86 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 9e455bd3bce5..167e7355980a 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -324,8 +324,8 @@ static const struct i915_oa_format oa_formats[I915_OA_FORMAT_MAX] = {
[I915_OA_FORMAT_A32u40_A4u32_B8_C8] = { 5, 256 },
[I915_OAR_FORMAT_A32u40_A4u32_B8_C8] = { 5, 256 },
[I915_OA_FORMAT_A24u40_A14u32_B8_C8] = { 5, 256 },
- [I915_OAR_FORMAT_A36u64_B8_C8] = { 1, 384 },
- [I915_OA_FORMAT_A38u64_R2u64_B8_C8] = { 1, 448 },
+ [I915_OAR_FORMAT_A36u64_B8_C8] = { 1, 384, HDR_64_BIT },
+ [I915_OA_FORMAT_A38u64_R2u64_B8_C8] = { 1, 448, HDR_64_BIT },
};

#define SAMPLE_OA_REPORT (1<<0)
@@ -456,6 +456,67 @@ 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
@@ -545,9 +606,10 @@ static bool oa_buffer_check_unlocked(struct i915_perf_stream *stream)
* If not : (╯°□°）╯︵ ┻━┻
*/
while (_oa_taken(stream, 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 = _rewind_tail(stream, tail, report_size);
@@ -740,23 +802,19 @@ 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;

/*
* The reason field includes flags identifying what
* 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
@@ -766,9 +824,10 @@ 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
@@ -812,7 +871,7 @@ 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,
@@ -824,11 +883,11 @@ 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) {
diff --git a/drivers/gpu/drm/i915/i915_perf_types.h b/drivers/gpu/drm/i915/i915_perf_types.h
index e0c96b44eda8..68db5f94bc58 100644
--- a/drivers/gpu/drm/i915/i915_perf_types.h
+++ b/drivers/gpu/drm/i915/i915_perf_types.h
@@ -30,9 +30,15 @@ struct i915_vma;
struct intel_context;
struct intel_engine_cs;

+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 {
--
2.25.1