[Intel-gfx] [PATCH v3] drm/i915/perf: Do not parse context image for HSW

[Umesh Nerlige Ramappa]

An earlier commit introduced a mechanism to parse the context image to
find the OA context control offset. This resulted in an NPD on haswell
when gem_context was passed into i915_perf_open_ioctl params. Haswell
does not support logical ring contexts, so ensure that the context image
is parsed only for platforms with logical ring contexts and also
validate lrc_reg_state.

v2: Fix build failure
v3: Fix checkpatch error

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/7432
Fixes: a5c3a3cbf029 ("drm/i915/perf: Determine gen12 oa ctx offset at runtime")
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa at intel.com>
Reviewed-by: Ashutosh Dixit <ashutosh.dixit at intel.com>
---
 drivers/gpu/drm/i915/i915_perf.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 00e09bb18b13..125b6ca25a75 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -1383,6 +1383,9 @@ static u32 oa_context_image_offset(struct intel_context *ce, u32 reg)
 	u32 offset, len = (ce->engine->context_size - PAGE_SIZE) / 4;
 	u32 *state = ce->lrc_reg_state;
 
+	if (drm_WARN_ON(&ce->engine->i915->drm, !state))
+		return U32_MAX;
+
 	for (offset = 0; offset < len; ) {
 		if (IS_MI_LRI_CMD(state[offset])) {
 			/*
@@ -1447,7 +1450,8 @@ static int oa_get_render_ctx_id(struct i915_perf_stream *stream)
 	if (IS_ERR(ce))
 		return PTR_ERR(ce);
 
-	if (engine_supports_mi_query(stream->engine)) {
+	if (engine_supports_mi_query(stream->engine) &&
+	    HAS_LOGICAL_RING_CONTEXTS(stream->perf->i915)) {
 		/*
 		 * We are enabling perf query here. If we don't find the context
 		 * offset here, just return an error.
-- 
2.36.1