[PATCH] drm/i915/perf: Detect offset in context image for OA ctx control reg

[Umesh Nerlige Ramappa <umesh.nerlige.ramappa@xxxxxxxxx>]

Not for review. Just trying out a selftest on CI machines.

Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@xxxxxxxxx>
---
 drivers/gpu/drm/i915/selftests/i915_perf.c | 114 ++++++++++++++++++++-
 1 file changed, 113 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/selftests/i915_perf.c b/drivers/gpu/drm/i915/selftests/i915_perf.c
index 9e9a6cb1d9e5..67b230c867c6 100644
--- a/drivers/gpu/drm/i915/selftests/i915_perf.c
+++ b/drivers/gpu/drm/i915/selftests/i915_perf.c
@@ -8,6 +8,7 @@
 
 #include "gem/i915_gem_pm.h"
 #include "gt/intel_gt.h"
+#include "gt/intel_lrc_reg.h"
 
 #include "i915_selftest.h"
 
@@ -152,6 +153,111 @@ static int live_sanitycheck(void *arg)
 	return 0;
 }
 
+#define MI_OPCODE(x) (((x) >> 23) & 0x3f)
+#define MI_LRI_CMD(x) (MI_OPCODE(x) == MI_OPCODE(MI_INSTR(0x22, 0)))
+#define MI_LRI_LEN(x) (((x) & 0xff) + 1)
+static int __find_reg_in_lri(u32 *state, u32 reg, u32 *offset)
+{
+	u32 idx = *offset;
+	u32 len = MI_LRI_LEN(state[idx]) + idx;
+
+	idx++;
+	for (; idx < len; idx += 2)
+		if (state[idx] == reg)
+			break;
+
+	*offset = idx;
+	return state[idx] == reg;
+}
+
+static void __context_image_offset(struct intel_context *ce, u32 reg)
+{
+	u32 *state = ce->lrc_reg_state;
+	u32 len = (ce->engine->context_size - PAGE_SIZE) / 4;
+	u32 offset;
+
+	for (offset = 0; offset < len; ) {
+		if (MI_LRI_CMD(state[offset])) {
+			if (__find_reg_in_lri(state, reg, &offset))
+				break;
+		} else {
+			offset++;
+		}
+	}
+
+	if (offset < len)
+		printk(KERN_ALERT "OA: offset %08x for %08x\n", offset, reg);
+	else
+		printk(KERN_ALERT "OA: offset not found for %08x\n", reg);
+}
+
+static int __live_lrc_state(struct intel_engine_cs *engine,
+			    struct i915_vma *scratch)
+{
+	struct intel_context *ce;
+	struct i915_gem_ww_ctx ww;
+	i915_reg_t reg;
+	int err;
+
+	ce = intel_context_create(engine);
+	if (IS_ERR(ce))
+		return PTR_ERR(ce);
+
+	i915_gem_ww_ctx_init(&ww, false);
+retry:
+	err = i915_gem_object_lock(scratch->obj, &ww);
+	if (!err)
+		err = intel_context_pin_ww(ce, &ww);
+	if (err)
+		goto err_put;
+
+	reg = GEN12_OACTXCONTROL;
+	__context_image_offset(ce, i915_mmio_reg_offset(reg));
+
+	intel_context_unpin(ce);
+err_put:
+	if (err == -EDEADLK) {
+		err = i915_gem_ww_ctx_backoff(&ww);
+		if (!err)
+			goto retry;
+	}
+	i915_gem_ww_ctx_fini(&ww);
+	intel_context_put(ce);
+	return err;
+}
+
+static int __live_oactxctrl_offset(void *arg)
+{
+	struct drm_i915_private *i915 = arg;
+	struct intel_gt *gt = &i915->gt;
+	struct intel_engine_cs *engine;
+	struct i915_vma *scratch;
+	enum intel_engine_id id;
+	int err = 0;
+
+	if (!HAS_LOGICAL_RING_CONTEXTS(i915))
+		return 0;
+
+	scratch = __vm_create_scratch_for_read_pinned(&gt->ggtt->vm, PAGE_SIZE);
+	if (IS_ERR(scratch))
+		return PTR_ERR(scratch);
+
+	for_each_engine(engine, gt, id) {
+		if (engine->class != RENDER_CLASS)
+			continue;
+
+		err = __live_lrc_state(engine, scratch);
+		if (err)
+			break;
+	}
+
+	if (igt_flush_test(gt->i915))
+		err = -EIO;
+
+	i915_vma_unpin_and_release(&scratch, 0);
+	return err;
+}
+
 static int write_timestamp(struct i915_request *rq, int slot)
 {
 	u32 *cs;
@@ -188,7 +294,7 @@ static ktime_t poll_status(struct i915_request *rq, int slot)
 	return ktime_get();
 }
 
-static int live_noa_delay(void *arg)
+static int __live_noa_delay(void *arg)
 {
 	struct drm_i915_private *i915 = arg;
 	struct i915_perf_stream *stream;
@@ -280,6 +386,12 @@ static int live_noa_delay(void *arg)
 	return err;
 }
 
+static int live_noa_delay(void *arg)
+{
+	__live_oactxctrl_offset(arg);
+	return __live_noa_delay(arg);
+}
+
 static int live_noa_gpr(void *arg)
 {
 	struct drm_i915_private *i915 = arg;
-- 
2.20.1