drm/i915: Don't use MI_STORE_DWORD_IMM on Sandybridge/vcs

MI_STORE_DWORD_IMM just doesn't work on the video decode engine under
Sandybridge, so refrain from using it. Then switch the selftests over to
using the now common test prior to using MI_STORE_DWORD_IMM.

Fixes: 7dd4f6729f ("drm/i915: Async GPU relocation processing")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.13-rc1+
Link: https://patchwork.freedesktop.org/patch/msgid/20170816085210.4199-1-chris@chris-wilson.co.uk
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>

drivers/gpu/drm/i915/i915_drv.h

@@ -4328,4 +4328,11 @@ int remap_io_mapping(struct vm_area_struct *vma,
 		     unsigned long addr, unsigned long pfn, unsigned long size,
 		     struct io_mapping *iomap);
 
+static inline bool
+intel_engine_can_store_dword(struct intel_engine_cs *engine)
+{
+	return __intel_engine_can_store_dword(INTEL_GEN(engine->i915),
+					      engine->class);
+}
+
 #endif

drivers/gpu/drm/i915/i915_gem_execbuffer.c

@@ -1268,7 +1268,9 @@ relocate_entry(struct i915_vma *vma,
 
 	if (!eb->reloc_cache.vaddr &&
 	    (DBG_FORCE_RELOC == FORCE_GPU_RELOC ||
-	     !reservation_object_test_signaled_rcu(vma->resv, true))) {
+	     !reservation_object_test_signaled_rcu(vma->resv, true)) &&
+	    __intel_engine_can_store_dword(eb->reloc_cache.gen,
+					   eb->engine->class)) {
 		const unsigned int gen = eb->reloc_cache.gen;
 		unsigned int len;
 		u32 *batch;
@@ -1278,10 +1280,8 @@ relocate_entry(struct i915_vma *vma,
 			len = offset & 7 ? 8 : 5;
 		else if (gen >= 4)
 			len = 4;
-		else if (gen >= 3)
+		else
 			len = 3;
-		else /* On gen2 MI_STORE_DWORD_IMM uses a physical address */
-			goto repeat;
 
 		batch = reloc_gpu(eb, vma, len);
 		if (IS_ERR(batch))

drivers/gpu/drm/i915/i915_selftest.h

@@ -101,6 +101,4 @@ bool __igt_timeout(unsigned long timeout, const char *fmt, ...);
 #define igt_timeout(t, fmt, ...) \
 	__igt_timeout((t), KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
 
-#define igt_can_mi_store_dword_imm(D) (INTEL_GEN(D) > 2)
-
 #endif /* !__I915_SELFTEST_H__ */

drivers/gpu/drm/i915/intel_ringbuffer.h

@@ -735,4 +735,16 @@ bool intel_engines_are_idle(struct drm_i915_private *dev_priv);
 void intel_engines_mark_idle(struct drm_i915_private *i915);
 void intel_engines_reset_default_submission(struct drm_i915_private *i915);
 
+static inline bool
+__intel_engine_can_store_dword(unsigned int gen, unsigned int class)
+{
+	if (gen <= 2)
+		return false; /* uses physical not virtual addresses */
+
+	if (gen == 6 && class == VIDEO_DECODE_CLASS)
+		return false; /* b0rked */
+
+	return true;
+}
+
 #endif /* _INTEL_RINGBUFFER_H_ */

drivers/gpu/drm/i915/selftests/i915_gem_coherency.c

@@ -241,7 +241,7 @@ static bool always_valid(struct drm_i915_private *i915)
 
 static bool needs_mi_store_dword(struct drm_i915_private *i915)
 {
-	return igt_can_mi_store_dword_imm(i915);
+	return intel_engine_can_store_dword(i915->engine[RCS]);
 }
 
 static const struct igt_coherency_mode {

drivers/gpu/drm/i915/selftests/i915_gem_context.c

@@ -38,8 +38,6 @@ gpu_fill_dw(struct i915_vma *vma, u64 offset, unsigned long count, u32 value)
 	u32 *cmd;
 	int err;
 
-	GEM_BUG_ON(!igt_can_mi_store_dword_imm(vma->vm->i915));
-
 	size = (4 * count + 1) * sizeof(u32);
 	size = round_up(size, PAGE_SIZE);
 	obj = i915_gem_object_create_internal(vma->vm->i915, size);
@@ -123,6 +121,7 @@ static int gpu_fill(struct drm_i915_gem_object *obj,
 	int err;
 
 	GEM_BUG_ON(obj->base.size > vm->total);
+	GEM_BUG_ON(!intel_engine_can_store_dword(engine));
 
 	vma = i915_vma_instance(obj, vm, NULL);
 	if (IS_ERR(vma))
@@ -359,6 +358,9 @@ static int igt_ctx_exec(void *arg)
 		}
 
 		for_each_engine(engine, i915, id) {
+			if (!intel_engine_can_store_dword(engine))
+				continue;
+
 			if (!obj) {
 				obj = create_test_object(ctx, file, &objects);
 				if (IS_ERR(obj)) {

drivers/gpu/drm/i915/selftests/intel_hangcheck.c

@@ -253,9 +253,6 @@ static int igt_hang_sanitycheck(void *arg)
 
 	/* Basic check that we can execute our hanging batch */
 
-	if (!igt_can_mi_store_dword_imm(i915))
-		return 0;
-
 	mutex_lock(&i915->drm.struct_mutex);
 	err = hang_init(&h, i915);
 	if (err)
@@ -264,6 +261,9 @@ static int igt_hang_sanitycheck(void *arg)
 	for_each_engine(engine, i915, id) {
 		long timeout;
 
+		if (!intel_engine_can_store_dword(engine))
+			continue;
+
 		rq = hang_create_request(&h, engine, i915->kernel_context);
 		if (IS_ERR(rq)) {
 			err = PTR_ERR(rq);
@@ -599,6 +599,9 @@ static int igt_wait_reset(void *arg)
 	long timeout;
 	int err;
 
+	if (!intel_engine_can_store_dword(i915->engine[RCS]))
+		return 0;
+
 	/* Check that we detect a stuck waiter and issue a reset */
 
 	global_reset_lock(i915);
@@ -664,9 +667,6 @@ static int igt_reset_queue(void *arg)
 
 	/* Check that we replay pending requests following a hang */
 
-	if (!igt_can_mi_store_dword_imm(i915))
-		return 0;
-
 	global_reset_lock(i915);
 
 	mutex_lock(&i915->drm.struct_mutex);
@@ -679,6 +679,9 @@ static int igt_reset_queue(void *arg)
 		IGT_TIMEOUT(end_time);
 		unsigned int count;
 
+		if (!intel_engine_can_store_dword(engine))
+			continue;
+
 		prev = hang_create_request(&h, engine, i915->kernel_context);
 		if (IS_ERR(prev)) {
 			err = PTR_ERR(prev);
@@ -784,6 +787,9 @@ static int igt_handle_error(void *arg)
 	if (!intel_has_reset_engine(i915))
 		return 0;
 
+	if (!intel_engine_can_store_dword(i915->engine[RCS]))
+		return 0;
+
 	mutex_lock(&i915->drm.struct_mutex);
 
 	err = hang_init(&h, i915);