radv: rework the TC-compat HTILE hardware bug with COND_EXEC

After investigating on this, it appears that COND_WRITE doesn't
work correctly in some situations. I don't know exactly why does
it fail to update DB_Z_INFO.ZRANGE_PRECISION, but as AMDVLK
also uses COND_EXEC I think there is a reason.

Now the driver stores a new metadata value in order to reflect
the last fast depth clear state. If a TC-compat HTILE is fast cleared
with 0.0f, we have to update ZRANGE_PRECISION to 0 in order to
work around that hardware bug.

This fixes rendering issues with The Forest and DXVK and doesn't
seem to introduce any regressions.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108914
Fixes: 68dead112e7 ("radv: update the ZRANGE_PRECISION value for the TC-compat bug")
Signed-off-by: Samuel Pitoiset <[email protected]>
Reviewed-by: Bas Nieuwenhuizen <[email protected]>

3 files changed, 81 insertions, 28 deletions

diff --git a/src/amd/vulkan/radv_cmd_buffer.c b/src/amd/vulkan/radv_cmd_buffer.c
index ccf762ead46..23909a0f7dd 100644
--- a/src/amd/vulkan/radv_cmd_buffer.c
+++ b/src/amd/vulkan/radv_cmd_buffer.c
@@ -1067,7 +1067,7 @@ static void
 radv_update_zrange_precision(struct radv_cmd_buffer *cmd_buffer,
 			     struct radv_ds_buffer_info *ds,
 			     struct radv_image *image, VkImageLayout layout,
-			     bool requires_cond_write)
+			     bool requires_cond_exec)
 {
 	uint32_t db_z_info = ds->db_z_info;
 	uint32_t db_z_info_reg;
@@ -1091,38 +1091,21 @@ radv_update_zrange_precision(struct radv_cmd_buffer *cmd_buffer,
 	}
 
 	/* When we don't know the last fast clear value we need to emit a
-	 * conditional packet, otherwise we can update DB_Z_INFO directly.
+	 * conditional packet that will eventually skip the following
+	 * SET_CONTEXT_REG packet.
 	 */
-	if (requires_cond_write) {
-		radeon_emit(cmd_buffer->cs, PKT3(PKT3_COND_WRITE, 7, 0));
-
-		const uint32_t write_space = 0 << 8;	/* register */
-		const uint32_t poll_space = 1 << 4;	/* memory */
-		const uint32_t function = 3 << 0;	/* equal to the reference */
-		const uint32_t options = write_space | poll_space | function;
-		radeon_emit(cmd_buffer->cs, options);
-
-		/* poll address - location of the depth clear value */
+	if (requires_cond_exec) {
 		uint64_t va = radv_buffer_get_va(image->bo);
-		va += image->offset + image->clear_value_offset;
-
-		/* In presence of stencil format, we have to adjust the base
-		 * address because the first value is the stencil clear value.
-		 */
-		if (vk_format_is_stencil(image->vk_format))
-			va += 4;
+		va += image->offset + image->tc_compat_zrange_offset;
 
+		radeon_emit(cmd_buffer->cs, PKT3(PKT3_COND_EXEC, 3, 0));
 		radeon_emit(cmd_buffer->cs, va);
 		radeon_emit(cmd_buffer->cs, va >> 32);
-
-		radeon_emit(cmd_buffer->cs, fui(0.0f));		 /* reference value */
-		radeon_emit(cmd_buffer->cs, (uint32_t)-1);	 /* comparison mask */
-		radeon_emit(cmd_buffer->cs, db_z_info_reg >> 2); /* write address low */
-		radeon_emit(cmd_buffer->cs, 0u);		 /* write address high */
-		radeon_emit(cmd_buffer->cs, db_z_info);
-	} else {
-		radeon_set_context_reg(cmd_buffer->cs, db_z_info_reg, db_z_info);
+		radeon_emit(cmd_buffer->cs, 0);
+		radeon_emit(cmd_buffer->cs, 3); /* SET_CONTEXT_REG size */
 	}
+
+	radeon_set_context_reg(cmd_buffer->cs, db_z_info_reg, db_z_info);
 }
 
 static void
@@ -1270,6 +1253,45 @@ radv_set_ds_clear_metadata(struct radv_cmd_buffer *cmd_buffer,
 }
 
 /**
+ * Update the TC-compat metadata value for this image.
+ */
+static void
+radv_set_tc_compat_zrange_metadata(struct radv_cmd_buffer *cmd_buffer,
+				   struct radv_image *image,
+				   uint32_t value)
+{
+	struct radeon_cmdbuf *cs = cmd_buffer->cs;
+	uint64_t va = radv_buffer_get_va(image->bo);
+	va += image->offset + image->tc_compat_zrange_offset;
+
+	radeon_emit(cs, PKT3(PKT3_WRITE_DATA, 3, 0));
+	radeon_emit(cs, S_370_DST_SEL(V_370_MEM_ASYNC) |
+			S_370_WR_CONFIRM(1) |
+			S_370_ENGINE_SEL(V_370_PFP));
+	radeon_emit(cs, va);
+	radeon_emit(cs, va >> 32);
+	radeon_emit(cs, value);
+}
+
+static void
+radv_update_tc_compat_zrange_metadata(struct radv_cmd_buffer *cmd_buffer,
+				      struct radv_image *image,
+				      VkClearDepthStencilValue ds_clear_value)
+{
+	struct radeon_cmdbuf *cs = cmd_buffer->cs;
+	uint64_t va = radv_buffer_get_va(image->bo);
+	va += image->offset + image->tc_compat_zrange_offset;
+	uint32_t cond_val;
+
+	/* Conditionally set DB_Z_INFO.ZRANGE_PRECISION to 0 when the last
+	 * depth clear value is 0.0f.
+	 */
+	cond_val = ds_clear_value.depth == 0.0f ? UINT_MAX : 0;
+
+	radv_set_tc_compat_zrange_metadata(cmd_buffer, image, cond_val);
+}
+
+/**
  * Update the clear depth/stencil values for this image.
  */
 void
@@ -1282,6 +1304,12 @@ radv_update_ds_clear_metadata(struct radv_cmd_buffer *cmd_buffer,
 
 	radv_set_ds_clear_metadata(cmd_buffer, image, ds_clear_value, aspects);
 
+	if (radv_image_is_tc_compat_htile(image) &&
+	    (aspects & VK_IMAGE_ASPECT_DEPTH_BIT)) {
+		radv_update_tc_compat_zrange_metadata(cmd_buffer, image,
+						      ds_clear_value);
+	}
+
 	radv_update_bound_fast_clear_ds(cmd_buffer, image, ds_clear_value,
 				        aspects);
 }
@@ -4229,6 +4257,15 @@ static void radv_initialize_htile(struct radv_cmd_buffer *cmd_buffer,
 		aspects |= VK_IMAGE_ASPECT_STENCIL_BIT;
 
 	radv_set_ds_clear_metadata(cmd_buffer, image, value, aspects);
+
+	if (radv_image_is_tc_compat_htile(image)) {
+		/* Initialize the TC-compat metada value to 0 because by
+		 * default DB_Z_INFO.RANGE_PRECISION is set to 1, and we only
+		 * need have to conditionally update its value when performing
+		 * a fast depth clear.
+		 */
+		radv_set_tc_compat_zrange_metadata(cmd_buffer, image, 0);
+	}
 }
 
 static void radv_handle_depth_image_transition(struct radv_cmd_buffer *cmd_buffer,
diff --git a/src/amd/vulkan/radv_image.c b/src/amd/vulkan/radv_image.c
index 4032906f3c6..090ca70a327 100644
--- a/src/amd/vulkan/radv_image.c
+++ b/src/amd/vulkan/radv_image.c
@@ -870,6 +870,14 @@ radv_image_alloc_htile(struct radv_image *image)
 	/* + 8 for storing the clear values */
 	image->clear_value_offset = image->htile_offset + image->surface.htile_size;
 	image->size = image->clear_value_offset + 8;
+	if (radv_image_is_tc_compat_htile(image)) {
+		/* Metadata for the TC-compatible HTILE hardware bug which
+		 * have to be fixed by updating ZRANGE_PRECISION when doing
+		 * fast depth clears to 0.0f.
+		 */
+		image->tc_compat_zrange_offset = image->clear_value_offset + 8;
+		image->size = image->clear_value_offset + 16;
+	}
 	image->alignment = align64(image->alignment, image->surface.htile_alignment);
 }
 
@@ -1014,8 +1022,8 @@ radv_image_create(VkDevice _device,
 			/* Otherwise, try to enable HTILE for depth surfaces. */
 			if (radv_image_can_enable_htile(image) &&
 			    !(device->instance->debug_flags & RADV_DEBUG_NO_HIZ)) {
-				radv_image_alloc_htile(image);
 				image->tc_compatible_htile = image->surface.flags & RADEON_SURF_TC_COMPATIBLE_HTILE;
+				radv_image_alloc_htile(image);
 			} else {
 				image->surface.htile_size = 0;
 			}
diff --git a/src/amd/vulkan/radv_private.h b/src/amd/vulkan/radv_private.h
index ac756f2c247..8d69b016d6f 100644
--- a/src/amd/vulkan/radv_private.h
+++ b/src/amd/vulkan/radv_private.h
@@ -1503,6 +1503,14 @@ struct radv_image {
 	uint64_t clear_value_offset;
 	uint64_t fce_pred_offset;
 
+	/*
+	 * Metadata for the TC-compat zrange workaround. If the 32-bit value
+	 * stored at this offset is UINT_MAX, the driver will emit
+	 * DB_Z_INFO.ZRANGE_PRECISION=0, otherwise it will skip the
+	 * SET_CONTEXT_REG packet.
+	 */
+	uint64_t tc_compat_zrange_offset;
+
 	/* For VK_ANDROID_native_buffer, the WSI image owns the memory, */
 	VkDeviceMemory owned_memory;
 };