[Mesa-dev] [PATCH 5/5] radv: enable DCC for MSAA 2x textures on VI under an option

[Samuel Pitoiset]

This can be enabled with RADV_PERFTEST=dccmsaa.

DCC for MSAA textures is actually not as easy to implement. It
looks like there is some corner cases. I will improve support
incrementally.

Vega support, as well as Polaris improvements, will be added later.

No CTS changes on Polaris using RADV_DEBUG=zerovram and
RADV_PERFTEST=dccmsaa.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
---
 src/amd/vulkan/radv_debug.h   | 1 +
 src/amd/vulkan/radv_device.c  | 4 ++++
 src/amd/vulkan/radv_image.c   | 6 +++++-
 src/amd/vulkan/radv_private.h | 3 +++
 4 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/amd/vulkan/radv_debug.h b/src/amd/vulkan/radv_debug.h
index f35991fa4e5..79c624aec1d 100644
--- a/src/amd/vulkan/radv_debug.h
+++ b/src/amd/vulkan/radv_debug.h
@@ -51,6 +51,7 @@ enum {
 	RADV_PERFTEST_LOCAL_BOS      =   0x4,
 	RADV_PERFTEST_BINNING     =   0x8,
 	RADV_PERFTEST_OUT_OF_ORDER   =  0x10,
+	RADV_PERFTEST_DCC_MSAA       =  0x20,
 };
 
 bool
diff --git a/src/amd/vulkan/radv_device.c b/src/amd/vulkan/radv_device.c
index b8313b26ebf..6e74e3cc2c9 100644
--- a/src/amd/vulkan/radv_device.c
+++ b/src/amd/vulkan/radv_device.c
@@ -314,6 +314,9 @@ radv_physical_device_init(struct radv_physical_device *device,
 	device->out_of_order_rast_allowed = device->has_out_of_order_rast &&
 					    (device->instance->perftest_flags & RADV_PERFTEST_OUT_OF_ORDER);
 
+	device->dcc_msaa_allowed = device->rad_info.chip_class == VI &&
+				   (device->instance->perftest_flags & RADV_PERFTEST_DCC_MSAA);
+
 	radv_physical_device_init_mem_types(device);
 	radv_fill_device_extension_table(device, &device->supported_extensions);
 
@@ -399,6 +402,7 @@ static const struct debug_control radv_perftest_options[] = {
 	{"localbos", RADV_PERFTEST_LOCAL_BOS},
 	{"binning", RADV_PERFTEST_BINNING},
 	{"outoforderrast", RADV_PERFTEST_OUT_OF_ORDER},
+	{"dccmsaa", RADV_PERFTEST_DCC_MSAA},
 	{NULL, 0}
 };
 
diff --git a/src/amd/vulkan/radv_image.c b/src/amd/vulkan/radv_image.c
index ba8f14d91bd..348f4c7b34c 100644
--- a/src/amd/vulkan/radv_image.c
+++ b/src/amd/vulkan/radv_image.c
@@ -133,8 +133,12 @@ radv_use_dcc_for_image(struct radv_device *device,
 	if (create_info->scanout)
 		return false;
 
+	/* FIXME: DCC for MSAA with 4x and 8x samples doesn't work yet. */
+	if (pCreateInfo->samples > 2)
+		return false;
+
 	/* TODO: Enable DCC for MSAA textures. */
-	if (pCreateInfo->samples >= 2)
+	if (!device->physical_device->dcc_msaa_allowed)
 		return false;
 
 	/* Determine if the formats are DCC compatible. */
diff --git a/src/amd/vulkan/radv_private.h b/src/amd/vulkan/radv_private.h
index 1869604e9e2..9950144a50a 100644
--- a/src/amd/vulkan/radv_private.h
+++ b/src/amd/vulkan/radv_private.h
@@ -295,6 +295,9 @@ struct radv_physical_device {
 	bool has_out_of_order_rast;
 	bool out_of_order_rast_allowed;
 
+	/* Whether DCC should be enabled for MSAA textures. */
+	bool dcc_msaa_allowed;
+
 	/* This is the drivers on-disk cache used as a fallback as opposed to
 	 * the pipeline cache defined by apps.
 	 */
-- 
2.17.0