radv: fix sample shading on GFX 10.3

Based on RadeonSI.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6168>

diff --git a/src/amd/vulkan/si_cmd_buffer.c b/src/amd/vulkan/si_cmd_buffer.c
index 766d73fc08ad9839cb59165b72096cab96802860..1015730507ab08541e119d198d6188d2bcf71841 100644 (file)
--- a/src/amd/vulkan/si_cmd_buffer.c
+++ b/src/amd/vulkan/si_cmd_buffer.c
@@ -420,6 +420,7 @@ si_emit_graphics(struct radv_device *device,
 
                if (physical_device->rad_info.chip_class >= GFX10_3) {
                        radeon_set_context_reg(cs, R_028750_SX_PS_DOWNCONVERT_CONTROL_GFX103, 0xff);
+                       radeon_set_context_reg(cs, 0x28848, 1 << 9); /* This fixes sample shading. */
                }
 
                if (physical_device->rad_info.chip_class == GFX10) {