radv: Use a lower max offchip buffer count.

No clue what gets fixed by this but both radeonsi and amdvlk do it.

CC: <mesa-stable@lists.freedesktop.org>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>

diff --git a/src/amd/vulkan/radv_device.c b/src/amd/vulkan/radv_device.c
index c300c88..53f99a8 100644 (file)
--- a/src/amd/vulkan/radv_device.c
+++ b/src/amd/vulkan/radv_device.c
@@ -1901,10 +1901,30 @@ radv_get_hs_offchip_param(struct radv_device *device, uint32_t *max_offchip_buff
                device->physical_device->rad_info.family != CHIP_CARRIZO &&
                device->physical_device->rad_info.family != CHIP_STONEY;
        unsigned max_offchip_buffers_per_se = double_offchip_buffers ? 128 : 64;
-       unsigned max_offchip_buffers = max_offchip_buffers_per_se *
-               device->physical_device->rad_info.max_se;
+       unsigned max_offchip_buffers;
        unsigned offchip_granularity;
        unsigned hs_offchip_param;
+
+       /*
+        * Per RadeonSI:
+        * This must be one less than the maximum number due to a hw limitation.
+         * Various hardware bugs in SI, CIK, and GFX9 need this.
+        *
+        * Per AMDVLK:
+        * Vega10 should limit max_offchip_buffers to 508 (4 * 127).
+        * Gfx7 should limit max_offchip_buffers to 508
+        * Gfx6 should limit max_offchip_buffers to 126 (2 * 63)
+        *
+        * Follow AMDVLK here.
+        */
+       if (device->physical_device->rad_info.family == CHIP_VEGA10 ||
+           device->physical_device->rad_info.chip_class == CIK ||
+           device->physical_device->rad_info.chip_class == SI)
+               --max_offchip_buffers_per_se;
+
+       max_offchip_buffers = max_offchip_buffers_per_se *
+               device->physical_device->rad_info.max_se;
+
        switch (device->tess_offchip_block_dw_size) {
        default:
                assert(0);