fdo-mirrors/mesa
1
0
Fork 0
mirror of https://gitlab.freedesktop.org/mesa/mesa.git synced 2025-12-24 19:40:10 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

v3dv: do not emit full tile buffers clears to handle Z/S clears

Browse source 
There was a misunderstanding regarding the scope of some hardware bugs
that led us to think that:

1. The Clear Tile Buffer Z/S bit was broken
2. The Clear Tile Buffer RTs bit would also clear Z/S.

1) is not really true, what happened was that some other bugs for which
we need workarounds anyway would have that effect. 2) was only true
for V3D 4.1, so it doesn't affect v3dv.

This change makes proper use of the Z/S bit instead of falling back to
clearing all tile buffers every time we have a Z/S clear. This also
allows us to do color clears on the tile store (which is faster) rather
than falling back to the clear all RTs bit every time we have a Z/S clear.

v2: rewrite the original comment about the hardwarebug description to
    include recent discussions with Broadcom instead of keeping it as
    is and amending it with an update note.

Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8589>
This commit is contained in:
Iago Toral Quiroga 2021-01-20 09:51:33 +01:00
parent 3c19a518c9
commit f989d4ce1c
1 changed files with 23 additions and 15 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

38
src/broadcom/vulkan/v3dv_cmd_buffer.c
View file

@ -1739,7 +1739,8 @@ cmd_buffer_render_pass_emit_stores(struct v3dv_cmd_buffer *cmd_buffer,
&state->pass->subpasses[state->subpass_idx];
bool has_stores = false;
bool use_global_clear = false;
bool use_global_zs_clear = false;
bool use_global_rt_clear = false;
/* FIXME: separate stencil */
uint32_t ds_attachment_idx = subpass->ds_attachment.attachment;
@ -1793,19 +1794,26 @@ cmd_buffer_render_pass_emit_stores(struct v3dv_cmd_buffer *cmd_buffer,
ds_attachment->desc.stencilStoreOp);
/* GFXH-1689: The per-buffer store command's clear buffer bit is broken
* for depth/stencil. In addition, the clear packet's Z/S bit is broken,
* but the RTs bit ends up clearing Z/S.
* for depth/stencil.
*
* There used to be some confusion regarding the Clear Tile Buffers
* Z/S bit also being broken, but we confirmed with Broadcom that this
* is not the case, it was just that some other hardware bugs (that we
* need to work around, such as GFXH-1461) could cause this bit to behave
* incorrectly.
*
* There used to be another issue where the RTs bit in the Clear Tile
* Buffers packet also cleared Z/S, but Broadcom confirmed this is
* fixed since V3D 4.1.
*
* So if we have to emit a clear of depth or stencil we don't use
* per-buffer clears, not even for color, since we will have to emit
* a clear command for all tile buffers (including color) to handle
* the depth/stencil clears.
* the per-buffer store clear bit, even if we need to store the buffers,
* instead we always have to use the Clear Tile Buffers Z/S bit.
*
* Note that this bug is not reproduced in the simulator, where
* using the clear buffer bit in depth/stencil stores seems to work
* correctly.
* Note that GFXH-1689 is not reproduced in the simulator, where
* using the clear buffer bit in depth/stencil stores works fine.
*/
use_global_clear = needs_depth_clear || needs_stencil_clear;
use_global_zs_clear = needs_depth_clear || needs_stencil_clear;
if (needs_depth_store || needs_stencil_store) {
const uint32_t zs_buffer =
v3dv_zs_buffer(needs_depth_store, needs_stencil_store);
@ -1875,11 +1883,11 @@ cmd_buffer_render_pass_emit_stores(struct v3dv_cmd_buffer *cmd_buffer,
cmd_buffer_render_pass_emit_store(cmd_buffer, cl,
attachment_idx, layer,
RENDER_TARGET_0 + i,
needs_clear && !use_global_clear,
needs_clear && !use_global_rt_clear,
false);
has_stores = true;
} else if (needs_clear) {
use_global_clear = true;
use_global_rt_clear = true;
}
}
@ -1893,10 +1901,10 @@ cmd_buffer_render_pass_emit_stores(struct v3dv_cmd_buffer *cmd_buffer,
/* If we have any depth/stencil clears we can't use the per-buffer clear
* bit and instead we have to emit a single clear of all tile buffers.
*/
if (use_global_clear) {
if (use_global_zs_clear || use_global_rt_clear) {
cl_emit(cl, CLEAR_TILE_BUFFERS, clear) {
clear.clear_z_stencil_buffer = true;
clear.clear_all_render_targets = true;
clear.clear_z_stencil_buffer = use_global_zs_clear;
clear.clear_all_render_targets = use_global_rt_clear;
}
}
}