niri-config: add keep-max-bpc-unchanged option (#2195)

* niri-config: add disable-set-bpc option
setting bpc to 8 bricks some OLED displays driven by amdgpu

* change to keep-max-bpc-unchanged and add to wiki

* fmt

* Update wiki/Configuration:-Debug-Options.md

---------

Co-authored-by: Ivan Molodetskikh <yalterz@gmail.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/wiki/Configuration:-Debug-Options.md b/wiki/Configuration:-Debug-Options.md
index ad74dba7..f2d38de0 100644
--- a/wiki/Configuration:-Debug-Options.md
+++ b/wiki/Configuration:-Debug-Options.md
@@ -30,6 +30,7 @@ debug {
     honor-xdg-activation-with-invalid-serial
     skip-cursor-only-updates-during-vrr
     deactivate-unfocused-windows
+    keep-max-bpc-unchanged
 }
 
 binds {
@@ -292,6 +293,23 @@ debug {
 }
 ```
 
+### `keep-max-bpc-unchanged`
+
+<sup>Since: next release</sup>
+
+When connecting monitors, niri sets their max bpc to 8 in order to reduce display bandwidth and to potentially allow more monitors to be connected at once.
+Restricting bpc to 8 is not a problem since we don't support HDR or color management yet and can't really make use of higher bpc.
+
+Apparently, setting max bpc to 8 breaks some displays driven by AMDGPU.
+If this happens to you, set this debug flag, which will prevent niri from changing max bpc.
+AMDGPU bug report: https://gitlab.freedesktop.org/drm/amd/-/issues/4487.
+
+```kdl
+debug {
+    keep-max-bpc-unchanged
+}
+```
+
 ### Key Bindings
 
 These are not debug options, but rather key bindings.