Skip to content

drm/connector: hdmi: Prefer YUV422 over dropping RGB to 8 bpc #7682

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Draft
popcornmix wants to merge 1 commit into
base: rpi-6.18.y
Choose a base branch
from
+14 −5
Draft

drm/connector: hdmi: Prefer YUV422 over dropping RGB to 8 bpc #7682

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
19 changes: 14 additions & 5 deletions drivers/gpu/drm/display/drm_hdmi_state_helper.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -611,13 +611,14 @@ static int
hdmi_compute_format_bpc(const struct drm_connector *connector,
struct drm_connector_state *conn_state,
const struct drm_display_mode *mode,
unsigned int max_bpc, enum hdmi_colorspace fmt)
unsigned int max_bpc, unsigned int min_bpc,
enum hdmi_colorspace fmt)
{
struct drm_device *dev = connector->dev;
unsigned int bpc;
int ret;

for (bpc = max_bpc; bpc >= 8; bpc -= 2) {
for (bpc = max_bpc; bpc >= min_bpc; bpc -= 2) {
ret = hdmi_try_format_bpc(connector, conn_state, mode, bpc, fmt);
if (!ret)
continue;
Expand Down Expand Up @@ -651,17 +652,25 @@ hdmi_compute_config(const struct drm_connector *connector,
8, connector->max_bpc);
int ret;

/*
* If more than 8 bpc was requested, YUV422 at 12 bpc needs the same
* TMDS rate as RGB at 8 bpc, so try it before dropping RGB to 8 bpc.
*/
ret = hdmi_compute_format_bpc(connector, conn_state, mode, max_bpc,
HDMI_COLORSPACE_RGB);
min(max_bpc, 10), HDMI_COLORSPACE_RGB);

if (ret)
ret = hdmi_compute_format_bpc(connector, conn_state, mode,
max_bpc, HDMI_COLORSPACE_YUV422);
max_bpc, 8, HDMI_COLORSPACE_YUV422);

if (ret && max_bpc > 8)
ret = hdmi_compute_format_bpc(connector, conn_state, mode,
8, 8, HDMI_COLORSPACE_RGB);

if (ret) {
if (connector->ycbcr_420_allowed) {
ret = hdmi_compute_format_bpc(connector, conn_state,
mode, max_bpc,
mode, max_bpc, 8,
HDMI_COLORSPACE_YUV420);
if (ret)
drm_dbg_kms(connector->dev,
Expand Down
Loading