Hi Chris,
On 04/20/2015 02:26 PM, Chris Wilson wrote:
> The intention of using video=<connector>:<mode: is primarily to select
> the user's preferred resolution at startup. Currently we always create a
> GTF mode irrespective of whether the monitor has a native mode at the
> desired resolution. This has the issue that we may then select the fake
> GTF mode rather the native mode during fb_helper->inital_config() and so
> on a non-GTF monitor we then end up with a loss of signal. Oops. This
> invalid fake mode would also be exported to userspace, who potentially
> may make the same mistake.
>
> To avoid this issue, we filter out the added command line mode if we
> detect the desired resolution (and clock if specified) amongst the
> probed modes. This fixes the immediate problem of adding a duplicate
> mode, but perhaps more generically we should avoid adding a GTF mode if
> the monitor has an EDID that is not GTF-compatible...
>
> A second issue sneaked into this patch is to add the cmdline mode mode
> ahead of the absolute fallback 1024x768 mode. That is if the user has
> specified a mode that we create as a fallback, we do not need to add a
> second unused fallback mode.
>
> Fixes regression from
>
> commit eaf99c749d43ae74ac7ffece5512f3c73f01dfd2
> Author: Chris Wilson <[email protected]>
> Date: Wed Aug 6 10:08:32 2014 +0200
>
> drm: Perform cmdline mode parsing during connector initialisation
>
> that breaks HDMI output on BeagleBone Black with LG TV (model 19LS4R-ZA).
>
> Reported-by: Radek Dostál <[email protected]>
> Signed-off-by: Chris Wilson <[email protected]>
> Cc: Radek Dostál <[email protected]>
> Cc: Jesse Barnes <[email protected]>
> Cc: Ville Syrjälä <[email protected]>
> Cc: Daniel Vetter <[email protected]>
> Cc: [email protected]
> Cc: Julia Lemire <[email protected]>
> Cc: Dave Airlie <[email protected]>
> Cc: [email protected]
NAKed-by: Radek Dostál <[email protected]>
sorry to let you know, but this patch does NOT work :( Attached is the
original.patch which you provided previously and it did work, but one of
the last minute changes had to break it :(
I hope you will find the issue soon,
Radek
diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
index 6350387..2168be0 100644
--- a/drivers/gpu/drm/drm_probe_helper.c
+++ b/drivers/gpu/drm/drm_probe_helper.c
@@ -79,13 +79,30 @@ drm_mode_validate_flag(const struct drm_display_mode *mode,
static int drm_helper_probe_add_cmdline_mode(struct drm_connector *connector)
{
+ struct drm_cmdline_mode *cmdline_mode;
struct drm_display_mode *mode;
- if (!connector->cmdline_mode.specified)
+ cmdline_mode = &connector->cmdline_mode;
+ if (!cmdline_mode->specified)
return 0;
+ /* Only add a GTF mode if we find no matching probed modes */
+ list_for_each_entry(mode, &connector->probed_modes, head) {
+ if (mode->hdisplay != cmdline_mode->xres ||
+ mode->vdisplay != cmdline_mode->yres)
+ continue;
+
+ if (cmdline_mode->refresh_specified) {
+ if (mode->vrefresh != cmdline_mode->refresh)
+ continue;
+ }
+
+ return 0;
+ }
+
+
mode = drm_mode_create_from_cmdline_mode(connector->dev,
- &connector->cmdline_mode);
+ cmdline_mode);
if (mode == NULL)
return 0;
@@ -195,7 +212,8 @@ static int drm_helper_probe_single_connector_modes_merge_bits(struct drm_connect
mode_flags |= DRM_MODE_FLAG_3D_MASK;
list_for_each_entry(mode, &connector->modes, head) {
- mode->status = drm_mode_validate_basic(mode);
+ if (mode->status == MODE_OK)
+ mode->status = drm_mode_validate_basic(mode);
if (mode->status == MODE_OK)
mode->status = drm_mode_validate_size(mode, maxX, maxY);
