Bug 215355

Summary: black screen and show "the current input timing is not supported by the monitor display"
Product: Drivers Reporter: Z. Liu (zhixu.liu)
Component: Console/FramebuffersAssignee: James Simmons (jsimmons)
Status: NEW ---    
Severity: blocking    
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: since v5.6-rc2 Subsystem:
Regression: No Bisected commit-id:
Attachments: [patch] fix black screen on some monitor

Description Z. Liu 2021-12-18 08:27:40 UTC
after updated kernel to 5.10, monitor become black w/ error message said:
"The current input timing is not supported by the monitor display. Please change your input timing to 1920x1080@60Hz ...", so I did a git bisect, and the result is:

# first bad commit: [11be60bd66d5431018d706ec623c8ece80a7f931] matroxfb: add Matrox MGA-G200eW board support

Display become normal after apply following patch:

diff --git a/drivers/video/fbdev/matrox/matroxfb_base.c b/drivers/video/fbdev/matrox/matroxfb_base.c
index 5c82611e93d9..236521b19daf 100644
--- a/drivers/video/fbdev/matrox/matroxfb_base.c
+++ b/drivers/video/fbdev/matrox/matroxfb_base.c
@@ -1377,7 +1377,7 @@ static struct video_board vbG200 = {
        .lowlevel = &matrox_G100
 };
 static struct video_board vbG200eW = {
-       .maxvram = 0x800000,
+       .maxvram = 0x100000,
        .maxdisplayable = 0x800000,
        .accelID = FB_ACCEL_MATROX_MGAG200,
        .lowlevel = &matrox_G100

I don't really know the meaning of the value I changed, just use this value from 
 vbG200 for a test.
Comment 1 Z. Liu 2021-12-18 08:41:10 UTC
Created attachment 300061 [details]
[patch] fix black screen on some monitor

Monitor become black w/ error message said: "The current input timing is not supported by the monitor display. Please change your input timing to 1920x1080@60Hz ...".

Display show normaly after apply the patch.