On 15/09/2022 17:03, Thomas Zimmermann wrote:
G200ER does not seem to support 24 bpp, so force the console to
use 32 bpp. The problem was introduced, when commit 73f54d5d9682
("drm/mgag200: Remove special case for G200SE with <2 MiB") changed
the preferred color depth from 32 bit to 24 bit.
A setting of 24 is the correct color depth, but G200ER doesn't seem
to be able to use the respective RGB888 color format. Using 24-bit
color with forced 32 bpp works around the problem.
Thanks for the patch.
At least on my G200EW, 24 bpp is working well. So maybe only the G200ER
is affected.
I think it may have a performance penalty, I will try to measure it.
Reviewed-by: Jocelyn Falempe <jfalempe@xxxxxxxxxx>
--
Jocelyn
Reported-by: Wang Yugui <wangyugui@xxxxxxxxxxxx>
Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
Tested-by: Wang Yugui <wangyugui@xxxxxxxxxxxx>
Fixes: 73f54d5d9682 ("drm/mgag200: Remove special case for G200SE with <2 MiB")
Cc: Thomas Zimmermann <tzimmermann@xxxxxxx>
Cc: Jocelyn Falempe <jfalempe@xxxxxxxxxx>
Cc: Dave Airlie <airlied@xxxxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
---
drivers/gpu/drm/mgag200/mgag200_drv.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/mgag200/mgag200_drv.c b/drivers/gpu/drm/mgag200/mgag200_drv.c
index 251a1bb648cc..a222bf76804f 100644
--- a/drivers/gpu/drm/mgag200/mgag200_drv.c
+++ b/drivers/gpu/drm/mgag200/mgag200_drv.c
@@ -262,7 +262,11 @@ mgag200_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
if (ret)
return ret;
- drm_fbdev_generic_setup(dev, 0);
+ /*
+ * FIXME: A 24-bit color depth does not work with 24 bpp on
+ * G200ER. Force 32 bpp.
+ */
+ drm_fbdev_generic_setup(dev, 32);
return 0;
}
