On Wed, 2019-04-03 at 09:23 +0200, Gerd Hoffmann wrote: > - Only DRM_FORMAT_RGB565 (depth 16) is supported. The old driver does > that too by default. There was a module parameter which enables 24/32 > bpp support and disables higher resolutions (due to cirrus hardware > constrains). That parameter wasn't reimplemented.
One slightly annoying aspect of this (well, initially of the patch to clamp the default to 16bpp, but this too) is that we only have a way to ask the driver which format it prefers, not which ones it supports at all. For X's modesetting driver (and yes some of this is because X is awful) this creates the following failure mode: 1: user sets up xorg.conf for depth 24 2: user upgrades kernel, reboots 3: X driver detects that depth 16 is preferred, but 4: X core respects user's xorg.conf and tries depth 24, which 5: throws -EINVAL and X won't start. Possibly X should work around this by transparently setting up a shadow framebuffer at the user's requested depth. The problem there is, if 565 is preferred but 8888 works, you're adding a format-conversion blit in the middle for no reason. If I could ask the kernel for the entire list of supported formats, I could only set up the shadow if it was necessary. - ajax _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
