On Fri, 4 Jun 2021 at 16:49, Emil Velikov <emil.l.velikov@xxxxxxxxx> wrote: > > From: Emil Velikov <emil.velikov@xxxxxxxxxxxxx> > > Currently as the workaround is applied the screen flickers. As a result > we do not achieve seamless boot experience. > > Avoiding the issue in the common use-case might be hard, although we can > resolve it for dual GPU setups - when the "other" GPU is primary and/or > outputs are connected to it. > > With this I was able to get seamless experience on my Intel/Nvidia box, > running systemd-boot and sddm/Xorg. Note that the i915 driver is within > initrd while the Nvidia one is not. > > Without this patch, the splash presented by systemd-boot (UEFI BGRT) is > torn down as the code-path kicks in, leaving the monitor blank until the > login manager starts. > > Same issue were reported with plymouth/grub, although personally I > wasn't able to get them to behave on my setup. > > Suggested-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Signed-off-by: Emil Velikov <emil.velikov@xxxxxxxxxxxxx> > --- > > Supersedes > https://lore.kernel.org/dri-devel/20210516171432.1734268-1-emil.l.velikov@xxxxxxxxx/ > > Ville, others, > > Patch is based against drm-intel/drm-intel-next and will apply cleanly > against drm-intel/drm-intel-fixes. > > If possible, can one of the i915 maintainers apply it to the latter? > > Thanks > Emil > --- > drivers/gpu/drm/i915/display/intel_vga.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/gpu/drm/i915/display/intel_vga.c b/drivers/gpu/drm/i915/display/intel_vga.c > index be333699c515..7beef1206097 100644 > --- a/drivers/gpu/drm/i915/display/intel_vga.c > +++ b/drivers/gpu/drm/i915/display/intel_vga.c > @@ -29,6 +29,9 @@ void intel_vga_disable(struct drm_i915_private *dev_priv) > i915_reg_t vga_reg = intel_vga_cntrl_reg(dev_priv); > u8 sr1; > > + if (intel_de_read(dev_priv, vga_reg) & VGA_DISP_DISABLE) > + return; > + > /* WaEnableVGAAccessThroughIOPort:ctg,elk,ilk,snb,ivb,vlv,hsw */ > vga_get_uninterruptible(pdev, VGA_RSRC_LEGACY_IO); > outb(SR01, VGA_SR_INDEX); > -- > 2.31.1 > Humble poke? -Emil
