| Message ID | 1465838159-12940-1-git-send-email-mstaudt@suse.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 13/06/16 20:15, Max Staudt wrote: > When using efifb with a 16-bit (5:6:5) visual, fbcon's text is rendered > in the wrong colors - e.g. text gray (#aaaaaa) is rendered as green > (#50bc50) and neighboring pixels have slightly different values > (such as #50bc78). > > The reason is that fbcon loads its 16 color palette through > efifb_setcolreg(), which in turn calculates a 32-bit value to write > into memory for each palette index. > Until now, this code could only handle 8-bit visuals and didn't mask > overlapping values when ORing them. > > With this patch, fbcon displays the correct colors when a qemu VM is > booted in 16-bit mode (in GRUB: "set gfxpayload=800x600x16"). > > Fixes: 7c83172b98e5 ("x86_64 EFI boot support: EFI frame buffer driver") # v2.6.24+ > Signed-off-by: Max Staudt <mstaudt@suse.de> > Acked-By: Peter Jones <pjones@redhat.com> > Cc: stable@vger.kernel.org > --- > drivers/video/fbdev/efifb.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) Thanks, queued for v4.9. Tomi
diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c index 924bad4..37a37c4 100644 --- a/drivers/video/fbdev/efifb.c +++ b/drivers/video/fbdev/efifb.c @@ -50,9 +50,9 @@ static int efifb_setcolreg(unsigned regno, unsigned red, unsigned green, return 1; if (regno < 16) { - red >>= 8; - green >>= 8; - blue >>= 8; + red >>= 16 - info->var.red.length; + green >>= 16 - info->var.green.length; + blue >>= 16 - info->var.blue.length; ((u32 *)(info->pseudo_palette))[regno] = (red << info->var.red.offset) | (green << info->var.green.offset) |
When using efifb with a 16-bit (5:6:5) visual, fbcon's text is rendered in the wrong colors - e.g. text gray (#aaaaaa) is rendered as green (#50bc50) and neighboring pixels have slightly different values (such as #50bc78). The reason is that fbcon loads its 16 color palette through efifb_setcolreg(), which in turn calculates a 32-bit value to write into memory for each palette index. Until now, this code could only handle 8-bit visuals and didn't mask overlapping values when ORing them. With this patch, fbcon displays the correct colors when a qemu VM is booted in 16-bit mode (in GRUB: "set gfxpayload=800x600x16"). Fixes: 7c83172b98e5 ("x86_64 EFI boot support: EFI frame buffer driver") # v2.6.24+ Signed-off-by: Max Staudt <mstaudt@suse.de> Acked-By: Peter Jones <pjones@redhat.com> Cc: stable@vger.kernel.org --- drivers/video/fbdev/efifb.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)