From: Max Staudt Date: Mon, 13 Jun 2016 17:15:59 +0000 (+0200) Subject: fbdev/efifb: Fix 16 color palette entry calculation X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=16654a56f02b36e9377d991853227f598d3bdbf6;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git fbdev/efifb: Fix 16 color palette entry calculation commit d50b3f43db739f03fcf8c0a00664b3d2fed0496e upstream. 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 Acked-By: Peter Jones Signed-off-by: Tomi Valkeinen Signed-off-by: Willy Tarreau --- diff --git a/drivers/video/efifb.c b/drivers/video/efifb.c index 50fe668c6172..08dbe8ae0212 100644 --- a/drivers/video/efifb.c +++ b/drivers/video/efifb.c @@ -270,9 +270,9 @@ 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) |