From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Jones Date: Tue, 07 Jun 2016 17:23:05 +0000 Subject: Re: [PATCH] [efifb] Fix 16 color palette entry calculation Message-Id: <20160607172304.GD24886@redhat.com> List-Id: References: <1465307143-21398-1-git-send-email-mstaudt@suse.de> In-Reply-To: <1465307143-21398-1-git-send-email-mstaudt@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: quoted-printable To: Max Staudt Cc: plagnioj@jcrosoft.com, tomi.valkeinen@ti.com, eich@suse.de, tiwai@suse.de, agraf@suse.de, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, Matt Fleming On Tue, Jun 07, 2016 at 03:45:43PM +0200, 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). >=20 > 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. >=20 > With this patch, fbcon displays the correct colors when a qemu VM is > booted in 16-bit mode (in GRUB: "set gfxpayload=800x600x16"). >=20 > Signed-off-by: Max Staudt > --- > drivers/video/fbdev/efifb.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) >=20 > 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; > =20 > if (regno < 16) { > - red >>=3D 8; > - green >>=3D 8; > - blue >>=3D 8; > + red >>=3D 16 - info->var.red.length; > + green >>=3D 16 - info->var.green.length; > + blue >>=3D 16 - info->var.blue.length; > ((u32 *)(info->pseudo_palette))[regno] > (red << info->var.red.o= ffset) | > (green << info->var.green.offset) | > --=20 > 2.6.6 Looks right to me. Acked-By: Peter Jones --=20 Peter