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drm/nouveau/bios: fix a bit shift error introduced by 457e77b 

Commit 457e77b264 added two checks applied to a
value received from nv_rd32(bios, 0x619f04). But after this new piece of code
is executed, the addr local variable does not hold the same value it used to
hold before the commit. Here is what is was assigned in the original code:
	(u64)(nv_rd32(bios, 0x619f04) & 0xffffff00) << 8
in the committed code it ends up with this value:
	(u64)(nv_rd32(bios, 0x619f04) >> 8) << 8
These expressions are obviously not equivalent.

My Nvidia video card does not show anything on the display when I boot a
kernel containing this commit.

The patch fixes the code so that the new checks are still done, but the
side effect of an incorrect addr value is gone.

Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sergei Antonov <saproj@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
hifive-unleashed-5.1
Sergei Antonov 2014-04-15 23:18:37 +02:00 committed by Dave Airlie
parent d62c3e7a73
commit 9a11843987
1 changed files with 1 additions and 1 deletions
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2
drivers/gpu/drm/nouveau/core/subdev/bios/base.c
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@ -109,7 +109,7 @@ nouveau_bios_shadow_pramin(struct nouveau_bios *bios)
return;
}
addr = (u64)(addr >> 8) << 8;
addr = (addr & 0xffffff00) << 8;
if (!addr) {
addr = (u64)nv_rd32(bios, 0x001700) << 16;
addr += 0xf0000;