lkml.org 
[lkml]   [2020]   [Jan]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.19 218/639] drm/nouveau/bios/ramcfg: fix missing parentheses when calculating RON
    Date
    From: Colin Ian King <colin.king@canonical.com>

    [ Upstream commit 13649101a25c53c87f4ab98a076dfe61f3636ab1 ]

    Currently, the expression for calculating RON is always going to result
    in zero no matter the value of ram->mr[1] because the ! operator has
    higher precedence than the shift >> operator. I believe the missing
    parentheses around the expression before appying the ! operator will
    result in the desired result.

    [ Note, not tested ]

    Detected by CoveritScan, CID#1324005 ("Operands don't affect result")

    Fixes: c25bf7b6155c ("drm/nouveau/bios/ramcfg: Separate out RON pull value")
    Signed-off-by: Colin Ian King <colin.king@canonical.com>
    Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
    Signed-off-by: Sasha Levin <sashal@kernel.org>
    ---
    drivers/gpu/drm/nouveau/nvkm/subdev/fb/gddr3.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/fb/gddr3.c b/drivers/gpu/drm/nouveau/nvkm/subdev/fb/gddr3.c
    index 60ece0a8a2e1b..1d2d6bae73cd1 100644
    --- a/drivers/gpu/drm/nouveau/nvkm/subdev/fb/gddr3.c
    +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/fb/gddr3.c
    @@ -87,7 +87,7 @@ nvkm_gddr3_calc(struct nvkm_ram *ram)
    WR = (ram->next->bios.timing[2] & 0x007f0000) >> 16;
    /* XXX: Get these values from the VBIOS instead */
    DLL = !(ram->mr[1] & 0x1);
    - RON = !(ram->mr[1] & 0x300) >> 8;
    + RON = !((ram->mr[1] & 0x300) >> 8);
    break;
    default:
    return -ENOSYS;
    --
    2.20.1


    \
     
     \ /
      Last update: 2020-01-24 12:43    [W:3.133 / U:0.700 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site