drm/nv50-nvc0: work around an evo channel hang that some people see

BugLink: http://bugs.launchpad.net/bugs/583760

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
(cherry picked from commit 59197c026257ab730c7fc8819a0e2b26e125a534)

Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Andy Whitcroft <andy.whitcroft@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

diff --git a/drivers/gpu/drm/nouveau/nv50_evo.c b/drivers/gpu/drm/nouveau/nv50_evo.c
index 0ea090f..3055dbe 100644 (file)
--- a/drivers/gpu/drm/nouveau/nv50_evo.c
+++ b/drivers/gpu/drm/nouveau/nv50_evo.c
@@ -182,6 +182,7 @@ nv50_evo_channel_init(struct nouveau_channel *evo)
        nv_mask(dev, 0x610028, 0x00000000, 0x00010001 << id);
 
        evo->dma.max = (4096/4) - 2;
+       evo->dma.max &= ~7;
        evo->dma.put = 0;
        evo->dma.cur = evo->dma.put;
        evo->dma.free = evo->dma.max - evo->dma.cur;