summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/gma500/mid_bios.c
diff options
context:
space:
mode:
authorAlan Cox <alan@linux.intel.com>2011-11-29 22:27:45 +0000
committerDave Airlie <airlied@redhat.com>2011-12-06 09:55:41 +0000
commitaa0c45fdca0cff3d1ba06578a84c9bc7f29a0960 (patch)
treeed2b380de5668f7b7d8ee87b8433ef2082924ef4 /drivers/gpu/drm/gma500/mid_bios.c
parent1b223c9ebf11e9597820fac57b211709f8ffce26 (diff)
gma500: Fix oaktrail probing part 1
The Oaktrail platform does not use the GCT/VBT format that is used by the Moorestowm (non PC legacy) equivalent device. It uses the BIOS tables which means an opregion and the like. The current code uses the wrong table which breaks things like the Fujitsu q550 tablets. Fix the table usage as a first step. The problem was found and diagnosed by Chia-I Wu Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'drivers/gpu/drm/gma500/mid_bios.c')
-rw-r--r--drivers/gpu/drm/gma500/mid_bios.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/gpu/drm/gma500/mid_bios.c b/drivers/gpu/drm/gma500/mid_bios.c
index 018ab469772e..128e6bb37568 100644
--- a/drivers/gpu/drm/gma500/mid_bios.c
+++ b/drivers/gpu/drm/gma500/mid_bios.c
@@ -142,6 +142,12 @@ static void mid_get_vbt_data(struct drm_psb_private *dev_priv)
memcpy(vbt, vbt_virtual, sizeof(*vbt));
iounmap(vbt_virtual); /* Free virtual address space */
+ /* No matching signature don't process the data */
+ if (memcmp(vbt->signature, "$GCT", 4)) {
+ vbt->size = 0;
+ return;
+ }
+
dev_dbg(dev->dev, "GCT revision is %x\n", vbt->revision);
switch (vbt->revision) {