x86, gart: Set DISTLBWALKPRB bit always
The DISTLBWALKPRB bit must be set for the GART because the
gatt table is mapped UC. But the current code does not set
the bit at boot when the BIOS setup the aperture correctly.
Fix that by setting this bit when enabling the GART instead
of the other places.
Cc: <stable@kernel.org>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Link: http://lkml.kernel.org/r/1303134346-5805-4-git-send-email-joerg.roedel@amd.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/x86/include/asm/gart.h b/arch/x86/include/asm/gart.h
index 88c1ebe..156cd5d 100644
--- a/arch/x86/include/asm/gart.h
+++ b/arch/x86/include/asm/gart.h
@@ -66,7 +66,7 @@
* Don't enable translation but enable GART IO and CPU accesses.
* Also, set DISTLBWALKPRB since GART tables memory is UC.
*/
- ctl = DISTLBWALKPRB | order << 1;
+ ctl = order << 1;
pci_write_config_dword(dev, AMD64_GARTAPERTURECTL, ctl);
}
@@ -83,7 +83,7 @@
/* Enable GART translation for this hammer. */
pci_read_config_dword(dev, AMD64_GARTAPERTURECTL, &ctl);
- ctl |= GARTEN;
+ ctl |= GARTEN | DISTLBWALKPRB;
ctl &= ~(DISGARTCPU | DISGARTIO);
pci_write_config_dword(dev, AMD64_GARTAPERTURECTL, ctl);
}
diff --git a/arch/x86/kernel/aperture_64.c b/arch/x86/kernel/aperture_64.c
index 86d1ad4..73fb469 100644
--- a/arch/x86/kernel/aperture_64.c
+++ b/arch/x86/kernel/aperture_64.c
@@ -499,7 +499,7 @@
* Don't enable translation yet but enable GART IO and CPU
* accesses and set DISTLBWALKPRB since GART table memory is UC.
*/
- u32 ctl = DISTLBWALKPRB | aper_order << 1;
+ u32 ctl = aper_order << 1;
bus = amd_nb_bus_dev_ranges[i].bus;
dev_base = amd_nb_bus_dev_ranges[i].dev_base;