linux/debian/patches/bugfix/all/intel-agp-Clear-entire-GTT-...

60 lines
2.1 KiB
Diff

From fc61901373987ad61851ed001fe971f3ee8d96a3 Mon Sep 17 00:00:00 2001
From: David Woodhouse <dwmw2@infradead.org>
Date: Wed, 2 Dec 2009 11:00:05 +0000
Subject: [PATCH] agp/intel-agp: Clear entire GTT on startup
Some BIOSes fail to initialise the GTT, which will cause DMA faults when
the IOMMU is enabled. We need to clear the whole thing to point at the
scratch page, not just the part that Linux is going to use.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
[anholt: Note that this may also help with stability in the presence of
driver bugs, by not drawing to memory we don't own]
Signed-off-by: Eric Anholt <eric@anholt.net>
---
drivers/char/agp/intel-agp.c | 7 ++++++-
1 files changed, 6 insertions(+), 1 deletions(-)
diff --git a/drivers/char/agp/intel-agp.c b/drivers/char/agp/intel-agp.c
index 37cb4e2..33b4853 100644
--- a/drivers/char/agp/intel-agp.c
+++ b/drivers/char/agp/intel-agp.c
@@ -176,6 +176,7 @@ static struct _intel_private {
* popup and for the GTT.
*/
int gtt_entries; /* i830+ */
+ int gtt_total_size;
union {
void __iomem *i9xx_flush_page;
void *i8xx_flush_page;
@@ -1151,7 +1152,7 @@ static int intel_i915_configure(void)
readl(intel_private.registers+I810_PGETBL_CTL); /* PCI Posting. */
if (agp_bridge->driver->needs_scratch_page) {
- for (i = intel_private.gtt_entries; i < current_size->num_entries; i++) {
+ for (i = intel_private.gtt_entries; i < intel_private.gtt_total_size; i++) {
writel(agp_bridge->scratch_page, intel_private.gtt+i);
}
readl(intel_private.gtt+i-1); /* PCI Posting. */
@@ -1312,6 +1313,8 @@ static int intel_i915_create_gatt_table(struct agp_bridge_data *bridge)
if (!intel_private.gtt)
return -ENOMEM;
+ intel_private.gtt_total_size = gtt_map_size / 4;
+
temp &= 0xfff80000;
intel_private.registers = ioremap(temp, 128 * 4096);
@@ -1398,6 +1401,8 @@ static int intel_i965_create_gatt_table(struct agp_bridge_data *bridge)
if (!intel_private.gtt)
return -ENOMEM;
+ intel_private.gtt_total_size = gtt_size / 4;
+
intel_private.registers = ioremap(temp, 128 * 4096);
if (!intel_private.registers) {
iounmap(intel_private.gtt);
--
1.6.5.7