summaryrefslogtreecommitdiffstats
path: root/drivers/char/agp/amd-k7-agp.c
diff options
context:
space:
mode:
authorArjan van dev Ven <arjan@linux.intel.com>2008-02-06 05:16:00 +0100
committerDave Airlie <airlied@linux.ie>2008-02-19 14:46:39 +1000
commitfcea424d31868a78366ad5ee0cb3cc2a4cbe689b (patch)
tree9b3a2be661c07d8b094a5489ecafffe4befe5ec0 /drivers/char/agp/amd-k7-agp.c
parent16469a0ea0f6b7562eac98ebb8a7c41ce902d0b1 (diff)
downloadop-kernel-dev-fcea424d31868a78366ad5ee0cb3cc2a4cbe689b.zip
op-kernel-dev-fcea424d31868a78366ad5ee0cb3cc2a4cbe689b.tar.gz
fix historic ioremap() abuse in AGP
Several AGP drivers right now use ioremap_nocache() on kernel ram in order to turn a page of regular memory uncached. There are two problems with this: 1) This is a total nightmare for the ioremap() implementation to keep various mappings of the same page coherent. 2) It's a total nightmare for the AGP code since it adds a ton of complexity in terms of keeping track of 2 different pointers to the same thing, in terms of error handling etc etc. This patch fixes this by making the AGP drivers use the new set_memory_XX APIs instead. Note: amd-k7-agp.c is built on Alpha too, and generic.c is built on ia64 as well, which do not yet have the set_memory_*() APIs, so for them some we have a few ugly #ifdefs - hopefully they'll be fixed soon. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Dave Airlie <airlied@linux.ie>
Diffstat (limited to 'drivers/char/agp/amd-k7-agp.c')
-rw-r--r--drivers/char/agp/amd-k7-agp.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/char/agp/amd-k7-agp.c b/drivers/char/agp/amd-k7-agp.c
index 87be464..fca4d7f 100644
--- a/drivers/char/agp/amd-k7-agp.c
+++ b/drivers/char/agp/amd-k7-agp.c
@@ -41,6 +41,7 @@ static int amd_create_page_map(struct amd_page_map *page_map)
if (page_map->real == NULL)
return -ENOMEM;
+#ifndef CONFIG_X86
SetPageReserved(virt_to_page(page_map->real));
global_cache_flush();
page_map->remapped = ioremap_nocache(virt_to_gart(page_map->real),
@@ -52,6 +53,10 @@ static int amd_create_page_map(struct amd_page_map *page_map)
return -ENOMEM;
}
global_cache_flush();
+#else
+ set_memory_uc(page_map->real, 1);
+ page_map->remapped = page_map->real;
+#endif
for (i = 0; i < PAGE_SIZE / sizeof(unsigned long); i++) {
writel(agp_bridge->scratch_page, page_map->remapped+i);
@@ -63,8 +68,12 @@ static int amd_create_page_map(struct amd_page_map *page_map)
static void amd_free_page_map(struct amd_page_map *page_map)
{
+#ifndef CONFIG_X86
iounmap(page_map->remapped);
ClearPageReserved(virt_to_page(page_map->real));
+#else
+ set_memory_wb(page_map->real, 1);
+#endif
free_page((unsigned long) page_map->real);
}
OpenPOWER on IntegriCloud