diff options
| author | Arjan van dev Ven <arjan@linux.intel.com> | 2008-02-06 07:16:00 +0300 |
|---|---|---|
| committer | Dave Airlie <airlied@linux.ie> | 2008-02-19 07:46:39 +0300 |
| commit | fcea424d31868a78366ad5ee0cb3cc2a4cbe689b (patch) | |
| tree | 9b3a2be661c07d8b094a5489ecafffe4befe5ec0 /drivers/char/agp/generic.c | |
| parent | 16469a0ea0f6b7562eac98ebb8a7c41ce902d0b1 (diff) | |
| download | linux-fcea424d31868a78366ad5ee0cb3cc2a4cbe689b.tar.xz | |
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/generic.c')
| -rw-r--r-- | drivers/char/agp/generic.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/char/agp/generic.c b/drivers/char/agp/generic.c index 7484bc759c4c..7fc0c99a3a58 100644 --- a/drivers/char/agp/generic.c +++ b/drivers/char/agp/generic.c @@ -932,9 +932,14 @@ int agp_generic_create_gatt_table(struct agp_bridge_data *bridge) agp_gatt_table = (void *)table; bridge->driver->cache_flush(); +#ifdef CONFIG_X86 + set_memory_uc((unsigned long)table, 1 << page_order); + bridge->gatt_table = (void *)table; +#else bridge->gatt_table = ioremap_nocache(virt_to_gart(table), (PAGE_SIZE * (1 << page_order))); bridge->driver->cache_flush(); +#endif if (bridge->gatt_table == NULL) { for (page = virt_to_page(table); page <= virt_to_page(table_end); page++) @@ -991,7 +996,11 @@ int agp_generic_free_gatt_table(struct agp_bridge_data *bridge) * called, then all agp memory is deallocated and removed * from the table. */ +#ifdef CONFIG_X86 + set_memory_wb((unsigned long)bridge->gatt_table, 1 << page_order); +#else iounmap(bridge->gatt_table); +#endif table = (char *) bridge->gatt_table_real; table_end = table + ((PAGE_SIZE * (1 << page_order)) - 1); |