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Diffstat (limited to 'include/asm-x86/agp_32.h')
| -rw-r--r-- | include/asm-x86/agp_32.h | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/include/asm-x86/agp_32.h b/include/asm-x86/agp_32.h new file mode 100644 index 000000000000..6af173dbf123 --- /dev/null +++ b/include/asm-x86/agp_32.h @@ -0,0 +1,36 @@ +#ifndef AGP_H +#define AGP_H 1 + +#include <asm/pgtable.h> +#include <asm/cacheflush.h> + +/* + * Functions to keep the agpgart mappings coherent with the MMU. + * The GART gives the CPU a physical alias of pages in memory. The alias region is + * mapped uncacheable. Make sure there are no conflicting mappings + * with different cachability attributes for the same page. This avoids + * data corruption on some CPUs. + */ + +/* Caller's responsibility to call global_flush_tlb() for + * performance reasons */ +#define map_page_into_agp(page) change_page_attr(page, 1, PAGE_KERNEL_NOCACHE) +#define unmap_page_from_agp(page) change_page_attr(page, 1, PAGE_KERNEL) +#define flush_agp_mappings() global_flush_tlb() + +/* Could use CLFLUSH here if the cpu supports it. But then it would + need to be called for each cacheline of the whole page so it may not be + worth it. Would need a page for it. */ +#define flush_agp_cache() wbinvd() + +/* Convert a physical address to an address suitable for the GART. */ +#define phys_to_gart(x) (x) +#define gart_to_phys(x) (x) + +/* GATT allocation. Returns/accepts GATT kernel virtual address. */ +#define alloc_gatt_pages(order) \ + ((char *)__get_free_pages(GFP_KERNEL, (order))) +#define free_gatt_pages(table, order) \ + free_pages((unsigned long)(table), (order)) + +#endif |