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Diffstat (limited to 'arch/x86/include/asm/agp.h')
| -rw-r--r-- | arch/x86/include/asm/agp.h | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/arch/x86/include/asm/agp.h b/arch/x86/include/asm/agp.h new file mode 100644 index 000000000..62da760d6 --- /dev/null +++ b/arch/x86/include/asm/agp.h @@ -0,0 +1,32 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_X86_AGP_H +#define _ASM_X86_AGP_H + +#include <linux/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. + */ + +#define map_page_into_agp(page) set_pages_uc(page, 1) +#define unmap_page_from_agp(page) set_pages_wb(page, 1) + +/* + * 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() + +/* 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 /* _ASM_X86_AGP_H */ |