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Diffstat (limited to '')
| -rw-r--r-- | arch/x86/include/asm/agp.h | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/x86/include/asm/agp.h b/arch/x86/include/asm/agp.h new file mode 100644 index 0000000000..c8c111d8fb --- /dev/null +++ b/arch/x86/include/asm/agp.h @@ -0,0 +1,26 @@ +/* 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 cacheability 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() + +#endif /* _ASM_X86_AGP_H */ |