agp.h 1.0 KB

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  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. #ifndef _ASM_X86_AGP_H
  3. #define _ASM_X86_AGP_H
  4. #include <linux/pgtable.h>
  5. #include <asm/cacheflush.h>
  6. /*
  7. * Functions to keep the agpgart mappings coherent with the MMU. The
  8. * GART gives the CPU a physical alias of pages in memory. The alias
  9. * region is mapped uncacheable. Make sure there are no conflicting
  10. * mappings with different cacheability attributes for the same
  11. * page. This avoids data corruption on some CPUs.
  12. */
  13. #define map_page_into_agp(page) set_pages_uc(page, 1)
  14. #define unmap_page_from_agp(page) set_pages_wb(page, 1)
  15. /*
  16. * Could use CLFLUSH here if the cpu supports it. But then it would
  17. * need to be called for each cacheline of the whole page so it may
  18. * not be worth it. Would need a page for it.
  19. */
  20. #define flush_agp_cache() wbinvd()
  21. /* GATT allocation. Returns/accepts GATT kernel virtual address. */
  22. #define alloc_gatt_pages(order) \
  23. ((char *)__get_free_pages(GFP_KERNEL, (order)))
  24. #define free_gatt_pages(table, order) \
  25. free_pages((unsigned long)(table), (order))
  26. #endif /* _ASM_X86_AGP_H */