include/asm-x86/agp.h

   1 #ifndef _ASM_X86_AGP_H
   2 #define _ASM_X86_AGP_H
   3
   4 #include <asm/pgtable.h>
   5 #include <asm/cacheflush.h>
   6
   7 /*
   8  * Functions to keep the agpgart mappings coherent with the MMU. The
   9  * GART gives the CPU a physical alias of pages in memory. The alias
  10  * region is mapped uncacheable. Make sure there are no conflicting
  11  * mappings with different cachability attributes for the same
  12  * page. This avoids data corruption on some CPUs.
  13  */
  14
  15 /*
  16  * Caller's responsibility to call global_flush_tlb() for performance
  17  * reasons
  18  */
  19 #define map_page_into_agp(page) change_page_attr(page, 1, PAGE_KERNEL_NOCACHE)
  20 #define unmap_page_from_agp(page) change_page_attr(page, 1, PAGE_KERNEL)
  21 #define flush_agp_mappings() global_flush_tlb()
  22
  23 /*
  24  * Could use CLFLUSH here if the cpu supports it. But then it would
  25  * need to be called for each cacheline of the whole page so it may
  26  * not be worth it. Would need a page for it.
  27  */
  28 #define flush_agp_cache() wbinvd()
  29
  30 /* Convert a physical address to an address suitable for the GART. */
  31 #define phys_to_gart(x) (x)
  32 #define gart_to_phys(x) (x)
  33
  34 /* GATT allocation. Returns/accepts GATT kernel virtual address. */
  35 #define alloc_gatt_pages(order)         \
  36         ((char *)__get_free_pages(GFP_KERNEL, (order)))
  37 #define free_gatt_pages(table, order)   \
  38         free_pages((unsigned long)(table), (order))
  39
  40 #endif