OpenCloudOS-Kernel/include/asm-x86/agp.h

41 lines
1.3 KiB
C

#ifndef _ASM_X86_AGP_H
#define _ASM_X86_AGP_H
#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