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Diffstat (limited to 'arch/score/include/asm/fixmap.h')
-rw-r--r-- | arch/score/include/asm/fixmap.h | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/arch/score/include/asm/fixmap.h b/arch/score/include/asm/fixmap.h new file mode 100644 index 00000000000..ee167669402 --- /dev/null +++ b/arch/score/include/asm/fixmap.h @@ -0,0 +1,82 @@ +#ifndef _ASM_SCORE_FIXMAP_H +#define _ASM_SCORE_FIXMAP_H + +#include <asm/page.h> + +#define PHY_RAM_BASE 0x00000000 +#define PHY_IO_BASE 0x10000000 + +#define VIRTUAL_RAM_BASE 0xa0000000 +#define VIRTUAL_IO_BASE 0xb0000000 + +#define RAM_SPACE_SIZE 0x10000000 +#define IO_SPACE_SIZE 0x10000000 + +/* Kernel unmapped, cached 512MB */ +#define KSEG1 0xa0000000 + +/* + * Here we define all the compile-time 'special' virtual + * addresses. The point is to have a constant address at + * compile time, but to set the physical address only + * in the boot process. We allocate these special addresses + * from the end of virtual memory (0xfffff000) backwards. + * Also this lets us do fail-safe vmalloc(), we + * can guarantee that these special addresses and + * vmalloc()-ed addresses never overlap. + * + * these 'compile-time allocated' memory buffers are + * fixed-size 4k pages. (or larger if used with an increment + * highger than 1) use fixmap_set(idx,phys) to associate + * physical memory with fixmap indices. + * + * TLB entries of such buffers will not be flushed across + * task switches. + */ + +/* + * on UP currently we will have no trace of the fixmap mechanizm, + * no page table allocations, etc. This might change in the + * future, say framebuffers for the console driver(s) could be + * fix-mapped? + */ +enum fixed_addresses { +#define FIX_N_COLOURS 8 + FIX_CMAP_BEGIN, + FIX_CMAP_END = FIX_CMAP_BEGIN + FIX_N_COLOURS, + __end_of_fixed_addresses +}; + +/* + * used by vmalloc.c. + * + * Leave one empty page between vmalloc'ed areas and + * the start of the fixmap, and leave one page empty + * at the top of mem.. + */ +#define FIXADDR_TOP ((unsigned long)(long)(int)0xfefe0000) +#define FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) +#define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) + +#define __fix_to_virt(x) (FIXADDR_TOP - ((x) << PAGE_SHIFT)) +#define __virt_to_fix(x) \ + ((FIXADDR_TOP - ((x) & PAGE_MASK)) >> PAGE_SHIFT) + +extern void __this_fixmap_does_not_exist(void); + +/* + * 'index to address' translation. If anyone tries to use the idx + * directly without tranlation, we catch the bug with a NULL-deference + * kernel oops. Illegal ranges of incoming indices are caught too. + */ +static inline unsigned long fix_to_virt(const unsigned int idx) +{ + return __fix_to_virt(idx); +} + +static inline unsigned long virt_to_fix(const unsigned long vaddr) +{ + return __virt_to_fix(vaddr); +} + +#endif /* _ASM_SCORE_FIXMAP_H */ |