diff options
Diffstat (limited to 'arch/arm/include/asm/fixmap.h')
-rw-r--r-- | arch/arm/include/asm/fixmap.h | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h new file mode 100644 index 000000000000..bbae919bceb4 --- /dev/null +++ b/arch/arm/include/asm/fixmap.h @@ -0,0 +1,41 @@ +#ifndef _ASM_FIXMAP_H +#define _ASM_FIXMAP_H + +/* + * Nothing too fancy for now. + * + * On ARM we already have well known fixed virtual addresses imposed by + * the architecture such as the vector page which is located at 0xffff0000, + * therefore a second level page table is already allocated covering + * 0xfff00000 upwards. + * + * The cache flushing code in proc-xscale.S uses the virtual area between + * 0xfffe0000 and 0xfffeffff. + */ + +#define FIXADDR_START 0xfff00000UL +#define FIXADDR_TOP 0xfffe0000UL +#define FIXADDR_SIZE (FIXADDR_TOP - FIXADDR_START) + +#define FIX_KMAP_BEGIN 0 +#define FIX_KMAP_END (FIXADDR_SIZE >> PAGE_SHIFT) + +#define __fix_to_virt(x) (FIXADDR_START + ((x) << PAGE_SHIFT)) +#define __virt_to_fix(x) (((x) - FIXADDR_START) >> PAGE_SHIFT) + +extern void __this_fixmap_does_not_exist(void); + +static inline unsigned long fix_to_virt(const unsigned int idx) +{ + if (idx >= FIX_KMAP_END) + __this_fixmap_does_not_exist(); + return __fix_to_virt(idx); +} + +static inline unsigned int virt_to_fix(const unsigned long vaddr) +{ + BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START); + return __virt_to_fix(vaddr); +} + +#endif |