OpenCloudOS-Kernel/arch/arm/include/asm/fixmap.h

42 lines
1.1 KiB
C

#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