linux/arch/arm/mm/mm.h
Nicolas Pitre 5f0fbf9eca [ARM] fixmap support
This is the minimum fixmap interface expected to be implemented by
architectures supporting highmem.

We have a second level page table already allocated and covering
0xfff00000-0xffffffff because the exception vector page is located
at 0xffff0000, and various cache tricks already use some entries above
0xffff0000.  Therefore the PTEs covering 0xfff00000-0xfffeffff are free
to be used.

However the XScale cache flushing code already uses virtual addresses
between 0xfffe0000 and 0xfffeffff.

So this reserves the 0xfff00000-0xfffdffff range for fixmap stuff.

The Documentation/arm/memory.txt information is updated accordingly,
including the information about the actual top of DMA memory mapping
region which didn't match the code.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-15 21:01:20 -04:00

36 lines
696 B
C

#ifdef CONFIG_MMU
/* the upper-most page table pointer */
extern pmd_t *top_pmd;
#define TOP_PTE(x) pte_offset_kernel(top_pmd, x)
static inline pmd_t *pmd_off(pgd_t *pgd, unsigned long virt)
{
return pmd_offset(pgd, virt);
}
static inline pmd_t *pmd_off_k(unsigned long virt)
{
return pmd_off(pgd_offset_k(virt), virt);
}
struct mem_type {
unsigned int prot_pte;
unsigned int prot_l1;
unsigned int prot_sect;
unsigned int domain;
};
const struct mem_type *get_mem_type(unsigned int type);
#endif
struct map_desc;
struct meminfo;
struct pglist_data;
void __init create_mapping(struct map_desc *md);
void __init bootmem_init(void);
void reserve_node_zero(struct pglist_data *pgdat);