kernel-fxtec-pro1x/arch/sh/include/asm/pgtable.h
Matt Fleming 5d9b4b19f1 sh: Definitions for 3-level page table layout
If using 64-bit PTEs and 4K pages then each page table has 512 entries
(as opposed to 1024 entries with 32-bit PTEs). Unlike MIPS, SH follows
the convention that all structures in the page table (pgd_t, pmd_t,
pgprot_t, etc) must be the same size. Therefore, 64-bit PTEs require
64-bit PGD entries, etc. Using 2-levels of page tables and 64-bit PTEs
it is only possible to map 1GB of virtual address space.

In order to map all 4GB of virtual address space we need to adopt a
3-level page table layout. This actually works out better for
CONFIG_SUPERH32 because we only waste 2 PGD entries on the P1 and P2
areas (which are untranslated) instead of 256.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-12-17 14:31:20 +09:00

173 lines
4.2 KiB
C

/*
* This file contains the functions and defines necessary to modify and
* use the SuperH page table tree.
*
* Copyright (C) 1999 Niibe Yutaka
* Copyright (C) 2002 - 2007 Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file "COPYING" in the main directory of this
* archive for more details.
*/
#ifndef __ASM_SH_PGTABLE_H
#define __ASM_SH_PGTABLE_H
#ifdef CONFIG_PGTABLE_LEVELS_3
#include <asm/pgtable_pmd.h>
#else
#include <asm/pgtable_nopmd.h>
#endif
#include <asm/page.h>
#ifndef __ASSEMBLY__
#include <asm/addrspace.h>
#include <asm/fixmap.h>
/*
* ZERO_PAGE is a global shared page that is always zero: used
* for zero-mapped memory areas etc..
*/
extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
#endif /* !__ASSEMBLY__ */
/*
* Effective and physical address definitions, to aid with sign
* extension.
*/
#define NEFF 32
#define NEFF_SIGN (1LL << (NEFF - 1))
#define NEFF_MASK (-1LL << NEFF)
static inline unsigned long long neff_sign_extend(unsigned long val)
{
unsigned long long extended = val;
return (extended & NEFF_SIGN) ? (extended | NEFF_MASK) : extended;
}
#ifdef CONFIG_29BIT
#define NPHYS 29
#else
#define NPHYS 32
#endif
#define NPHYS_SIGN (1LL << (NPHYS - 1))
#define NPHYS_MASK (-1LL << NPHYS)
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE-1))
/* Entries per level */
#define PTRS_PER_PTE (PAGE_SIZE / (1 << PTE_MAGNITUDE))
#define FIRST_USER_ADDRESS 0
#define PHYS_ADDR_MASK29 0x1fffffff
#define PHYS_ADDR_MASK32 0xffffffff
#ifdef CONFIG_PMB
static inline unsigned long phys_addr_mask(void)
{
/* Is the MMU in 29bit mode? */
if (__in_29bit_mode())
return PHYS_ADDR_MASK29;
return PHYS_ADDR_MASK32;
}
#elif defined(CONFIG_32BIT)
static inline unsigned long phys_addr_mask(void)
{
return PHYS_ADDR_MASK32;
}
#else
static inline unsigned long phys_addr_mask(void)
{
return PHYS_ADDR_MASK29;
}
#endif
#define PTE_PHYS_MASK (phys_addr_mask() & PAGE_MASK)
#define PTE_FLAGS_MASK (~(PTE_PHYS_MASK) << PAGE_SHIFT)
#ifdef CONFIG_SUPERH32
#define VMALLOC_START (P3SEG)
#else
#define VMALLOC_START (0xf0000000)
#endif
#define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE)
#if defined(CONFIG_SUPERH32)
#include <asm/pgtable_32.h>
#else
#include <asm/pgtable_64.h>
#endif
/*
* SH-X and lower (legacy) SuperH parts (SH-3, SH-4, some SH-4A) can't do page
* protection for execute, and considers it the same as a read. Also, write
* permission implies read permission. This is the closest we can get..
*
* SH-X2 (SH7785) and later parts take this to the opposite end of the extreme,
* not only supporting separate execute, read, and write bits, but having
* completely separate permission bits for user and kernel space.
*/
/*xwr*/
#define __P000 PAGE_NONE
#define __P001 PAGE_READONLY
#define __P010 PAGE_COPY
#define __P011 PAGE_COPY
#define __P100 PAGE_EXECREAD
#define __P101 PAGE_EXECREAD
#define __P110 PAGE_COPY
#define __P111 PAGE_COPY
#define __S000 PAGE_NONE
#define __S001 PAGE_READONLY
#define __S010 PAGE_WRITEONLY
#define __S011 PAGE_SHARED
#define __S100 PAGE_EXECREAD
#define __S101 PAGE_EXECREAD
#define __S110 PAGE_RWX
#define __S111 PAGE_RWX
typedef pte_t *pte_addr_t;
#define kern_addr_valid(addr) (1)
#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
remap_pfn_range(vma, vaddr, pfn, size, prot)
#define pte_pfn(x) ((unsigned long)(((x).pte_low >> PAGE_SHIFT)))
/*
* No page table caches to initialise
*/
#define pgtable_cache_init() do { } while (0)
struct vm_area_struct;
extern void __update_cache(struct vm_area_struct *vma,
unsigned long address, pte_t pte);
extern void __update_tlb(struct vm_area_struct *vma,
unsigned long address, pte_t pte);
static inline void
update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t pte)
{
__update_cache(vma, address, pte);
__update_tlb(vma, address, pte);
}
extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
extern void paging_init(void);
extern void page_table_range_init(unsigned long start, unsigned long end,
pgd_t *pgd);
/* arch/sh/mm/mmap.c */
#define HAVE_ARCH_UNMAPPED_AREA
#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
#include <asm-generic/pgtable.h>
#endif /* __ASM_SH_PGTABLE_H */