kernel-ark/include/asm-mips/page.h
Franck Bui-Huu 6f284a2ce7 [MIPS] FLATMEM: introduce PHYS_OFFSET.
The old code was assuming that min_low_pfn was always 0. This
means that platforms having a big hole at their memory start
paid the price of wasting some memory for the allocation of
unused entries in mem_map[].

This patch prevents this waste.

It introduces PHYS_OFFSET define which is the start of the
physical memory and uses it wherever needed. Specially when
converting physical/virtual addresses into virtual/physical
ones.

Currently all platforms defines PHYS_OFFSET to 0.

Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-02-06 16:53:13 +00:00

203 lines
5.3 KiB
C

/*
* 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.
*
* Copyright (C) 1994 - 1999, 2000, 03 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
*/
#ifndef _ASM_PAGE_H
#define _ASM_PAGE_H
#ifdef __KERNEL__
#include <spaces.h>
/*
* PAGE_SHIFT determines the page size
*/
#ifdef CONFIG_PAGE_SIZE_4KB
#define PAGE_SHIFT 12
#endif
#ifdef CONFIG_PAGE_SIZE_8KB
#define PAGE_SHIFT 13
#endif
#ifdef CONFIG_PAGE_SIZE_16KB
#define PAGE_SHIFT 14
#endif
#ifdef CONFIG_PAGE_SIZE_64KB
#define PAGE_SHIFT 16
#endif
#define PAGE_SIZE (1UL << PAGE_SHIFT)
#define PAGE_MASK (~((1 << PAGE_SHIFT) - 1))
#ifndef __ASSEMBLY__
/*
* This gives the physical RAM offset.
*/
#ifndef PHYS_OFFSET
#define PHYS_OFFSET 0UL
#endif
/*
* It's normally defined only for FLATMEM config but it's
* used in our early mem init code for all memory models.
* So always define it.
*/
#define ARCH_PFN_OFFSET PFN_UP(PHYS_OFFSET)
#include <linux/pfn.h>
#include <asm/io.h>
extern void clear_page(void * page);
extern void copy_page(void * to, void * from);
extern unsigned long shm_align_mask;
static inline unsigned long pages_do_alias(unsigned long addr1,
unsigned long addr2)
{
return (addr1 ^ addr2) & shm_align_mask;
}
struct page;
static inline void clear_user_page(void *addr, unsigned long vaddr,
struct page *page)
{
extern void (*flush_data_cache_page)(unsigned long addr);
clear_page(addr);
if (pages_do_alias((unsigned long) addr, vaddr & PAGE_MASK))
flush_data_cache_page((unsigned long)addr);
}
extern void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
struct page *to);
struct vm_area_struct;
extern void copy_user_highpage(struct page *to, struct page *from,
unsigned long vaddr, struct vm_area_struct *vma);
#define __HAVE_ARCH_COPY_USER_HIGHPAGE
/*
* These are used to make use of C type-checking..
*/
#ifdef CONFIG_64BIT_PHYS_ADDR
#ifdef CONFIG_CPU_MIPS32
typedef struct { unsigned long pte_low, pte_high; } pte_t;
#define pte_val(x) ((x).pte_low | ((unsigned long long)(x).pte_high << 32))
#define __pte(x) ({ pte_t __pte = {(x), ((unsigned long long)(x)) >> 32}; __pte; })
#else
typedef struct { unsigned long long pte; } pte_t;
#define pte_val(x) ((x).pte)
#define __pte(x) ((pte_t) { (x) } )
#endif
#else
typedef struct { unsigned long pte; } pte_t;
#define pte_val(x) ((x).pte)
#define __pte(x) ((pte_t) { (x) } )
#endif
/*
* For 3-level pagetables we defines these ourselves, for 2-level the
* definitions are supplied by <asm-generic/pgtable-nopmd.h>.
*/
#ifdef CONFIG_64BIT
typedef struct { unsigned long pmd; } pmd_t;
#define pmd_val(x) ((x).pmd)
#define __pmd(x) ((pmd_t) { (x) } )
#endif
/*
* Right now we don't support 4-level pagetables, so all pud-related
* definitions come from <asm-generic/pgtable-nopud.h>.
*/
/*
* Finall the top of the hierarchy, the pgd
*/
typedef struct { unsigned long pgd; } pgd_t;
#define pgd_val(x) ((x).pgd)
#define __pgd(x) ((pgd_t) { (x) } )
/*
* Manipulate page protection bits
*/
typedef struct { unsigned long pgprot; } pgprot_t;
#define pgprot_val(x) ((x).pgprot)
#define __pgprot(x) ((pgprot_t) { (x) } )
/*
* On R4000-style MMUs where a TLB entry is mapping a adjacent even / odd
* pair of pages we only have a single global bit per pair of pages. When
* writing to the TLB make sure we always have the bit set for both pages
* or none. This macro is used to access the `buddy' of the pte we're just
* working on.
*/
#define ptep_buddy(x) ((pte_t *)((unsigned long)(x) ^ sizeof(pte_t)))
#endif /* !__ASSEMBLY__ */
/* to align the pointer to the (next) page boundary */
#define PAGE_ALIGN(addr) (((addr) + PAGE_SIZE - 1) & PAGE_MASK)
/*
* __pa()/__va() should be used only during mem init.
*/
#if defined(CONFIG_64BIT) && !defined(CONFIG_BUILD_ELF64)
#define __pa_page_offset(x) ((unsigned long)(x) < CKSEG0 ? PAGE_OFFSET : CKSEG0)
#else
#define __pa_page_offset(x) PAGE_OFFSET
#endif
#define __pa(x) ((unsigned long)(x) - __pa_page_offset(x) + PHYS_OFFSET)
#define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET - PHYS_OFFSET))
#define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x),0))
#define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
#ifdef CONFIG_FLATMEM
#define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < max_mapnr)
#elif defined(CONFIG_SPARSEMEM)
/* pfn_valid is defined in linux/mmzone.h */
#elif defined(CONFIG_NEED_MULTIPLE_NODES)
#define pfn_valid(pfn) \
({ \
unsigned long __pfn = (pfn); \
int __n = pfn_to_nid(__pfn); \
((__n >= 0) ? (__pfn < NODE_DATA(__n)->node_start_pfn + \
NODE_DATA(__n)->node_spanned_pages) \
: 0); \
})
#endif
#define virt_to_page(kaddr) pfn_to_page(PFN_DOWN(virt_to_phys(kaddr)))
#define virt_addr_valid(kaddr) pfn_valid(PFN_DOWN(virt_to_phys(kaddr)))
#define VM_DATA_DEFAULT_FLAGS (VM_READ | VM_WRITE | VM_EXEC | \
VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
#define UNCAC_ADDR(addr) ((addr) - PAGE_OFFSET + UNCAC_BASE)
#define CAC_ADDR(addr) ((addr) - UNCAC_BASE + PAGE_OFFSET)
#ifdef CONFIG_LIMITED_DMA
#define WANT_PAGE_VIRTUAL
#endif
#include <asm-generic/memory_model.h>
#include <asm-generic/page.h>
#endif /* defined (__KERNEL__) */
#endif /* _ASM_PAGE_H */