1/*
  2 * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
  3 * Copyright (C) 2004 Microtronix Datacom Ltd.
  4 *
  5 * MMU support based on asm/page.h from mips which is:
  6 *
  7 * Copyright (C) 1994 - 1999, 2000, 03 Ralf Baechle
  8 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
  9 *
 10 * This file is subject to the terms and conditions of the GNU General Public
 11 * License.  See the file "COPYING" in the main directory of this archive
 12 * for more details.
 13 */
 14
 15#ifndef _ASM_NIOS2_PAGE_H
 16#define _ASM_NIOS2_PAGE_H
 17
 18#include <linux/pfn.h>
 19#include <linux/const.h>
 20
 21/*
 22 * PAGE_SHIFT determines the page size
 23 */
 24#define PAGE_SHIFT	12
 25#define PAGE_SIZE	(_AC(1, UL) << PAGE_SHIFT)
 26#define PAGE_MASK	(~(PAGE_SIZE - 1))
 27
 28/*
 29 * PAGE_OFFSET -- the first address of the first page of memory.
 30 */
 31#define PAGE_OFFSET	\
 32	(CONFIG_NIOS2_MEM_BASE + CONFIG_NIOS2_KERNEL_REGION_BASE)
 33
 34#ifndef __ASSEMBLY__
 35
 36/*
 37 * This gives the physical RAM offset.
 38 */
 39#define PHYS_OFFSET		CONFIG_NIOS2_MEM_BASE
 40
 41/*
 42 * It's normally defined only for FLATMEM config but it's
 43 * used in our early mem init code for all memory models.
 44 * So always define it.
 45 */
 46#define ARCH_PFN_OFFSET		PFN_UP(PHYS_OFFSET)
 47
 48#define clear_page(page)	memset((page), 0, PAGE_SIZE)
 49#define copy_page(to, from)	memcpy((to), (from), PAGE_SIZE)
 50
 51struct page;
 52
 53extern void clear_user_page(void *addr, unsigned long vaddr, struct page *page);
 54extern void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
 55				struct page *to);
 56
 57/*
 58 * These are used to make use of C type-checking.
 59 */
 60typedef struct page *pgtable_t;
 61typedef struct { unsigned long pte; } pte_t;
 62typedef struct { unsigned long pgd; } pgd_t;
 63typedef struct { unsigned long pgprot; } pgprot_t;
 64
 65#define pte_val(x)	((x).pte)
 66#define pgd_val(x)	((x).pgd)
 67#define pgprot_val(x)	((x).pgprot)
 68
 69#define __pte(x)	((pte_t) { (x) })
 70#define __pgd(x)	((pgd_t) { (x) })
 71#define __pgprot(x)	((pgprot_t) { (x) })
 72
 73extern unsigned long memory_start;
 74extern unsigned long memory_end;
 75extern unsigned long memory_size;
 76
 77extern struct page *mem_map;
 78
 79# define __pa(x)		\
 80	((unsigned long)(x) - PAGE_OFFSET + PHYS_OFFSET)
 81# define __va(x)		\
 82	((void *)((unsigned long)(x) + PAGE_OFFSET - PHYS_OFFSET))
 83
 84#define page_to_virt(page)	\
 85	((void *)(((page) - mem_map) << PAGE_SHIFT) + PAGE_OFFSET)
 86
 87# define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
 88
 89static inline bool pfn_valid(unsigned long pfn)
 90{
 91	/* avoid <linux/mm.h> include hell */
 92	extern unsigned long max_mapnr;
 93	unsigned long pfn_offset = ARCH_PFN_OFFSET;
 94
 95	return pfn >= pfn_offset && pfn < max_mapnr;
 96}
 97
 98# define virt_to_page(vaddr)	pfn_to_page(PFN_DOWN(virt_to_phys(vaddr)))
 99# define virt_addr_valid(vaddr)	pfn_valid(PFN_DOWN(virt_to_phys(vaddr)))
100
101# define VM_DATA_DEFAULT_FLAGS	VM_DATA_FLAGS_NON_EXEC
102
103#include <asm-generic/memory_model.h>
104
105#include <asm-generic/getorder.h>
106
107#endif /* !__ASSEMBLY__ */
108
109#endif /* _ASM_NIOS2_PAGE_H */