1/* 2 * include/asm-xtensa/page.h 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version2 as 6 * published by the Free Software Foundation. 7 * 8 * Copyright (C) 2001 - 2007 Tensilica Inc. 9 */ 10 11#ifndef _XTENSA_PAGE_H 12#define _XTENSA_PAGE_H 13 14#include <linux/const.h> 15 16#include <asm/processor.h> 17#include <asm/types.h> 18#include <asm/cache.h> 19#include <asm/kmem_layout.h> 20 21/* 22 * PAGE_SHIFT determines the page size 23 */ 24 25#define PAGE_SHIFT CONFIG_PAGE_SHIFT 26#define PAGE_SIZE (__XTENSA_UL_CONST(1) << PAGE_SHIFT) 27#define PAGE_MASK (~(PAGE_SIZE-1)) 28 29#ifdef CONFIG_MMU 30#define PAGE_OFFSET XCHAL_KSEG_CACHED_VADDR 31#define PHYS_OFFSET XCHAL_KSEG_PADDR 32#define MAX_LOW_PFN (PHYS_PFN(XCHAL_KSEG_PADDR) + \ 33 PHYS_PFN(XCHAL_KSEG_SIZE)) 34#else 35#define PAGE_OFFSET _AC(CONFIG_DEFAULT_MEM_START, UL) 36#define PHYS_OFFSET _AC(CONFIG_DEFAULT_MEM_START, UL) 37#define MAX_LOW_PFN PHYS_PFN(0xfffffffful) 38#endif 39 40/* 41 * Cache aliasing: 42 * 43 * If the cache size for one way is greater than the page size, we have to 44 * deal with cache aliasing. The cache index is wider than the page size: 45 * 46 * | |cache| cache index 47 * | pfn |off| virtual address 48 * |xxxx:X|zzz| 49 * | : | | 50 * | \ / | | 51 * |trans.| | 52 * | / \ | | 53 * |yyyy:Y|zzz| physical address 54 * 55 * When the page number is translated to the physical page address, the lowest 56 * bit(s) (X) that are part of the cache index are also translated (Y). 57 * If this translation changes bit(s) (X), the cache index is also afected, 58 * thus resulting in a different cache line than before. 59 * The kernel does not provide a mechanism to ensure that the page color 60 * (represented by this bit) remains the same when allocated or when pages 61 * are remapped. When user pages are mapped into kernel space, the color of 62 * the page might also change. 63 * 64 * We use the address space VMALLOC_END ... VMALLOC_END + DCACHE_WAY_SIZE * 2 65 * to temporarily map a patch so we can match the color. 66 */ 67 68#if DCACHE_WAY_SIZE > PAGE_SIZE 69# define DCACHE_ALIAS_ORDER (DCACHE_WAY_SHIFT - PAGE_SHIFT) 70# define DCACHE_ALIAS_MASK (PAGE_MASK & (DCACHE_WAY_SIZE - 1)) 71# define DCACHE_ALIAS(a) (((a) & DCACHE_ALIAS_MASK) >> PAGE_SHIFT) 72# define DCACHE_ALIAS_EQ(a,b) ((((a) ^ (b)) & DCACHE_ALIAS_MASK) == 0) 73#else 74# define DCACHE_ALIAS_ORDER 0 75# define DCACHE_ALIAS(a) ((void)(a), 0) 76#endif 77#define DCACHE_N_COLORS (1 << DCACHE_ALIAS_ORDER) 78 79#if ICACHE_WAY_SIZE > PAGE_SIZE 80# define ICACHE_ALIAS_ORDER (ICACHE_WAY_SHIFT - PAGE_SHIFT) 81# define ICACHE_ALIAS_MASK (PAGE_MASK & (ICACHE_WAY_SIZE - 1)) 82# define ICACHE_ALIAS(a) (((a) & ICACHE_ALIAS_MASK) >> PAGE_SHIFT) 83# define ICACHE_ALIAS_EQ(a,b) ((((a) ^ (b)) & ICACHE_ALIAS_MASK) == 0) 84#else 85# define ICACHE_ALIAS_ORDER 0 86#endif 87 88 89#ifdef __ASSEMBLY__ 90 91#define __pgprot(x) (x) 92 93#else 94 95/* 96 * These are used to make use of C type-checking.. 97 */ 98 99typedef struct { unsigned long pte; } pte_t; /* page table entry */ 100typedef struct { unsigned long pgd; } pgd_t; /* PGD table entry */ 101typedef struct { unsigned long pgprot; } pgprot_t; 102typedef struct page *pgtable_t; 103 104#define pte_val(x) ((x).pte) 105#define pgd_val(x) ((x).pgd) 106#define pgprot_val(x) ((x).pgprot) 107 108#define __pte(x) ((pte_t) { (x) } ) 109#define __pgd(x) ((pgd_t) { (x) } ) 110#define __pgprot(x) ((pgprot_t) { (x) } ) 111 112/* 113 * Pure 2^n version of get_order 114 * Use 'nsau' instructions if supported by the processor or the generic version. 115 */ 116 117#if XCHAL_HAVE_NSA 118 119static inline __attribute_const__ int get_order(unsigned long size) 120{ 121 int lz; 122 asm ("nsau %0, %1" : "=r" (lz) : "r" ((size - 1) >> PAGE_SHIFT)); 123 return 32 - lz; 124} 125 126#else 127 128# include <asm-generic/getorder.h> 129 130#endif 131 132struct page; 133struct vm_area_struct; 134extern void clear_page(void *page); 135extern void copy_page(void *to, void *from); 136 137/* 138 * If we have cache aliasing and writeback caches, we might have to do 139 * some extra work 140 */ 141 142#if defined(CONFIG_MMU) && DCACHE_WAY_SIZE > PAGE_SIZE 143extern void clear_page_alias(void *vaddr, unsigned long paddr); 144extern void copy_page_alias(void *to, void *from, 145 unsigned long to_paddr, unsigned long from_paddr); 146 147#define clear_user_highpage clear_user_highpage 148void clear_user_highpage(struct page *page, unsigned long vaddr); 149#define __HAVE_ARCH_COPY_USER_HIGHPAGE 150void copy_user_highpage(struct page *to, struct page *from, 151 unsigned long vaddr, struct vm_area_struct *vma); 152#else 153# define clear_user_page(page, vaddr, pg) clear_page(page) 154# define copy_user_page(to, from, vaddr, pg) copy_page(to, from) 155#endif 156 157/* 158 * This handles the memory map. We handle pages at 159 * XCHAL_KSEG_CACHED_VADDR for kernels with 32 bit address space. 160 * These macros are for conversion of kernel address, not user 161 * addresses. 162 */ 163 164#define ARCH_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT) 165 166#ifdef CONFIG_MMU 167static inline unsigned long ___pa(unsigned long va) 168{ 169 unsigned long off = va - PAGE_OFFSET; 170 171 if (off >= XCHAL_KSEG_SIZE) 172 off -= XCHAL_KSEG_SIZE; 173 174#ifndef CONFIG_XIP_KERNEL 175 return off + PHYS_OFFSET; 176#else 177 if (off < XCHAL_KSEG_SIZE) 178 return off + PHYS_OFFSET; 179 180 off -= XCHAL_KSEG_SIZE; 181 if (off >= XCHAL_KIO_SIZE) 182 off -= XCHAL_KIO_SIZE; 183 184 return off + XCHAL_KIO_PADDR; 185#endif 186} 187#define __pa(x) ___pa((unsigned long)(x)) 188#else 189#define __pa(x) \ 190 ((unsigned long) (x) - PAGE_OFFSET + PHYS_OFFSET) 191#endif 192#define __va(x) \ 193 ((void *)((unsigned long) (x) - PHYS_OFFSET + PAGE_OFFSET)) 194 195#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT) 196#define page_to_virt(page) __va(page_to_pfn(page) << PAGE_SHIFT) 197#define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT) 198#define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT) 199 200#endif /* __ASSEMBLY__ */ 201 202#include <asm-generic/memory_model.h> 203#endif /* _XTENSA_PAGE_H */ 204