1#ifndef _M68K_PGTABLE_H 2#define _M68K_PGTABLE_H 3 4#include <linux/config.h> 5#include <asm/setup.h> 6 7#ifndef __ASSEMBLY__ 8#include <asm/processor.h> 9#include <linux/threads.h> 10 11/* 12 * This file contains the functions and defines necessary to modify and use 13 * the m68k page table tree. 14 */ 15 16#include <asm/virtconvert.h> 17 18/* Certain architectures need to do special things when pte's 19 * within a page table are directly modified. Thus, the following 20 * hook is made available. 21 */ 22#define set_pte(pteptr, pteval) \ 23 do{ \ 24 *(pteptr) = (pteval); \ 25 } while(0) 26 27 28/* PMD_SHIFT determines the size of the area a second-level page table can map */ 29#ifdef CONFIG_SUN3 30#define PMD_SHIFT 17 31#else 32#define PMD_SHIFT 22 33#endif 34#define PMD_SIZE (1UL << PMD_SHIFT) 35#define PMD_MASK (~(PMD_SIZE-1)) 36 37/* PGDIR_SHIFT determines what a third-level page table entry can map */ 38#ifdef CONFIG_SUN3 39#define PGDIR_SHIFT 17 40#else 41#define PGDIR_SHIFT 25 42#endif 43#define PGDIR_SIZE (1UL << PGDIR_SHIFT) 44#define PGDIR_MASK (~(PGDIR_SIZE-1)) 45 46/* 47 * entries per page directory level: the m68k is configured as three-level, 48 * so we do have PMD level physically. 49 */ 50#ifdef CONFIG_SUN3 51#define PTRS_PER_PTE 16 52#define PTRS_PER_PMD 1 53#define PTRS_PER_PGD 2048 54#else 55#define PTRS_PER_PTE 1024 56#define PTRS_PER_PMD 8 57#define PTRS_PER_PGD 128 58#endif 59#define USER_PTRS_PER_PGD (TASK_SIZE/PGDIR_SIZE) 60#define FIRST_USER_PGD_NR 0 61 62/* Virtual address region for use by kernel_map() */ 63#ifdef CONFIG_SUN3 64#define KMAP_START 0x0DC00000 65#define KMAP_END 0x0E000000 66#else 67#define KMAP_START 0xd0000000 68#define KMAP_END 0xf0000000 69#endif 70 71#ifndef CONFIG_SUN3 72/* Just any arbitrary offset to the start of the vmalloc VM area: the 73 * current 8MB value just means that there will be a 8MB "hole" after the 74 * physical memory until the kernel virtual memory starts. That means that 75 * any out-of-bounds memory accesses will hopefully be caught. 76 * The vmalloc() routines leaves a hole of 4kB between each vmalloced 77 * area for the same reason. ;) 78 */ 79#define VMALLOC_OFFSET (8*1024*1024) 80#define VMALLOC_START (((unsigned long) high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)) 81#define VMALLOC_VMADDR(x) ((unsigned long)(x)) 82#define VMALLOC_END KMAP_START 83#else 84extern unsigned long vmalloc_end; 85#define VMALLOC_START 0x0f800000 86#define VMALLOC_VMADDR(x) ((unsigned long)(x)) 87#define VMALLOC_END vmalloc_end 88#endif /* CONFIG_SUN3 */ 89 90/* zero page used for uninitialized stuff */ 91extern unsigned long empty_zero_page; 92 93/* 94 * BAD_PAGETABLE is used when we need a bogus page-table, while 95 * BAD_PAGE is used for a bogus page. 96 * 97 * ZERO_PAGE is a global shared page that is always zero: used 98 * for zero-mapped memory areas etc.. 99 */ 100extern pte_t __bad_page(void); 101extern pte_t * __bad_pagetable(void); 102 103#define BAD_PAGETABLE __bad_pagetable() 104#define BAD_PAGE __bad_page() 105#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page)) 106 107/* number of bits that fit into a memory pointer */ 108#define BITS_PER_PTR (8*sizeof(unsigned long)) 109 110/* to align the pointer to a pointer address */ 111#define PTR_MASK (~(sizeof(void*)-1)) 112 113/* sizeof(void*)==1<<SIZEOF_PTR_LOG2 */ 114/* 64-bit machines, beware! SRB. */ 115#define SIZEOF_PTR_LOG2 2 116 117/* 118 * Check if the addr/len goes up to the end of a physical 119 * memory chunk. Used for DMA functions. 120 */ 121#ifdef CONFIG_SINGLE_MEMORY_CHUNK 122/* 123 * It makes no sense to consider whether we cross a memory boundary if 124 * we support just one physical chunk of memory. 125 */ 126static inline int mm_end_of_chunk(unsigned long addr, int len) 127{ 128 return 0; 129} 130#else 131int mm_end_of_chunk (unsigned long addr, int len); 132#endif 133 134extern void kernel_set_cachemode(void *addr, unsigned long size, int cmode); 135 136/* 137 * The m68k doesn't have any external MMU info: the kernel page 138 * tables contain all the necessary information. The Sun3 does, but 139 * they are updated on demand. 140 */ 141static inline void update_mmu_cache(struct vm_area_struct *vma, 142 unsigned long address, pte_t pte) 143{ 144} 145 146#ifdef CONFIG_SUN3 147/* Macros to (de)construct the fake PTEs representing swap pages. */ 148#define SWP_TYPE(x) ((x).val & 0x7F) 149#define SWP_OFFSET(x) (((x).val) >> 7) 150#define SWP_ENTRY(type,offset) ((swp_entry_t) { ((type) | ((offset) << 7)) }) 151#define pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 152#define swp_entry_to_pte(x) ((pte_t) { (x).val }) 153 154#else 155 156/* Encode and de-code a swap entry (must be !pte_none(e) && !pte_present(e)) */ 157#define SWP_TYPE(x) (((x).val >> 3) & 0x1ff) 158#define SWP_OFFSET(x) ((x).val >> 12) 159#define SWP_ENTRY(type, offset) ((swp_entry_t) { ((type) << 3) | ((offset) << 12) }) 160#define pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) 161#define swp_entry_to_pte(x) ((pte_t) { (x).val }) 162 163#endif /* CONFIG_SUN3 */ 164 165#endif /* !__ASSEMBLY__ */ 166 167/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */ 168#define PageSkip(page) (0) 169#define kern_addr_valid(addr) (1) 170 171#define io_remap_page_range remap_page_range 172 173/* MMU-specific headers */ 174 175#ifdef CONFIG_SUN3 176#include <asm/sun3_pgtable.h> 177#else 178#include <asm/motorola_pgtable.h> 179#endif 180 181#ifndef __ASSEMBLY__ 182#include <asm-generic/pgtable.h> 183#endif /* !__ASSEMBLY__ */ 184 185/* 186 * No page table caches to initialise 187 */ 188#define pgtable_cache_init() do { } while (0) 189 190#endif /* _M68K_PGTABLE_H */ 191