1 /* 2 * linux/arch/m68k/mm/kmap.c 3 * 4 * Copyright (C) 1997 Roman Hodek 5 * 6 * 10/01/99 cleaned up the code and changing to the same interface 7 * used by other architectures /Roman Zippel 8 */ 9 10 #include <linux/mm.h> 11 #include <linux/kernel.h> 12 #include <linux/string.h> 13 #include <linux/types.h> 14 #include <linux/slab.h> 15 #include <linux/vmalloc.h> 16 17 #include <asm/setup.h> 18 #include <asm/segment.h> 19 #include <asm/page.h> 20 #include <asm/pgalloc.h> 21 #include <asm/io.h> 22 #include <asm/system.h> 23 24 #undef DEBUG 25 26 #define PTRTREESIZE (256*1024) 27 28 /* 29 * For 040/060 we can use the virtual memory area like other architectures, 30 * but for 020/030 we want to use early termination page descriptor and we 31 * can't mix this with normal page descriptors, so we have to copy that code 32 * (mm/vmalloc.c) and return appriorate aligned addresses. 33 */ 34 35 #ifdef CPU_M68040_OR_M68060_ONLY 36 37 #define IO_SIZE PAGE_SIZE 38 39 static inline struct vm_struct *get_io_area(unsigned long size) 40 { 41 return get_vm_area(size, VM_IOREMAP); 42 } 43 44 45 static inline void free_io_area(void *addr) 46 { 47 vfree((void *)(PAGE_MASK & (unsigned long)addr)); 48 } 49 50 #else 51 52 #define IO_SIZE (256*1024) 53 54 static struct vm_struct *iolist; 55 56 static struct vm_struct *get_io_area(unsigned long size) 57 { 58 unsigned long addr; 59 struct vm_struct **p, *tmp, *area; 60 61 area = (struct vm_struct *)kmalloc(sizeof(*area), GFP_KERNEL); 62 if (!area) 63 return NULL; 64 addr = KMAP_START; 65 for (p = &iolist; (tmp = *p) ; p = &tmp->next) { 66 if (size + addr < (unsigned long)tmp->addr) 67 break; 68 if (addr > KMAP_END-size) 69 return NULL; 70 addr = tmp->size + (unsigned long)tmp->addr; 71 } 72 area->addr = (void *)addr; 73 area->size = size + IO_SIZE; 74 area->next = *p; 75 *p = area; 76 return area; 77 } 78 79 static inline void free_io_area(void *addr) 80 { 81 struct vm_struct **p, *tmp; 82 83 if (!addr) 84 return; 85 addr = (void *)((unsigned long)addr & -IO_SIZE); 86 for (p = &iolist ; (tmp = *p) ; p = &tmp->next) { 87 if (tmp->addr == addr) { 88 *p = tmp->next; 89 __iounmap(tmp->addr, tmp->size); 90 kfree(tmp); 91 return; 92 } 93 } 94 } 95 96 #endif 97 98 /* 99 * Map some physical address range into the kernel address space. The 100 * code is copied and adapted from map_chunk(). 101 */ 102 /* Rewritten by Andreas Schwab to remove all races. */ 103 104 void __iomem *__ioremap(unsigned long physaddr, unsigned long size, int cacheflag) 105 { 106 struct vm_struct *area; 107 unsigned long virtaddr, retaddr; 108 long offset; 109 pgd_t *pgd_dir; 110 pmd_t *pmd_dir; 111 pte_t *pte_dir; 112 113 /* 114 * Don't allow mappings that wrap.. 115 */ 116 if (!size || size > physaddr + size) 117 return NULL; 118 119 #ifdef CONFIG_AMIGA 120 if (MACH_IS_AMIGA) { 121 if ((physaddr >= 0x40000000) && (physaddr + size < 0x60000000) 122 && (cacheflag == IOMAP_NOCACHE_SER)) 123 return (void __iomem *)physaddr; 124 } 125 #endif 126 127 #ifdef DEBUG 128 printk("ioremap: 0x%lx,0x%lx(%d) - ", physaddr, size, cacheflag); 129 #endif 130 /* 131 * Mappings have to be aligned 132 */ 133 offset = physaddr & (IO_SIZE - 1); 134 physaddr &= -IO_SIZE; 135 size = (size + offset + IO_SIZE - 1) & -IO_SIZE; 136 137 /* 138 * Ok, go for it.. 139 */ 140 area = get_io_area(size); 141 if (!area) 142 return NULL; 143 144 virtaddr = (unsigned long)area->addr; 145 retaddr = virtaddr + offset; 146 #ifdef DEBUG 147 printk("0x%lx,0x%lx,0x%lx", physaddr, virtaddr, retaddr); 148 #endif 149 150 /* 151 * add cache and table flags to physical address 152 */ 153 if (CPU_IS_040_OR_060) { 154 physaddr |= (_PAGE_PRESENT | _PAGE_GLOBAL040 | 155 _PAGE_ACCESSED | _PAGE_DIRTY); 156 switch (cacheflag) { 157 case IOMAP_FULL_CACHING: 158 physaddr |= _PAGE_CACHE040; 159 break; 160 case IOMAP_NOCACHE_SER: 161 default: 162 physaddr |= _PAGE_NOCACHE_S; 163 break; 164 case IOMAP_NOCACHE_NONSER: 165 physaddr |= _PAGE_NOCACHE; 166 break; 167 case IOMAP_WRITETHROUGH: 168 physaddr |= _PAGE_CACHE040W; 169 break; 170 } 171 } else { 172 physaddr |= (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY); 173 switch (cacheflag) { 174 case IOMAP_NOCACHE_SER: 175 case IOMAP_NOCACHE_NONSER: 176 default: 177 physaddr |= _PAGE_NOCACHE030; 178 break; 179 case IOMAP_FULL_CACHING: 180 case IOMAP_WRITETHROUGH: 181 break; 182 } 183 } 184 185 while ((long)size > 0) { 186 #ifdef DEBUG 187 if (!(virtaddr & (PTRTREESIZE-1))) 188 printk ("\npa=%#lx va=%#lx ", physaddr, virtaddr); 189 #endif 190 pgd_dir = pgd_offset_k(virtaddr); 191 pmd_dir = pmd_alloc(&init_mm, pgd_dir, virtaddr); 192 if (!pmd_dir) { 193 printk("ioremap: no mem for pmd_dir\n"); 194 return NULL; 195 } 196 197 if (CPU_IS_020_OR_030) { 198 pmd_dir->pmd[(virtaddr/PTRTREESIZE) & 15] = physaddr; 199 physaddr += PTRTREESIZE; 200 virtaddr += PTRTREESIZE; 201 size -= PTRTREESIZE; 202 } else { 203 pte_dir = pte_alloc_kernel(pmd_dir, virtaddr); 204 if (!pte_dir) { 205 printk("ioremap: no mem for pte_dir\n"); 206 return NULL; 207 } 208 209 pte_val(*pte_dir) = physaddr; 210 virtaddr += PAGE_SIZE; 211 physaddr += PAGE_SIZE; 212 size -= PAGE_SIZE; 213 } 214 } 215 #ifdef DEBUG 216 printk("\n"); 217 #endif 218 flush_tlb_all(); 219 220 return (void __iomem *)retaddr; 221 } 222 223 /* 224 * Unmap a ioremap()ed region again 225 */ 226 void iounmap(void __iomem *addr) 227 { 228 #ifdef CONFIG_AMIGA 229 if ((!MACH_IS_AMIGA) || 230 (((unsigned long)addr < 0x40000000) || 231 ((unsigned long)addr > 0x60000000))) 232 free_io_area((__force void *)addr); 233 #else 234 free_io_area((__force void *)addr); 235 #endif 236 } 237 238 /* 239 * __iounmap unmaps nearly everything, so be careful 240 * it doesn't free currently pointer/page tables anymore but it 241 * wans't used anyway and might be added later. 242 */ 243 void __iounmap(void *addr, unsigned long size) 244 { 245 unsigned long virtaddr = (unsigned long)addr; 246 pgd_t *pgd_dir; 247 pmd_t *pmd_dir; 248 pte_t *pte_dir; 249 250 while ((long)size > 0) { 251 pgd_dir = pgd_offset_k(virtaddr); 252 if (pgd_bad(*pgd_dir)) { 253 printk("iounmap: bad pgd(%08lx)\n", pgd_val(*pgd_dir)); 254 pgd_clear(pgd_dir); 255 return; 256 } 257 pmd_dir = pmd_offset(pgd_dir, virtaddr); 258 259 if (CPU_IS_020_OR_030) { 260 int pmd_off = (virtaddr/PTRTREESIZE) & 15; 261 int pmd_type = pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK; 262 263 if (pmd_type == _PAGE_PRESENT) { 264 pmd_dir->pmd[pmd_off] = 0; 265 virtaddr += PTRTREESIZE; 266 size -= PTRTREESIZE; 267 continue; 268 } else if (pmd_type == 0) 269 continue; 270 } 271 272 if (pmd_bad(*pmd_dir)) { 273 printk("iounmap: bad pmd (%08lx)\n", pmd_val(*pmd_dir)); 274 pmd_clear(pmd_dir); 275 return; 276 } 277 pte_dir = pte_offset_kernel(pmd_dir, virtaddr); 278 279 pte_val(*pte_dir) = 0; 280 virtaddr += PAGE_SIZE; 281 size -= PAGE_SIZE; 282 } 283 284 flush_tlb_all(); 285 } 286 287 /* 288 * Set new cache mode for some kernel address space. 289 * The caller must push data for that range itself, if such data may already 290 * be in the cache. 291 */ 292 void kernel_set_cachemode(void *addr, unsigned long size, int cmode) 293 { 294 unsigned long virtaddr = (unsigned long)addr; 295 pgd_t *pgd_dir; 296 pmd_t *pmd_dir; 297 pte_t *pte_dir; 298 299 if (CPU_IS_040_OR_060) { 300 switch (cmode) { 301 case IOMAP_FULL_CACHING: 302 cmode = _PAGE_CACHE040; 303 break; 304 case IOMAP_NOCACHE_SER: 305 default: 306 cmode = _PAGE_NOCACHE_S; 307 break; 308 case IOMAP_NOCACHE_NONSER: 309 cmode = _PAGE_NOCACHE; 310 break; 311 case IOMAP_WRITETHROUGH: 312 cmode = _PAGE_CACHE040W; 313 break; 314 } 315 } else { 316 switch (cmode) { 317 case IOMAP_NOCACHE_SER: 318 case IOMAP_NOCACHE_NONSER: 319 default: 320 cmode = _PAGE_NOCACHE030; 321 break; 322 case IOMAP_FULL_CACHING: 323 case IOMAP_WRITETHROUGH: 324 cmode = 0; 325 } 326 } 327 328 while ((long)size > 0) { 329 pgd_dir = pgd_offset_k(virtaddr); 330 if (pgd_bad(*pgd_dir)) { 331 printk("iocachemode: bad pgd(%08lx)\n", pgd_val(*pgd_dir)); 332 pgd_clear(pgd_dir); 333 return; 334 } 335 pmd_dir = pmd_offset(pgd_dir, virtaddr); 336 337 if (CPU_IS_020_OR_030) { 338 int pmd_off = (virtaddr/PTRTREESIZE) & 15; 339 340 if ((pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK) == _PAGE_PRESENT) { 341 pmd_dir->pmd[pmd_off] = (pmd_dir->pmd[pmd_off] & 342 _CACHEMASK040) | cmode; 343 virtaddr += PTRTREESIZE; 344 size -= PTRTREESIZE; 345 continue; 346 } 347 } 348 349 if (pmd_bad(*pmd_dir)) { 350 printk("iocachemode: bad pmd (%08lx)\n", pmd_val(*pmd_dir)); 351 pmd_clear(pmd_dir); 352 return; 353 } 354 pte_dir = pte_offset_kernel(pmd_dir, virtaddr); 355 356 pte_val(*pte_dir) = (pte_val(*pte_dir) & _CACHEMASK040) | cmode; 357 virtaddr += PAGE_SIZE; 358 size -= PAGE_SIZE; 359 } 360 361 flush_tlb_all(); 362 } 363