1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/arch/m68k/mm/kmap.c 4 * 5 * Copyright (C) 1997 Roman Hodek 6 * 7 * 10/01/99 cleaned up the code and changing to the same interface 8 * used by other architectures /Roman Zippel 9 */ 10 11 #include <linux/module.h> 12 #include <linux/mm.h> 13 #include <linux/kernel.h> 14 #include <linux/string.h> 15 #include <linux/types.h> 16 #include <linux/slab.h> 17 #include <linux/vmalloc.h> 18 19 #include <asm/setup.h> 20 #include <asm/segment.h> 21 #include <asm/page.h> 22 #include <asm/pgalloc.h> 23 #include <asm/io.h> 24 25 #undef DEBUG 26 27 #define PTRTREESIZE (256*1024) 28 29 /* 30 * For 040/060 we can use the virtual memory area like other architectures, 31 * but for 020/030 we want to use early termination page descriptors and we 32 * can't mix this with normal page descriptors, so we have to copy that code 33 * (mm/vmalloc.c) and return appropriately aligned addresses. 34 */ 35 36 #ifdef CPU_M68040_OR_M68060_ONLY 37 38 #define IO_SIZE PAGE_SIZE 39 40 static inline struct vm_struct *get_io_area(unsigned long size) 41 { 42 return get_vm_area(size, VM_IOREMAP); 43 } 44 45 46 static inline void free_io_area(void *addr) 47 { 48 vfree((void *)(PAGE_MASK & (unsigned long)addr)); 49 } 50 51 #else 52 53 #define IO_SIZE (256*1024) 54 55 static struct vm_struct *iolist; 56 57 static struct vm_struct *get_io_area(unsigned long size) 58 { 59 unsigned long addr; 60 struct vm_struct **p, *tmp, *area; 61 62 area = kmalloc(sizeof(*area), GFP_KERNEL); 63 if (!area) 64 return NULL; 65 addr = KMAP_START; 66 for (p = &iolist; (tmp = *p) ; p = &tmp->next) { 67 if (size + addr < (unsigned long)tmp->addr) 68 break; 69 if (addr > KMAP_END-size) { 70 kfree(area); 71 return NULL; 72 } 73 addr = tmp->size + (unsigned long)tmp->addr; 74 } 75 area->addr = (void *)addr; 76 area->size = size + IO_SIZE; 77 area->next = *p; 78 *p = area; 79 return area; 80 } 81 82 static inline void free_io_area(void *addr) 83 { 84 struct vm_struct **p, *tmp; 85 86 if (!addr) 87 return; 88 addr = (void *)((unsigned long)addr & -IO_SIZE); 89 for (p = &iolist ; (tmp = *p) ; p = &tmp->next) { 90 if (tmp->addr == addr) { 91 *p = tmp->next; 92 /* remove gap added in get_io_area() */ 93 __iounmap(tmp->addr, tmp->size - IO_SIZE); 94 kfree(tmp); 95 return; 96 } 97 } 98 } 99 100 #endif 101 102 /* 103 * Map some physical address range into the kernel address space. 104 */ 105 /* Rewritten by Andreas Schwab to remove all races. */ 106 107 void __iomem *__ioremap(unsigned long physaddr, unsigned long size, int cacheflag) 108 { 109 struct vm_struct *area; 110 unsigned long virtaddr, retaddr; 111 long offset; 112 pgd_t *pgd_dir; 113 pmd_t *pmd_dir; 114 pte_t *pte_dir; 115 116 /* 117 * Don't allow mappings that wrap.. 118 */ 119 if (!size || physaddr > (unsigned long)(-size)) 120 return NULL; 121 122 #ifdef CONFIG_AMIGA 123 if (MACH_IS_AMIGA) { 124 if ((physaddr >= 0x40000000) && (physaddr + size < 0x60000000) 125 && (cacheflag == IOMAP_NOCACHE_SER)) 126 return (void __iomem *)physaddr; 127 } 128 #endif 129 #ifdef CONFIG_COLDFIRE 130 if (__cf_internalio(physaddr)) 131 return (void __iomem *) physaddr; 132 #endif 133 134 #ifdef DEBUG 135 printk("ioremap: 0x%lx,0x%lx(%d) - ", physaddr, size, cacheflag); 136 #endif 137 /* 138 * Mappings have to be aligned 139 */ 140 offset = physaddr & (IO_SIZE - 1); 141 physaddr &= -IO_SIZE; 142 size = (size + offset + IO_SIZE - 1) & -IO_SIZE; 143 144 /* 145 * Ok, go for it.. 146 */ 147 area = get_io_area(size); 148 if (!area) 149 return NULL; 150 151 virtaddr = (unsigned long)area->addr; 152 retaddr = virtaddr + offset; 153 #ifdef DEBUG 154 printk("0x%lx,0x%lx,0x%lx", physaddr, virtaddr, retaddr); 155 #endif 156 157 /* 158 * add cache and table flags to physical address 159 */ 160 if (CPU_IS_040_OR_060) { 161 physaddr |= (_PAGE_PRESENT | _PAGE_GLOBAL040 | 162 _PAGE_ACCESSED | _PAGE_DIRTY); 163 switch (cacheflag) { 164 case IOMAP_FULL_CACHING: 165 physaddr |= _PAGE_CACHE040; 166 break; 167 case IOMAP_NOCACHE_SER: 168 default: 169 physaddr |= _PAGE_NOCACHE_S; 170 break; 171 case IOMAP_NOCACHE_NONSER: 172 physaddr |= _PAGE_NOCACHE; 173 break; 174 case IOMAP_WRITETHROUGH: 175 physaddr |= _PAGE_CACHE040W; 176 break; 177 } 178 } else { 179 physaddr |= (_PAGE_PRESENT | _PAGE_ACCESSED | 180 _PAGE_DIRTY | _PAGE_READWRITE); 181 switch (cacheflag) { 182 case IOMAP_NOCACHE_SER: 183 case IOMAP_NOCACHE_NONSER: 184 default: 185 physaddr |= _PAGE_NOCACHE030; 186 break; 187 case IOMAP_FULL_CACHING: 188 case IOMAP_WRITETHROUGH: 189 break; 190 } 191 } 192 193 while ((long)size > 0) { 194 #ifdef DEBUG 195 if (!(virtaddr & (PTRTREESIZE-1))) 196 printk ("\npa=%#lx va=%#lx ", physaddr, virtaddr); 197 #endif 198 pgd_dir = pgd_offset_k(virtaddr); 199 pmd_dir = pmd_alloc(&init_mm, pgd_dir, virtaddr); 200 if (!pmd_dir) { 201 printk("ioremap: no mem for pmd_dir\n"); 202 return NULL; 203 } 204 205 if (CPU_IS_020_OR_030) { 206 pmd_dir->pmd[(virtaddr/PTRTREESIZE) & 15] = physaddr; 207 physaddr += PTRTREESIZE; 208 virtaddr += PTRTREESIZE; 209 size -= PTRTREESIZE; 210 } else { 211 pte_dir = pte_alloc_kernel(pmd_dir, virtaddr); 212 if (!pte_dir) { 213 printk("ioremap: no mem for pte_dir\n"); 214 return NULL; 215 } 216 217 pte_val(*pte_dir) = physaddr; 218 virtaddr += PAGE_SIZE; 219 physaddr += PAGE_SIZE; 220 size -= PAGE_SIZE; 221 } 222 } 223 #ifdef DEBUG 224 printk("\n"); 225 #endif 226 flush_tlb_all(); 227 228 return (void __iomem *)retaddr; 229 } 230 EXPORT_SYMBOL(__ioremap); 231 232 /* 233 * Unmap an ioremap()ed region again 234 */ 235 void iounmap(void __iomem *addr) 236 { 237 #ifdef CONFIG_AMIGA 238 if ((!MACH_IS_AMIGA) || 239 (((unsigned long)addr < 0x40000000) || 240 ((unsigned long)addr > 0x60000000))) 241 free_io_area((__force void *)addr); 242 #else 243 #ifdef CONFIG_COLDFIRE 244 if (cf_internalio(addr)) 245 return; 246 #endif 247 free_io_area((__force void *)addr); 248 #endif 249 } 250 EXPORT_SYMBOL(iounmap); 251 252 /* 253 * __iounmap unmaps nearly everything, so be careful 254 * Currently it doesn't free pointer/page tables anymore but this 255 * wasn't used anyway and might be added later. 256 */ 257 void __iounmap(void *addr, unsigned long size) 258 { 259 unsigned long virtaddr = (unsigned long)addr; 260 pgd_t *pgd_dir; 261 pmd_t *pmd_dir; 262 pte_t *pte_dir; 263 264 while ((long)size > 0) { 265 pgd_dir = pgd_offset_k(virtaddr); 266 if (pgd_bad(*pgd_dir)) { 267 printk("iounmap: bad pgd(%08lx)\n", pgd_val(*pgd_dir)); 268 pgd_clear(pgd_dir); 269 return; 270 } 271 pmd_dir = pmd_offset(pgd_dir, virtaddr); 272 273 if (CPU_IS_020_OR_030) { 274 int pmd_off = (virtaddr/PTRTREESIZE) & 15; 275 int pmd_type = pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK; 276 277 if (pmd_type == _PAGE_PRESENT) { 278 pmd_dir->pmd[pmd_off] = 0; 279 virtaddr += PTRTREESIZE; 280 size -= PTRTREESIZE; 281 continue; 282 } else if (pmd_type == 0) 283 continue; 284 } 285 286 if (pmd_bad(*pmd_dir)) { 287 printk("iounmap: bad pmd (%08lx)\n", pmd_val(*pmd_dir)); 288 pmd_clear(pmd_dir); 289 return; 290 } 291 pte_dir = pte_offset_kernel(pmd_dir, virtaddr); 292 293 pte_val(*pte_dir) = 0; 294 virtaddr += PAGE_SIZE; 295 size -= PAGE_SIZE; 296 } 297 298 flush_tlb_all(); 299 } 300 301 /* 302 * Set new cache mode for some kernel address space. 303 * The caller must push data for that range itself, if such data may already 304 * be in the cache. 305 */ 306 void kernel_set_cachemode(void *addr, unsigned long size, int cmode) 307 { 308 unsigned long virtaddr = (unsigned long)addr; 309 pgd_t *pgd_dir; 310 pmd_t *pmd_dir; 311 pte_t *pte_dir; 312 313 if (CPU_IS_040_OR_060) { 314 switch (cmode) { 315 case IOMAP_FULL_CACHING: 316 cmode = _PAGE_CACHE040; 317 break; 318 case IOMAP_NOCACHE_SER: 319 default: 320 cmode = _PAGE_NOCACHE_S; 321 break; 322 case IOMAP_NOCACHE_NONSER: 323 cmode = _PAGE_NOCACHE; 324 break; 325 case IOMAP_WRITETHROUGH: 326 cmode = _PAGE_CACHE040W; 327 break; 328 } 329 } else { 330 switch (cmode) { 331 case IOMAP_NOCACHE_SER: 332 case IOMAP_NOCACHE_NONSER: 333 default: 334 cmode = _PAGE_NOCACHE030; 335 break; 336 case IOMAP_FULL_CACHING: 337 case IOMAP_WRITETHROUGH: 338 cmode = 0; 339 } 340 } 341 342 while ((long)size > 0) { 343 pgd_dir = pgd_offset_k(virtaddr); 344 if (pgd_bad(*pgd_dir)) { 345 printk("iocachemode: bad pgd(%08lx)\n", pgd_val(*pgd_dir)); 346 pgd_clear(pgd_dir); 347 return; 348 } 349 pmd_dir = pmd_offset(pgd_dir, virtaddr); 350 351 if (CPU_IS_020_OR_030) { 352 int pmd_off = (virtaddr/PTRTREESIZE) & 15; 353 354 if ((pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK) == _PAGE_PRESENT) { 355 pmd_dir->pmd[pmd_off] = (pmd_dir->pmd[pmd_off] & 356 _CACHEMASK040) | cmode; 357 virtaddr += PTRTREESIZE; 358 size -= PTRTREESIZE; 359 continue; 360 } 361 } 362 363 if (pmd_bad(*pmd_dir)) { 364 printk("iocachemode: bad pmd (%08lx)\n", pmd_val(*pmd_dir)); 365 pmd_clear(pmd_dir); 366 return; 367 } 368 pte_dir = pte_offset_kernel(pmd_dir, virtaddr); 369 370 pte_val(*pte_dir) = (pte_val(*pte_dir) & _CACHEMASK040) | cmode; 371 virtaddr += PAGE_SIZE; 372 size -= PAGE_SIZE; 373 } 374 375 flush_tlb_all(); 376 } 377 EXPORT_SYMBOL(kernel_set_cachemode); 378