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 __iounmap(tmp->addr, tmp->size); 93 kfree(tmp); 94 return; 95 } 96 } 97 } 98 99 #endif 100 101 /* 102 * Map some physical address range into the kernel address space. 103 */ 104 /* Rewritten by Andreas Schwab to remove all races. */ 105 106 void __iomem *__ioremap(unsigned long physaddr, unsigned long size, int cacheflag) 107 { 108 struct vm_struct *area; 109 unsigned long virtaddr, retaddr; 110 long offset; 111 pgd_t *pgd_dir; 112 pmd_t *pmd_dir; 113 pte_t *pte_dir; 114 115 /* 116 * Don't allow mappings that wrap.. 117 */ 118 if (!size || physaddr > (unsigned long)(-size)) 119 return NULL; 120 121 #ifdef CONFIG_AMIGA 122 if (MACH_IS_AMIGA) { 123 if ((physaddr >= 0x40000000) && (physaddr + size < 0x60000000) 124 && (cacheflag == IOMAP_NOCACHE_SER)) 125 return (void __iomem *)physaddr; 126 } 127 #endif 128 129 #ifdef DEBUG 130 printk("ioremap: 0x%lx,0x%lx(%d) - ", physaddr, size, cacheflag); 131 #endif 132 /* 133 * Mappings have to be aligned 134 */ 135 offset = physaddr & (IO_SIZE - 1); 136 physaddr &= -IO_SIZE; 137 size = (size + offset + IO_SIZE - 1) & -IO_SIZE; 138 139 /* 140 * Ok, go for it.. 141 */ 142 area = get_io_area(size); 143 if (!area) 144 return NULL; 145 146 virtaddr = (unsigned long)area->addr; 147 retaddr = virtaddr + offset; 148 #ifdef DEBUG 149 printk("0x%lx,0x%lx,0x%lx", physaddr, virtaddr, retaddr); 150 #endif 151 152 /* 153 * add cache and table flags to physical address 154 */ 155 if (CPU_IS_040_OR_060) { 156 physaddr |= (_PAGE_PRESENT | _PAGE_GLOBAL040 | 157 _PAGE_ACCESSED | _PAGE_DIRTY); 158 switch (cacheflag) { 159 case IOMAP_FULL_CACHING: 160 physaddr |= _PAGE_CACHE040; 161 break; 162 case IOMAP_NOCACHE_SER: 163 default: 164 physaddr |= _PAGE_NOCACHE_S; 165 break; 166 case IOMAP_NOCACHE_NONSER: 167 physaddr |= _PAGE_NOCACHE; 168 break; 169 case IOMAP_WRITETHROUGH: 170 physaddr |= _PAGE_CACHE040W; 171 break; 172 } 173 } else { 174 physaddr |= (_PAGE_PRESENT | _PAGE_ACCESSED | 175 _PAGE_DIRTY | _PAGE_READWRITE); 176 switch (cacheflag) { 177 case IOMAP_NOCACHE_SER: 178 case IOMAP_NOCACHE_NONSER: 179 default: 180 physaddr |= _PAGE_NOCACHE030; 181 break; 182 case IOMAP_FULL_CACHING: 183 case IOMAP_WRITETHROUGH: 184 break; 185 } 186 } 187 188 while ((long)size > 0) { 189 #ifdef DEBUG 190 if (!(virtaddr & (PTRTREESIZE-1))) 191 printk ("\npa=%#lx va=%#lx ", physaddr, virtaddr); 192 #endif 193 pgd_dir = pgd_offset_k(virtaddr); 194 pmd_dir = pmd_alloc(&init_mm, pgd_dir, virtaddr); 195 if (!pmd_dir) { 196 printk("ioremap: no mem for pmd_dir\n"); 197 return NULL; 198 } 199 200 if (CPU_IS_020_OR_030) { 201 pmd_dir->pmd[(virtaddr/PTRTREESIZE) & 15] = physaddr; 202 physaddr += PTRTREESIZE; 203 virtaddr += PTRTREESIZE; 204 size -= PTRTREESIZE; 205 } else { 206 pte_dir = pte_alloc_kernel(pmd_dir, virtaddr); 207 if (!pte_dir) { 208 printk("ioremap: no mem for pte_dir\n"); 209 return NULL; 210 } 211 212 pte_val(*pte_dir) = physaddr; 213 virtaddr += PAGE_SIZE; 214 physaddr += PAGE_SIZE; 215 size -= PAGE_SIZE; 216 } 217 } 218 #ifdef DEBUG 219 printk("\n"); 220 #endif 221 flush_tlb_all(); 222 223 return (void __iomem *)retaddr; 224 } 225 EXPORT_SYMBOL(__ioremap); 226 227 /* 228 * Unmap an ioremap()ed region again 229 */ 230 void iounmap(void __iomem *addr) 231 { 232 #ifdef CONFIG_AMIGA 233 if ((!MACH_IS_AMIGA) || 234 (((unsigned long)addr < 0x40000000) || 235 ((unsigned long)addr > 0x60000000))) 236 free_io_area((__force void *)addr); 237 #else 238 free_io_area((__force void *)addr); 239 #endif 240 } 241 EXPORT_SYMBOL(iounmap); 242 243 /* 244 * __iounmap unmaps nearly everything, so be careful 245 * Currently it doesn't free pointer/page tables anymore but this 246 * wasn't used anyway and might be added later. 247 */ 248 void __iounmap(void *addr, unsigned long size) 249 { 250 unsigned long virtaddr = (unsigned long)addr; 251 pgd_t *pgd_dir; 252 pmd_t *pmd_dir; 253 pte_t *pte_dir; 254 255 while ((long)size > 0) { 256 pgd_dir = pgd_offset_k(virtaddr); 257 if (pgd_bad(*pgd_dir)) { 258 printk("iounmap: bad pgd(%08lx)\n", pgd_val(*pgd_dir)); 259 pgd_clear(pgd_dir); 260 return; 261 } 262 pmd_dir = pmd_offset(pgd_dir, virtaddr); 263 264 if (CPU_IS_020_OR_030) { 265 int pmd_off = (virtaddr/PTRTREESIZE) & 15; 266 int pmd_type = pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK; 267 268 if (pmd_type == _PAGE_PRESENT) { 269 pmd_dir->pmd[pmd_off] = 0; 270 virtaddr += PTRTREESIZE; 271 size -= PTRTREESIZE; 272 continue; 273 } else if (pmd_type == 0) 274 continue; 275 } 276 277 if (pmd_bad(*pmd_dir)) { 278 printk("iounmap: bad pmd (%08lx)\n", pmd_val(*pmd_dir)); 279 pmd_clear(pmd_dir); 280 return; 281 } 282 pte_dir = pte_offset_kernel(pmd_dir, virtaddr); 283 284 pte_val(*pte_dir) = 0; 285 virtaddr += PAGE_SIZE; 286 size -= PAGE_SIZE; 287 } 288 289 flush_tlb_all(); 290 } 291 292 /* 293 * Set new cache mode for some kernel address space. 294 * The caller must push data for that range itself, if such data may already 295 * be in the cache. 296 */ 297 void kernel_set_cachemode(void *addr, unsigned long size, int cmode) 298 { 299 unsigned long virtaddr = (unsigned long)addr; 300 pgd_t *pgd_dir; 301 pmd_t *pmd_dir; 302 pte_t *pte_dir; 303 304 if (CPU_IS_040_OR_060) { 305 switch (cmode) { 306 case IOMAP_FULL_CACHING: 307 cmode = _PAGE_CACHE040; 308 break; 309 case IOMAP_NOCACHE_SER: 310 default: 311 cmode = _PAGE_NOCACHE_S; 312 break; 313 case IOMAP_NOCACHE_NONSER: 314 cmode = _PAGE_NOCACHE; 315 break; 316 case IOMAP_WRITETHROUGH: 317 cmode = _PAGE_CACHE040W; 318 break; 319 } 320 } else { 321 switch (cmode) { 322 case IOMAP_NOCACHE_SER: 323 case IOMAP_NOCACHE_NONSER: 324 default: 325 cmode = _PAGE_NOCACHE030; 326 break; 327 case IOMAP_FULL_CACHING: 328 case IOMAP_WRITETHROUGH: 329 cmode = 0; 330 } 331 } 332 333 while ((long)size > 0) { 334 pgd_dir = pgd_offset_k(virtaddr); 335 if (pgd_bad(*pgd_dir)) { 336 printk("iocachemode: bad pgd(%08lx)\n", pgd_val(*pgd_dir)); 337 pgd_clear(pgd_dir); 338 return; 339 } 340 pmd_dir = pmd_offset(pgd_dir, virtaddr); 341 342 if (CPU_IS_020_OR_030) { 343 int pmd_off = (virtaddr/PTRTREESIZE) & 15; 344 345 if ((pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK) == _PAGE_PRESENT) { 346 pmd_dir->pmd[pmd_off] = (pmd_dir->pmd[pmd_off] & 347 _CACHEMASK040) | cmode; 348 virtaddr += PTRTREESIZE; 349 size -= PTRTREESIZE; 350 continue; 351 } 352 } 353 354 if (pmd_bad(*pmd_dir)) { 355 printk("iocachemode: bad pmd (%08lx)\n", pmd_val(*pmd_dir)); 356 pmd_clear(pmd_dir); 357 return; 358 } 359 pte_dir = pte_offset_kernel(pmd_dir, virtaddr); 360 361 pte_val(*pte_dir) = (pte_val(*pte_dir) & _CACHEMASK040) | cmode; 362 virtaddr += PAGE_SIZE; 363 size -= PAGE_SIZE; 364 } 365 366 flush_tlb_all(); 367 } 368 EXPORT_SYMBOL(kernel_set_cachemode); 369