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/page.h> 21 #include <asm/io.h> 22 #include <asm/tlbflush.h> 23 24 #undef DEBUG 25 26 /* 27 * For 040/060 we can use the virtual memory area like other architectures, 28 * but for 020/030 we want to use early termination page descriptors and we 29 * can't mix this with normal page descriptors, so we have to copy that code 30 * (mm/vmalloc.c) and return appropriately aligned addresses. 31 */ 32 33 #ifdef CPU_M68040_OR_M68060_ONLY 34 35 #define IO_SIZE PAGE_SIZE 36 37 static inline struct vm_struct *get_io_area(unsigned long size) 38 { 39 return get_vm_area(size, VM_IOREMAP); 40 } 41 42 43 static inline void free_io_area(void *addr) 44 { 45 vfree((void *)(PAGE_MASK & (unsigned long)addr)); 46 } 47 48 #else 49 50 #define IO_SIZE PMD_SIZE 51 52 static struct vm_struct *iolist; 53 54 /* 55 * __free_io_area unmaps nearly everything, so be careful 56 * Currently it doesn't free pointer/page tables anymore but this 57 * wasn't used anyway and might be added later. 58 */ 59 static void __free_io_area(void *addr, unsigned long size) 60 { 61 unsigned long virtaddr = (unsigned long)addr; 62 pgd_t *pgd_dir; 63 p4d_t *p4d_dir; 64 pud_t *pud_dir; 65 pmd_t *pmd_dir; 66 pte_t *pte_dir; 67 68 while ((long)size > 0) { 69 pgd_dir = pgd_offset_k(virtaddr); 70 p4d_dir = p4d_offset(pgd_dir, virtaddr); 71 pud_dir = pud_offset(p4d_dir, virtaddr); 72 if (pud_bad(*pud_dir)) { 73 printk("iounmap: bad pud(%08lx)\n", pud_val(*pud_dir)); 74 pud_clear(pud_dir); 75 return; 76 } 77 pmd_dir = pmd_offset(pud_dir, virtaddr); 78 79 #if CONFIG_PGTABLE_LEVELS == 3 80 if (CPU_IS_020_OR_030) { 81 int pmd_type = pmd_val(*pmd_dir) & _DESCTYPE_MASK; 82 83 if (pmd_type == _PAGE_PRESENT) { 84 pmd_clear(pmd_dir); 85 virtaddr += PMD_SIZE; 86 size -= PMD_SIZE; 87 88 } else if (pmd_type == 0) 89 continue; 90 } 91 #endif 92 93 if (pmd_bad(*pmd_dir)) { 94 printk("iounmap: bad pmd (%08lx)\n", pmd_val(*pmd_dir)); 95 pmd_clear(pmd_dir); 96 return; 97 } 98 pte_dir = pte_offset_kernel(pmd_dir, virtaddr); 99 100 pte_val(*pte_dir) = 0; 101 virtaddr += PAGE_SIZE; 102 size -= PAGE_SIZE; 103 } 104 105 flush_tlb_all(); 106 } 107 108 static struct vm_struct *get_io_area(unsigned long size) 109 { 110 unsigned long addr; 111 struct vm_struct **p, *tmp, *area; 112 113 area = kmalloc(sizeof(*area), GFP_KERNEL); 114 if (!area) 115 return NULL; 116 addr = KMAP_START; 117 for (p = &iolist; (tmp = *p) ; p = &tmp->next) { 118 if (size + addr < (unsigned long)tmp->addr) 119 break; 120 if (addr > KMAP_END-size) { 121 kfree(area); 122 return NULL; 123 } 124 addr = tmp->size + (unsigned long)tmp->addr; 125 } 126 area->addr = (void *)addr; 127 area->size = size + IO_SIZE; 128 area->next = *p; 129 *p = area; 130 return area; 131 } 132 133 static inline void free_io_area(void *addr) 134 { 135 struct vm_struct **p, *tmp; 136 137 if (!addr) 138 return; 139 addr = (void *)((unsigned long)addr & -IO_SIZE); 140 for (p = &iolist ; (tmp = *p) ; p = &tmp->next) { 141 if (tmp->addr == addr) { 142 *p = tmp->next; 143 /* remove gap added in get_io_area() */ 144 __free_io_area(tmp->addr, tmp->size - IO_SIZE); 145 kfree(tmp); 146 return; 147 } 148 } 149 } 150 151 #endif 152 153 /* 154 * Map some physical address range into the kernel address space. 155 */ 156 /* Rewritten by Andreas Schwab to remove all races. */ 157 158 void __iomem *__ioremap(unsigned long physaddr, unsigned long size, int cacheflag) 159 { 160 struct vm_struct *area; 161 unsigned long virtaddr, retaddr; 162 long offset; 163 pgd_t *pgd_dir; 164 p4d_t *p4d_dir; 165 pud_t *pud_dir; 166 pmd_t *pmd_dir; 167 pte_t *pte_dir; 168 169 /* 170 * Don't allow mappings that wrap.. 171 */ 172 if (!size || physaddr > (unsigned long)(-size)) 173 return NULL; 174 175 #ifdef CONFIG_AMIGA 176 if (MACH_IS_AMIGA) { 177 if ((physaddr >= 0x40000000) && (physaddr + size < 0x60000000) 178 && (cacheflag == IOMAP_NOCACHE_SER)) 179 return (void __iomem *)physaddr; 180 } 181 #endif 182 #ifdef CONFIG_COLDFIRE 183 if (__cf_internalio(physaddr)) 184 return (void __iomem *) physaddr; 185 #endif 186 187 #ifdef DEBUG 188 printk("ioremap: 0x%lx,0x%lx(%d) - ", physaddr, size, cacheflag); 189 #endif 190 /* 191 * Mappings have to be aligned 192 */ 193 offset = physaddr & (IO_SIZE - 1); 194 physaddr &= -IO_SIZE; 195 size = (size + offset + IO_SIZE - 1) & -IO_SIZE; 196 197 /* 198 * Ok, go for it.. 199 */ 200 area = get_io_area(size); 201 if (!area) 202 return NULL; 203 204 virtaddr = (unsigned long)area->addr; 205 retaddr = virtaddr + offset; 206 #ifdef DEBUG 207 printk("0x%lx,0x%lx,0x%lx", physaddr, virtaddr, retaddr); 208 #endif 209 210 /* 211 * add cache and table flags to physical address 212 */ 213 if (CPU_IS_040_OR_060) { 214 physaddr |= (_PAGE_PRESENT | _PAGE_GLOBAL040 | 215 _PAGE_ACCESSED | _PAGE_DIRTY); 216 switch (cacheflag) { 217 case IOMAP_FULL_CACHING: 218 physaddr |= _PAGE_CACHE040; 219 break; 220 case IOMAP_NOCACHE_SER: 221 default: 222 physaddr |= _PAGE_NOCACHE_S; 223 break; 224 case IOMAP_NOCACHE_NONSER: 225 physaddr |= _PAGE_NOCACHE; 226 break; 227 case IOMAP_WRITETHROUGH: 228 physaddr |= _PAGE_CACHE040W; 229 break; 230 } 231 } else { 232 physaddr |= (_PAGE_PRESENT | _PAGE_ACCESSED | 233 _PAGE_DIRTY | _PAGE_READWRITE); 234 switch (cacheflag) { 235 case IOMAP_NOCACHE_SER: 236 case IOMAP_NOCACHE_NONSER: 237 default: 238 physaddr |= _PAGE_NOCACHE030; 239 break; 240 case IOMAP_FULL_CACHING: 241 case IOMAP_WRITETHROUGH: 242 break; 243 } 244 } 245 246 while ((long)size > 0) { 247 #ifdef DEBUG 248 if (!(virtaddr & (PMD_SIZE-1))) 249 printk ("\npa=%#lx va=%#lx ", physaddr, virtaddr); 250 #endif 251 pgd_dir = pgd_offset_k(virtaddr); 252 p4d_dir = p4d_offset(pgd_dir, virtaddr); 253 pud_dir = pud_offset(p4d_dir, virtaddr); 254 pmd_dir = pmd_alloc(&init_mm, pud_dir, virtaddr); 255 if (!pmd_dir) { 256 printk("ioremap: no mem for pmd_dir\n"); 257 return NULL; 258 } 259 260 #if CONFIG_PGTABLE_LEVELS == 3 261 if (CPU_IS_020_OR_030) { 262 pmd_val(*pmd_dir) = physaddr; 263 physaddr += PMD_SIZE; 264 virtaddr += PMD_SIZE; 265 size -= PMD_SIZE; 266 } else 267 #endif 268 { 269 pte_dir = pte_alloc_kernel(pmd_dir, virtaddr); 270 if (!pte_dir) { 271 printk("ioremap: no mem for pte_dir\n"); 272 return NULL; 273 } 274 275 pte_val(*pte_dir) = physaddr; 276 virtaddr += PAGE_SIZE; 277 physaddr += PAGE_SIZE; 278 size -= PAGE_SIZE; 279 } 280 } 281 #ifdef DEBUG 282 printk("\n"); 283 #endif 284 flush_tlb_all(); 285 286 return (void __iomem *)retaddr; 287 } 288 EXPORT_SYMBOL(__ioremap); 289 290 /* 291 * Unmap an ioremap()ed region again 292 */ 293 void iounmap(void __iomem *addr) 294 { 295 #ifdef CONFIG_AMIGA 296 if ((!MACH_IS_AMIGA) || 297 (((unsigned long)addr < 0x40000000) || 298 ((unsigned long)addr > 0x60000000))) 299 free_io_area((__force void *)addr); 300 #else 301 #ifdef CONFIG_COLDFIRE 302 if (cf_internalio(addr)) 303 return; 304 #endif 305 free_io_area((__force void *)addr); 306 #endif 307 } 308 EXPORT_SYMBOL(iounmap); 309 310 /* 311 * Set new cache mode for some kernel address space. 312 * The caller must push data for that range itself, if such data may already 313 * be in the cache. 314 */ 315 void kernel_set_cachemode(void *addr, unsigned long size, int cmode) 316 { 317 unsigned long virtaddr = (unsigned long)addr; 318 pgd_t *pgd_dir; 319 p4d_t *p4d_dir; 320 pud_t *pud_dir; 321 pmd_t *pmd_dir; 322 pte_t *pte_dir; 323 324 if (CPU_IS_040_OR_060) { 325 switch (cmode) { 326 case IOMAP_FULL_CACHING: 327 cmode = _PAGE_CACHE040; 328 break; 329 case IOMAP_NOCACHE_SER: 330 default: 331 cmode = _PAGE_NOCACHE_S; 332 break; 333 case IOMAP_NOCACHE_NONSER: 334 cmode = _PAGE_NOCACHE; 335 break; 336 case IOMAP_WRITETHROUGH: 337 cmode = _PAGE_CACHE040W; 338 break; 339 } 340 } else { 341 switch (cmode) { 342 case IOMAP_NOCACHE_SER: 343 case IOMAP_NOCACHE_NONSER: 344 default: 345 cmode = _PAGE_NOCACHE030; 346 break; 347 case IOMAP_FULL_CACHING: 348 case IOMAP_WRITETHROUGH: 349 cmode = 0; 350 } 351 } 352 353 while ((long)size > 0) { 354 pgd_dir = pgd_offset_k(virtaddr); 355 p4d_dir = p4d_offset(pgd_dir, virtaddr); 356 pud_dir = pud_offset(p4d_dir, virtaddr); 357 if (pud_bad(*pud_dir)) { 358 printk("iocachemode: bad pud(%08lx)\n", pud_val(*pud_dir)); 359 pud_clear(pud_dir); 360 return; 361 } 362 pmd_dir = pmd_offset(pud_dir, virtaddr); 363 364 #if CONFIG_PGTABLE_LEVELS == 3 365 if (CPU_IS_020_OR_030) { 366 unsigned long pmd = pmd_val(*pmd_dir); 367 368 if ((pmd & _DESCTYPE_MASK) == _PAGE_PRESENT) { 369 *pmd_dir = __pmd((pmd & _CACHEMASK040) | cmode); 370 virtaddr += PMD_SIZE; 371 size -= PMD_SIZE; 372 continue; 373 } 374 } 375 #endif 376 377 if (pmd_bad(*pmd_dir)) { 378 printk("iocachemode: bad pmd (%08lx)\n", pmd_val(*pmd_dir)); 379 pmd_clear(pmd_dir); 380 return; 381 } 382 pte_dir = pte_offset_kernel(pmd_dir, virtaddr); 383 384 pte_val(*pte_dir) = (pte_val(*pte_dir) & _CACHEMASK040) | cmode; 385 virtaddr += PAGE_SIZE; 386 size -= PAGE_SIZE; 387 } 388 389 flush_tlb_all(); 390 } 391 EXPORT_SYMBOL(kernel_set_cachemode); 392