1 /* 2 * This file is subject to the terms and conditions of the GNU General Public 3 * License. See the file "COPYING" in the main directory of this archive 4 * for more details. 5 * 6 * Copyright (C) 1994 - 2000 Ralf Baechle 7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc. 8 * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com 9 * Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved. 10 */ 11 #include <linux/bug.h> 12 #include <linux/init.h> 13 #include <linux/module.h> 14 #include <linux/signal.h> 15 #include <linux/sched.h> 16 #include <linux/smp.h> 17 #include <linux/kernel.h> 18 #include <linux/errno.h> 19 #include <linux/string.h> 20 #include <linux/types.h> 21 #include <linux/pagemap.h> 22 #include <linux/ptrace.h> 23 #include <linux/mman.h> 24 #include <linux/mm.h> 25 #include <linux/bootmem.h> 26 #include <linux/highmem.h> 27 #include <linux/swap.h> 28 #include <linux/proc_fs.h> 29 #include <linux/pfn.h> 30 #include <linux/hardirq.h> 31 #include <linux/gfp.h> 32 #include <linux/kcore.h> 33 34 #include <asm/asm-offsets.h> 35 #include <asm/bootinfo.h> 36 #include <asm/cachectl.h> 37 #include <asm/cpu.h> 38 #include <asm/dma.h> 39 #include <asm/kmap_types.h> 40 #include <asm/mmu_context.h> 41 #include <asm/sections.h> 42 #include <asm/pgtable.h> 43 #include <asm/pgalloc.h> 44 #include <asm/tlb.h> 45 #include <asm/fixmap.h> 46 47 /* 48 * We have up to 8 empty zeroed pages so we can map one of the right colour 49 * when needed. This is necessary only on R4000 / R4400 SC and MC versions 50 * where we have to avoid VCED / VECI exceptions for good performance at 51 * any price. Since page is never written to after the initialization we 52 * don't have to care about aliases on other CPUs. 53 */ 54 unsigned long empty_zero_page, zero_page_mask; 55 EXPORT_SYMBOL_GPL(empty_zero_page); 56 EXPORT_SYMBOL(zero_page_mask); 57 58 /* 59 * Not static inline because used by IP27 special magic initialization code 60 */ 61 void setup_zero_pages(void) 62 { 63 unsigned int order, i; 64 struct page *page; 65 66 if (cpu_has_vce) 67 order = 3; 68 else 69 order = 0; 70 71 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 72 if (!empty_zero_page) 73 panic("Oh boy, that early out of memory?"); 74 75 page = virt_to_page((void *)empty_zero_page); 76 split_page(page, order); 77 for (i = 0; i < (1 << order); i++, page++) 78 mark_page_reserved(page); 79 80 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; 81 } 82 83 static void *__kmap_pgprot(struct page *page, unsigned long addr, pgprot_t prot) 84 { 85 enum fixed_addresses idx; 86 unsigned long vaddr, flags, entrylo; 87 unsigned long old_ctx; 88 pte_t pte; 89 int tlbidx; 90 91 BUG_ON(Page_dcache_dirty(page)); 92 93 pagefault_disable(); 94 idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1); 95 idx += in_interrupt() ? FIX_N_COLOURS : 0; 96 vaddr = __fix_to_virt(FIX_CMAP_END - idx); 97 pte = mk_pte(page, prot); 98 #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) 99 entrylo = pte_to_entrylo(pte.pte_high); 100 #else 101 entrylo = pte_to_entrylo(pte_val(pte)); 102 #endif 103 104 local_irq_save(flags); 105 old_ctx = read_c0_entryhi(); 106 write_c0_entryhi(vaddr & (PAGE_MASK << 1)); 107 write_c0_entrylo0(entrylo); 108 write_c0_entrylo1(entrylo); 109 #ifdef CONFIG_XPA 110 entrylo = (pte.pte_low & _PFNX_MASK); 111 writex_c0_entrylo0(entrylo); 112 writex_c0_entrylo1(entrylo); 113 #endif 114 tlbidx = read_c0_wired(); 115 write_c0_wired(tlbidx + 1); 116 write_c0_index(tlbidx); 117 mtc0_tlbw_hazard(); 118 tlb_write_indexed(); 119 tlbw_use_hazard(); 120 write_c0_entryhi(old_ctx); 121 local_irq_restore(flags); 122 123 return (void*) vaddr; 124 } 125 126 void *kmap_coherent(struct page *page, unsigned long addr) 127 { 128 return __kmap_pgprot(page, addr, PAGE_KERNEL); 129 } 130 131 void *kmap_noncoherent(struct page *page, unsigned long addr) 132 { 133 return __kmap_pgprot(page, addr, PAGE_KERNEL_NC); 134 } 135 136 void kunmap_coherent(void) 137 { 138 unsigned int wired; 139 unsigned long flags, old_ctx; 140 141 local_irq_save(flags); 142 old_ctx = read_c0_entryhi(); 143 wired = read_c0_wired() - 1; 144 write_c0_wired(wired); 145 write_c0_index(wired); 146 write_c0_entryhi(UNIQUE_ENTRYHI(wired)); 147 write_c0_entrylo0(0); 148 write_c0_entrylo1(0); 149 mtc0_tlbw_hazard(); 150 tlb_write_indexed(); 151 tlbw_use_hazard(); 152 write_c0_entryhi(old_ctx); 153 local_irq_restore(flags); 154 pagefault_enable(); 155 } 156 157 void copy_user_highpage(struct page *to, struct page *from, 158 unsigned long vaddr, struct vm_area_struct *vma) 159 { 160 void *vfrom, *vto; 161 162 vto = kmap_atomic(to); 163 if (cpu_has_dc_aliases && 164 page_mapped(from) && !Page_dcache_dirty(from)) { 165 vfrom = kmap_coherent(from, vaddr); 166 copy_page(vto, vfrom); 167 kunmap_coherent(); 168 } else { 169 vfrom = kmap_atomic(from); 170 copy_page(vto, vfrom); 171 kunmap_atomic(vfrom); 172 } 173 if ((!cpu_has_ic_fills_f_dc) || 174 pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK)) 175 flush_data_cache_page((unsigned long)vto); 176 kunmap_atomic(vto); 177 /* Make sure this page is cleared on other CPU's too before using it */ 178 smp_wmb(); 179 } 180 181 void copy_to_user_page(struct vm_area_struct *vma, 182 struct page *page, unsigned long vaddr, void *dst, const void *src, 183 unsigned long len) 184 { 185 if (cpu_has_dc_aliases && 186 page_mapped(page) && !Page_dcache_dirty(page)) { 187 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 188 memcpy(vto, src, len); 189 kunmap_coherent(); 190 } else { 191 memcpy(dst, src, len); 192 if (cpu_has_dc_aliases) 193 SetPageDcacheDirty(page); 194 } 195 if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc) 196 flush_cache_page(vma, vaddr, page_to_pfn(page)); 197 } 198 199 void copy_from_user_page(struct vm_area_struct *vma, 200 struct page *page, unsigned long vaddr, void *dst, const void *src, 201 unsigned long len) 202 { 203 if (cpu_has_dc_aliases && 204 page_mapped(page) && !Page_dcache_dirty(page)) { 205 void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 206 memcpy(dst, vfrom, len); 207 kunmap_coherent(); 208 } else { 209 memcpy(dst, src, len); 210 if (cpu_has_dc_aliases) 211 SetPageDcacheDirty(page); 212 } 213 } 214 EXPORT_SYMBOL_GPL(copy_from_user_page); 215 216 void __init fixrange_init(unsigned long start, unsigned long end, 217 pgd_t *pgd_base) 218 { 219 #ifdef CONFIG_HIGHMEM 220 pgd_t *pgd; 221 pud_t *pud; 222 pmd_t *pmd; 223 pte_t *pte; 224 int i, j, k; 225 unsigned long vaddr; 226 227 vaddr = start; 228 i = __pgd_offset(vaddr); 229 j = __pud_offset(vaddr); 230 k = __pmd_offset(vaddr); 231 pgd = pgd_base + i; 232 233 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) { 234 pud = (pud_t *)pgd; 235 for ( ; (j < PTRS_PER_PUD) && (vaddr < end); pud++, j++) { 236 pmd = (pmd_t *)pud; 237 for (; (k < PTRS_PER_PMD) && (vaddr < end); pmd++, k++) { 238 if (pmd_none(*pmd)) { 239 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); 240 set_pmd(pmd, __pmd((unsigned long)pte)); 241 BUG_ON(pte != pte_offset_kernel(pmd, 0)); 242 } 243 vaddr += PMD_SIZE; 244 } 245 k = 0; 246 } 247 j = 0; 248 } 249 #endif 250 } 251 252 #ifndef CONFIG_NEED_MULTIPLE_NODES 253 int page_is_ram(unsigned long pagenr) 254 { 255 int i; 256 257 for (i = 0; i < boot_mem_map.nr_map; i++) { 258 unsigned long addr, end; 259 260 switch (boot_mem_map.map[i].type) { 261 case BOOT_MEM_RAM: 262 case BOOT_MEM_INIT_RAM: 263 break; 264 default: 265 /* not usable memory */ 266 continue; 267 } 268 269 addr = PFN_UP(boot_mem_map.map[i].addr); 270 end = PFN_DOWN(boot_mem_map.map[i].addr + 271 boot_mem_map.map[i].size); 272 273 if (pagenr >= addr && pagenr < end) 274 return 1; 275 } 276 277 return 0; 278 } 279 280 void __init paging_init(void) 281 { 282 unsigned long max_zone_pfns[MAX_NR_ZONES]; 283 unsigned long lastpfn __maybe_unused; 284 285 pagetable_init(); 286 287 #ifdef CONFIG_HIGHMEM 288 kmap_init(); 289 #endif 290 #ifdef CONFIG_ZONE_DMA 291 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN; 292 #endif 293 #ifdef CONFIG_ZONE_DMA32 294 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN; 295 #endif 296 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 297 lastpfn = max_low_pfn; 298 #ifdef CONFIG_HIGHMEM 299 max_zone_pfns[ZONE_HIGHMEM] = highend_pfn; 300 lastpfn = highend_pfn; 301 302 if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) { 303 printk(KERN_WARNING "This processor doesn't support highmem." 304 " %ldk highmem ignored\n", 305 (highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10)); 306 max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn; 307 lastpfn = max_low_pfn; 308 } 309 #endif 310 311 free_area_init_nodes(max_zone_pfns); 312 } 313 314 #ifdef CONFIG_64BIT 315 static struct kcore_list kcore_kseg0; 316 #endif 317 318 static inline void mem_init_free_highmem(void) 319 { 320 #ifdef CONFIG_HIGHMEM 321 unsigned long tmp; 322 323 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) { 324 struct page *page = pfn_to_page(tmp); 325 326 if (!page_is_ram(tmp)) 327 SetPageReserved(page); 328 else 329 free_highmem_page(page); 330 } 331 #endif 332 } 333 334 unsigned __weak platform_maar_init(unsigned num_maars) 335 { 336 return 0; 337 } 338 339 static void maar_init(void) 340 { 341 unsigned num_maars, used, i; 342 343 if (!cpu_has_maar) 344 return; 345 346 /* Detect the number of MAARs */ 347 write_c0_maari(~0); 348 back_to_back_c0_hazard(); 349 num_maars = read_c0_maari() + 1; 350 351 /* MAARs should be in pairs */ 352 WARN_ON(num_maars % 2); 353 354 /* Configure the required MAARs */ 355 used = platform_maar_init(num_maars / 2); 356 357 /* Disable any further MAARs */ 358 for (i = (used * 2); i < num_maars; i++) { 359 write_c0_maari(i); 360 back_to_back_c0_hazard(); 361 write_c0_maar(0); 362 back_to_back_c0_hazard(); 363 } 364 } 365 366 void __init mem_init(void) 367 { 368 #ifdef CONFIG_HIGHMEM 369 #ifdef CONFIG_DISCONTIGMEM 370 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet" 371 #endif 372 max_mapnr = highend_pfn ? highend_pfn : max_low_pfn; 373 #else 374 max_mapnr = max_low_pfn; 375 #endif 376 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); 377 378 maar_init(); 379 free_all_bootmem(); 380 setup_zero_pages(); /* Setup zeroed pages. */ 381 mem_init_free_highmem(); 382 mem_init_print_info(NULL); 383 384 #ifdef CONFIG_64BIT 385 if ((unsigned long) &_text > (unsigned long) CKSEG0) 386 /* The -4 is a hack so that user tools don't have to handle 387 the overflow. */ 388 kclist_add(&kcore_kseg0, (void *) CKSEG0, 389 0x80000000 - 4, KCORE_TEXT); 390 #endif 391 } 392 #endif /* !CONFIG_NEED_MULTIPLE_NODES */ 393 394 void free_init_pages(const char *what, unsigned long begin, unsigned long end) 395 { 396 unsigned long pfn; 397 398 for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) { 399 struct page *page = pfn_to_page(pfn); 400 void *addr = phys_to_virt(PFN_PHYS(pfn)); 401 402 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE); 403 free_reserved_page(page); 404 } 405 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 406 } 407 408 #ifdef CONFIG_BLK_DEV_INITRD 409 void free_initrd_mem(unsigned long start, unsigned long end) 410 { 411 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM, 412 "initrd"); 413 } 414 #endif 415 416 void (*free_init_pages_eva)(void *begin, void *end) = NULL; 417 418 void __init_refok free_initmem(void) 419 { 420 prom_free_prom_memory(); 421 /* 422 * Let the platform define a specific function to free the 423 * init section since EVA may have used any possible mapping 424 * between virtual and physical addresses. 425 */ 426 if (free_init_pages_eva) 427 free_init_pages_eva((void *)&__init_begin, (void *)&__init_end); 428 else 429 free_initmem_default(POISON_FREE_INITMEM); 430 } 431 432 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT 433 unsigned long pgd_current[NR_CPUS]; 434 #endif 435 436 /* 437 * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER 438 * are constants. So we use the variants from asm-offset.h until that gcc 439 * will officially be retired. 440 * 441 * Align swapper_pg_dir in to 64K, allows its address to be loaded 442 * with a single LUI instruction in the TLB handlers. If we used 443 * __aligned(64K), its size would get rounded up to the alignment 444 * size, and waste space. So we place it in its own section and align 445 * it in the linker script. 446 */ 447 pgd_t swapper_pg_dir[_PTRS_PER_PGD] __section(.bss..swapper_pg_dir); 448 #ifndef __PAGETABLE_PMD_FOLDED 449 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned_bss; 450 #endif 451 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss; 452