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 /* Atomicity and interruptability */ 48 #ifdef CONFIG_MIPS_MT_SMTC 49 50 #include <asm/mipsmtregs.h> 51 52 #define ENTER_CRITICAL(flags) \ 53 { \ 54 unsigned int mvpflags; \ 55 local_irq_save(flags);\ 56 mvpflags = dvpe() 57 #define EXIT_CRITICAL(flags) \ 58 evpe(mvpflags); \ 59 local_irq_restore(flags); \ 60 } 61 #else 62 63 #define ENTER_CRITICAL(flags) local_irq_save(flags) 64 #define EXIT_CRITICAL(flags) local_irq_restore(flags) 65 66 #endif /* CONFIG_MIPS_MT_SMTC */ 67 68 /* 69 * We have up to 8 empty zeroed pages so we can map one of the right colour 70 * when needed. This is necessary only on R4000 / R4400 SC and MC versions 71 * where we have to avoid VCED / VECI exceptions for good performance at 72 * any price. Since page is never written to after the initialization we 73 * don't have to care about aliases on other CPUs. 74 */ 75 unsigned long empty_zero_page, zero_page_mask; 76 EXPORT_SYMBOL_GPL(empty_zero_page); 77 78 /* 79 * Not static inline because used by IP27 special magic initialization code 80 */ 81 void setup_zero_pages(void) 82 { 83 unsigned int order, i; 84 struct page *page; 85 86 if (cpu_has_vce) 87 order = 3; 88 else 89 order = 0; 90 91 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 92 if (!empty_zero_page) 93 panic("Oh boy, that early out of memory?"); 94 95 page = virt_to_page((void *)empty_zero_page); 96 split_page(page, order); 97 for (i = 0; i < (1 << order); i++, page++) 98 mark_page_reserved(page); 99 100 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; 101 } 102 103 #ifdef CONFIG_MIPS_MT_SMTC 104 static pte_t *kmap_coherent_pte; 105 static void __init kmap_coherent_init(void) 106 { 107 unsigned long vaddr; 108 109 /* cache the first coherent kmap pte */ 110 vaddr = __fix_to_virt(FIX_CMAP_BEGIN); 111 kmap_coherent_pte = kmap_get_fixmap_pte(vaddr); 112 } 113 #else 114 static inline void kmap_coherent_init(void) {} 115 #endif 116 117 void *kmap_coherent(struct page *page, unsigned long addr) 118 { 119 enum fixed_addresses idx; 120 unsigned long vaddr, flags, entrylo; 121 unsigned long old_ctx; 122 pte_t pte; 123 int tlbidx; 124 125 BUG_ON(Page_dcache_dirty(page)); 126 127 pagefault_disable(); 128 idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1); 129 #ifdef CONFIG_MIPS_MT_SMTC 130 idx += FIX_N_COLOURS * smp_processor_id() + 131 (in_interrupt() ? (FIX_N_COLOURS * NR_CPUS) : 0); 132 #else 133 idx += in_interrupt() ? FIX_N_COLOURS : 0; 134 #endif 135 vaddr = __fix_to_virt(FIX_CMAP_END - idx); 136 pte = mk_pte(page, PAGE_KERNEL); 137 #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32) 138 entrylo = pte.pte_high; 139 #else 140 entrylo = pte_to_entrylo(pte_val(pte)); 141 #endif 142 143 ENTER_CRITICAL(flags); 144 old_ctx = read_c0_entryhi(); 145 write_c0_entryhi(vaddr & (PAGE_MASK << 1)); 146 write_c0_entrylo0(entrylo); 147 write_c0_entrylo1(entrylo); 148 #ifdef CONFIG_MIPS_MT_SMTC 149 set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte); 150 /* preload TLB instead of local_flush_tlb_one() */ 151 mtc0_tlbw_hazard(); 152 tlb_probe(); 153 tlb_probe_hazard(); 154 tlbidx = read_c0_index(); 155 mtc0_tlbw_hazard(); 156 if (tlbidx < 0) 157 tlb_write_random(); 158 else 159 tlb_write_indexed(); 160 #else 161 tlbidx = read_c0_wired(); 162 write_c0_wired(tlbidx + 1); 163 write_c0_index(tlbidx); 164 mtc0_tlbw_hazard(); 165 tlb_write_indexed(); 166 #endif 167 tlbw_use_hazard(); 168 write_c0_entryhi(old_ctx); 169 EXIT_CRITICAL(flags); 170 171 return (void*) vaddr; 172 } 173 174 #define UNIQUE_ENTRYHI(idx) (CKSEG0 + ((idx) << (PAGE_SHIFT + 1))) 175 176 void kunmap_coherent(void) 177 { 178 #ifndef CONFIG_MIPS_MT_SMTC 179 unsigned int wired; 180 unsigned long flags, old_ctx; 181 182 ENTER_CRITICAL(flags); 183 old_ctx = read_c0_entryhi(); 184 wired = read_c0_wired() - 1; 185 write_c0_wired(wired); 186 write_c0_index(wired); 187 write_c0_entryhi(UNIQUE_ENTRYHI(wired)); 188 write_c0_entrylo0(0); 189 write_c0_entrylo1(0); 190 mtc0_tlbw_hazard(); 191 tlb_write_indexed(); 192 tlbw_use_hazard(); 193 write_c0_entryhi(old_ctx); 194 EXIT_CRITICAL(flags); 195 #endif 196 pagefault_enable(); 197 } 198 199 void copy_user_highpage(struct page *to, struct page *from, 200 unsigned long vaddr, struct vm_area_struct *vma) 201 { 202 void *vfrom, *vto; 203 204 vto = kmap_atomic(to); 205 if (cpu_has_dc_aliases && 206 page_mapped(from) && !Page_dcache_dirty(from)) { 207 vfrom = kmap_coherent(from, vaddr); 208 copy_page(vto, vfrom); 209 kunmap_coherent(); 210 } else { 211 vfrom = kmap_atomic(from); 212 copy_page(vto, vfrom); 213 kunmap_atomic(vfrom); 214 } 215 if ((!cpu_has_ic_fills_f_dc) || 216 pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK)) 217 flush_data_cache_page((unsigned long)vto); 218 kunmap_atomic(vto); 219 /* Make sure this page is cleared on other CPU's too before using it */ 220 smp_wmb(); 221 } 222 223 void copy_to_user_page(struct vm_area_struct *vma, 224 struct page *page, unsigned long vaddr, void *dst, const void *src, 225 unsigned long len) 226 { 227 if (cpu_has_dc_aliases && 228 page_mapped(page) && !Page_dcache_dirty(page)) { 229 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 230 memcpy(vto, src, len); 231 kunmap_coherent(); 232 } else { 233 memcpy(dst, src, len); 234 if (cpu_has_dc_aliases) 235 SetPageDcacheDirty(page); 236 } 237 if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc) 238 flush_cache_page(vma, vaddr, page_to_pfn(page)); 239 } 240 241 void copy_from_user_page(struct vm_area_struct *vma, 242 struct page *page, unsigned long vaddr, void *dst, const void *src, 243 unsigned long len) 244 { 245 if (cpu_has_dc_aliases && 246 page_mapped(page) && !Page_dcache_dirty(page)) { 247 void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); 248 memcpy(dst, vfrom, len); 249 kunmap_coherent(); 250 } else { 251 memcpy(dst, src, len); 252 if (cpu_has_dc_aliases) 253 SetPageDcacheDirty(page); 254 } 255 } 256 EXPORT_SYMBOL_GPL(copy_from_user_page); 257 258 void __init fixrange_init(unsigned long start, unsigned long end, 259 pgd_t *pgd_base) 260 { 261 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC) 262 pgd_t *pgd; 263 pud_t *pud; 264 pmd_t *pmd; 265 pte_t *pte; 266 int i, j, k; 267 unsigned long vaddr; 268 269 vaddr = start; 270 i = __pgd_offset(vaddr); 271 j = __pud_offset(vaddr); 272 k = __pmd_offset(vaddr); 273 pgd = pgd_base + i; 274 275 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) { 276 pud = (pud_t *)pgd; 277 for ( ; (j < PTRS_PER_PUD) && (vaddr < end); pud++, j++) { 278 pmd = (pmd_t *)pud; 279 for (; (k < PTRS_PER_PMD) && (vaddr < end); pmd++, k++) { 280 if (pmd_none(*pmd)) { 281 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); 282 set_pmd(pmd, __pmd((unsigned long)pte)); 283 BUG_ON(pte != pte_offset_kernel(pmd, 0)); 284 } 285 vaddr += PMD_SIZE; 286 } 287 k = 0; 288 } 289 j = 0; 290 } 291 #endif 292 } 293 294 #ifndef CONFIG_NEED_MULTIPLE_NODES 295 int page_is_ram(unsigned long pagenr) 296 { 297 int i; 298 299 for (i = 0; i < boot_mem_map.nr_map; i++) { 300 unsigned long addr, end; 301 302 switch (boot_mem_map.map[i].type) { 303 case BOOT_MEM_RAM: 304 case BOOT_MEM_INIT_RAM: 305 break; 306 default: 307 /* not usable memory */ 308 continue; 309 } 310 311 addr = PFN_UP(boot_mem_map.map[i].addr); 312 end = PFN_DOWN(boot_mem_map.map[i].addr + 313 boot_mem_map.map[i].size); 314 315 if (pagenr >= addr && pagenr < end) 316 return 1; 317 } 318 319 return 0; 320 } 321 322 void __init paging_init(void) 323 { 324 unsigned long max_zone_pfns[MAX_NR_ZONES]; 325 unsigned long lastpfn __maybe_unused; 326 327 pagetable_init(); 328 329 #ifdef CONFIG_HIGHMEM 330 kmap_init(); 331 #endif 332 kmap_coherent_init(); 333 334 #ifdef CONFIG_ZONE_DMA 335 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN; 336 #endif 337 #ifdef CONFIG_ZONE_DMA32 338 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN; 339 #endif 340 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 341 lastpfn = max_low_pfn; 342 #ifdef CONFIG_HIGHMEM 343 max_zone_pfns[ZONE_HIGHMEM] = highend_pfn; 344 lastpfn = highend_pfn; 345 346 if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) { 347 printk(KERN_WARNING "This processor doesn't support highmem." 348 " %ldk highmem ignored\n", 349 (highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10)); 350 max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn; 351 lastpfn = max_low_pfn; 352 } 353 #endif 354 355 free_area_init_nodes(max_zone_pfns); 356 } 357 358 #ifdef CONFIG_64BIT 359 static struct kcore_list kcore_kseg0; 360 #endif 361 362 static inline void mem_init_free_highmem(void) 363 { 364 #ifdef CONFIG_HIGHMEM 365 unsigned long tmp; 366 367 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) { 368 struct page *page = pfn_to_page(tmp); 369 370 if (!page_is_ram(tmp)) 371 SetPageReserved(page); 372 else 373 free_highmem_page(page); 374 } 375 #endif 376 } 377 378 void __init mem_init(void) 379 { 380 #ifdef CONFIG_HIGHMEM 381 #ifdef CONFIG_DISCONTIGMEM 382 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet" 383 #endif 384 max_mapnr = highend_pfn ? highend_pfn : max_low_pfn; 385 #else 386 max_mapnr = max_low_pfn; 387 #endif 388 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); 389 390 free_all_bootmem(); 391 setup_zero_pages(); /* Setup zeroed pages. */ 392 mem_init_free_highmem(); 393 mem_init_print_info(NULL); 394 395 #ifdef CONFIG_64BIT 396 if ((unsigned long) &_text > (unsigned long) CKSEG0) 397 /* The -4 is a hack so that user tools don't have to handle 398 the overflow. */ 399 kclist_add(&kcore_kseg0, (void *) CKSEG0, 400 0x80000000 - 4, KCORE_TEXT); 401 #endif 402 } 403 #endif /* !CONFIG_NEED_MULTIPLE_NODES */ 404 405 void free_init_pages(const char *what, unsigned long begin, unsigned long end) 406 { 407 unsigned long pfn; 408 409 for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) { 410 struct page *page = pfn_to_page(pfn); 411 void *addr = phys_to_virt(PFN_PHYS(pfn)); 412 413 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE); 414 free_reserved_page(page); 415 } 416 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); 417 } 418 419 #ifdef CONFIG_BLK_DEV_INITRD 420 void free_initrd_mem(unsigned long start, unsigned long end) 421 { 422 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM, 423 "initrd"); 424 } 425 #endif 426 427 void __init_refok free_initmem(void) 428 { 429 prom_free_prom_memory(); 430 free_initmem_default(POISON_FREE_INITMEM); 431 } 432 433 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT 434 unsigned long pgd_current[NR_CPUS]; 435 #endif 436 437 /* 438 * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER 439 * are constants. So we use the variants from asm-offset.h until that gcc 440 * will officially be retired. 441 * 442 * Align swapper_pg_dir in to 64K, allows its address to be loaded 443 * with a single LUI instruction in the TLB handlers. If we used 444 * __aligned(64K), its size would get rounded up to the alignment 445 * size, and waste space. So we place it in its own section and align 446 * it in the linker script. 447 */ 448 pgd_t swapper_pg_dir[_PTRS_PER_PGD] __section(.bss..swapper_pg_dir); 449 #ifndef __PAGETABLE_PMD_FOLDED 450 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned_bss; 451 #endif 452 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss; 453