arch/mips/mm/init.c

   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/kernel.h>
  17 #include <linux/errno.h>
  18 #include <linux/string.h>
  19 #include <linux/types.h>
  20 #include <linux/pagemap.h>
  21 #include <linux/ptrace.h>
  22 #include <linux/mman.h>
  23 #include <linux/mm.h>
  24 #include <linux/bootmem.h>
  25 #include <linux/highmem.h>
  26 #include <linux/swap.h>
  27 #include <linux/proc_fs.h>
  28 #include <linux/pfn.h>
  29
  30 #include <asm/asm-offsets.h>
  31 #include <asm/bootinfo.h>
  32 #include <asm/cachectl.h>
  33 #include <asm/cpu.h>
  34 #include <asm/dma.h>
  35 #include <asm/kmap_types.h>
  36 #include <asm/mmu_context.h>
  37 #include <asm/sections.h>
  38 #include <asm/pgtable.h>
  39 #include <asm/pgalloc.h>
  40 #include <asm/tlb.h>
  41 #include <asm/fixmap.h>
  42
  43 /* Atomicity and interruptability */
  44 #ifdef CONFIG_MIPS_MT_SMTC
  45
  46 #include <asm/mipsmtregs.h>
  47
  48 #define ENTER_CRITICAL(flags) \
  49         { \
  50         unsigned int mvpflags; \
  51         local_irq_save(flags);\
  52         mvpflags = dvpe()
  53 #define EXIT_CRITICAL(flags) \
  54         evpe(mvpflags); \
  55         local_irq_restore(flags); \
  56         }
  57 #else
  58
  59 #define ENTER_CRITICAL(flags) local_irq_save(flags)
  60 #define EXIT_CRITICAL(flags) local_irq_restore(flags)
  61
  62 #endif /* CONFIG_MIPS_MT_SMTC */
  63
  64 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  65
  66 /*
  67  * We have up to 8 empty zeroed pages so we can map one of the right colour
  68  * when needed.  This is necessary only on R4000 / R4400 SC and MC versions
  69  * where we have to avoid VCED / VECI exceptions for good performance at
  70  * any price.  Since page is never written to after the initialization we
  71  * don't have to care about aliases on other CPUs.
  72  */
  73 unsigned long empty_zero_page, zero_page_mask;
  74
  75 /*
  76  * Not static inline because used by IP27 special magic initialization code
  77  */
  78 unsigned long setup_zero_pages(void)
  79 {
  80         unsigned int order;
  81         unsigned long size;
  82         struct page *page;
  83
  84         if (cpu_has_vce)
  85                 order = 3;
  86         else
  87                 order = 0;
  88
  89         empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
  90         if (!empty_zero_page)
  91                 panic("Oh boy, that early out of memory?");
  92
  93         page = virt_to_page((void *)empty_zero_page);
  94         split_page(page, order);
  95         while (page < virt_to_page((void *)(empty_zero_page + (PAGE_SIZE << order)))) {
  96                 SetPageReserved(page);
  97                 page++;
  98         }
  99
 100         size = PAGE_SIZE << order;
 101         zero_page_mask = (size - 1) & PAGE_MASK;
 102
 103         return 1UL << order;
 104 }
 105
 106 /*
 107  * These are almost like kmap_atomic / kunmap_atmic except they take an
 108  * additional address argument as the hint.
 109  */
 110
 111 #define kmap_get_fixmap_pte(vaddr)                                      \
 112         pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr))
 113
 114 #ifdef CONFIG_MIPS_MT_SMTC
 115 static pte_t *kmap_coherent_pte;
 116 static void __init kmap_coherent_init(void)
 117 {
 118         unsigned long vaddr;
 119
 120         /* cache the first coherent kmap pte */
 121         vaddr = __fix_to_virt(FIX_CMAP_BEGIN);
 122         kmap_coherent_pte = kmap_get_fixmap_pte(vaddr);
 123 }
 124 #else
 125 static inline void kmap_coherent_init(void) {}
 126 #endif
 127
 128 void *kmap_coherent(struct page *page, unsigned long addr)
 129 {
 130         enum fixed_addresses idx;
 131         unsigned long vaddr, flags, entrylo;
 132         unsigned long old_ctx;
 133         pte_t pte;
 134         int tlbidx;
 135
 136         BUG_ON(Page_dcache_dirty(page));
 137
 138         inc_preempt_count();
 139         idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1);
 140 #ifdef CONFIG_MIPS_MT_SMTC
 141         idx += FIX_N_COLOURS * smp_processor_id();
 142 #endif
 143         vaddr = __fix_to_virt(FIX_CMAP_END - idx);
 144         pte = mk_pte(page, PAGE_KERNEL);
 145 #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32_R1)
 146         entrylo = pte.pte_high;
 147 #else
 148         entrylo = pte_val(pte) >> 6;
 149 #endif
 150
 151         ENTER_CRITICAL(flags);
 152         old_ctx = read_c0_entryhi();
 153         write_c0_entryhi(vaddr & (PAGE_MASK << 1));
 154         write_c0_entrylo0(entrylo);
 155         write_c0_entrylo1(entrylo);
 156 #ifdef CONFIG_MIPS_MT_SMTC
 157         set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte);
 158         /* preload TLB instead of local_flush_tlb_one() */
 159         mtc0_tlbw_hazard();
 160         tlb_probe();
 161         tlb_probe_hazard();
 162         tlbidx = read_c0_index();
 163         mtc0_tlbw_hazard();
 164         if (tlbidx < 0)
 165                 tlb_write_random();
 166         else
 167                 tlb_write_indexed();
 168 #else
 169         tlbidx = read_c0_wired();
 170         write_c0_wired(tlbidx + 1);
 171         write_c0_index(tlbidx);
 172         mtc0_tlbw_hazard();
 173         tlb_write_indexed();
 174 #endif
 175         tlbw_use_hazard();
 176         write_c0_entryhi(old_ctx);
 177         EXIT_CRITICAL(flags);
 178
 179         return (void*) vaddr;
 180 }
 181
 182 #define UNIQUE_ENTRYHI(idx) (CKSEG0 + ((idx) << (PAGE_SHIFT + 1)))
 183
 184 void kunmap_coherent(void)
 185 {
 186 #ifndef CONFIG_MIPS_MT_SMTC
 187         unsigned int wired;
 188         unsigned long flags, old_ctx;
 189
 190         ENTER_CRITICAL(flags);
 191         old_ctx = read_c0_entryhi();
 192         wired = read_c0_wired() - 1;
 193         write_c0_wired(wired);
 194         write_c0_index(wired);
 195         write_c0_entryhi(UNIQUE_ENTRYHI(wired));
 196         write_c0_entrylo0(0);
 197         write_c0_entrylo1(0);
 198         mtc0_tlbw_hazard();
 199         tlb_write_indexed();
 200         tlbw_use_hazard();
 201         write_c0_entryhi(old_ctx);
 202         EXIT_CRITICAL(flags);
 203 #endif
 204         dec_preempt_count();
 205         preempt_check_resched();
 206 }
 207
 208 void copy_user_highpage(struct page *to, struct page *from,
 209         unsigned long vaddr, struct vm_area_struct *vma)
 210 {
 211         void *vfrom, *vto;
 212
 213         vto = kmap_atomic(to, KM_USER1);
 214 <<<<<<< HEAD:arch/mips/mm/init.c
 215         if (cpu_has_dc_aliases && page_mapped(from)) {
 216 =======
 217         if (cpu_has_dc_aliases &&
 218             page_mapped(from) && !Page_dcache_dirty(from)) {
 219 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:arch/mips/mm/init.c
 220                 vfrom = kmap_coherent(from, vaddr);
 221                 copy_page(vto, vfrom);
 222                 kunmap_coherent();
 223         } else {
 224                 vfrom = kmap_atomic(from, KM_USER0);
 225                 copy_page(vto, vfrom);
 226                 kunmap_atomic(vfrom, KM_USER0);
 227         }
 228         if (((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc) ||
 229             pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
 230                 flush_data_cache_page((unsigned long)vto);
 231         kunmap_atomic(vto, KM_USER1);
 232         /* Make sure this page is cleared on other CPU's too before using it */
 233         smp_wmb();
 234 }
 235
 236 EXPORT_SYMBOL(copy_user_highpage);
 237
 238 void copy_to_user_page(struct vm_area_struct *vma,
 239         struct page *page, unsigned long vaddr, void *dst, const void *src,
 240         unsigned long len)
 241 {
 242 <<<<<<< HEAD:arch/mips/mm/init.c
 243         if (cpu_has_dc_aliases && page_mapped(page)) {
 244 =======
 245         if (cpu_has_dc_aliases &&
 246             page_mapped(page) && !Page_dcache_dirty(page)) {
 247 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:arch/mips/mm/init.c
 248                 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
 249                 memcpy(vto, src, len);
 250                 kunmap_coherent();
 251         } else {
 252                 memcpy(dst, src, len);
 253                 if (cpu_has_dc_aliases)
 254                         SetPageDcacheDirty(page);
 255         }
 256         if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc)
 257                 flush_cache_page(vma, vaddr, page_to_pfn(page));
 258 }
 259
 260 EXPORT_SYMBOL(copy_to_user_page);
 261
 262 void copy_from_user_page(struct vm_area_struct *vma,
 263         struct page *page, unsigned long vaddr, void *dst, const void *src,
 264         unsigned long len)
 265 {
 266 <<<<<<< HEAD:arch/mips/mm/init.c
 267         if (cpu_has_dc_aliases && page_mapped(page)) {
 268 =======
 269         if (cpu_has_dc_aliases &&
 270             page_mapped(page) && !Page_dcache_dirty(page)) {
 271 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:arch/mips/mm/init.c
 272                 void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
 273                 memcpy(dst, vfrom, len);
 274                 kunmap_coherent();
 275         } else {
 276                 memcpy(dst, src, len);
 277                 if (cpu_has_dc_aliases)
 278                         SetPageDcacheDirty(page);
 279         }
 280 }
 281
 282 EXPORT_SYMBOL(copy_from_user_page);
 283
 284
 285 #ifdef CONFIG_HIGHMEM
 286 unsigned long highstart_pfn, highend_pfn;
 287
 288 pte_t *kmap_pte;
 289 pgprot_t kmap_prot;
 290
 291 static void __init kmap_init(void)
 292 {
 293         unsigned long kmap_vstart;
 294
 295         /* cache the first kmap pte */
 296         kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
 297         kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
 298
 299         kmap_prot = PAGE_KERNEL;
 300 }
 301 #endif /* CONFIG_HIGHMEM */
 302
 303 void __init fixrange_init(unsigned long start, unsigned long end,
 304         pgd_t *pgd_base)
 305 {
 306 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC)
 307         pgd_t *pgd;
 308         pud_t *pud;
 309         pmd_t *pmd;
 310         pte_t *pte;
 311         int i, j, k;
 312         unsigned long vaddr;
 313
 314         vaddr = start;
 315         i = __pgd_offset(vaddr);
 316         j = __pud_offset(vaddr);
 317         k = __pmd_offset(vaddr);
 318         pgd = pgd_base + i;
 319
 320         for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
 321                 pud = (pud_t *)pgd;
 322                 for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
 323                         pmd = (pmd_t *)pud;
 324                         for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
 325                                 if (pmd_none(*pmd)) {
 326                                         pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
 327                                         set_pmd(pmd, __pmd((unsigned long)pte));
 328                                         if (pte != pte_offset_kernel(pmd, 0))
 329                                                 BUG();
 330                                 }
 331                                 vaddr += PMD_SIZE;
 332                         }
 333                         k = 0;
 334                 }
 335                 j = 0;
 336         }
 337 #endif
 338 }
 339
 340 #ifndef CONFIG_NEED_MULTIPLE_NODES
 341 static int __init page_is_ram(unsigned long pagenr)
 342 {
 343         int i;
 344
 345         for (i = 0; i < boot_mem_map.nr_map; i++) {
 346                 unsigned long addr, end;
 347
 348                 if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
 349                         /* not usable memory */
 350                         continue;
 351
 352                 addr = PFN_UP(boot_mem_map.map[i].addr);
 353                 end = PFN_DOWN(boot_mem_map.map[i].addr +
 354                                boot_mem_map.map[i].size);
 355
 356                 if (pagenr >= addr && pagenr < end)
 357                         return 1;
 358         }
 359
 360         return 0;
 361 }
 362
 363 void __init paging_init(void)
 364 {
 365         unsigned long max_zone_pfns[MAX_NR_ZONES];
 366         unsigned long lastpfn;
 367
 368         pagetable_init();
 369
 370 #ifdef CONFIG_HIGHMEM
 371         kmap_init();
 372 #endif
 373         kmap_coherent_init();
 374
 375 #ifdef CONFIG_ZONE_DMA
 376         max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
 377 #endif
 378 #ifdef CONFIG_ZONE_DMA32
 379         max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
 380 #endif
 381         max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
 382         lastpfn = max_low_pfn;
 383 #ifdef CONFIG_HIGHMEM
 384         max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
 385         lastpfn = highend_pfn;
 386
 387         if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) {
 388                 printk(KERN_WARNING "This processor doesn't support highmem."
 389                        " %ldk highmem ignored\n",
 390                        (highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10));
 391                 max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn;
 392                 lastpfn = max_low_pfn;
 393         }
 394 #endif
 395
 396         free_area_init_nodes(max_zone_pfns);
 397 }
 398
 399 static struct kcore_list kcore_mem, kcore_vmalloc;
 400 #ifdef CONFIG_64BIT
 401 static struct kcore_list kcore_kseg0;
 402 #endif
 403
 404 void __init mem_init(void)
 405 {
 406         unsigned long codesize, reservedpages, datasize, initsize;
 407         unsigned long tmp, ram;
 408
 409 #ifdef CONFIG_HIGHMEM
 410 #ifdef CONFIG_DISCONTIGMEM
 411 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
 412 #endif
 413         max_mapnr = highend_pfn;
 414 #else
 415         max_mapnr = max_low_pfn;
 416 #endif
 417         high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
 418
 419         totalram_pages += free_all_bootmem();
 420         totalram_pages -= setup_zero_pages();   /* Setup zeroed pages.  */
 421
 422         reservedpages = ram = 0;
 423         for (tmp = 0; tmp < max_low_pfn; tmp++)
 424                 if (page_is_ram(tmp)) {
 425                         ram++;
 426                         if (PageReserved(pfn_to_page(tmp)))
 427                                 reservedpages++;
 428                 }
 429         num_physpages = ram;
 430
 431 #ifdef CONFIG_HIGHMEM
 432         for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
 433                 struct page *page = pfn_to_page(tmp);
 434
 435                 if (!page_is_ram(tmp)) {
 436                         SetPageReserved(page);
 437                         continue;
 438                 }
 439                 ClearPageReserved(page);
 440                 init_page_count(page);
 441                 __free_page(page);
 442                 totalhigh_pages++;
 443         }
 444         totalram_pages += totalhigh_pages;
 445         num_physpages += totalhigh_pages;
 446 #endif
 447
 448         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
 449         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
 450         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
 451
 452 #ifdef CONFIG_64BIT
 453         if ((unsigned long) &_text > (unsigned long) CKSEG0)
 454                 /* The -4 is a hack so that user tools don't have to handle
 455                    the overflow.  */
 456                 kclist_add(&kcore_kseg0, (void *) CKSEG0, 0x80000000 - 4);
 457 #endif
 458         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
 459         kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
 460                    VMALLOC_END-VMALLOC_START);
 461
 462         printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
 463                "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
 464                (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 465                ram << (PAGE_SHIFT-10),
 466                codesize >> 10,
 467                reservedpages << (PAGE_SHIFT-10),
 468                datasize >> 10,
 469                initsize >> 10,
 470                (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
 471 }
 472 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
 473
 474 void free_init_pages(const char *what, unsigned long begin, unsigned long end)
 475 {
 476         unsigned long pfn;
 477
 478         for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
 479                 struct page *page = pfn_to_page(pfn);
 480                 void *addr = phys_to_virt(PFN_PHYS(pfn));
 481
 482                 ClearPageReserved(page);
 483                 init_page_count(page);
 484                 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
 485                 __free_page(page);
 486                 totalram_pages++;
 487         }
 488         printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
 489 }
 490
 491 #ifdef CONFIG_BLK_DEV_INITRD
 492 void free_initrd_mem(unsigned long start, unsigned long end)
 493 {
 494         free_init_pages("initrd memory",
 495                         virt_to_phys((void *)start),
 496                         virt_to_phys((void *)end));
 497 }
 498 #endif
 499
 500 void __init_refok free_initmem(void)
 501 {
 502         prom_free_prom_memory();
 503         free_init_pages("unused kernel memory",
 504                         __pa_symbol(&__init_begin),
 505                         __pa_symbol(&__init_end));
 506 }
 507
 508 unsigned long pgd_current[NR_CPUS];
 509 /*
 510  * On 64-bit we've got three-level pagetables with a slightly
 511  * different layout ...
 512  */
 513 #define __page_aligned(order) __attribute__((__aligned__(PAGE_SIZE<<order)))
 514
 515 /*
 516  * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER
 517  * are constants.  So we use the variants from asm-offset.h until that gcc
 518  * will officially be retired.
 519  */
 520 pgd_t swapper_pg_dir[_PTRS_PER_PGD] __page_aligned(_PGD_ORDER);
 521 #ifdef CONFIG_64BIT
 522 #ifdef MODULE_START
 523 pgd_t module_pg_dir[PTRS_PER_PGD] __page_aligned(PGD_ORDER);
 524 #endif
 525 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned(PMD_ORDER);
 526 #endif
 527 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER);