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/init.h>
  12 #include <linux/module.h>
  13 #include <linux/signal.h>
  14 #include <linux/sched.h>
  15 #include <linux/kernel.h>
  16 #include <linux/errno.h>
  17 #include <linux/string.h>
  18 #include <linux/types.h>
  19 #include <linux/pagemap.h>
  20 #include <linux/ptrace.h>
  21 #include <linux/mman.h>
  22 #include <linux/mm.h>
  23 #include <linux/bootmem.h>
  24 #include <linux/highmem.h>
  25 #include <linux/swap.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/pfn.h>
  28
  29 #include <asm/bootinfo.h>
  30 #include <asm/cachectl.h>
  31 #include <asm/cpu.h>
  32 #include <asm/dma.h>
  33 #include <asm/kmap_types.h>
  34 #include <asm/mmu_context.h>
  35 #include <asm/sections.h>
  36 #include <asm/pgtable.h>
  37 #include <asm/pgalloc.h>
  38 #include <asm/tlb.h>
  39 #include <asm/fixmap.h>
  40
  41 /* Atomicity and interruptability */
  42 #ifdef CONFIG_MIPS_MT_SMTC
  43
  44 #include <asm/mipsmtregs.h>
  45
  46 #define ENTER_CRITICAL(flags) \
  47         { \
  48         unsigned int mvpflags; \
  49         local_irq_save(flags);\
  50         mvpflags = dvpe()
  51 #define EXIT_CRITICAL(flags) \
  52         evpe(mvpflags); \
  53         local_irq_restore(flags); \
  54         }
  55 #else
  56
  57 #define ENTER_CRITICAL(flags) local_irq_save(flags)
  58 #define EXIT_CRITICAL(flags) local_irq_restore(flags)
  59
  60 #endif /* CONFIG_MIPS_MT_SMTC */
  61
  62 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  63
  64 unsigned long highstart_pfn, highend_pfn;
  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(empty_zero_page);
  94         split_page(page, order);
  95         while (page < virt_to_page(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 static inline 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         inc_preempt_count();
 137         idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1);
 138 #ifdef CONFIG_MIPS_MT_SMTC
 139         idx += FIX_N_COLOURS * smp_processor_id();
 140 #endif
 141         vaddr = __fix_to_virt(FIX_CMAP_END - idx);
 142         pte = mk_pte(page, PAGE_KERNEL);
 143 #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32_R1)
 144         entrylo = pte.pte_high;
 145 #else
 146         entrylo = pte_val(pte) >> 6;
 147 #endif
 148
 149         ENTER_CRITICAL(flags);
 150         old_ctx = read_c0_entryhi();
 151         write_c0_entryhi(vaddr & (PAGE_MASK << 1));
 152         write_c0_entrylo0(entrylo);
 153         write_c0_entrylo1(entrylo);
 154 #ifdef CONFIG_MIPS_MT_SMTC
 155         set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte);
 156         /* preload TLB instead of local_flush_tlb_one() */
 157         mtc0_tlbw_hazard();
 158         tlb_probe();
 159         tlb_probe_hazard();
 160         tlbidx = read_c0_index();
 161         mtc0_tlbw_hazard();
 162         if (tlbidx < 0)
 163                 tlb_write_random();
 164         else
 165                 tlb_write_indexed();
 166 #else
 167         tlbidx = read_c0_wired();
 168         write_c0_wired(tlbidx + 1);
 169         write_c0_index(tlbidx);
 170         mtc0_tlbw_hazard();
 171         tlb_write_indexed();
 172 #endif
 173         tlbw_use_hazard();
 174         write_c0_entryhi(old_ctx);
 175         EXIT_CRITICAL(flags);
 176
 177         return (void*) vaddr;
 178 }
 179
 180 #define UNIQUE_ENTRYHI(idx) (CKSEG0 + ((idx) << (PAGE_SHIFT + 1)))
 181
 182 static inline void kunmap_coherent(struct page *page)
 183 {
 184 #ifndef CONFIG_MIPS_MT_SMTC
 185         unsigned int wired;
 186         unsigned long flags, old_ctx;
 187
 188         ENTER_CRITICAL(flags);
 189         old_ctx = read_c0_entryhi();
 190         wired = read_c0_wired() - 1;
 191         write_c0_wired(wired);
 192         write_c0_index(wired);
 193         write_c0_entryhi(UNIQUE_ENTRYHI(wired));
 194         write_c0_entrylo0(0);
 195         write_c0_entrylo1(0);
 196         mtc0_tlbw_hazard();
 197         tlb_write_indexed();
 198         tlbw_use_hazard();
 199         write_c0_entryhi(old_ctx);
 200         EXIT_CRITICAL(flags);
 201 #endif
 202         dec_preempt_count();
 203         preempt_check_resched();
 204 }
 205
 206 void copy_to_user_page(struct vm_area_struct *vma,
 207         struct page *page, unsigned long vaddr, void *dst, const void *src,
 208         unsigned long len)
 209 {
 210         if (cpu_has_dc_aliases) {
 211                 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
 212                 memcpy(vto, src, len);
 213                 kunmap_coherent(page);
 214         } else
 215                 memcpy(dst, src, len);
 216         if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc)
 217                 flush_cache_page(vma, vaddr, page_to_pfn(page));
 218 }
 219
 220 EXPORT_SYMBOL(copy_to_user_page);
 221
 222 void copy_from_user_page(struct vm_area_struct *vma,
 223         struct page *page, unsigned long vaddr, void *dst, const void *src,
 224         unsigned long len)
 225 {
 226         if (cpu_has_dc_aliases) {
 227                 void *vfrom =
 228                         kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
 229                 memcpy(dst, vfrom, len);
 230                 kunmap_coherent(page);
 231         } else
 232                 memcpy(dst, src, len);
 233 }
 234
 235 EXPORT_SYMBOL(copy_from_user_page);
 236
 237
 238 #ifdef CONFIG_HIGHMEM
 239 pte_t *kmap_pte;
 240 pgprot_t kmap_prot;
 241
 242 static void __init kmap_init(void)
 243 {
 244         unsigned long kmap_vstart;
 245
 246         /* cache the first kmap pte */
 247         kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
 248         kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
 249
 250         kmap_prot = PAGE_KERNEL;
 251 }
 252 #endif /* CONFIG_HIGHMEM */
 253
 254 void __init fixrange_init(unsigned long start, unsigned long end,
 255         pgd_t *pgd_base)
 256 {
 257 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC)
 258         pgd_t *pgd;
 259         pud_t *pud;
 260         pmd_t *pmd;
 261         pte_t *pte;
 262         int i, j, k;
 263         unsigned long vaddr;
 264
 265         vaddr = start;
 266         i = __pgd_offset(vaddr);
 267         j = __pud_offset(vaddr);
 268         k = __pmd_offset(vaddr);
 269         pgd = pgd_base + i;
 270
 271         for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
 272                 pud = (pud_t *)pgd;
 273                 for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
 274                         pmd = (pmd_t *)pud;
 275                         for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
 276                                 if (pmd_none(*pmd)) {
 277                                         pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
 278                                         set_pmd(pmd, __pmd((unsigned long)pte));
 279                                         if (pte != pte_offset_kernel(pmd, 0))
 280                                                 BUG();
 281                                 }
 282                                 vaddr += PMD_SIZE;
 283                         }
 284                         k = 0;
 285                 }
 286                 j = 0;
 287         }
 288 #endif
 289 }
 290
 291 #ifndef CONFIG_NEED_MULTIPLE_NODES
 292 extern void pagetable_init(void);
 293
 294 static int __init page_is_ram(unsigned long pagenr)
 295 {
 296         int i;
 297
 298         for (i = 0; i < boot_mem_map.nr_map; i++) {
 299                 unsigned long addr, end;
 300
 301                 if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
 302                         /* not usable memory */
 303                         continue;
 304
 305                 addr = PFN_UP(boot_mem_map.map[i].addr);
 306                 end = PFN_DOWN(boot_mem_map.map[i].addr +
 307                                boot_mem_map.map[i].size);
 308
 309                 if (pagenr >= addr && pagenr < end)
 310                         return 1;
 311         }
 312
 313         return 0;
 314 }
 315
 316 void __init paging_init(void)
 317 {
 318         unsigned long zones_size[MAX_NR_ZONES] = { 0, };
 319         unsigned long max_dma, high, low;
 320 #ifndef CONFIG_FLATMEM
 321         unsigned long zholes_size[MAX_NR_ZONES] = { 0, };
 322         unsigned long i, j, pfn;
 323 #endif
 324
 325         pagetable_init();
 326
 327 #ifdef CONFIG_HIGHMEM
 328         kmap_init();
 329 #endif
 330         kmap_coherent_init();
 331
 332         max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
 333         low = max_low_pfn;
 334         high = highend_pfn;
 335
 336 #ifdef CONFIG_ISA
 337         if (low < max_dma)
 338                 zones_size[ZONE_DMA] = low;
 339         else {
 340                 zones_size[ZONE_DMA] = max_dma;
 341                 zones_size[ZONE_NORMAL] = low - max_dma;
 342         }
 343 #else
 344         zones_size[ZONE_DMA] = low;
 345 #endif
 346 #ifdef CONFIG_HIGHMEM
 347         if (cpu_has_dc_aliases) {
 348                 printk(KERN_WARNING "This processor doesn't support highmem.");
 349                 if (high - low)
 350                         printk(" %ldk highmem ignored", high - low);
 351                 printk("\n");
 352         } else
 353                 zones_size[ZONE_HIGHMEM] = high - low;
 354 #endif
 355
 356 #ifdef CONFIG_FLATMEM
 357         free_area_init(zones_size);
 358 #else
 359         pfn = 0;
 360         for (i = 0; i < MAX_NR_ZONES; i++)
 361                 for (j = 0; j < zones_size[i]; j++, pfn++)
 362                         if (!page_is_ram(pfn))
 363                                 zholes_size[i]++;
 364         free_area_init_node(0, NODE_DATA(0), zones_size, 0, zholes_size);
 365 #endif
 366 }
 367
 368 static struct kcore_list kcore_mem, kcore_vmalloc;
 369 #ifdef CONFIG_64BIT
 370 static struct kcore_list kcore_kseg0;
 371 #endif
 372
 373 void __init mem_init(void)
 374 {
 375         unsigned long codesize, reservedpages, datasize, initsize;
 376         unsigned long tmp, ram;
 377
 378 #ifdef CONFIG_HIGHMEM
 379 #ifdef CONFIG_DISCONTIGMEM
 380 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
 381 #endif
 382         max_mapnr = highend_pfn;
 383 #else
 384         max_mapnr = max_low_pfn;
 385 #endif
 386         high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
 387
 388         totalram_pages += free_all_bootmem();
 389         totalram_pages -= setup_zero_pages();   /* Setup zeroed pages.  */
 390
 391         reservedpages = ram = 0;
 392         for (tmp = 0; tmp < max_low_pfn; tmp++)
 393                 if (page_is_ram(tmp)) {
 394                         ram++;
 395                         if (PageReserved(pfn_to_page(tmp)))
 396                                 reservedpages++;
 397                 }
 398         num_physpages = ram;
 399
 400 #ifdef CONFIG_HIGHMEM
 401         for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
 402                 struct page *page = mem_map + tmp;
 403
 404                 if (!page_is_ram(tmp)) {
 405                         SetPageReserved(page);
 406                         continue;
 407                 }
 408                 ClearPageReserved(page);
 409 #ifdef CONFIG_LIMITED_DMA
 410                 set_page_address(page, lowmem_page_address(page));
 411 #endif
 412                 init_page_count(page);
 413                 __free_page(page);
 414                 totalhigh_pages++;
 415         }
 416         totalram_pages += totalhigh_pages;
 417         num_physpages += totalhigh_pages;
 418 #endif
 419
 420         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
 421         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
 422         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
 423
 424 #ifdef CONFIG_64BIT
 425         if ((unsigned long) &_text > (unsigned long) CKSEG0)
 426                 /* The -4 is a hack so that user tools don't have to handle
 427                    the overflow.  */
 428                 kclist_add(&kcore_kseg0, (void *) CKSEG0, 0x80000000 - 4);
 429 #endif
 430         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
 431         kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
 432                    VMALLOC_END-VMALLOC_START);
 433
 434         printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
 435                "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
 436                (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 437                ram << (PAGE_SHIFT-10),
 438                codesize >> 10,
 439                reservedpages << (PAGE_SHIFT-10),
 440                datasize >> 10,
 441                initsize >> 10,
 442                (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
 443 }
 444 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
 445
 446 void free_init_pages(char *what, unsigned long begin, unsigned long end)
 447 {
 448         unsigned long addr;
 449
 450         for (addr = begin; addr < end; addr += PAGE_SIZE) {
 451                 ClearPageReserved(virt_to_page(addr));
 452                 init_page_count(virt_to_page(addr));
 453                 memset((void *)addr, 0xcc, PAGE_SIZE);
 454                 free_page(addr);
 455                 totalram_pages++;
 456         }
 457         printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
 458 }
 459
 460 #ifdef CONFIG_BLK_DEV_INITRD
 461 void free_initrd_mem(unsigned long start, unsigned long end)
 462 {
 463 #ifdef CONFIG_64BIT
 464         /* Switch from KSEG0 to XKPHYS addresses */
 465         start = (unsigned long)phys_to_virt(CPHYSADDR(start));
 466         end = (unsigned long)phys_to_virt(CPHYSADDR(end));
 467 #endif
 468         free_init_pages("initrd memory", start, end);
 469 }
 470 #endif
 471
 472 extern unsigned long prom_free_prom_memory(void);
 473
 474 void free_initmem(void)
 475 {
 476         unsigned long start, end, freed;
 477
 478         freed = prom_free_prom_memory();
 479         if (freed)
 480                 printk(KERN_INFO "Freeing firmware memory: %ldk freed\n",freed);
 481
 482         start = (unsigned long)(&__init_begin);
 483         end = (unsigned long)(&__init_end);
 484 #ifdef CONFIG_64BIT
 485         start = PAGE_OFFSET | CPHYSADDR(start);
 486         end = PAGE_OFFSET | CPHYSADDR(end);
 487 #endif
 488         free_init_pages("unused kernel memory", start, end);
 489 }