linux/arch/sparc/mm/init_32.c
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   1/*
   2 *  linux/arch/sparc/mm/init.c
   3 *
   4 *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
   5 *  Copyright (C) 1995 Eddie C. Dost (ecd@skynet.be)
   6 *  Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   7 *  Copyright (C) 2000 Anton Blanchard (anton@samba.org)
   8 */
   9
  10#include <linux/module.h>
  11#include <linux/signal.h>
  12#include <linux/sched.h>
  13#include <linux/kernel.h>
  14#include <linux/errno.h>
  15#include <linux/string.h>
  16#include <linux/types.h>
  17#include <linux/ptrace.h>
  18#include <linux/mman.h>
  19#include <linux/mm.h>
  20#include <linux/swap.h>
  21#include <linux/initrd.h>
  22#include <linux/init.h>
  23#include <linux/highmem.h>
  24#include <linux/bootmem.h>
  25#include <linux/pagemap.h>
  26#include <linux/poison.h>
  27
  28#include <asm/sections.h>
  29#include <asm/system.h>
  30#include <asm/vac-ops.h>
  31#include <asm/page.h>
  32#include <asm/pgtable.h>
  33#include <asm/vaddrs.h>
  34#include <asm/pgalloc.h>        /* bug in asm-generic/tlb.h: check_pgt_cache */
  35#include <asm/tlb.h>
  36#include <asm/prom.h>
  37#include <asm/leon.h>
  38
  39DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  40
  41unsigned long *sparc_valid_addr_bitmap;
  42EXPORT_SYMBOL(sparc_valid_addr_bitmap);
  43
  44unsigned long phys_base;
  45EXPORT_SYMBOL(phys_base);
  46
  47unsigned long pfn_base;
  48EXPORT_SYMBOL(pfn_base);
  49
  50unsigned long page_kernel;
  51EXPORT_SYMBOL(page_kernel);
  52
  53struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
  54unsigned long sparc_unmapped_base;
  55
  56struct pgtable_cache_struct pgt_quicklists;
  57
  58/* Initial ramdisk setup */
  59extern unsigned int sparc_ramdisk_image;
  60extern unsigned int sparc_ramdisk_size;
  61
  62unsigned long highstart_pfn, highend_pfn;
  63
  64pte_t *kmap_pte;
  65pgprot_t kmap_prot;
  66
  67#define kmap_get_fixmap_pte(vaddr) \
  68        pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr))
  69
  70void __init kmap_init(void)
  71{
  72        /* cache the first kmap pte */
  73        kmap_pte = kmap_get_fixmap_pte(__fix_to_virt(FIX_KMAP_BEGIN));
  74        kmap_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE);
  75}
  76
  77void show_mem(void)
  78{
  79        printk("Mem-info:\n");
  80        show_free_areas();
  81        printk("Free swap:       %6ldkB\n",
  82               nr_swap_pages << (PAGE_SHIFT-10));
  83        printk("%ld pages of RAM\n", totalram_pages);
  84        printk("%ld free pages\n", nr_free_pages());
  85#if 0 /* undefined pgtable_cache_size, pgd_cache_size */
  86        printk("%ld pages in page table cache\n",pgtable_cache_size);
  87#ifndef CONFIG_SMP
  88        if (sparc_cpu_model == sun4m || sparc_cpu_model == sun4d)
  89                printk("%ld entries in page dir cache\n",pgd_cache_size);
  90#endif  
  91#endif
  92}
  93
  94void __init sparc_context_init(int numctx)
  95{
  96        int ctx;
  97
  98        ctx_list_pool = __alloc_bootmem(numctx * sizeof(struct ctx_list), SMP_CACHE_BYTES, 0UL);
  99
 100        for(ctx = 0; ctx < numctx; ctx++) {
 101                struct ctx_list *clist;
 102
 103                clist = (ctx_list_pool + ctx);
 104                clist->ctx_number = ctx;
 105                clist->ctx_mm = NULL;
 106        }
 107        ctx_free.next = ctx_free.prev = &ctx_free;
 108        ctx_used.next = ctx_used.prev = &ctx_used;
 109        for(ctx = 0; ctx < numctx; ctx++)
 110                add_to_free_ctxlist(ctx_list_pool + ctx);
 111}
 112
 113extern unsigned long cmdline_memory_size;
 114unsigned long last_valid_pfn;
 115
 116unsigned long calc_highpages(void)
 117{
 118        int i;
 119        int nr = 0;
 120
 121        for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 122                unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 123                unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 124
 125                if (end_pfn <= max_low_pfn)
 126                        continue;
 127
 128                if (start_pfn < max_low_pfn)
 129                        start_pfn = max_low_pfn;
 130
 131                nr += end_pfn - start_pfn;
 132        }
 133
 134        return nr;
 135}
 136
 137static unsigned long calc_max_low_pfn(void)
 138{
 139        int i;
 140        unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 141        unsigned long curr_pfn, last_pfn;
 142
 143        last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
 144        for (i = 1; sp_banks[i].num_bytes != 0; i++) {
 145                curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 146
 147                if (curr_pfn >= tmp) {
 148                        if (last_pfn < tmp)
 149                                tmp = last_pfn;
 150                        break;
 151                }
 152
 153                last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 154        }
 155
 156        return tmp;
 157}
 158
 159unsigned long __init bootmem_init(unsigned long *pages_avail)
 160{
 161        unsigned long bootmap_size, start_pfn;
 162        unsigned long end_of_phys_memory = 0UL;
 163        unsigned long bootmap_pfn, bytes_avail, size;
 164        int i;
 165
 166        bytes_avail = 0UL;
 167        for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 168                end_of_phys_memory = sp_banks[i].base_addr +
 169                        sp_banks[i].num_bytes;
 170                bytes_avail += sp_banks[i].num_bytes;
 171                if (cmdline_memory_size) {
 172                        if (bytes_avail > cmdline_memory_size) {
 173                                unsigned long slack = bytes_avail - cmdline_memory_size;
 174
 175                                bytes_avail -= slack;
 176                                end_of_phys_memory -= slack;
 177
 178                                sp_banks[i].num_bytes -= slack;
 179                                if (sp_banks[i].num_bytes == 0) {
 180                                        sp_banks[i].base_addr = 0xdeadbeef;
 181                                } else {
 182                                        sp_banks[i+1].num_bytes = 0;
 183                                        sp_banks[i+1].base_addr = 0xdeadbeef;
 184                                }
 185                                break;
 186                        }
 187                }
 188        }
 189
 190        /* Start with page aligned address of last symbol in kernel
 191         * image.  
 192         */
 193        start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
 194
 195        /* Now shift down to get the real physical page frame number. */
 196        start_pfn >>= PAGE_SHIFT;
 197
 198        bootmap_pfn = start_pfn;
 199
 200        max_pfn = end_of_phys_memory >> PAGE_SHIFT;
 201
 202        max_low_pfn = max_pfn;
 203        highstart_pfn = highend_pfn = max_pfn;
 204
 205        if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
 206                highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
 207                max_low_pfn = calc_max_low_pfn();
 208                printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 209                    calc_highpages() >> (20 - PAGE_SHIFT));
 210        }
 211
 212#ifdef CONFIG_BLK_DEV_INITRD
 213        /* Now have to check initial ramdisk, so that bootmap does not overwrite it */
 214        if (sparc_ramdisk_image) {
 215                if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
 216                        sparc_ramdisk_image -= KERNBASE;
 217                initrd_start = sparc_ramdisk_image + phys_base;
 218                initrd_end = initrd_start + sparc_ramdisk_size;
 219                if (initrd_end > end_of_phys_memory) {
 220                        printk(KERN_CRIT "initrd extends beyond end of memory "
 221                                         "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
 222                               initrd_end, end_of_phys_memory);
 223                        initrd_start = 0;
 224                }
 225                if (initrd_start) {
 226                        if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
 227                            initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
 228                                bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
 229                }
 230        }
 231#endif  
 232        /* Initialize the boot-time allocator. */
 233        bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
 234                                         max_low_pfn);
 235
 236        /* Now register the available physical memory with the
 237         * allocator.
 238         */
 239        *pages_avail = 0;
 240        for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 241                unsigned long curr_pfn, last_pfn;
 242
 243                curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 244                if (curr_pfn >= max_low_pfn)
 245                        break;
 246
 247                last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 248                if (last_pfn > max_low_pfn)
 249                        last_pfn = max_low_pfn;
 250
 251                /*
 252                 * .. finally, did all the rounding and playing
 253                 * around just make the area go away?
 254                 */
 255                if (last_pfn <= curr_pfn)
 256                        continue;
 257
 258                size = (last_pfn - curr_pfn) << PAGE_SHIFT;
 259                *pages_avail += last_pfn - curr_pfn;
 260
 261                free_bootmem(sp_banks[i].base_addr, size);
 262        }
 263
 264#ifdef CONFIG_BLK_DEV_INITRD
 265        if (initrd_start) {
 266                /* Reserve the initrd image area. */
 267                size = initrd_end - initrd_start;
 268                reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
 269                *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 270
 271                initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
 272                initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;            
 273        }
 274#endif
 275        /* Reserve the kernel text/data/bss. */
 276        size = (start_pfn << PAGE_SHIFT) - phys_base;
 277        reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
 278        *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 279
 280        /* Reserve the bootmem map.   We do not account for it
 281         * in pages_avail because we will release that memory
 282         * in free_all_bootmem.
 283         */
 284        size = bootmap_size;
 285        reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
 286        *pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
 287
 288        return max_pfn;
 289}
 290
 291/*
 292 * check_pgt_cache
 293 *
 294 * This is called at the end of unmapping of VMA (zap_page_range),
 295 * to rescan the page cache for architecture specific things,
 296 * presumably something like sun4/sun4c PMEGs. Most architectures
 297 * define check_pgt_cache empty.
 298 *
 299 * We simply copy the 2.4 implementation for now.
 300 */
 301static int pgt_cache_water[2] = { 25, 50 };
 302
 303void check_pgt_cache(void)
 304{
 305        do_check_pgt_cache(pgt_cache_water[0], pgt_cache_water[1]);
 306}
 307
 308/*
 309 * paging_init() sets up the page tables: We call the MMU specific
 310 * init routine based upon the Sun model type on the Sparc.
 311 *
 312 */
 313extern void sun4c_paging_init(void);
 314extern void srmmu_paging_init(void);
 315extern void device_scan(void);
 316
 317pgprot_t PAGE_SHARED __read_mostly;
 318EXPORT_SYMBOL(PAGE_SHARED);
 319
 320void __init paging_init(void)
 321{
 322        switch(sparc_cpu_model) {
 323        case sun4c:
 324        case sun4e:
 325        case sun4:
 326                sun4c_paging_init();
 327                sparc_unmapped_base = 0xe0000000;
 328                BTFIXUPSET_SETHI(sparc_unmapped_base, 0xe0000000);
 329                break;
 330        case sparc_leon:
 331                leon_init();
 332                /* fall through */
 333        case sun4m:
 334        case sun4d:
 335                srmmu_paging_init();
 336                sparc_unmapped_base = 0x50000000;
 337                BTFIXUPSET_SETHI(sparc_unmapped_base, 0x50000000);
 338                break;
 339        default:
 340                prom_printf("paging_init: Cannot init paging on this Sparc\n");
 341                prom_printf("paging_init: sparc_cpu_model = %d\n", sparc_cpu_model);
 342                prom_printf("paging_init: Halting...\n");
 343                prom_halt();
 344        };
 345
 346        /* Initialize the protection map with non-constant, MMU dependent values. */
 347        protection_map[0] = PAGE_NONE;
 348        protection_map[1] = PAGE_READONLY;
 349        protection_map[2] = PAGE_COPY;
 350        protection_map[3] = PAGE_COPY;
 351        protection_map[4] = PAGE_READONLY;
 352        protection_map[5] = PAGE_READONLY;
 353        protection_map[6] = PAGE_COPY;
 354        protection_map[7] = PAGE_COPY;
 355        protection_map[8] = PAGE_NONE;
 356        protection_map[9] = PAGE_READONLY;
 357        protection_map[10] = PAGE_SHARED;
 358        protection_map[11] = PAGE_SHARED;
 359        protection_map[12] = PAGE_READONLY;
 360        protection_map[13] = PAGE_READONLY;
 361        protection_map[14] = PAGE_SHARED;
 362        protection_map[15] = PAGE_SHARED;
 363        btfixup();
 364        prom_build_devicetree();
 365        of_fill_in_cpu_data();
 366        device_scan();
 367}
 368
 369static void __init taint_real_pages(void)
 370{
 371        int i;
 372
 373        for (i = 0; sp_banks[i].num_bytes; i++) {
 374                unsigned long start, end;
 375
 376                start = sp_banks[i].base_addr;
 377                end = start + sp_banks[i].num_bytes;
 378
 379                while (start < end) {
 380                        set_bit(start >> 20, sparc_valid_addr_bitmap);
 381                        start += PAGE_SIZE;
 382                }
 383        }
 384}
 385
 386static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
 387{
 388        unsigned long tmp;
 389
 390#ifdef CONFIG_DEBUG_HIGHMEM
 391        printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
 392#endif
 393
 394        for (tmp = start_pfn; tmp < end_pfn; tmp++) {
 395                struct page *page = pfn_to_page(tmp);
 396
 397                ClearPageReserved(page);
 398                init_page_count(page);
 399                __free_page(page);
 400                totalhigh_pages++;
 401        }
 402}
 403
 404void __init mem_init(void)
 405{
 406        int codepages = 0;
 407        int datapages = 0;
 408        int initpages = 0; 
 409        int reservedpages = 0;
 410        int i;
 411
 412        if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
 413                prom_printf("BUG: fixmap and pkmap areas overlap\n");
 414                prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
 415                       PKMAP_BASE,
 416                       (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
 417                       FIXADDR_START);
 418                prom_printf("Please mail sparclinux@vger.kernel.org.\n");
 419                prom_halt();
 420        }
 421
 422
 423        /* Saves us work later. */
 424        memset((void *)&empty_zero_page, 0, PAGE_SIZE);
 425
 426        i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
 427        i += 1;
 428        sparc_valid_addr_bitmap = (unsigned long *)
 429                __alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
 430
 431        if (sparc_valid_addr_bitmap == NULL) {
 432                prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
 433                prom_halt();
 434        }
 435        memset(sparc_valid_addr_bitmap, 0, i << 2);
 436
 437        taint_real_pages();
 438
 439        max_mapnr = last_valid_pfn - pfn_base;
 440        high_memory = __va(max_low_pfn << PAGE_SHIFT);
 441
 442        totalram_pages = free_all_bootmem();
 443
 444        for (i = 0; sp_banks[i].num_bytes != 0; i++) {
 445                unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
 446                unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
 447
 448                num_physpages += sp_banks[i].num_bytes >> PAGE_SHIFT;
 449
 450                if (end_pfn <= highstart_pfn)
 451                        continue;
 452
 453                if (start_pfn < highstart_pfn)
 454                        start_pfn = highstart_pfn;
 455
 456                map_high_region(start_pfn, end_pfn);
 457        }
 458        
 459        totalram_pages += totalhigh_pages;
 460
 461        codepages = (((unsigned long) &_etext) - ((unsigned long)&_start));
 462        codepages = PAGE_ALIGN(codepages) >> PAGE_SHIFT;
 463        datapages = (((unsigned long) &_edata) - ((unsigned long)&_etext));
 464        datapages = PAGE_ALIGN(datapages) >> PAGE_SHIFT;
 465        initpages = (((unsigned long) &__init_end) - ((unsigned long) &__init_begin));
 466        initpages = PAGE_ALIGN(initpages) >> PAGE_SHIFT;
 467
 468        /* Ignore memory holes for the purpose of counting reserved pages */
 469        for (i=0; i < max_low_pfn; i++)
 470                if (test_bit(i >> (20 - PAGE_SHIFT), sparc_valid_addr_bitmap)
 471                    && PageReserved(pfn_to_page(i)))
 472                        reservedpages++;
 473
 474        printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init, %ldk highmem)\n",
 475               nr_free_pages() << (PAGE_SHIFT-10),
 476               num_physpages << (PAGE_SHIFT - 10),
 477               codepages << (PAGE_SHIFT-10),
 478               reservedpages << (PAGE_SHIFT - 10),
 479               datapages << (PAGE_SHIFT-10), 
 480               initpages << (PAGE_SHIFT-10),
 481               totalhigh_pages << (PAGE_SHIFT-10));
 482}
 483
 484void free_initmem (void)
 485{
 486        unsigned long addr;
 487        unsigned long freed;
 488
 489        addr = (unsigned long)(&__init_begin);
 490        freed = (unsigned long)(&__init_end) - addr;
 491        for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
 492                struct page *p;
 493
 494                memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
 495                p = virt_to_page(addr);
 496
 497                ClearPageReserved(p);
 498                init_page_count(p);
 499                __free_page(p);
 500                totalram_pages++;
 501                num_physpages++;
 502        }
 503        printk(KERN_INFO "Freeing unused kernel memory: %ldk freed\n",
 504                freed >> 10);
 505}
 506
 507#ifdef CONFIG_BLK_DEV_INITRD
 508void free_initrd_mem(unsigned long start, unsigned long end)
 509{
 510        if (start < end)
 511                printk(KERN_INFO "Freeing initrd memory: %ldk freed\n",
 512                        (end - start) >> 10);
 513        for (; start < end; start += PAGE_SIZE) {
 514                struct page *p;
 515
 516                memset((void *)start, POISON_FREE_INITMEM, PAGE_SIZE);
 517                p = virt_to_page(start);
 518
 519                ClearPageReserved(p);
 520                init_page_count(p);
 521                __free_page(p);
 522                totalram_pages++;
 523                num_physpages++;
 524        }
 525}
 526#endif
 527
 528void sparc_flush_page_to_ram(struct page *page)
 529{
 530        unsigned long vaddr = (unsigned long)page_address(page);
 531
 532        if (vaddr)
 533                __flush_page_to_ram(vaddr);
 534}
 535EXPORT_SYMBOL(sparc_flush_page_to_ram);
 536