arch/microblaze/mm/init.c

   1 /*
   2  * Copyright (C) 2007-2008 Michal Simek <monstr@monstr.eu>
   3  * Copyright (C) 2006 Atmark Techno, Inc.
   4  *
   5  * This file is subject to the terms and conditions of the GNU General Public
   6  * License. See the file "COPYING" in the main directory of this archive
   7  * for more details.
   8  */
   9
  10 #include <linux/bootmem.h>
  11 #include <linux/init.h>
  12 #include <linux/kernel.h>
  13 #include <linux/memblock.h>
  14 #include <linux/mm.h> /* mem_init */
  15 #include <linux/initrd.h>
  16 #include <linux/pagemap.h>
  17 #include <linux/pfn.h>
  18 #include <linux/slab.h>
  19 #include <linux/swap.h>
  20 #include <linux/export.h>
  21
  22 #include <asm/page.h>
  23 #include <asm/mmu_context.h>
  24 #include <asm/pgalloc.h>
  25 #include <asm/sections.h>
  26 #include <asm/tlb.h>
  27 #include <asm/fixmap.h>
  28
  29 /* Use for MMU and noMMU because of PCI generic code */
  30 int mem_init_done;
  31
  32 #ifndef CONFIG_MMU
  33 unsigned int __page_offset;
  34 EXPORT_SYMBOL(__page_offset);
  35
  36 #else
  37 static int init_bootmem_done;
  38 #endif /* CONFIG_MMU */
  39
  40 char *klimit = _end;
  41
  42 /*
  43  * Initialize the bootmem system and give it all the memory we
  44  * have available.
  45  */
  46 unsigned long memory_start;
  47 EXPORT_SYMBOL(memory_start);
  48 unsigned long memory_size;
  49 EXPORT_SYMBOL(memory_size);
  50 unsigned long lowmem_size;
  51
  52 #ifdef CONFIG_HIGHMEM
  53 pte_t *kmap_pte;
  54 EXPORT_SYMBOL(kmap_pte);
  55 pgprot_t kmap_prot;
  56 EXPORT_SYMBOL(kmap_prot);
  57
  58 static inline pte_t *virt_to_kpte(unsigned long vaddr)
  59 {
  60         return pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr),
  61                         vaddr), vaddr);
  62 }
  63
  64 static void __init highmem_init(void)
  65 {
  66         pr_debug("%x\n", (u32)PKMAP_BASE);
  67         map_page(PKMAP_BASE, 0, 0);     /* XXX gross */
  68         pkmap_page_table = virt_to_kpte(PKMAP_BASE);
  69
  70         kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
  71         kmap_prot = PAGE_KERNEL;
  72 }
  73
  74 static unsigned long highmem_setup(void)
  75 {
  76         unsigned long pfn;
  77         unsigned long reservedpages = 0;
  78
  79         for (pfn = max_low_pfn; pfn < max_pfn; ++pfn) {
  80                 struct page *page = pfn_to_page(pfn);
  81
  82                 /* FIXME not sure about */
  83                 if (memblock_is_reserved(pfn << PAGE_SHIFT))
  84                         continue;
  85                 ClearPageReserved(page);
  86                 init_page_count(page);
  87                 __free_page(page);
  88                 totalhigh_pages++;
  89                 reservedpages++;
  90         }
  91         totalram_pages += totalhigh_pages;
  92         printk(KERN_INFO "High memory: %luk\n",
  93                                         totalhigh_pages << (PAGE_SHIFT-10));
  94
  95         return reservedpages;
  96 }
  97 #endif /* CONFIG_HIGHMEM */
  98
  99 /*
 100  * paging_init() sets up the page tables - in fact we've already done this.
 101  */
 102 static void __init paging_init(void)
 103 {
 104         unsigned long zones_size[MAX_NR_ZONES];
 105 #ifdef CONFIG_MMU
 106         int idx;
 107
 108         /* Setup fixmaps */
 109         for (idx = 0; idx < __end_of_fixed_addresses; idx++)
 110                 clear_fixmap(idx);
 111 #endif
 112
 113         /* Clean every zones */
 114         memset(zones_size, 0, sizeof(zones_size));
 115
 116 #ifdef CONFIG_HIGHMEM
 117         highmem_init();
 118
 119         zones_size[ZONE_DMA] = max_low_pfn;
 120         zones_size[ZONE_HIGHMEM] = max_pfn;
 121 #else
 122         zones_size[ZONE_DMA] = max_pfn;
 123 #endif
 124
 125         /* We don't have holes in memory map */
 126         free_area_init_nodes(zones_size);
 127 }
 128
 129 void __init setup_memory(void)
 130 {
 131         unsigned long map_size;
 132         struct memblock_region *reg;
 133
 134 #ifndef CONFIG_MMU
 135         u32 kernel_align_start, kernel_align_size;
 136
 137         /* Find main memory where is the kernel */
 138         for_each_memblock(memory, reg) {
 139                 memory_start = (u32)reg->base;
 140                 lowmem_size = reg->size;
 141                 if ((memory_start <= (u32)_text) &&
 142                         ((u32)_text <= (memory_start + lowmem_size - 1))) {
 143                         memory_size = lowmem_size;
 144                         PAGE_OFFSET = memory_start;
 145                         printk(KERN_INFO "%s: Main mem: 0x%x, "
 146                                 "size 0x%08x\n", __func__, (u32) memory_start,
 147                                         (u32) memory_size);
 148                         break;
 149                 }
 150         }
 151
 152         if (!memory_start || !memory_size) {
 153                 panic("%s: Missing memory setting 0x%08x, size=0x%08x\n",
 154                         __func__, (u32) memory_start, (u32) memory_size);
 155         }
 156
 157         /* reservation of region where is the kernel */
 158         kernel_align_start = PAGE_DOWN((u32)_text);
 159         /* ALIGN can be remove because _end in vmlinux.lds.S is align */
 160         kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start;
 161         printk(KERN_INFO "%s: kernel addr:0x%08x-0x%08x size=0x%08x\n",
 162                 __func__, kernel_align_start, kernel_align_start
 163                         + kernel_align_size, kernel_align_size);
 164         memblock_reserve(kernel_align_start, kernel_align_size);
 165 #endif
 166         /*
 167          * Kernel:
 168          * start: base phys address of kernel - page align
 169          * end: base phys address of kernel - page align
 170          *
 171          * min_low_pfn - the first page (mm/bootmem.c - node_boot_start)
 172          * max_low_pfn
 173          * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn)
 174          * num_physpages - number of all pages
 175          */
 176
 177         /* memory start is from the kernel end (aligned) to higher addr */
 178         min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */
 179         /* RAM is assumed contiguous */
 180         num_physpages = max_mapnr = memory_size >> PAGE_SHIFT;
 181         max_low_pfn = ((u64)memory_start + (u64)lowmem_size) >> PAGE_SHIFT;
 182         max_pfn = ((u64)memory_start + (u64)memory_size) >> PAGE_SHIFT;
 183
 184         printk(KERN_INFO "%s: max_mapnr: %#lx\n", __func__, max_mapnr);
 185         printk(KERN_INFO "%s: min_low_pfn: %#lx\n", __func__, min_low_pfn);
 186         printk(KERN_INFO "%s: max_low_pfn: %#lx\n", __func__, max_low_pfn);
 187         printk(KERN_INFO "%s: max_pfn: %#lx\n", __func__, max_pfn);
 188
 189         /*
 190          * Find an area to use for the bootmem bitmap.
 191          * We look for the first area which is at least
 192          * 128kB in length (128kB is enough for a bitmap
 193          * for 4GB of memory, using 4kB pages), plus 1 page
 194          * (in case the address isn't page-aligned).
 195          */
 196         map_size = init_bootmem_node(NODE_DATA(0),
 197                 PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn);
 198         memblock_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size);
 199
 200         /* Add active regions with valid PFNs */
 201         for_each_memblock(memory, reg) {
 202                 unsigned long start_pfn, end_pfn;
 203
 204                 start_pfn = memblock_region_memory_base_pfn(reg);
 205                 end_pfn = memblock_region_memory_end_pfn(reg);
 206                 memblock_set_node(start_pfn << PAGE_SHIFT,
 207                                         (end_pfn - start_pfn) << PAGE_SHIFT, 0);
 208         }
 209
 210         /* free bootmem is whole main memory */
 211         free_bootmem_with_active_regions(0, max_low_pfn);
 212
 213         /* reserve allocate blocks */
 214         for_each_memblock(reserved, reg) {
 215                 unsigned long top = reg->base + reg->size - 1;
 216
 217                 pr_debug("reserved - 0x%08x-0x%08x, %lx, %lx\n",
 218                          (u32) reg->base, (u32) reg->size, top,
 219                                                 memory_start + lowmem_size - 1);
 220
 221                 if (top <= (memory_start + lowmem_size - 1)) {
 222                         reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
 223                 } else if (reg->base < (memory_start + lowmem_size - 1)) {
 224                         unsigned long trunc_size = memory_start + lowmem_size -
 225                                                                 reg->base;
 226                         reserve_bootmem(reg->base, trunc_size, BOOTMEM_DEFAULT);
 227                 }
 228         }
 229
 230         /* XXX need to clip this if using highmem? */
 231         sparse_memory_present_with_active_regions(0);
 232
 233 #ifdef CONFIG_MMU
 234         init_bootmem_done = 1;
 235 #endif
 236         paging_init();
 237 }
 238
 239 void free_init_pages(char *what, unsigned long begin, unsigned long end)
 240 {
 241         unsigned long addr;
 242
 243         for (addr = begin; addr < end; addr += PAGE_SIZE) {
 244                 ClearPageReserved(virt_to_page(addr));
 245                 init_page_count(virt_to_page(addr));
 246                 free_page(addr);
 247                 totalram_pages++;
 248         }
 249         printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
 250 }
 251
 252 #ifdef CONFIG_BLK_DEV_INITRD
 253 void free_initrd_mem(unsigned long start, unsigned long end)
 254 {
 255         int pages = 0;
 256         for (; start < end; start += PAGE_SIZE) {
 257                 ClearPageReserved(virt_to_page(start));
 258                 init_page_count(virt_to_page(start));
 259                 free_page(start);
 260                 totalram_pages++;
 261                 pages++;
 262         }
 263         printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n",
 264                                         (int)(pages * (PAGE_SIZE / 1024)));
 265 }
 266 #endif
 267
 268 void free_initmem(void)
 269 {
 270         free_init_pages("unused kernel memory",
 271                         (unsigned long)(&__init_begin),
 272                         (unsigned long)(&__init_end));
 273 }
 274
 275 void __init mem_init(void)
 276 {
 277         pg_data_t *pgdat;
 278         unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize;
 279
 280         high_memory = (void *)__va(memory_start + lowmem_size - 1);
 281
 282         /* this will put all memory onto the freelists */
 283         totalram_pages += free_all_bootmem();
 284
 285         for_each_online_pgdat(pgdat) {
 286                 unsigned long i;
 287                 struct page *page;
 288
 289                 for (i = 0; i < pgdat->node_spanned_pages; i++) {
 290                         if (!pfn_valid(pgdat->node_start_pfn + i))
 291                                 continue;
 292                         page = pgdat_page_nr(pgdat, i);
 293                         if (PageReserved(page))
 294                                 reservedpages++;
 295                 }
 296         }
 297
 298 #ifdef CONFIG_HIGHMEM
 299         reservedpages -= highmem_setup();
 300 #endif
 301
 302         codesize = (unsigned long)&_sdata - (unsigned long)&_stext;
 303         datasize = (unsigned long)&_edata - (unsigned long)&_sdata;
 304         initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin;
 305         bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start;
 306
 307         pr_info("Memory: %luk/%luk available (%luk kernel code, "
 308                 "%luk reserved, %luk data, %luk bss, %luk init)\n",
 309                 nr_free_pages() << (PAGE_SHIFT-10),
 310                 num_physpages << (PAGE_SHIFT-10),
 311                 codesize >> 10,
 312                 reservedpages << (PAGE_SHIFT-10),
 313                 datasize >> 10,
 314                 bsssize >> 10,
 315                 initsize >> 10);
 316
 317 #ifdef CONFIG_MMU
 318         pr_info("Kernel virtual memory layout:\n");
 319         pr_info("  * 0x%08lx..0x%08lx  : fixmap\n", FIXADDR_START, FIXADDR_TOP);
 320 #ifdef CONFIG_HIGHMEM
 321         pr_info("  * 0x%08lx..0x%08lx  : highmem PTEs\n",
 322                 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
 323 #endif /* CONFIG_HIGHMEM */
 324         pr_info("  * 0x%08lx..0x%08lx  : early ioremap\n",
 325                 ioremap_bot, ioremap_base);
 326         pr_info("  * 0x%08lx..0x%08lx  : vmalloc & ioremap\n",
 327                 (unsigned long)VMALLOC_START, VMALLOC_END);
 328 #endif
 329         mem_init_done = 1;
 330 }
 331
 332 #ifndef CONFIG_MMU
 333 int page_is_ram(unsigned long pfn)
 334 {
 335         return __range_ok(pfn, 0);
 336 }
 337 #else
 338 int page_is_ram(unsigned long pfn)
 339 {
 340         return pfn < max_low_pfn;
 341 }
 342
 343 /*
 344  * Check for command-line options that affect what MMU_init will do.
 345  */
 346 static void mm_cmdline_setup(void)
 347 {
 348         unsigned long maxmem = 0;
 349         char *p = cmd_line;
 350
 351         /* Look for mem= option on command line */
 352         p = strstr(cmd_line, "mem=");
 353         if (p) {
 354                 p += 4;
 355                 maxmem = memparse(p, &p);
 356                 if (maxmem && memory_size > maxmem) {
 357                         memory_size = maxmem;
 358                         memblock.memory.regions[0].size = memory_size;
 359                 }
 360         }
 361 }
 362
 363 /*
 364  * MMU_init_hw does the chip-specific initialization of the MMU hardware.
 365  */
 366 static void __init mmu_init_hw(void)
 367 {
 368         /*
 369          * The Zone Protection Register (ZPR) defines how protection will
 370          * be applied to every page which is a member of a given zone. At
 371          * present, we utilize only two of the zones.
 372          * The zone index bits (of ZSEL) in the PTE are used for software
 373          * indicators, except the LSB.  For user access, zone 1 is used,
 374          * for kernel access, zone 0 is used.  We set all but zone 1
 375          * to zero, allowing only kernel access as indicated in the PTE.
 376          * For zone 1, we set a 01 binary (a value of 10 will not work)
 377          * to allow user access as indicated in the PTE.  This also allows
 378          * kernel access as indicated in the PTE.
 379          */
 380         __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \
 381                         "mts rzpr, r11;"
 382                         : : : "r11");
 383 }
 384
 385 /*
 386  * MMU_init sets up the basic memory mappings for the kernel,
 387  * including both RAM and possibly some I/O regions,
 388  * and sets up the page tables and the MMU hardware ready to go.
 389  */
 390
 391 /* called from head.S */
 392 asmlinkage void __init mmu_init(void)
 393 {
 394         unsigned int kstart, ksize;
 395
 396         if (!memblock.reserved.cnt) {
 397                 printk(KERN_EMERG "Error memory count\n");
 398                 machine_restart(NULL);
 399         }
 400
 401         if ((u32) memblock.memory.regions[0].size < 0x400000) {
 402                 printk(KERN_EMERG "Memory must be greater than 4MB\n");
 403                 machine_restart(NULL);
 404         }
 405
 406         if ((u32) memblock.memory.regions[0].size < kernel_tlb) {
 407                 printk(KERN_EMERG "Kernel size is greater than memory node\n");
 408                 machine_restart(NULL);
 409         }
 410
 411         /* Find main memory where the kernel is */
 412         memory_start = (u32) memblock.memory.regions[0].base;
 413         lowmem_size = memory_size = (u32) memblock.memory.regions[0].size;
 414
 415         if (lowmem_size > CONFIG_LOWMEM_SIZE) {
 416                 lowmem_size = CONFIG_LOWMEM_SIZE;
 417 #ifndef CONFIG_HIGHMEM
 418                 memory_size = lowmem_size;
 419 #endif
 420         }
 421
 422         mm_cmdline_setup(); /* FIXME parse args from command line - not used */
 423
 424         /*
 425          * Map out the kernel text/data/bss from the available physical
 426          * memory.
 427          */
 428         kstart = __pa(CONFIG_KERNEL_START); /* kernel start */
 429         /* kernel size */
 430         ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START));
 431         memblock_reserve(kstart, ksize);
 432
 433 #if defined(CONFIG_BLK_DEV_INITRD)
 434         /* Remove the init RAM disk from the available memory. */
 435 /*      if (initrd_start) {
 436                 mem_pieces_remove(&phys_avail, __pa(initrd_start),
 437                                   initrd_end - initrd_start, 1);
 438         }*/
 439 #endif /* CONFIG_BLK_DEV_INITRD */
 440
 441         /* Initialize the MMU hardware */
 442         mmu_init_hw();
 443
 444         /* Map in all of RAM starting at CONFIG_KERNEL_START */
 445         mapin_ram();
 446
 447         /* Extend vmalloc and ioremap area as big as possible */
 448 #ifdef CONFIG_HIGHMEM
 449         ioremap_base = ioremap_bot = PKMAP_BASE;
 450 #else
 451         ioremap_base = ioremap_bot = FIXADDR_START;
 452 #endif
 453
 454         /* Initialize the context management stuff */
 455         mmu_context_init();
 456
 457         /* Shortly after that, the entire linear mapping will be available */
 458         /* This will also cause that unflatten device tree will be allocated
 459          * inside 768MB limit */
 460         memblock_set_current_limit(memory_start + lowmem_size - 1);
 461 }
 462
 463 /* This is only called until mem_init is done. */
 464 void __init *early_get_page(void)
 465 {
 466         void *p;
 467         if (init_bootmem_done) {
 468                 p = alloc_bootmem_pages(PAGE_SIZE);
 469         } else {
 470                 /*
 471                  * Mem start + kernel_tlb -> here is limit
 472                  * because of mem mapping from head.S
 473                  */
 474                 p = __va(memblock_alloc_base(PAGE_SIZE, PAGE_SIZE,
 475                                         memory_start + kernel_tlb));
 476         }
 477         return p;
 478 }
 479
 480 #endif /* CONFIG_MMU */
 481
 482 void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask)
 483 {
 484         if (mem_init_done)
 485                 return kmalloc(size, mask);
 486         else
 487                 return alloc_bootmem(size);
 488 }
 489
 490 void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask)
 491 {
 492         void *p;
 493
 494         if (mem_init_done)
 495                 p = kzalloc(size, mask);
 496         else {
 497                 p = alloc_bootmem(size);
 498                 if (p)
 499                         memset(p, 0, size);
 500         }
 501         return p;
 502 }