arch/sh/mm/init.c

   1 /*
   2  * linux/arch/sh/mm/init.c
   3  *
   4  *  Copyright (C) 1999  Niibe Yutaka
   5  *  Copyright (C) 2002 - 2007  Paul Mundt
   6  *
   7  *  Based on linux/arch/i386/mm/init.c:
   8  *   Copyright (C) 1995  Linus Torvalds
   9  */
  10 #include <linux/mm.h>
  11 #include <linux/swap.h>
  12 #include <linux/init.h>
  13 #include <linux/bootmem.h>
  14 #include <linux/proc_fs.h>
  15 #include <linux/pagemap.h>
  16 #include <linux/percpu.h>
  17 #include <linux/io.h>
  18 #include <linux/dma-mapping.h>
  19 #include <asm/mmu_context.h>
  20 #include <asm/tlb.h>
  21 #include <asm/cacheflush.h>
  22 #include <asm/sections.h>
  23 #include <asm/cache.h>
  24
  25 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  26 pgd_t swapper_pg_dir[PTRS_PER_PGD];
  27
  28 #ifdef CONFIG_SUPERH32
  29 /*
  30  * This is the offset of the uncached section from its cached alias.
  31  *
  32  * Legacy platforms handle trivial transitions between cached and
  33  * uncached segments by making use of the 1:1 mapping relationship in
  34  * 512MB lowmem, others via a special uncached mapping.
  35  *
  36  * Default value only valid in 29 bit mode, in 32bit mode this will be
  37  * updated by the early PMB initialization code.
  38  */
  39 unsigned long cached_to_uncached = P2SEG - P1SEG;
  40 unsigned long uncached_size = 0x20000000;
  41 #endif
  42
  43 #ifdef CONFIG_MMU
  44 static pte_t *__get_pte_phys(unsigned long addr)
  45 {
  46         pgd_t *pgd;
  47         pud_t *pud;
  48         pmd_t *pmd;
  49         pte_t *pte;
  50
  51         pgd = pgd_offset_k(addr);
  52         if (pgd_none(*pgd)) {
  53                 pgd_ERROR(*pgd);
  54                 return NULL;
  55         }
  56
  57         pud = pud_alloc(NULL, pgd, addr);
  58         if (unlikely(!pud)) {
  59                 pud_ERROR(*pud);
  60                 return NULL;
  61         }
  62
  63         pmd = pmd_alloc(NULL, pud, addr);
  64         if (unlikely(!pmd)) {
  65                 pmd_ERROR(*pmd);
  66                 return NULL;
  67         }
  68
  69         pte = pte_offset_kernel(pmd, addr);
  70         return pte;
  71 }
  72
  73 static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot)
  74 {
  75         pte_t *pte;
  76
  77         pte = __get_pte_phys(addr);
  78         if (!pte_none(*pte)) {
  79                 pte_ERROR(*pte);
  80                 return;
  81         }
  82
  83         set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot));
  84         local_flush_tlb_one(get_asid(), addr);
  85
  86         if (pgprot_val(prot) & _PAGE_WIRED)
  87                 tlb_wire_entry(NULL, addr, *pte);
  88 }
  89
  90 static void clear_pte_phys(unsigned long addr, pgprot_t prot)
  91 {
  92         pte_t *pte;
  93
  94         pte = __get_pte_phys(addr);
  95
  96         if (pgprot_val(prot) & _PAGE_WIRED)
  97                 tlb_unwire_entry();
  98
  99         set_pte(pte, pfn_pte(0, __pgprot(0)));
 100         local_flush_tlb_one(get_asid(), addr);
 101 }
 102
 103 void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
 104 {
 105         unsigned long address = __fix_to_virt(idx);
 106
 107         if (idx >= __end_of_fixed_addresses) {
 108                 BUG();
 109                 return;
 110         }
 111
 112         set_pte_phys(address, phys, prot);
 113 }
 114
 115 void __clear_fixmap(enum fixed_addresses idx, pgprot_t prot)
 116 {
 117         unsigned long address = __fix_to_virt(idx);
 118
 119         if (idx >= __end_of_fixed_addresses) {
 120                 BUG();
 121                 return;
 122         }
 123
 124         clear_pte_phys(address, prot);
 125 }
 126
 127 void __init page_table_range_init(unsigned long start, unsigned long end,
 128                                          pgd_t *pgd_base)
 129 {
 130         pgd_t *pgd;
 131         pud_t *pud;
 132         pmd_t *pmd;
 133         pte_t *pte;
 134         int i, j, k;
 135         unsigned long vaddr;
 136
 137         vaddr = start;
 138         i = __pgd_offset(vaddr);
 139         j = __pud_offset(vaddr);
 140         k = __pmd_offset(vaddr);
 141         pgd = pgd_base + i;
 142
 143         for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
 144                 pud = (pud_t *)pgd;
 145                 for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
 146 #ifdef __PAGETABLE_PMD_FOLDED
 147                         pmd = (pmd_t *)pud;
 148 #else
 149                         pmd = (pmd_t *)alloc_bootmem_low_pages(PAGE_SIZE);
 150                         pud_populate(&init_mm, pud, pmd);
 151                         pmd += k;
 152 #endif
 153                         for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
 154                                 if (pmd_none(*pmd)) {
 155                                         pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
 156                                         pmd_populate_kernel(&init_mm, pmd, pte);
 157                                         BUG_ON(pte != pte_offset_kernel(pmd, 0));
 158                                 }
 159                                 vaddr += PMD_SIZE;
 160                         }
 161                         k = 0;
 162                 }
 163                 j = 0;
 164         }
 165 }
 166 #endif  /* CONFIG_MMU */
 167
 168 /*
 169  * paging_init() sets up the page tables
 170  */
 171 void __init paging_init(void)
 172 {
 173         unsigned long max_zone_pfns[MAX_NR_ZONES];
 174         unsigned long vaddr, end;
 175         int nid;
 176
 177         /* We don't need to map the kernel through the TLB, as
 178          * it is permanatly mapped using P1. So clear the
 179          * entire pgd. */
 180         memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
 181
 182         /* Set an initial value for the MMU.TTB so we don't have to
 183          * check for a null value. */
 184         set_TTB(swapper_pg_dir);
 185
 186         /*
 187          * Populate the relevant portions of swapper_pg_dir so that
 188          * we can use the fixmap entries without calling kmalloc.
 189          * pte's will be filled in by __set_fixmap().
 190          */
 191         vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
 192         end = (FIXADDR_TOP + PMD_SIZE - 1) & PMD_MASK;
 193         page_table_range_init(vaddr, end, swapper_pg_dir);
 194
 195         kmap_coherent_init();
 196
 197         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
 198
 199         for_each_online_node(nid) {
 200                 pg_data_t *pgdat = NODE_DATA(nid);
 201                 unsigned long low, start_pfn;
 202
 203                 start_pfn = pgdat->bdata->node_min_pfn;
 204                 low = pgdat->bdata->node_low_pfn;
 205
 206                 if (max_zone_pfns[ZONE_NORMAL] < low)
 207                         max_zone_pfns[ZONE_NORMAL] = low;
 208
 209                 printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
 210                        nid, start_pfn, low);
 211         }
 212
 213         free_area_init_nodes(max_zone_pfns);
 214 }
 215
 216 /*
 217  * Early initialization for any I/O MMUs we might have.
 218  */
 219 static void __init iommu_init(void)
 220 {
 221         no_iommu_init();
 222 }
 223
 224 unsigned int mem_init_done = 0;
 225
 226 void __init mem_init(void)
 227 {
 228         int codesize, datasize, initsize;
 229         int nid;
 230
 231         iommu_init();
 232
 233         num_physpages = 0;
 234         high_memory = NULL;
 235
 236         for_each_online_node(nid) {
 237                 pg_data_t *pgdat = NODE_DATA(nid);
 238                 unsigned long node_pages = 0;
 239                 void *node_high_memory;
 240
 241                 num_physpages += pgdat->node_present_pages;
 242
 243                 if (pgdat->node_spanned_pages)
 244                         node_pages = free_all_bootmem_node(pgdat);
 245
 246                 totalram_pages += node_pages;
 247
 248                 node_high_memory = (void *)__va((pgdat->node_start_pfn +
 249                                                  pgdat->node_spanned_pages) <<
 250                                                  PAGE_SHIFT);
 251                 if (node_high_memory > high_memory)
 252                         high_memory = node_high_memory;
 253         }
 254
 255         /* Set this up early, so we can take care of the zero page */
 256         cpu_cache_init();
 257
 258         /* clear the zero-page */
 259         memset(empty_zero_page, 0, PAGE_SIZE);
 260         __flush_wback_region(empty_zero_page, PAGE_SIZE);
 261
 262         /* Initialize the vDSO */
 263         vsyscall_init();
 264
 265         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
 266         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
 267         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
 268
 269         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, "
 270                "%dk data, %dk init)\n",
 271                 nr_free_pages() << (PAGE_SHIFT-10),
 272                 num_physpages << (PAGE_SHIFT-10),
 273                 codesize >> 10,
 274                 datasize >> 10,
 275                 initsize >> 10);
 276
 277         printk(KERN_INFO "virtual kernel memory layout:\n"
 278                 "    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 279 #ifdef CONFIG_HIGHMEM
 280                 "    pkmap   : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 281 #endif
 282                 "    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
 283                 "    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB) (cached)\n"
 284                 "            : 0x%08lx - 0x%08lx   (%4ld MB) (uncached)\n"
 285                 "      .init : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 286                 "      .data : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 287                 "      .text : 0x%08lx - 0x%08lx   (%4ld kB)\n",
 288                 FIXADDR_START, FIXADDR_TOP,
 289                 (FIXADDR_TOP - FIXADDR_START) >> 10,
 290
 291 #ifdef CONFIG_HIGHMEM
 292                 PKMAP_BASE, PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
 293                 (LAST_PKMAP*PAGE_SIZE) >> 10,
 294 #endif
 295
 296                 (unsigned long)VMALLOC_START, VMALLOC_END,
 297                 (VMALLOC_END - VMALLOC_START) >> 20,
 298
 299                 (unsigned long)memory_start, (unsigned long)high_memory,
 300                 ((unsigned long)high_memory - (unsigned long)memory_start) >> 20,
 301
 302                 (unsigned long)memory_start + cached_to_uncached,
 303                 (unsigned long)memory_start + cached_to_uncached + uncached_size,
 304                 uncached_size >> 20,
 305
 306                 (unsigned long)&__init_begin, (unsigned long)&__init_end,
 307                 ((unsigned long)&__init_end -
 308                  (unsigned long)&__init_begin) >> 10,
 309
 310                 (unsigned long)&_etext, (unsigned long)&_edata,
 311                 ((unsigned long)&_edata - (unsigned long)&_etext) >> 10,
 312
 313                 (unsigned long)&_text, (unsigned long)&_etext,
 314                 ((unsigned long)&_etext - (unsigned long)&_text) >> 10);
 315
 316         mem_init_done = 1;
 317 }
 318
 319 void free_initmem(void)
 320 {
 321         unsigned long addr;
 322
 323         addr = (unsigned long)(&__init_begin);
 324         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
 325                 ClearPageReserved(virt_to_page(addr));
 326                 init_page_count(virt_to_page(addr));
 327                 free_page(addr);
 328                 totalram_pages++;
 329         }
 330         printk("Freeing unused kernel memory: %ldk freed\n",
 331                ((unsigned long)&__init_end -
 332                 (unsigned long)&__init_begin) >> 10);
 333 }
 334
 335 #ifdef CONFIG_BLK_DEV_INITRD
 336 void free_initrd_mem(unsigned long start, unsigned long end)
 337 {
 338         unsigned long p;
 339         for (p = start; p < end; p += PAGE_SIZE) {
 340                 ClearPageReserved(virt_to_page(p));
 341                 init_page_count(virt_to_page(p));
 342                 free_page(p);
 343                 totalram_pages++;
 344         }
 345         printk("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
 346 }
 347 #endif
 348
 349 #ifdef CONFIG_MEMORY_HOTPLUG
 350 int arch_add_memory(int nid, u64 start, u64 size)
 351 {
 352         pg_data_t *pgdat;
 353         unsigned long start_pfn = start >> PAGE_SHIFT;
 354         unsigned long nr_pages = size >> PAGE_SHIFT;
 355         int ret;
 356
 357         pgdat = NODE_DATA(nid);
 358
 359         /* We only have ZONE_NORMAL, so this is easy.. */
 360         ret = __add_pages(nid, pgdat->node_zones + ZONE_NORMAL,
 361                                 start_pfn, nr_pages);
 362         if (unlikely(ret))
 363                 printk("%s: Failed, __add_pages() == %d\n", __func__, ret);
 364
 365         return ret;
 366 }
 367 EXPORT_SYMBOL_GPL(arch_add_memory);
 368
 369 #ifdef CONFIG_NUMA
 370 int memory_add_physaddr_to_nid(u64 addr)
 371 {
 372         /* Node 0 for now.. */
 373         return 0;
 374 }
 375 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
 376 #endif
 377
 378 #endif /* CONFIG_MEMORY_HOTPLUG */