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 <asm/mmu_context.h>
  19 #include <asm/tlb.h>
  20 #include <asm/cacheflush.h>
  21 #include <asm/sections.h>
  22 #include <asm/cache.h>
  23
  24 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  25 pgd_t swapper_pg_dir[PTRS_PER_PGD];
  26
  27 void (*copy_page)(void *from, void *to);
  28 void (*clear_page)(void *to);
  29
  30 void show_mem(void)
  31 {
  32         int total = 0, reserved = 0, free = 0;
  33         int shared = 0, cached = 0, slab = 0;
  34         pg_data_t *pgdat;
  35
  36         printk("Mem-info:\n");
  37         show_free_areas();
  38
  39         for_each_online_pgdat(pgdat) {
  40                 unsigned long flags, i;
  41
  42                 pgdat_resize_lock(pgdat, &flags);
  43                 for (i = 0; i < pgdat->node_spanned_pages; i++) {
  44                         struct page *page = pgdat_page_nr(pgdat, i);
  45                         total++;
  46                         if (PageReserved(page))
  47                                 reserved++;
  48                         else if (PageSwapCache(page))
  49                                 cached++;
  50                         else if (PageSlab(page))
  51                                 slab++;
  52                         else if (!page_count(page))
  53                                 free++;
  54                         else
  55                                 shared += page_count(page) - 1;
  56                 }
  57                 pgdat_resize_unlock(pgdat, &flags);
  58         }
  59
  60         printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
  61         printk("%d pages of RAM\n", total);
  62         printk("%d free pages\n", free);
  63         printk("%d reserved pages\n", reserved);
  64         printk("%d slab pages\n", slab);
  65         printk("%d pages shared\n", shared);
  66         printk("%d pages swap cached\n", cached);
  67         printk(KERN_INFO "Total of %ld pages in page table cache\n",
  68                quicklist_total_size());
  69 }
  70
  71 #ifdef CONFIG_MMU
  72 static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot)
  73 {
  74         pgd_t *pgd;
  75         pud_t *pud;
  76         pmd_t *pmd;
  77         pte_t *pte;
  78
  79         pgd = pgd_offset_k(addr);
  80         if (pgd_none(*pgd)) {
  81                 pgd_ERROR(*pgd);
  82                 return;
  83         }
  84
  85         pud = pud_alloc(NULL, pgd, addr);
  86         if (unlikely(!pud)) {
  87                 pud_ERROR(*pud);
  88                 return;
  89         }
  90
  91         pmd = pmd_alloc(NULL, pud, addr);
  92         if (unlikely(!pmd)) {
  93                 pmd_ERROR(*pmd);
  94                 return;
  95         }
  96
  97         pte = pte_offset_kernel(pmd, addr);
  98         if (!pte_none(*pte)) {
  99                 pte_ERROR(*pte);
 100                 return;
 101         }
 102
 103         set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot));
 104
 105         flush_tlb_one(get_asid(), addr);
 106 }
 107
 108 /*
 109  * As a performance optimization, other platforms preserve the fixmap mapping
 110  * across a context switch, we don't presently do this, but this could be done
 111  * in a similar fashion as to the wired TLB interface that sh64 uses (by way
 112  * of the memory mapped UTLB configuration) -- this unfortunately forces us to
 113  * give up a TLB entry for each mapping we want to preserve. While this may be
 114  * viable for a small number of fixmaps, it's not particularly useful for
 115  * everything and needs to be carefully evaluated. (ie, we may want this for
 116  * the vsyscall page).
 117  *
 118  * XXX: Perhaps add a _PAGE_WIRED flag or something similar that we can pass
 119  * in at __set_fixmap() time to determine the appropriate behavior to follow.
 120  *
 121  *                                       -- PFM.
 122  */
 123 void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
 124 {
 125         unsigned long address = __fix_to_virt(idx);
 126
 127         if (idx >= __end_of_fixed_addresses) {
 128                 BUG();
 129                 return;
 130         }
 131
 132         set_pte_phys(address, phys, prot);
 133 }
 134 #endif  /* CONFIG_MMU */
 135
 136 /*
 137  * paging_init() sets up the page tables
 138  */
 139 void __init paging_init(void)
 140 {
 141         unsigned long max_zone_pfns[MAX_NR_ZONES];
 142         int nid;
 143
 144         /* We don't need to map the kernel through the TLB, as
 145          * it is permanatly mapped using P1. So clear the
 146          * entire pgd. */
 147         memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
 148
 149         /* Set an initial value for the MMU.TTB so we don't have to
 150          * check for a null value. */
 151         set_TTB(swapper_pg_dir);
 152
 153         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
 154
 155         for_each_online_node(nid) {
 156                 pg_data_t *pgdat = NODE_DATA(nid);
 157                 unsigned long low, start_pfn;
 158
 159                 start_pfn = pgdat->bdata->node_boot_start >> PAGE_SHIFT;
 160                 low = pgdat->bdata->node_low_pfn;
 161
 162                 if (max_zone_pfns[ZONE_NORMAL] < low)
 163                         max_zone_pfns[ZONE_NORMAL] = low;
 164
 165                 printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
 166                        nid, start_pfn, low);
 167         }
 168
 169         free_area_init_nodes(max_zone_pfns);
 170 }
 171
 172 static struct kcore_list kcore_mem, kcore_vmalloc;
 173
 174 void __init mem_init(void)
 175 {
 176         int codesize, datasize, initsize;
 177         int nid;
 178
 179         num_physpages = 0;
 180         high_memory = NULL;
 181
 182         for_each_online_node(nid) {
 183                 pg_data_t *pgdat = NODE_DATA(nid);
 184                 unsigned long node_pages = 0;
 185                 void *node_high_memory;
 186
 187                 num_physpages += pgdat->node_present_pages;
 188
 189                 if (pgdat->node_spanned_pages)
 190                         node_pages = free_all_bootmem_node(pgdat);
 191
 192                 totalram_pages += node_pages;
 193
 194                 node_high_memory = (void *)__va((pgdat->node_start_pfn +
 195                                                  pgdat->node_spanned_pages) <<
 196                                                  PAGE_SHIFT);
 197                 if (node_high_memory > high_memory)
 198                         high_memory = node_high_memory;
 199         }
 200
 201         /* clear the zero-page */
 202         memset(empty_zero_page, 0, PAGE_SIZE);
 203         __flush_wback_region(empty_zero_page, PAGE_SIZE);
 204
 205         /*
 206          * Setup wrappers for copy/clear_page(), these will get overridden
 207          * later in the boot process if a better method is available.
 208          */
 209 #ifdef CONFIG_MMU
 210         copy_page = copy_page_slow;
 211         clear_page = clear_page_slow;
 212 #else
 213         copy_page = copy_page_nommu;
 214         clear_page = clear_page_nommu;
 215 #endif
 216
 217         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
 218         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
 219         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
 220
 221         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
 222         kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
 223                    VMALLOC_END - VMALLOC_START);
 224
 225         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, "
 226                "%dk data, %dk init)\n",
 227                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 228                 num_physpages << (PAGE_SHIFT-10),
 229                 codesize >> 10,
 230                 datasize >> 10,
 231                 initsize >> 10);
 232
 233         p3_cache_init();
 234
 235         /* Initialize the vDSO */
 236         vsyscall_init();
 237 }
 238
 239 void free_initmem(void)
 240 {
 241         unsigned long addr;
 242
 243         addr = (unsigned long)(&__init_begin);
 244         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
 245                 ClearPageReserved(virt_to_page(addr));
 246                 init_page_count(virt_to_page(addr));
 247                 free_page(addr);
 248                 totalram_pages++;
 249         }
 250         printk("Freeing unused kernel memory: %ldk freed\n",
 251                ((unsigned long)&__init_end -
 252                 (unsigned long)&__init_begin) >> 10);
 253 }
 254
 255 #ifdef CONFIG_BLK_DEV_INITRD
 256 void free_initrd_mem(unsigned long start, unsigned long end)
 257 {
 258         unsigned long p;
 259         for (p = start; p < end; p += PAGE_SIZE) {
 260                 ClearPageReserved(virt_to_page(p));
 261                 init_page_count(virt_to_page(p));
 262                 free_page(p);
 263                 totalram_pages++;
 264         }
 265         printk("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
 266 }
 267 #endif
 268
 269 #ifdef CONFIG_MEMORY_HOTPLUG
 270 void online_page(struct page *page)
 271 {
 272         ClearPageReserved(page);
 273         init_page_count(page);
 274         __free_page(page);
 275         totalram_pages++;
 276         num_physpages++;
 277 }
 278
 279 int arch_add_memory(int nid, u64 start, u64 size)
 280 {
 281         pg_data_t *pgdat;
 282         unsigned long start_pfn = start >> PAGE_SHIFT;
 283         unsigned long nr_pages = size >> PAGE_SHIFT;
 284         int ret;
 285
 286         pgdat = NODE_DATA(nid);
 287
 288         /* We only have ZONE_NORMAL, so this is easy.. */
 289         ret = __add_pages(pgdat->node_zones + ZONE_NORMAL, start_pfn, nr_pages);
 290         if (unlikely(ret))
 291                 printk("%s: Failed, __add_pages() == %d\n", __FUNCTION__, ret);
 292
 293         return ret;
 294 }
 295 EXPORT_SYMBOL_GPL(arch_add_memory);
 296
 297 #ifdef CONFIG_NUMA
 298 int memory_add_physaddr_to_nid(u64 addr)
 299 {
 300         /* Node 0 for now.. */
 301         return 0;
 302 }
 303 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
 304 #endif
 305 #endif