arch/powerpc/mm/init_64.c

   1 /*
   2  *  PowerPC version
   3  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   4  *
   5  *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
   6  *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
   7  *    Copyright (C) 1996 Paul Mackerras
   8  *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
   9  *
  10  *  Derived from "arch/i386/mm/init.c"
  11  *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
  12  *
  13  *  Dave Engebretsen <engebret@us.ibm.com>
  14  *      Rework for PPC64 port.
  15  *
  16  *  This program is free software; you can redistribute it and/or
  17  *  modify it under the terms of the GNU General Public License
  18  *  as published by the Free Software Foundation; either version
  19  *  2 of the License, or (at your option) any later version.
  20  *
  21  */
  22
  23 #include <linux/config.h>
  24 #include <linux/signal.h>
  25 #include <linux/sched.h>
  26 #include <linux/kernel.h>
  27 #include <linux/errno.h>
  28 #include <linux/string.h>
  29 #include <linux/types.h>
  30 #include <linux/mman.h>
  31 #include <linux/mm.h>
  32 #include <linux/swap.h>
  33 #include <linux/stddef.h>
  34 #include <linux/vmalloc.h>
  35 #include <linux/init.h>
  36 #include <linux/delay.h>
  37 #include <linux/bootmem.h>
  38 #include <linux/highmem.h>
  39 #include <linux/idr.h>
  40 #include <linux/nodemask.h>
  41 #include <linux/module.h>
  42
  43 #include <asm/pgalloc.h>
  44 #include <asm/page.h>
  45 #include <asm/prom.h>
  46 #include <asm/lmb.h>
  47 #include <asm/rtas.h>
  48 #include <asm/io.h>
  49 #include <asm/mmu_context.h>
  50 #include <asm/pgtable.h>
  51 #include <asm/mmu.h>
  52 #include <asm/uaccess.h>
  53 #include <asm/smp.h>
  54 #include <asm/machdep.h>
  55 #include <asm/tlb.h>
  56 #include <asm/eeh.h>
  57 #include <asm/processor.h>
  58 #include <asm/mmzone.h>
  59 #include <asm/cputable.h>
  60 #include <asm/ppcdebug.h>
  61 #include <asm/sections.h>
  62 #include <asm/system.h>
  63 #include <asm/iommu.h>
  64 #include <asm/abs_addr.h>
  65 #include <asm/vdso.h>
  66 #include <asm/imalloc.h>
  67
  68 #if PGTABLE_RANGE > USER_VSID_RANGE
  69 #warning Limited user VSID range means pagetable space is wasted
  70 #endif
  71
  72 #if (TASK_SIZE_USER64 < PGTABLE_RANGE) && (TASK_SIZE_USER64 < USER_VSID_RANGE)
  73 #warning TASK_SIZE is smaller than it needs to be.
  74 #endif
  75
  76 unsigned long klimit = (unsigned long)_end;
  77
  78 /* max amount of RAM to use */
  79 unsigned long __max_memory;
  80
  81 /* info on what we think the IO hole is */
  82 unsigned long   io_hole_start;
  83 unsigned long   io_hole_size;
  84
  85 /*
  86  * Do very early mm setup.
  87  */
  88 void __init mm_init_ppc64(void)
  89 {
  90 #ifndef CONFIG_PPC_ISERIES
  91         unsigned long i;
  92 #endif
  93
  94         ppc64_boot_msg(0x100, "MM Init");
  95
  96         /* This is the story of the IO hole... please, keep seated,
  97          * unfortunately, we are out of oxygen masks at the moment.
  98          * So we need some rough way to tell where your big IO hole
  99          * is. On pmac, it's between 2G and 4G, on POWER3, it's around
 100          * that area as well, on POWER4 we don't have one, etc...
 101          * We need that as a "hint" when sizing the TCE table on POWER3
 102          * So far, the simplest way that seem work well enough for us it
 103          * to just assume that the first discontinuity in our physical
 104          * RAM layout is the IO hole. That may not be correct in the future
 105          * (and isn't on iSeries but then we don't care ;)
 106          */
 107
 108 #ifndef CONFIG_PPC_ISERIES
 109         for (i = 1; i < lmb.memory.cnt; i++) {
 110                 unsigned long base, prevbase, prevsize;
 111
 112                 prevbase = lmb.memory.region[i-1].base;
 113                 prevsize = lmb.memory.region[i-1].size;
 114                 base = lmb.memory.region[i].base;
 115                 if (base > (prevbase + prevsize)) {
 116                         io_hole_start = prevbase + prevsize;
 117                         io_hole_size = base  - (prevbase + prevsize);
 118                         break;
 119                 }
 120         }
 121 #endif /* CONFIG_PPC_ISERIES */
 122         if (io_hole_start)
 123                 printk("IO Hole assumed to be %lx -> %lx\n",
 124                        io_hole_start, io_hole_start + io_hole_size - 1);
 125
 126         ppc64_boot_msg(0x100, "MM Init Done");
 127 }
 128
 129 void free_initmem(void)
 130 {
 131         unsigned long addr;
 132
 133         addr = (unsigned long)__init_begin;
 134         for (; addr < (unsigned long)__init_end; addr += PAGE_SIZE) {
 135                 memset((void *)addr, 0xcc, PAGE_SIZE);
 136                 ClearPageReserved(virt_to_page(addr));
 137                 set_page_count(virt_to_page(addr), 1);
 138                 free_page(addr);
 139                 totalram_pages++;
 140         }
 141         printk ("Freeing unused kernel memory: %luk freed\n",
 142                 ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10);
 143 }
 144
 145 #ifdef CONFIG_BLK_DEV_INITRD
 146 void free_initrd_mem(unsigned long start, unsigned long end)
 147 {
 148         if (start < end)
 149                 printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
 150         for (; start < end; start += PAGE_SIZE) {
 151                 ClearPageReserved(virt_to_page(start));
 152                 set_page_count(virt_to_page(start), 1);
 153                 free_page(start);
 154                 totalram_pages++;
 155         }
 156 }
 157 #endif
 158
 159 static struct kcore_list kcore_vmem;
 160
 161 static int __init setup_kcore(void)
 162 {
 163         int i;
 164
 165         for (i=0; i < lmb.memory.cnt; i++) {
 166                 unsigned long base, size;
 167                 struct kcore_list *kcore_mem;
 168
 169                 base = lmb.memory.region[i].base;
 170                 size = lmb.memory.region[i].size;
 171
 172                 /* GFP_ATOMIC to avoid might_sleep warnings during boot */
 173                 kcore_mem = kmalloc(sizeof(struct kcore_list), GFP_ATOMIC);
 174                 if (!kcore_mem)
 175                         panic("mem_init: kmalloc failed\n");
 176
 177                 kclist_add(kcore_mem, __va(base), size);
 178         }
 179
 180         kclist_add(&kcore_vmem, (void *)VMALLOC_START, VMALLOC_END-VMALLOC_START);
 181
 182         return 0;
 183 }
 184 module_init(setup_kcore);
 185
 186 static void zero_ctor(void *addr, kmem_cache_t *cache, unsigned long flags)
 187 {
 188         memset(addr, 0, kmem_cache_size(cache));
 189 }
 190
 191 #ifdef CONFIG_PPC_64K_PAGES
 192 static const int pgtable_cache_size[2] = {
 193         PTE_TABLE_SIZE, PGD_TABLE_SIZE
 194 };
 195 static const char *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
 196         "pte_pmd_cache", "pgd_cache",
 197 };
 198 #else
 199 static const int pgtable_cache_size[2] = {
 200         PTE_TABLE_SIZE, PMD_TABLE_SIZE
 201 };
 202 static const char *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
 203         "pgd_pte_cache", "pud_pmd_cache",
 204 };
 205 #endif /* CONFIG_PPC_64K_PAGES */
 206
 207 kmem_cache_t *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];
 208
 209 void pgtable_cache_init(void)
 210 {
 211         int i;
 212
 213         for (i = 0; i < ARRAY_SIZE(pgtable_cache_size); i++) {
 214                 int size = pgtable_cache_size[i];
 215                 const char *name = pgtable_cache_name[i];
 216
 217                 pgtable_cache[i] = kmem_cache_create(name,
 218                                                      size, size,
 219                                                      SLAB_HWCACHE_ALIGN |
 220                                                      SLAB_MUST_HWCACHE_ALIGN,
 221                                                      zero_ctor,
 222                                                      NULL);
 223                 if (! pgtable_cache[i])
 224                         panic("pgtable_cache_init(): could not create %s!\n",
 225                               name);
 226         }
 227 }