arch/unicore32/mm/init.c

   1 /*
   2  *  linux/arch/unicore32/mm/init.c
   3  *
   4  *  Copyright (C) 2010 GUAN Xue-tao
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10 #include <linux/kernel.h>
  11 #include <linux/errno.h>
  12 #include <linux/swap.h>
  13 #include <linux/init.h>
  14 #include <linux/memblock.h>
  15 #include <linux/mman.h>
  16 #include <linux/nodemask.h>
  17 #include <linux/initrd.h>
  18 #include <linux/highmem.h>
  19 #include <linux/gfp.h>
  20 #include <linux/sort.h>
  21 #include <linux/dma-mapping.h>
  22 #include <linux/export.h>
  23
  24 #include <asm/sections.h>
  25 #include <asm/setup.h>
  26 #include <asm/sizes.h>
  27 #include <asm/tlb.h>
  28 #include <asm/memblock.h>
  29 #include <mach/map.h>
  30
  31 #include "mm.h"
  32
  33 /*
  34  * This keeps memory configuration data used by a couple memory
  35  * initialization functions, as well as show_mem() for the skipping
  36  * of holes in the memory map.  It is populated by uc32_add_memory().
  37  */
  38 struct meminfo meminfo;
  39
  40 static void __init find_limits(unsigned long *min, unsigned long *max_low,
  41         unsigned long *max_high)
  42 {
  43         struct meminfo *mi = &meminfo;
  44         int i;
  45
  46         *min = -1UL;
  47         *max_low = *max_high = 0;
  48
  49         for_each_bank(i, mi) {
  50                 struct membank *bank = &mi->bank[i];
  51                 unsigned long start, end;
  52
  53                 start = bank_pfn_start(bank);
  54                 end = bank_pfn_end(bank);
  55
  56                 if (*min > start)
  57                         *min = start;
  58                 if (*max_high < end)
  59                         *max_high = end;
  60                 if (bank->highmem)
  61                         continue;
  62                 if (*max_low < end)
  63                         *max_low = end;
  64         }
  65 }
  66
  67 static void __init uc32_bootmem_free(unsigned long min, unsigned long max_low,
  68         unsigned long max_high)
  69 {
  70         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
  71         struct memblock_region *reg;
  72
  73         /*
  74          * initialise the zones.
  75          */
  76         memset(zone_size, 0, sizeof(zone_size));
  77
  78         /*
  79          * The memory size has already been determined.  If we need
  80          * to do anything fancy with the allocation of this memory
  81          * to the zones, now is the time to do it.
  82          */
  83         zone_size[0] = max_low - min;
  84
  85         /*
  86          * Calculate the size of the holes.
  87          *  holes = node_size - sum(bank_sizes)
  88          */
  89         memcpy(zhole_size, zone_size, sizeof(zhole_size));
  90         for_each_memblock(memory, reg) {
  91                 unsigned long start = memblock_region_memory_base_pfn(reg);
  92                 unsigned long end = memblock_region_memory_end_pfn(reg);
  93
  94                 if (start < max_low) {
  95                         unsigned long low_end = min(end, max_low);
  96                         zhole_size[0] -= low_end - start;
  97                 }
  98         }
  99
 100         /*
 101          * Adjust the sizes according to any special requirements for
 102          * this machine type.
 103          */
 104         arch_adjust_zones(zone_size, zhole_size);
 105
 106         free_area_init_node(0, zone_size, min, zhole_size);
 107 }
 108
 109 int pfn_valid(unsigned long pfn)
 110 {
 111         return memblock_is_memory(pfn << PAGE_SHIFT);
 112 }
 113 EXPORT_SYMBOL(pfn_valid);
 114
 115 static void uc32_memory_present(void)
 116 {
 117 }
 118
 119 static int __init meminfo_cmp(const void *_a, const void *_b)
 120 {
 121         const struct membank *a = _a, *b = _b;
 122         long cmp = bank_pfn_start(a) - bank_pfn_start(b);
 123         return cmp < 0 ? -1 : cmp > 0 ? 1 : 0;
 124 }
 125
 126 void __init uc32_memblock_init(struct meminfo *mi)
 127 {
 128         int i;
 129
 130         sort(&meminfo.bank, meminfo.nr_banks, sizeof(meminfo.bank[0]),
 131                 meminfo_cmp, NULL);
 132
 133         for (i = 0; i < mi->nr_banks; i++)
 134                 memblock_add(mi->bank[i].start, mi->bank[i].size);
 135
 136         /* Register the kernel text, kernel data and initrd with memblock. */
 137         memblock_reserve(__pa(_text), _end - _text);
 138
 139 #ifdef CONFIG_BLK_DEV_INITRD
 140         if (!phys_initrd_size) {
 141                 phys_initrd_start = 0x01000000;
 142                 phys_initrd_size = SZ_8M;
 143         }
 144
 145         if (phys_initrd_size) {
 146                 memblock_reserve(phys_initrd_start, phys_initrd_size);
 147
 148                 /* Now convert initrd to virtual addresses */
 149                 initrd_start = __phys_to_virt(phys_initrd_start);
 150                 initrd_end = initrd_start + phys_initrd_size;
 151         }
 152 #endif
 153
 154         uc32_mm_memblock_reserve();
 155
 156         memblock_allow_resize();
 157         memblock_dump_all();
 158 }
 159
 160 void __init bootmem_init(void)
 161 {
 162         unsigned long min, max_low, max_high;
 163
 164         max_low = max_high = 0;
 165
 166         find_limits(&min, &max_low, &max_high);
 167
 168         node_set_online(0);
 169
 170         /*
 171          * Sparsemem tries to allocate bootmem in memory_present(),
 172          * so must be done after the fixed reservations
 173          */
 174         uc32_memory_present();
 175
 176         /*
 177          * sparse_init() needs the bootmem allocator up and running.
 178          */
 179         sparse_init();
 180
 181         /*
 182          * Now free the memory - free_area_init_node needs
 183          * the sparse mem_map arrays initialized by sparse_init()
 184          * for memmap_init_zone(), otherwise all PFNs are invalid.
 185          */
 186         uc32_bootmem_free(min, max_low, max_high);
 187
 188         high_memory = __va((max_low << PAGE_SHIFT) - 1) + 1;
 189
 190         /*
 191          * This doesn't seem to be used by the Linux memory manager any
 192          * more, but is used by ll_rw_block.  If we can get rid of it, we
 193          * also get rid of some of the stuff above as well.
 194          *
 195          * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
 196          * the system, not the maximum PFN.
 197          */
 198         max_low_pfn = max_low - PHYS_PFN_OFFSET;
 199         max_pfn = max_high - PHYS_PFN_OFFSET;
 200 }
 201
 202 static inline void
 203 free_memmap(unsigned long start_pfn, unsigned long end_pfn)
 204 {
 205         struct page *start_pg, *end_pg;
 206         unsigned long pg, pgend;
 207
 208         /*
 209          * Convert start_pfn/end_pfn to a struct page pointer.
 210          */
 211         start_pg = pfn_to_page(start_pfn - 1) + 1;
 212         end_pg = pfn_to_page(end_pfn);
 213
 214         /*
 215          * Convert to physical addresses, and
 216          * round start upwards and end downwards.
 217          */
 218         pg = PAGE_ALIGN(__pa(start_pg));
 219         pgend = __pa(end_pg) & PAGE_MASK;
 220
 221         /*
 222          * If there are free pages between these,
 223          * free the section of the memmap array.
 224          */
 225         if (pg < pgend)
 226                 memblock_free(pg, pgend - pg);
 227 }
 228
 229 /*
 230  * The mem_map array can get very big.  Free the unused area of the memory map.
 231  */
 232 static void __init free_unused_memmap(struct meminfo *mi)
 233 {
 234         unsigned long bank_start, prev_bank_end = 0;
 235         unsigned int i;
 236
 237         /*
 238          * This relies on each bank being in address order.
 239          * The banks are sorted previously in bootmem_init().
 240          */
 241         for_each_bank(i, mi) {
 242                 struct membank *bank = &mi->bank[i];
 243
 244                 bank_start = bank_pfn_start(bank);
 245
 246                 /*
 247                  * If we had a previous bank, and there is a space
 248                  * between the current bank and the previous, free it.
 249                  */
 250                 if (prev_bank_end && prev_bank_end < bank_start)
 251                         free_memmap(prev_bank_end, bank_start);
 252
 253                 /*
 254                  * Align up here since the VM subsystem insists that the
 255                  * memmap entries are valid from the bank end aligned to
 256                  * MAX_ORDER_NR_PAGES.
 257                  */
 258                 prev_bank_end = ALIGN(bank_pfn_end(bank), MAX_ORDER_NR_PAGES);
 259         }
 260 }
 261
 262 /*
 263  * mem_init() marks the free areas in the mem_map and tells us how much
 264  * memory is free.  This is done after various parts of the system have
 265  * claimed their memory after the kernel image.
 266  */
 267 void __init mem_init(void)
 268 {
 269         max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
 270
 271         free_unused_memmap(&meminfo);
 272
 273         /* this will put all unused low memory onto the freelists */
 274         memblock_free_all();
 275
 276         mem_init_print_info(NULL);
 277
 278         BUILD_BUG_ON(TASK_SIZE                          > MODULES_VADDR);
 279         BUG_ON(TASK_SIZE                                > MODULES_VADDR);
 280
 281         if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
 282                 /*
 283                  * On a machine this small we won't get
 284                  * anywhere without overcommit, so turn
 285                  * it on by default.
 286                  */
 287                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 288         }
 289 }
 290
 291 void free_initmem(void)
 292 {
 293         free_initmem_default(-1);
 294 }
 295
 296 #ifdef CONFIG_BLK_DEV_INITRD
 297
 298 static int keep_initrd;
 299
 300 void free_initrd_mem(unsigned long start, unsigned long end)
 301 {
 302         if (!keep_initrd)
 303                 free_reserved_area((void *)start, (void *)end, -1, "initrd");
 304 }
 305
 306 static int __init keepinitrd_setup(char *__unused)
 307 {
 308         keep_initrd = 1;
 309         return 1;
 310 }
 311
 312 __setup("keepinitrd", keepinitrd_setup);
 313 #endif