Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 | /*
* arch/xtensa/mm/init.c
*
* Derived from MIPS, PPC.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001 - 2005 Tensilica Inc.
*
* Chris Zankel <chris@zankel.net>
* Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
* Marc Gauthier
* Kevin Chea
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/bootmem.h>
#include <linux/swap.h>
#include <linux/mman.h>
#include <linux/nodemask.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <asm/pgtable.h>
#include <asm/bootparam.h>
#include <asm/mmu_context.h>
#include <asm/tlb.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
/* References to section boundaries */
extern char _ftext, _etext, _fdata, _edata, _rodata_end;
extern char __init_begin, __init_end;
/*
* mem_reserve(start, end, must_exist)
*
* Reserve some memory from the memory pool.
*
* Parameters:
* start Start of region,
* end End of region,
* must_exist Must exist in memory pool.
*
* Returns:
* 0 (memory area couldn't be mapped)
* -1 (success)
*/
int __init mem_reserve(unsigned long start, unsigned long end, int must_exist)
{
int i;
if (start == end)
return 0;
start = start & PAGE_MASK;
end = PAGE_ALIGN(end);
for (i = 0; i < sysmem.nr_banks; i++)
if (start < sysmem.bank[i].end
&& end >= sysmem.bank[i].start)
break;
if (i == sysmem.nr_banks) {
if (must_exist)
printk (KERN_WARNING "mem_reserve: [0x%0lx, 0x%0lx) "
"not in any region!\n", start, end);
return 0;
}
if (start > sysmem.bank[i].start) {
if (end < sysmem.bank[i].end) {
/* split entry */
if (sysmem.nr_banks >= SYSMEM_BANKS_MAX)
panic("meminfo overflow\n");
sysmem.bank[sysmem.nr_banks].start = end;
sysmem.bank[sysmem.nr_banks].end = sysmem.bank[i].end;
sysmem.nr_banks++;
}
sysmem.bank[i].end = start;
} else {
if (end < sysmem.bank[i].end)
sysmem.bank[i].start = end;
else {
/* remove entry */
sysmem.nr_banks--;
sysmem.bank[i].start = sysmem.bank[sysmem.nr_banks].start;
sysmem.bank[i].end = sysmem.bank[sysmem.nr_banks].end;
}
}
return -1;
}
/*
* Initialize the bootmem system and give it all the memory we have available.
*/
void __init bootmem_init(void)
{
unsigned long pfn;
unsigned long bootmap_start, bootmap_size;
int i;
max_low_pfn = max_pfn = 0;
min_low_pfn = ~0;
for (i=0; i < sysmem.nr_banks; i++) {
pfn = PAGE_ALIGN(sysmem.bank[i].start) >> PAGE_SHIFT;
if (pfn < min_low_pfn)
min_low_pfn = pfn;
pfn = PAGE_ALIGN(sysmem.bank[i].end - 1) >> PAGE_SHIFT;
if (pfn > max_pfn)
max_pfn = pfn;
}
if (min_low_pfn > max_pfn)
panic("No memory found!\n");
max_low_pfn = max_pfn < MAX_MEM_PFN >> PAGE_SHIFT ?
max_pfn : MAX_MEM_PFN >> PAGE_SHIFT;
/* Find an area to use for the bootmem bitmap. */
bootmap_size = bootmem_bootmap_pages(max_low_pfn) << PAGE_SHIFT;
bootmap_start = ~0;
for (i=0; i<sysmem.nr_banks; i++)
if (sysmem.bank[i].end - sysmem.bank[i].start >= bootmap_size) {
bootmap_start = sysmem.bank[i].start;
break;
}
if (bootmap_start == ~0UL)
panic("Cannot find %ld bytes for bootmap\n", bootmap_size);
/* Reserve the bootmem bitmap area */
mem_reserve(bootmap_start, bootmap_start + bootmap_size, 1);
bootmap_size = init_bootmem_node(NODE_DATA(0), min_low_pfn,
bootmap_start >> PAGE_SHIFT,
max_low_pfn);
/* Add all remaining memory pieces into the bootmem map */
for (i=0; i<sysmem.nr_banks; i++)
free_bootmem(sysmem.bank[i].start,
sysmem.bank[i].end - sysmem.bank[i].start);
}
void __init paging_init(void)
{
unsigned long zones_size[MAX_NR_ZONES];
int i;
/* All pages are DMA-able, so we put them all in the DMA zone. */
zones_size[ZONE_DMA] = max_low_pfn;
for (i = 1; i < MAX_NR_ZONES; i++)
zones_size[i] = 0;
#ifdef CONFIG_HIGHMEM
zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn;
#endif
/* Initialize the kernel's page tables. */
memset(swapper_pg_dir, 0, PAGE_SIZE);
free_area_init(zones_size);
}
/*
* Flush the mmu and reset associated register to default values.
*/
void __init init_mmu (void)
{
/* Writing zeros to the <t>TLBCFG special registers ensure
* that valid values exist in the register. For existing
* PGSZID<w> fields, zero selects the first element of the
* page-size array. For nonexistent PGSZID<w> fields, zero is
* the best value to write. Also, when changing PGSZID<w>
* fields, the corresponding TLB must be flushed.
*/
set_itlbcfg_register (0);
set_dtlbcfg_register (0);
flush_tlb_all ();
/* Set rasid register to a known value. */
set_rasid_register (ASID_USER_FIRST);
/* Set PTEVADDR special register to the start of the page
* table, which is in kernel mappable space (ie. not
* statically mapped). This register's value is undefined on
* reset.
*/
set_ptevaddr_register (PGTABLE_START);
}
/*
* Initialize memory pages.
*/
void __init mem_init(void)
{
unsigned long codesize, reservedpages, datasize, initsize;
unsigned long highmemsize, tmp, ram;
max_mapnr = num_physpages = max_low_pfn;
high_memory = (void *) __va(max_mapnr << PAGE_SHIFT);
highmemsize = 0;
#ifdef CONFIG_HIGHMEM
#error HIGHGMEM not implemented in init.c
#endif
totalram_pages += free_all_bootmem();
reservedpages = ram = 0;
for (tmp = 0; tmp < max_low_pfn; tmp++) {
ram++;
if (PageReserved(mem_map+tmp))
reservedpages++;
}
codesize = (unsigned long) &_etext - (unsigned long) &_ftext;
datasize = (unsigned long) &_edata - (unsigned long) &_fdata;
initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, "
"%ldk data, %ldk init %ldk highmem)\n",
(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
ram << (PAGE_SHIFT-10),
codesize >> 10,
reservedpages << (PAGE_SHIFT-10),
datasize >> 10,
initsize >> 10,
highmemsize >> 10);
}
void
free_reserved_mem(void *start, void *end)
{
for (; start < end; start += PAGE_SIZE) {
ClearPageReserved(virt_to_page(start));
init_page_count(virt_to_page(start));
free_page((unsigned long)start);
totalram_pages++;
}
}
#ifdef CONFIG_BLK_DEV_INITRD
extern int initrd_is_mapped;
void free_initrd_mem(unsigned long start, unsigned long end)
{
if (initrd_is_mapped) {
free_reserved_mem((void*)start, (void*)end);
printk ("Freeing initrd memory: %ldk freed\n",(end-start)>>10);
}
}
#endif
void free_initmem(void)
{
free_reserved_mem(&__init_begin, &__init_end);
printk("Freeing unused kernel memory: %dk freed\n",
(&__init_end - &__init_begin) >> 10);
}
void show_mem(void)
{
int i, free = 0, total = 0, reserved = 0;
int shared = 0, cached = 0;
printk("Mem-info:\n");
show_free_areas();
printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
i = max_mapnr;
while (i-- > 0) {
total++;
if (PageReserved(mem_map+i))
reserved++;
else if (PageSwapCache(mem_map+i))
cached++;
else if (!page_count(mem_map + i))
free++;
else
shared += page_count(mem_map + i) - 1;
}
printk("%d pages of RAM\n", total);
printk("%d reserved pages\n", reserved);
printk("%d pages shared\n", shared);
printk("%d pages swap cached\n",cached);
printk("%d free pages\n", free);
}
struct kmem_cache *pgtable_cache __read_mostly;
static void pgd_ctor(struct kmem_cache *cache, void* addr)
{
pte_t* ptep = (pte_t*)addr;
int i;
for (i = 0; i < 1024; i++, ptep++)
pte_clear(NULL, 0, ptep);
}
void __init pgtable_cache_init(void)
{
pgtable_cache = kmem_cache_create("pgd",
PAGE_SIZE, PAGE_SIZE,
SLAB_HWCACHE_ALIGN,
pgd_ctor);
}
|