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 | /*
* linux/arch/m68k/mm/motorola.c
*
* Routines specific to the Motorola MMU, originally from:
* linux/arch/m68k/init.c
* which are Copyright (C) 1995 Hamish Macdonald
*
* Moved 8/20/1999 Sam Creasey
*/
#include <linux/module.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/gfp.h>
#include <asm/setup.h>
#include <asm/uaccess.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/system.h>
#include <asm/machdep.h>
#include <asm/io.h>
#include <asm/dma.h>
#ifdef CONFIG_ATARI
#include <asm/atari_stram.h>
#endif
#include <asm/sections.h>
#undef DEBUG
#ifndef mm_cachebits
/*
* Bits to add to page descriptors for "normal" caching mode.
* For 68020/030 this is 0.
* For 68040, this is _PAGE_CACHE040 (cachable, copyback)
*/
unsigned long mm_cachebits;
EXPORT_SYMBOL(mm_cachebits);
#endif
/* size of memory already mapped in head.S */
#define INIT_MAPPED_SIZE (4UL<<20)
extern unsigned long availmem;
static pte_t * __init kernel_page_table(void)
{
pte_t *ptablep;
ptablep = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE);
clear_page(ptablep);
__flush_page_to_ram(ptablep);
flush_tlb_kernel_page(ptablep);
nocache_page(ptablep);
return ptablep;
}
static pmd_t *last_pgtable __initdata = NULL;
pmd_t *zero_pgtable __initdata = NULL;
static pmd_t * __init kernel_ptr_table(void)
{
if (!last_pgtable) {
unsigned long pmd, last;
int i;
/* Find the last ptr table that was used in head.S and
* reuse the remaining space in that page for further
* ptr tables.
*/
last = (unsigned long)kernel_pg_dir;
for (i = 0; i < PTRS_PER_PGD; i++) {
if (!pgd_present(kernel_pg_dir[i]))
continue;
pmd = __pgd_page(kernel_pg_dir[i]);
if (pmd > last)
last = pmd;
}
last_pgtable = (pmd_t *)last;
#ifdef DEBUG
printk("kernel_ptr_init: %p\n", last_pgtable);
#endif
}
last_pgtable += PTRS_PER_PMD;
if (((unsigned long)last_pgtable & ~PAGE_MASK) == 0) {
last_pgtable = (pmd_t *)alloc_bootmem_low_pages(PAGE_SIZE);
clear_page(last_pgtable);
__flush_page_to_ram(last_pgtable);
flush_tlb_kernel_page(last_pgtable);
nocache_page(last_pgtable);
}
return last_pgtable;
}
static void __init map_node(int node)
{
#define PTRTREESIZE (256*1024)
#define ROOTTREESIZE (32*1024*1024)
unsigned long physaddr, virtaddr, size;
pgd_t *pgd_dir;
pmd_t *pmd_dir;
pte_t *pte_dir;
size = m68k_memory[node].size;
physaddr = m68k_memory[node].addr;
virtaddr = (unsigned long)phys_to_virt(physaddr);
physaddr |= m68k_supervisor_cachemode |
_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY;
if (CPU_IS_040_OR_060)
physaddr |= _PAGE_GLOBAL040;
while (size > 0) {
#ifdef DEBUG
if (!(virtaddr & (PTRTREESIZE-1)))
printk ("\npa=%#lx va=%#lx ", physaddr & PAGE_MASK,
virtaddr);
#endif
pgd_dir = pgd_offset_k(virtaddr);
if (virtaddr && CPU_IS_020_OR_030) {
if (!(virtaddr & (ROOTTREESIZE-1)) &&
size >= ROOTTREESIZE) {
#ifdef DEBUG
printk ("[very early term]");
#endif
pgd_val(*pgd_dir) = physaddr;
size -= ROOTTREESIZE;
virtaddr += ROOTTREESIZE;
physaddr += ROOTTREESIZE;
continue;
}
}
if (!pgd_present(*pgd_dir)) {
pmd_dir = kernel_ptr_table();
#ifdef DEBUG
printk ("[new pointer %p]", pmd_dir);
#endif
pgd_set(pgd_dir, pmd_dir);
} else
pmd_dir = pmd_offset(pgd_dir, virtaddr);
if (CPU_IS_020_OR_030) {
if (virtaddr) {
#ifdef DEBUG
printk ("[early term]");
#endif
pmd_dir->pmd[(virtaddr/PTRTREESIZE) & 15] = physaddr;
physaddr += PTRTREESIZE;
} else {
int i;
#ifdef DEBUG
printk ("[zero map]");
#endif
zero_pgtable = kernel_ptr_table();
pte_dir = (pte_t *)zero_pgtable;
pmd_dir->pmd[0] = virt_to_phys(pte_dir) |
_PAGE_TABLE | _PAGE_ACCESSED;
pte_val(*pte_dir++) = 0;
physaddr += PAGE_SIZE;
for (i = 1; i < 64; physaddr += PAGE_SIZE, i++)
pte_val(*pte_dir++) = physaddr;
}
size -= PTRTREESIZE;
virtaddr += PTRTREESIZE;
} else {
if (!pmd_present(*pmd_dir)) {
#ifdef DEBUG
printk ("[new table]");
#endif
pte_dir = kernel_page_table();
pmd_set(pmd_dir, pte_dir);
}
pte_dir = pte_offset_kernel(pmd_dir, virtaddr);
if (virtaddr) {
if (!pte_present(*pte_dir))
pte_val(*pte_dir) = physaddr;
} else
pte_val(*pte_dir) = 0;
size -= PAGE_SIZE;
virtaddr += PAGE_SIZE;
physaddr += PAGE_SIZE;
}
}
#ifdef DEBUG
printk("\n");
#endif
}
/*
* paging_init() continues the virtual memory environment setup which
* was begun by the code in arch/head.S.
*/
void __init paging_init(void)
{
unsigned long zones_size[MAX_NR_ZONES] = { 0, };
unsigned long min_addr, max_addr;
unsigned long addr, size, end;
int i;
#ifdef DEBUG
printk ("start of paging_init (%p, %lx)\n", kernel_pg_dir, availmem);
#endif
/* Fix the cache mode in the page descriptors for the 680[46]0. */
if (CPU_IS_040_OR_060) {
int i;
#ifndef mm_cachebits
mm_cachebits = _PAGE_CACHE040;
#endif
for (i = 0; i < 16; i++)
pgprot_val(protection_map[i]) |= _PAGE_CACHE040;
}
min_addr = m68k_memory[0].addr;
max_addr = min_addr + m68k_memory[0].size;
for (i = 1; i < m68k_num_memory;) {
if (m68k_memory[i].addr < min_addr) {
printk("Ignoring memory chunk at 0x%lx:0x%lx before the first chunk\n",
m68k_memory[i].addr, m68k_memory[i].size);
printk("Fix your bootloader or use a memfile to make use of this area!\n");
m68k_num_memory--;
memmove(m68k_memory + i, m68k_memory + i + 1,
(m68k_num_memory - i) * sizeof(struct mem_info));
continue;
}
addr = m68k_memory[i].addr + m68k_memory[i].size;
if (addr > max_addr)
max_addr = addr;
i++;
}
m68k_memoffset = min_addr - PAGE_OFFSET;
m68k_virt_to_node_shift = fls(max_addr - min_addr - 1) - 6;
module_fixup(NULL, __start_fixup, __stop_fixup);
flush_icache();
high_memory = phys_to_virt(max_addr);
min_low_pfn = availmem >> PAGE_SHIFT;
max_low_pfn = max_addr >> PAGE_SHIFT;
for (i = 0; i < m68k_num_memory; i++) {
addr = m68k_memory[i].addr;
end = addr + m68k_memory[i].size;
m68k_setup_node(i);
availmem = PAGE_ALIGN(availmem);
availmem += init_bootmem_node(NODE_DATA(i),
availmem >> PAGE_SHIFT,
addr >> PAGE_SHIFT,
end >> PAGE_SHIFT);
}
/*
* Map the physical memory available into the kernel virtual
* address space. First initialize the bootmem allocator with
* the memory we already mapped, so map_node() has something
* to allocate.
*/
addr = m68k_memory[0].addr;
size = m68k_memory[0].size;
free_bootmem_node(NODE_DATA(0), availmem, min(INIT_MAPPED_SIZE, size) - (availmem - addr));
map_node(0);
if (size > INIT_MAPPED_SIZE)
free_bootmem_node(NODE_DATA(0), addr + INIT_MAPPED_SIZE, size - INIT_MAPPED_SIZE);
for (i = 1; i < m68k_num_memory; i++)
map_node(i);
flush_tlb_all();
/*
* initialize the bad page table and bad page to point
* to a couple of allocated pages
*/
empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
/*
* Set up SFC/DFC registers
*/
set_fs(KERNEL_DS);
#ifdef DEBUG
printk ("before free_area_init\n");
#endif
for (i = 0; i < m68k_num_memory; i++) {
zones_size[ZONE_DMA] = m68k_memory[i].size >> PAGE_SHIFT;
free_area_init_node(i, zones_size,
m68k_memory[i].addr >> PAGE_SHIFT, NULL);
if (node_present_pages(i))
node_set_state(i, N_NORMAL_MEMORY);
}
}
void free_initmem(void)
{
unsigned long addr;
addr = (unsigned long)__init_begin;
for (; addr < (unsigned long)__init_end; addr += PAGE_SIZE) {
virt_to_page(addr)->flags &= ~(1 << PG_reserved);
init_page_count(virt_to_page(addr));
free_page(addr);
totalram_pages++;
}
}
|