1 /* 2 * This file is subject to the terms and conditions of the GNU General Public 3 * License. See the file "COPYING" in the main directory of this archive 4 * for more details. 5 * 6 * Copyright (C) 1994 - 2000 Ralf Baechle 7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc. 8 * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com 9 * Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved. 10 */ 11 #include <linux/config.h> 12 #include <linux/init.h> 13 #include <linux/module.h> 14 #include <linux/signal.h> 15 #include <linux/sched.h> 16 #include <linux/kernel.h> 17 #include <linux/errno.h> 18 #include <linux/string.h> 19 #include <linux/types.h> 20 #include <linux/pagemap.h> 21 #include <linux/ptrace.h> 22 #include <linux/mman.h> 23 #include <linux/mm.h> 24 #include <linux/bootmem.h> 25 #include <linux/highmem.h> 26 #include <linux/swap.h> 27 28 #include <asm/bootinfo.h> 29 #include <asm/cachectl.h> 30 #include <asm/cpu.h> 31 #include <asm/dma.h> 32 #include <asm/mmu_context.h> 33 #include <asm/sections.h> 34 #include <asm/pgtable.h> 35 #include <asm/pgalloc.h> 36 #include <asm/tlb.h> 37 38 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); 39 40 unsigned long highstart_pfn, highend_pfn; 41 42 /* 43 * We have up to 8 empty zeroed pages so we can map one of the right colour 44 * when needed. This is necessary only on R4000 / R4400 SC and MC versions 45 * where we have to avoid VCED / VECI exceptions for good performance at 46 * any price. Since page is never written to after the initialization we 47 * don't have to care about aliases on other CPUs. 48 */ 49 unsigned long empty_zero_page, zero_page_mask; 50 51 /* 52 * Not static inline because used by IP27 special magic initialization code 53 */ 54 unsigned long setup_zero_pages(void) 55 { 56 unsigned long order, size; 57 struct page *page; 58 59 if (cpu_has_vce) 60 order = 3; 61 else 62 order = 0; 63 64 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 65 if (!empty_zero_page) 66 panic("Oh boy, that early out of memory?"); 67 68 page = virt_to_page(empty_zero_page); 69 while (page < virt_to_page(empty_zero_page + (PAGE_SIZE << order))) { 70 set_bit(PG_reserved, &page->flags); 71 set_page_count(page, 0); 72 page++; 73 } 74 75 size = PAGE_SIZE << order; 76 zero_page_mask = (size - 1) & PAGE_MASK; 77 78 return 1UL << order; 79 } 80 81 #ifdef CONFIG_HIGHMEM 82 pte_t *kmap_pte; 83 pgprot_t kmap_prot; 84 85 #define kmap_get_fixmap_pte(vaddr) \ 86 pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)) 87 88 static void __init kmap_init(void) 89 { 90 unsigned long kmap_vstart; 91 92 /* cache the first kmap pte */ 93 kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN); 94 kmap_pte = kmap_get_fixmap_pte(kmap_vstart); 95 96 kmap_prot = PAGE_KERNEL; 97 } 98 99 #ifdef CONFIG_64BIT 100 static void __init fixrange_init(unsigned long start, unsigned long end, 101 pgd_t *pgd_base) 102 { 103 pgd_t *pgd; 104 pmd_t *pmd; 105 pte_t *pte; 106 int i, j; 107 unsigned long vaddr; 108 109 vaddr = start; 110 i = __pgd_offset(vaddr); 111 j = __pmd_offset(vaddr); 112 pgd = pgd_base + i; 113 114 for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) { 115 pmd = (pmd_t *)pgd; 116 for (; (j < PTRS_PER_PMD) && (vaddr != end); pmd++, j++) { 117 if (pmd_none(*pmd)) { 118 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); 119 set_pmd(pmd, __pmd(pte)); 120 if (pte != pte_offset_kernel(pmd, 0)) 121 BUG(); 122 } 123 vaddr += PMD_SIZE; 124 } 125 j = 0; 126 } 127 } 128 #endif /* CONFIG_64BIT */ 129 #endif /* CONFIG_HIGHMEM */ 130 131 #ifndef CONFIG_NEED_MULTIPLE_NODES 132 extern void pagetable_init(void); 133 134 void __init paging_init(void) 135 { 136 unsigned long zones_size[MAX_NR_ZONES] = {0, 0, 0}; 137 unsigned long max_dma, high, low; 138 139 pagetable_init(); 140 141 #ifdef CONFIG_HIGHMEM 142 kmap_init(); 143 #endif 144 145 max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT; 146 low = max_low_pfn; 147 high = highend_pfn; 148 149 #ifdef CONFIG_ISA 150 if (low < max_dma) 151 zones_size[ZONE_DMA] = low; 152 else { 153 zones_size[ZONE_DMA] = max_dma; 154 zones_size[ZONE_NORMAL] = low - max_dma; 155 } 156 #else 157 zones_size[ZONE_DMA] = low; 158 #endif 159 #ifdef CONFIG_HIGHMEM 160 if (cpu_has_dc_aliases) { 161 printk(KERN_WARNING "This processor doesn't support highmem."); 162 if (high - low) 163 printk(" %ldk highmem ignored", high - low); 164 printk("\n"); 165 } else 166 zones_size[ZONE_HIGHMEM] = high - low; 167 #endif 168 169 free_area_init(zones_size); 170 } 171 172 #define PFN_UP(x) (((x) + PAGE_SIZE - 1) >> PAGE_SHIFT) 173 #define PFN_DOWN(x) ((x) >> PAGE_SHIFT) 174 175 static inline int page_is_ram(unsigned long pagenr) 176 { 177 int i; 178 179 for (i = 0; i < boot_mem_map.nr_map; i++) { 180 unsigned long addr, end; 181 182 if (boot_mem_map.map[i].type != BOOT_MEM_RAM) 183 /* not usable memory */ 184 continue; 185 186 addr = PFN_UP(boot_mem_map.map[i].addr); 187 end = PFN_DOWN(boot_mem_map.map[i].addr + 188 boot_mem_map.map[i].size); 189 190 if (pagenr >= addr && pagenr < end) 191 return 1; 192 } 193 194 return 0; 195 } 196 197 void __init mem_init(void) 198 { 199 unsigned long codesize, reservedpages, datasize, initsize; 200 unsigned long tmp, ram; 201 202 #ifdef CONFIG_HIGHMEM 203 #ifdef CONFIG_DISCONTIGMEM 204 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet" 205 #endif 206 max_mapnr = num_physpages = highend_pfn; 207 #else 208 max_mapnr = num_physpages = max_low_pfn; 209 #endif 210 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); 211 212 totalram_pages += free_all_bootmem(); 213 totalram_pages -= setup_zero_pages(); /* Setup zeroed pages. */ 214 215 reservedpages = ram = 0; 216 for (tmp = 0; tmp < max_low_pfn; tmp++) 217 if (page_is_ram(tmp)) { 218 ram++; 219 if (PageReserved(mem_map+tmp)) 220 reservedpages++; 221 } 222 223 #ifdef CONFIG_HIGHMEM 224 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) { 225 struct page *page = mem_map + tmp; 226 227 if (!page_is_ram(tmp)) { 228 SetPageReserved(page); 229 continue; 230 } 231 ClearPageReserved(page); 232 #ifdef CONFIG_LIMITED_DMA 233 set_page_address(page, lowmem_page_address(page)); 234 #endif 235 set_page_count(page, 1); 236 __free_page(page); 237 totalhigh_pages++; 238 } 239 totalram_pages += totalhigh_pages; 240 #endif 241 242 codesize = (unsigned long) &_etext - (unsigned long) &_text; 243 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 244 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 245 246 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, " 247 "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n", 248 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 249 ram << (PAGE_SHIFT-10), 250 codesize >> 10, 251 reservedpages << (PAGE_SHIFT-10), 252 datasize >> 10, 253 initsize >> 10, 254 (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10))); 255 } 256 #endif /* !CONFIG_NEED_MULTIPLE_NODES */ 257 258 #ifdef CONFIG_BLK_DEV_INITRD 259 void free_initrd_mem(unsigned long start, unsigned long end) 260 { 261 #ifdef CONFIG_64BIT 262 /* Switch from KSEG0 to XKPHYS addresses */ 263 start = (unsigned long)phys_to_virt(CPHYSADDR(start)); 264 end = (unsigned long)phys_to_virt(CPHYSADDR(end)); 265 #endif 266 if (start < end) 267 printk(KERN_INFO "Freeing initrd memory: %ldk freed\n", 268 (end - start) >> 10); 269 270 for (; start < end; start += PAGE_SIZE) { 271 ClearPageReserved(virt_to_page(start)); 272 set_page_count(virt_to_page(start), 1); 273 free_page(start); 274 totalram_pages++; 275 } 276 } 277 #endif 278 279 extern unsigned long prom_free_prom_memory(void); 280 281 void free_initmem(void) 282 { 283 unsigned long addr, page, freed; 284 285 freed = prom_free_prom_memory(); 286 287 addr = (unsigned long) &__init_begin; 288 while (addr < (unsigned long) &__init_end) { 289 #ifdef CONFIG_64BIT 290 page = PAGE_OFFSET | CPHYSADDR(addr); 291 #else 292 page = addr; 293 #endif 294 ClearPageReserved(virt_to_page(page)); 295 set_page_count(virt_to_page(page), 1); 296 free_page(page); 297 totalram_pages++; 298 freed += PAGE_SIZE; 299 addr += PAGE_SIZE; 300 } 301 printk(KERN_INFO "Freeing unused kernel memory: %ldk freed\n", 302 freed >> 10); 303 } 304