| 1 | /* |
| 2 | * arch/ubicom32/mm/init.c |
| 3 | * Ubicom32 architecture virtual memory initialization. |
| 4 | * |
| 5 | * (C) Copyright 2009, Ubicom, Inc. |
| 6 | * Copyright (C) 1998 D. Jeff Dionne <jeff@lineo.ca>, |
| 7 | * Kenneth Albanowski <kjahds@kjahds.com>, |
| 8 | * Copyright (C) 2000 Lineo, Inc. (www.lineo.com) |
| 9 | * |
| 10 | * Based on: |
| 11 | * |
| 12 | * linux/arch/m68k/mm/init.c |
| 13 | * |
| 14 | * Copyright (C) 1995 Hamish Macdonald |
| 15 | * |
| 16 | * JAN/1999 -- hacked to support ColdFire (gerg@snapgear.com) |
| 17 | * DEC/2000 -- linux 2.4 support <davidm@snapgear.com> |
| 18 | * |
| 19 | * This file is part of the Ubicom32 Linux Kernel Port. |
| 20 | * |
| 21 | * The Ubicom32 Linux Kernel Port is free software: you can redistribute |
| 22 | * it and/or modify it under the terms of the GNU General Public License |
| 23 | * as published by the Free Software Foundation, either version 2 of the |
| 24 | * License, or (at your option) any later version. |
| 25 | * |
| 26 | * The Ubicom32 Linux Kernel Port is distributed in the hope that it |
| 27 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
| 28 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| 29 | * the GNU General Public License for more details. |
| 30 | * |
| 31 | * You should have received a copy of the GNU General Public License |
| 32 | * along with the Ubicom32 Linux Kernel Port. If not, |
| 33 | * see <http://www.gnu.org/licenses/>. |
| 34 | * |
| 35 | * Ubicom32 implementation derived from (with many thanks): |
| 36 | * arch/m68knommu |
| 37 | * arch/blackfin |
| 38 | * arch/parisc |
| 39 | */ |
| 40 | |
| 41 | #include <linux/signal.h> |
| 42 | #include <linux/sched.h> |
| 43 | #include <linux/kernel.h> |
| 44 | #include <linux/errno.h> |
| 45 | #include <linux/string.h> |
| 46 | #include <linux/types.h> |
| 47 | #include <linux/ptrace.h> |
| 48 | #include <linux/mman.h> |
| 49 | #include <linux/mm.h> |
| 50 | #include <linux/swap.h> |
| 51 | #include <linux/init.h> |
| 52 | #include <linux/highmem.h> |
| 53 | #include <linux/pagemap.h> |
| 54 | #include <linux/bootmem.h> |
| 55 | #include <linux/slab.h> |
| 56 | |
| 57 | #include <asm/setup.h> |
| 58 | #include <asm/segment.h> |
| 59 | #include <asm/page.h> |
| 60 | #include <asm/pgtable.h> |
| 61 | #include <asm/system.h> |
| 62 | #include <asm/machdep.h> |
| 63 | #include <asm/ocm-alloc.h> |
| 64 | #include <asm/processor.h> |
| 65 | |
| 66 | #undef DEBUG |
| 67 | |
| 68 | extern void die_if_kernel(char *,struct pt_regs *,long); |
| 69 | extern void free_initmem(void); |
| 70 | |
| 71 | /* |
| 72 | * BAD_PAGE is the page that is used for page faults when linux |
| 73 | * is out-of-memory. Older versions of linux just did a |
| 74 | * do_exit(), but using this instead means there is less risk |
| 75 | * for a process dying in kernel mode, possibly leaving a inode |
| 76 | * unused etc.. |
| 77 | * |
| 78 | * BAD_PAGETABLE is the accompanying page-table: it is initialized |
| 79 | * to point to BAD_PAGE entries. |
| 80 | * |
| 81 | * ZERO_PAGE is a special page that is used for zero-initialized |
| 82 | * data and COW. |
| 83 | */ |
| 84 | static unsigned long empty_bad_page_table; |
| 85 | |
| 86 | static unsigned long empty_bad_page; |
| 87 | |
| 88 | unsigned long empty_zero_page; |
| 89 | |
| 90 | void show_mem(void) |
| 91 | { |
| 92 | unsigned long i; |
| 93 | int free = 0, total = 0, reserved = 0, shared = 0; |
| 94 | int cached = 0; |
| 95 | |
| 96 | printk(KERN_INFO "\nMem-info:\n"); |
| 97 | show_free_areas(); |
| 98 | i = max_mapnr; |
| 99 | while (i-- > 0) { |
| 100 | total++; |
| 101 | if (PageReserved(mem_map+i)) |
| 102 | reserved++; |
| 103 | else if (PageSwapCache(mem_map+i)) |
| 104 | cached++; |
| 105 | else if (!page_count(mem_map+i)) |
| 106 | free++; |
| 107 | else |
| 108 | shared += page_count(mem_map+i) - 1; |
| 109 | } |
| 110 | printk(KERN_INFO "%d pages of RAM\n",total); |
| 111 | printk(KERN_INFO "%d free pages\n",free); |
| 112 | printk(KERN_INFO "%d reserved pages\n",reserved); |
| 113 | printk(KERN_INFO "%d pages shared\n",shared); |
| 114 | printk(KERN_INFO "%d pages swap cached\n",cached); |
| 115 | } |
| 116 | |
| 117 | extern unsigned long memory_start; |
| 118 | extern unsigned long memory_end; |
| 119 | extern char __ocm_free_begin; |
| 120 | extern char __ocm_free_end; |
| 121 | |
| 122 | /* |
| 123 | * paging_init() continues the virtual memory environment setup which |
| 124 | * was begun by the code in arch/head.S. |
| 125 | * The parameters are pointers to where to stick the starting and ending |
| 126 | * addresses of available kernel virtual memory. |
| 127 | */ |
| 128 | void __init paging_init(void) |
| 129 | { |
| 130 | /* |
| 131 | * Make sure start_mem is page aligned, otherwise bootmem and |
| 132 | * page_alloc get different views of the world. |
| 133 | */ |
| 134 | #ifdef DEBUG |
| 135 | unsigned long start_mem = PAGE_ALIGN(memory_start); |
| 136 | #endif |
| 137 | unsigned long end_mem = memory_end & PAGE_MASK; |
| 138 | |
| 139 | #ifdef DEBUG |
| 140 | printk (KERN_DEBUG "start_mem is %#lx\nvirtual_end is %#lx\n", |
| 141 | start_mem, end_mem); |
| 142 | #endif |
| 143 | |
| 144 | /* |
| 145 | * Initialize the bad page table and bad page to point |
| 146 | * to a couple of allocated pages. |
| 147 | */ |
| 148 | empty_bad_page_table = (unsigned long)alloc_bootmem_pages(PAGE_SIZE); |
| 149 | empty_bad_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE); |
| 150 | empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE); |
| 151 | memset((void *)empty_zero_page, 0, PAGE_SIZE); |
| 152 | |
| 153 | /* |
| 154 | * TODO: enable setting up for user memory management interface. |
| 155 | */ |
| 156 | |
| 157 | #ifdef DEBUG |
| 158 | printk (KERN_DEBUG "before free_area_init\n"); |
| 159 | |
| 160 | printk (KERN_DEBUG "free_area_init -> start_mem is %#lx\nvirtual_end is %#lx\n", |
| 161 | start_mem, end_mem); |
| 162 | #endif |
| 163 | |
| 164 | { |
| 165 | unsigned long zones_size[MAX_NR_ZONES] = {0, }; |
| 166 | #ifdef CONFIG_ZONE_DMA |
| 167 | zones_size[ZONE_DMA] = OCMSIZE >> PAGE_SHIFT; |
| 168 | #endif |
| 169 | zones_size[ZONE_NORMAL] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT; |
| 170 | #ifdef CONFIG_HIGHMEM |
| 171 | zones_size[ZONE_HIGHMEM] = 0; |
| 172 | #endif |
| 173 | free_area_init(zones_size); |
| 174 | } |
| 175 | } |
| 176 | |
| 177 | void __init mem_init(void) |
| 178 | { |
| 179 | int codek = 0, datak = 0, initk = 0; |
| 180 | unsigned long tmp, ram_start, ram_end, len; |
| 181 | extern char _etext, _stext, _sdata, _ebss, __init_begin, __init_end; |
| 182 | |
| 183 | unsigned long start_mem = memory_start; /* DAVIDM - these must start at end of kernel */ |
| 184 | unsigned long end_mem = memory_end; /* DAVIDM - this must not include kernel stack at top */ |
| 185 | processor_dram(&ram_start, &ram_end); |
| 186 | len = (ram_end - ram_start) + OCMSIZE; |
| 187 | #ifdef DEBUG |
| 188 | printk(KERN_DEBUG "Mem_init: start=%lx, end=%lx\n", start_mem, end_mem); |
| 189 | #endif |
| 190 | |
| 191 | end_mem &= PAGE_MASK; |
| 192 | high_memory = (void *) end_mem; |
| 193 | |
| 194 | start_mem = PAGE_ALIGN(start_mem); |
| 195 | max_mapnr = num_physpages = (((unsigned long) high_memory) - PAGE_OFFSET) >> PAGE_SHIFT; |
| 196 | |
| 197 | /* this will put all memory onto the freelists */ |
| 198 | #ifdef CONFIG_ZONE_DMA |
| 199 | { |
| 200 | unsigned long ocm_free_begin = (unsigned long)&__ocm_free_begin; |
| 201 | unsigned long ocm_free_end = (unsigned long)&__ocm_free_end; |
| 202 | unsigned long zone_dma_begin = (ocm_free_begin + PAGE_SIZE - 1) & PAGE_MASK; |
| 203 | unsigned long zone_dma_end = ocm_free_end & PAGE_MASK; |
| 204 | if (zone_dma_end > zone_dma_begin) |
| 205 | free_bootmem(zone_dma_begin, zone_dma_end-zone_dma_begin); |
| 206 | } |
| 207 | #endif |
| 208 | totalram_pages = free_all_bootmem(); |
| 209 | |
| 210 | codek = (&_etext - &_stext) >> 10; |
| 211 | datak = (&_ebss - &_sdata) >> 10; |
| 212 | initk = (&__init_begin - &__init_end) >> 10; |
| 213 | |
| 214 | tmp = nr_free_pages() << PAGE_SHIFT; |
| 215 | printk(KERN_INFO "Memory available: %luk/%luk RAM, (%dk kernel code, %dk data)\n", |
| 216 | tmp >> 10, |
| 217 | len >> 10, |
| 218 | codek, |
| 219 | datak |
| 220 | ); |
| 221 | |
| 222 | } |
| 223 | |
| 224 | #ifdef CONFIG_BLK_DEV_INITRD |
| 225 | void free_initrd_mem(unsigned long start, unsigned long end) |
| 226 | { |
| 227 | int pages = 0; |
| 228 | for (; start < end; start += PAGE_SIZE) { |
| 229 | ClearPageReserved(virt_to_page(start)); |
| 230 | init_page_count(virt_to_page(start)); |
| 231 | free_page(start); |
| 232 | totalram_pages++; |
| 233 | pages++; |
| 234 | } |
| 235 | printk (KERN_NOTICE "Freeing initrd memory: %dk freed\n", pages); |
| 236 | } |
| 237 | #endif |
| 238 | |
| 239 | void |
| 240 | free_initmem() |
| 241 | { |
| 242 | #ifdef CONFIG_RAMKERNEL |
| 243 | unsigned long addr; |
| 244 | extern char __init_begin, __init_end; |
| 245 | /* |
| 246 | * The following code should be cool even if these sections |
| 247 | * are not page aligned. |
| 248 | */ |
| 249 | addr = PAGE_ALIGN((unsigned long)(&__init_begin)); |
| 250 | /* next to check that the page we free is not a partial page */ |
| 251 | for (; addr + PAGE_SIZE < (unsigned long)(&__init_end); addr +=PAGE_SIZE) { |
| 252 | ClearPageReserved(virt_to_page(addr)); |
| 253 | init_page_count(virt_to_page(addr)); |
| 254 | free_page(addr); |
| 255 | totalram_pages++; |
| 256 | } |
| 257 | printk(KERN_NOTICE "Freeing unused kernel memory: %ldk freed (0x%x - 0x%x)\n", |
| 258 | (addr - PAGE_ALIGN((long) &__init_begin)) >> 10, |
| 259 | (int)(PAGE_ALIGN((unsigned long)(&__init_begin))), |
| 260 | (int)(addr - PAGE_SIZE)); |
| 261 | #endif |
| 262 | } |
| 263 | |
