Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 1 | /* |
| 2 | * PowerPC version |
| 3 | * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) |
| 4 | * |
| 5 | * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) |
| 6 | * and Cort Dougan (PReP) (cort@cs.nmt.edu) |
| 7 | * Copyright (C) 1996 Paul Mackerras |
| 8 | * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk). |
| 9 | * PPC44x/36-bit changes by Matt Porter (mporter@mvista.com) |
| 10 | * |
| 11 | * Derived from "arch/i386/mm/init.c" |
| 12 | * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds |
| 13 | * |
| 14 | * This program is free software; you can redistribute it and/or |
| 15 | * modify it under the terms of the GNU General Public License |
| 16 | * as published by the Free Software Foundation; either version |
| 17 | * 2 of the License, or (at your option) any later version. |
| 18 | * |
| 19 | */ |
| 20 | |
| 21 | #include <linux/config.h> |
| 22 | #include <linux/module.h> |
| 23 | #include <linux/sched.h> |
| 24 | #include <linux/kernel.h> |
| 25 | #include <linux/errno.h> |
| 26 | #include <linux/string.h> |
| 27 | #include <linux/types.h> |
| 28 | #include <linux/mm.h> |
| 29 | #include <linux/stddef.h> |
| 30 | #include <linux/init.h> |
| 31 | #include <linux/bootmem.h> |
| 32 | #include <linux/highmem.h> |
| 33 | #include <linux/initrd.h> |
| 34 | #include <linux/pagemap.h> |
| 35 | |
| 36 | #include <asm/pgalloc.h> |
| 37 | #include <asm/prom.h> |
| 38 | #include <asm/io.h> |
| 39 | #include <asm/mmu_context.h> |
| 40 | #include <asm/pgtable.h> |
| 41 | #include <asm/mmu.h> |
| 42 | #include <asm/smp.h> |
| 43 | #include <asm/machdep.h> |
| 44 | #include <asm/btext.h> |
| 45 | #include <asm/tlb.h> |
| 46 | #include <asm/bootinfo.h> |
| 47 | #include <asm/prom.h> |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 48 | #include <asm/lmb.h> |
| 49 | #include <asm/sections.h> |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 50 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 51 | #include "mmu_decl.h" |
| 52 | |
| 53 | #if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL) |
| 54 | /* The ammount of lowmem must be within 0xF0000000 - KERNELBASE. */ |
| 55 | #if (CONFIG_LOWMEM_SIZE > (0xF0000000 - KERNELBASE)) |
| 56 | #error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL" |
| 57 | #endif |
| 58 | #endif |
| 59 | #define MAX_LOW_MEM CONFIG_LOWMEM_SIZE |
| 60 | |
| 61 | DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); |
| 62 | |
| 63 | unsigned long total_memory; |
| 64 | unsigned long total_lowmem; |
| 65 | |
| 66 | unsigned long ppc_memstart; |
| 67 | unsigned long ppc_memoffset = PAGE_OFFSET; |
| 68 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 69 | int boot_mapsize; |
| 70 | #ifdef CONFIG_PPC_PMAC |
| 71 | unsigned long agp_special_page; |
Paul Mackerras | 5c8c56e | 2005-10-22 14:42:51 +1000 | [diff] [blame^] | 72 | EXPORT_SYMBOL(agp_special_page); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 73 | #endif |
| 74 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 75 | #ifdef CONFIG_HIGHMEM |
| 76 | pte_t *kmap_pte; |
| 77 | pgprot_t kmap_prot; |
| 78 | |
| 79 | EXPORT_SYMBOL(kmap_prot); |
| 80 | EXPORT_SYMBOL(kmap_pte); |
| 81 | #endif |
| 82 | |
| 83 | void MMU_init(void); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 84 | |
| 85 | /* XXX should be in current.h -- paulus */ |
| 86 | extern struct task_struct *current_set[NR_CPUS]; |
| 87 | |
| 88 | char *klimit = _end; |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 89 | struct device_node *memory_node; |
| 90 | |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 91 | extern int init_bootmem_done; |
| 92 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 93 | /* |
| 94 | * this tells the system to map all of ram with the segregs |
| 95 | * (i.e. page tables) instead of the bats. |
| 96 | * -- Cort |
| 97 | */ |
| 98 | int __map_without_bats; |
| 99 | int __map_without_ltlbs; |
| 100 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 101 | /* max amount of low RAM to map in */ |
| 102 | unsigned long __max_low_memory = MAX_LOW_MEM; |
| 103 | |
| 104 | /* |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 105 | * limit of what is accessible with initial MMU setup - |
| 106 | * 256MB usually, but only 16MB on 601. |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 107 | */ |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 108 | unsigned long __initial_memory_limit = 0x10000000; |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 109 | |
| 110 | /* |
| 111 | * Check for command-line options that affect what MMU_init will do. |
| 112 | */ |
| 113 | void MMU_setup(void) |
| 114 | { |
| 115 | /* Check for nobats option (used in mapin_ram). */ |
| 116 | if (strstr(cmd_line, "nobats")) { |
| 117 | __map_without_bats = 1; |
| 118 | } |
| 119 | |
| 120 | if (strstr(cmd_line, "noltlbs")) { |
| 121 | __map_without_ltlbs = 1; |
| 122 | } |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 123 | } |
| 124 | |
| 125 | /* |
| 126 | * MMU_init sets up the basic memory mappings for the kernel, |
| 127 | * including both RAM and possibly some I/O regions, |
| 128 | * and sets up the page tables and the MMU hardware ready to go. |
| 129 | */ |
| 130 | void __init MMU_init(void) |
| 131 | { |
| 132 | if (ppc_md.progress) |
| 133 | ppc_md.progress("MMU:enter", 0x111); |
| 134 | |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 135 | /* 601 can only access 16MB at the moment */ |
| 136 | if (PVR_VER(mfspr(SPRN_PVR)) == 1) |
| 137 | __initial_memory_limit = 0x01000000; |
| 138 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 139 | /* parse args from command line */ |
| 140 | MMU_setup(); |
| 141 | |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 142 | if (lmb.memory.cnt > 1) { |
| 143 | lmb.memory.cnt = 1; |
| 144 | lmb_analyze(); |
| 145 | printk(KERN_WARNING "Only using first contiguous memory region"); |
| 146 | } |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 147 | |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 148 | total_memory = lmb_end_of_DRAM(); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 149 | total_lowmem = total_memory; |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 150 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 151 | #ifdef CONFIG_FSL_BOOKE |
| 152 | /* Freescale Book-E parts expect lowmem to be mapped by fixed TLB |
| 153 | * entries, so we need to adjust lowmem to match the amount we can map |
| 154 | * in the fixed entries */ |
| 155 | adjust_total_lowmem(); |
| 156 | #endif /* CONFIG_FSL_BOOKE */ |
| 157 | if (total_lowmem > __max_low_memory) { |
| 158 | total_lowmem = __max_low_memory; |
| 159 | #ifndef CONFIG_HIGHMEM |
| 160 | total_memory = total_lowmem; |
| 161 | #endif /* CONFIG_HIGHMEM */ |
| 162 | } |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 163 | |
| 164 | /* Initialize the MMU hardware */ |
| 165 | if (ppc_md.progress) |
| 166 | ppc_md.progress("MMU:hw init", 0x300); |
| 167 | MMU_init_hw(); |
| 168 | |
| 169 | /* Map in all of RAM starting at KERNELBASE */ |
| 170 | if (ppc_md.progress) |
| 171 | ppc_md.progress("MMU:mapin", 0x301); |
| 172 | mapin_ram(); |
| 173 | |
| 174 | #ifdef CONFIG_HIGHMEM |
| 175 | ioremap_base = PKMAP_BASE; |
| 176 | #else |
| 177 | ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */ |
| 178 | #endif /* CONFIG_HIGHMEM */ |
| 179 | ioremap_bot = ioremap_base; |
| 180 | |
| 181 | /* Map in I/O resources */ |
| 182 | if (ppc_md.progress) |
| 183 | ppc_md.progress("MMU:setio", 0x302); |
| 184 | if (ppc_md.setup_io_mappings) |
| 185 | ppc_md.setup_io_mappings(); |
| 186 | |
| 187 | /* Initialize the context management stuff */ |
| 188 | mmu_context_init(); |
| 189 | |
| 190 | if (ppc_md.progress) |
| 191 | ppc_md.progress("MMU:exit", 0x211); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 192 | } |
| 193 | |
| 194 | /* This is only called until mem_init is done. */ |
| 195 | void __init *early_get_page(void) |
| 196 | { |
| 197 | void *p; |
| 198 | |
| 199 | if (init_bootmem_done) { |
| 200 | p = alloc_bootmem_pages(PAGE_SIZE); |
| 201 | } else { |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 202 | p = __va(lmb_alloc_base(PAGE_SIZE, PAGE_SIZE, |
| 203 | __initial_memory_limit)); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 204 | } |
| 205 | return p; |
| 206 | } |
| 207 | |
| 208 | /* Free up now-unused memory */ |
| 209 | static void free_sec(unsigned long start, unsigned long end, const char *name) |
| 210 | { |
| 211 | unsigned long cnt = 0; |
| 212 | |
| 213 | while (start < end) { |
| 214 | ClearPageReserved(virt_to_page(start)); |
| 215 | set_page_count(virt_to_page(start), 1); |
| 216 | free_page(start); |
| 217 | cnt++; |
| 218 | start += PAGE_SIZE; |
| 219 | } |
| 220 | if (cnt) { |
| 221 | printk(" %ldk %s", cnt << (PAGE_SHIFT - 10), name); |
| 222 | totalram_pages += cnt; |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | void free_initmem(void) |
| 227 | { |
| 228 | #define FREESEC(TYPE) \ |
| 229 | free_sec((unsigned long)(&__ ## TYPE ## _begin), \ |
| 230 | (unsigned long)(&__ ## TYPE ## _end), \ |
| 231 | #TYPE); |
| 232 | |
| 233 | printk ("Freeing unused kernel memory:"); |
| 234 | FREESEC(init); |
| 235 | printk("\n"); |
| 236 | ppc_md.progress = NULL; |
| 237 | #undef FREESEC |
| 238 | } |
| 239 | |
| 240 | #ifdef CONFIG_BLK_DEV_INITRD |
| 241 | void free_initrd_mem(unsigned long start, unsigned long end) |
| 242 | { |
| 243 | if (start < end) |
| 244 | printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); |
| 245 | for (; start < end; start += PAGE_SIZE) { |
| 246 | ClearPageReserved(virt_to_page(start)); |
| 247 | set_page_count(virt_to_page(start), 1); |
| 248 | free_page(start); |
| 249 | totalram_pages++; |
| 250 | } |
| 251 | } |
| 252 | #endif |