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 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 21 | #include <linux/module.h> |
| 22 | #include <linux/sched.h> |
| 23 | #include <linux/kernel.h> |
| 24 | #include <linux/errno.h> |
| 25 | #include <linux/string.h> |
| 26 | #include <linux/types.h> |
| 27 | #include <linux/mm.h> |
| 28 | #include <linux/stddef.h> |
| 29 | #include <linux/init.h> |
| 30 | #include <linux/bootmem.h> |
| 31 | #include <linux/highmem.h> |
| 32 | #include <linux/initrd.h> |
| 33 | #include <linux/pagemap.h> |
| 34 | |
| 35 | #include <asm/pgalloc.h> |
| 36 | #include <asm/prom.h> |
| 37 | #include <asm/io.h> |
| 38 | #include <asm/mmu_context.h> |
| 39 | #include <asm/pgtable.h> |
| 40 | #include <asm/mmu.h> |
| 41 | #include <asm/smp.h> |
| 42 | #include <asm/machdep.h> |
| 43 | #include <asm/btext.h> |
| 44 | #include <asm/tlb.h> |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 45 | #include <asm/prom.h> |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 46 | #include <asm/lmb.h> |
| 47 | #include <asm/sections.h> |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 48 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 49 | #include "mmu_decl.h" |
| 50 | |
| 51 | #if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL) |
| 52 | /* The ammount of lowmem must be within 0xF0000000 - KERNELBASE. */ |
| 53 | #if (CONFIG_LOWMEM_SIZE > (0xF0000000 - KERNELBASE)) |
| 54 | #error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL" |
| 55 | #endif |
| 56 | #endif |
| 57 | #define MAX_LOW_MEM CONFIG_LOWMEM_SIZE |
| 58 | |
| 59 | DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); |
| 60 | |
| 61 | unsigned long total_memory; |
| 62 | unsigned long total_lowmem; |
| 63 | |
| 64 | unsigned long ppc_memstart; |
| 65 | unsigned long ppc_memoffset = PAGE_OFFSET; |
| 66 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 67 | int boot_mapsize; |
| 68 | #ifdef CONFIG_PPC_PMAC |
| 69 | unsigned long agp_special_page; |
Paul Mackerras | 5c8c56e | 2005-10-22 14:42:51 +1000 | [diff] [blame] | 70 | EXPORT_SYMBOL(agp_special_page); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 71 | #endif |
| 72 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 73 | #ifdef CONFIG_HIGHMEM |
| 74 | pte_t *kmap_pte; |
| 75 | pgprot_t kmap_prot; |
| 76 | |
| 77 | EXPORT_SYMBOL(kmap_prot); |
| 78 | EXPORT_SYMBOL(kmap_pte); |
| 79 | #endif |
| 80 | |
| 81 | void MMU_init(void); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 82 | |
| 83 | /* XXX should be in current.h -- paulus */ |
| 84 | extern struct task_struct *current_set[NR_CPUS]; |
| 85 | |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 86 | extern int init_bootmem_done; |
| 87 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 88 | /* |
| 89 | * this tells the system to map all of ram with the segregs |
| 90 | * (i.e. page tables) instead of the bats. |
| 91 | * -- Cort |
| 92 | */ |
| 93 | int __map_without_bats; |
| 94 | int __map_without_ltlbs; |
| 95 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 96 | /* max amount of low RAM to map in */ |
| 97 | unsigned long __max_low_memory = MAX_LOW_MEM; |
| 98 | |
| 99 | /* |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 100 | * limit of what is accessible with initial MMU setup - |
| 101 | * 256MB usually, but only 16MB on 601. |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 102 | */ |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 103 | unsigned long __initial_memory_limit = 0x10000000; |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 104 | |
| 105 | /* |
| 106 | * Check for command-line options that affect what MMU_init will do. |
| 107 | */ |
| 108 | void MMU_setup(void) |
| 109 | { |
| 110 | /* Check for nobats option (used in mapin_ram). */ |
| 111 | if (strstr(cmd_line, "nobats")) { |
| 112 | __map_without_bats = 1; |
| 113 | } |
| 114 | |
| 115 | if (strstr(cmd_line, "noltlbs")) { |
| 116 | __map_without_ltlbs = 1; |
| 117 | } |
Benjamin Herrenschmidt | 88df6e9 | 2007-04-12 15:30:22 +1000 | [diff] [blame] | 118 | #ifdef CONFIG_DEBUG_PAGEALLOC |
| 119 | __map_without_bats = 1; |
| 120 | __map_without_ltlbs = 1; |
| 121 | #endif |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 122 | } |
| 123 | |
| 124 | /* |
| 125 | * MMU_init sets up the basic memory mappings for the kernel, |
| 126 | * including both RAM and possibly some I/O regions, |
| 127 | * and sets up the page tables and the MMU hardware ready to go. |
| 128 | */ |
| 129 | void __init MMU_init(void) |
| 130 | { |
| 131 | if (ppc_md.progress) |
| 132 | ppc_md.progress("MMU:enter", 0x111); |
| 133 | |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 134 | /* 601 can only access 16MB at the moment */ |
| 135 | if (PVR_VER(mfspr(SPRN_PVR)) == 1) |
| 136 | __initial_memory_limit = 0x01000000; |
| 137 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 138 | /* parse args from command line */ |
| 139 | MMU_setup(); |
| 140 | |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 141 | if (lmb.memory.cnt > 1) { |
| 142 | lmb.memory.cnt = 1; |
| 143 | lmb_analyze(); |
| 144 | printk(KERN_WARNING "Only using first contiguous memory region"); |
| 145 | } |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 146 | |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 147 | total_memory = lmb_end_of_DRAM(); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 148 | total_lowmem = total_memory; |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 149 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 150 | #ifdef CONFIG_FSL_BOOKE |
| 151 | /* Freescale Book-E parts expect lowmem to be mapped by fixed TLB |
| 152 | * entries, so we need to adjust lowmem to match the amount we can map |
| 153 | * in the fixed entries */ |
| 154 | adjust_total_lowmem(); |
| 155 | #endif /* CONFIG_FSL_BOOKE */ |
Paul Mackerras | fa39dc4 | 2005-10-26 21:54:21 +1000 | [diff] [blame] | 156 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 157 | if (total_lowmem > __max_low_memory) { |
| 158 | total_lowmem = __max_low_memory; |
| 159 | #ifndef CONFIG_HIGHMEM |
| 160 | total_memory = total_lowmem; |
Paul Mackerras | fa39dc4 | 2005-10-26 21:54:21 +1000 | [diff] [blame] | 161 | lmb_enforce_memory_limit(total_lowmem); |
| 162 | lmb_analyze(); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 163 | #endif /* CONFIG_HIGHMEM */ |
| 164 | } |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 165 | |
| 166 | /* Initialize the MMU hardware */ |
| 167 | if (ppc_md.progress) |
| 168 | ppc_md.progress("MMU:hw init", 0x300); |
| 169 | MMU_init_hw(); |
| 170 | |
| 171 | /* Map in all of RAM starting at KERNELBASE */ |
| 172 | if (ppc_md.progress) |
| 173 | ppc_md.progress("MMU:mapin", 0x301); |
| 174 | mapin_ram(); |
| 175 | |
| 176 | #ifdef CONFIG_HIGHMEM |
| 177 | ioremap_base = PKMAP_BASE; |
| 178 | #else |
| 179 | ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */ |
| 180 | #endif /* CONFIG_HIGHMEM */ |
| 181 | ioremap_bot = ioremap_base; |
| 182 | |
| 183 | /* Map in I/O resources */ |
| 184 | if (ppc_md.progress) |
| 185 | ppc_md.progress("MMU:setio", 0x302); |
| 186 | if (ppc_md.setup_io_mappings) |
| 187 | ppc_md.setup_io_mappings(); |
| 188 | |
| 189 | /* Initialize the context management stuff */ |
| 190 | mmu_context_init(); |
| 191 | |
| 192 | if (ppc_md.progress) |
| 193 | ppc_md.progress("MMU:exit", 0x211); |
Benjamin Herrenschmidt | 51d3082 | 2005-11-23 17:57:25 +1100 | [diff] [blame] | 194 | |
| 195 | /* From now on, btext is no longer BAT mapped if it was at all */ |
| 196 | #ifdef CONFIG_BOOTX_TEXT |
| 197 | btext_unmap(); |
| 198 | #endif |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 199 | } |
| 200 | |
| 201 | /* This is only called until mem_init is done. */ |
| 202 | void __init *early_get_page(void) |
| 203 | { |
| 204 | void *p; |
| 205 | |
| 206 | if (init_bootmem_done) { |
| 207 | p = alloc_bootmem_pages(PAGE_SIZE); |
| 208 | } else { |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 209 | p = __va(lmb_alloc_base(PAGE_SIZE, PAGE_SIZE, |
| 210 | __initial_memory_limit)); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 211 | } |
| 212 | return p; |
| 213 | } |
| 214 | |
| 215 | /* Free up now-unused memory */ |
| 216 | static void free_sec(unsigned long start, unsigned long end, const char *name) |
| 217 | { |
| 218 | unsigned long cnt = 0; |
| 219 | |
| 220 | while (start < end) { |
| 221 | ClearPageReserved(virt_to_page(start)); |
Nick Piggin | 7835e98 | 2006-03-22 00:08:40 -0800 | [diff] [blame] | 222 | init_page_count(virt_to_page(start)); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 223 | free_page(start); |
| 224 | cnt++; |
| 225 | start += PAGE_SIZE; |
| 226 | } |
| 227 | if (cnt) { |
| 228 | printk(" %ldk %s", cnt << (PAGE_SHIFT - 10), name); |
| 229 | totalram_pages += cnt; |
| 230 | } |
| 231 | } |
| 232 | |
| 233 | void free_initmem(void) |
| 234 | { |
| 235 | #define FREESEC(TYPE) \ |
| 236 | free_sec((unsigned long)(&__ ## TYPE ## _begin), \ |
| 237 | (unsigned long)(&__ ## TYPE ## _end), \ |
| 238 | #TYPE); |
| 239 | |
| 240 | printk ("Freeing unused kernel memory:"); |
| 241 | FREESEC(init); |
| 242 | printk("\n"); |
| 243 | ppc_md.progress = NULL; |
| 244 | #undef FREESEC |
| 245 | } |
| 246 | |
| 247 | #ifdef CONFIG_BLK_DEV_INITRD |
| 248 | void free_initrd_mem(unsigned long start, unsigned long end) |
| 249 | { |
| 250 | if (start < end) |
| 251 | printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); |
| 252 | for (; start < end; start += PAGE_SIZE) { |
| 253 | ClearPageReserved(virt_to_page(start)); |
Nick Piggin | 7835e98 | 2006-03-22 00:08:40 -0800 | [diff] [blame] | 254 | init_page_count(virt_to_page(start)); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 255 | free_page(start); |
| 256 | totalram_pages++; |
| 257 | } |
| 258 | } |
| 259 | #endif |