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 |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 8 | * PPC44x/36-bit changes by Matt Porter (mporter@mvista.com) |
| 9 | * |
| 10 | * Derived from "arch/i386/mm/init.c" |
| 11 | * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds |
| 12 | * |
| 13 | * This program is free software; you can redistribute it and/or |
| 14 | * modify it under the terms of the GNU General Public License |
| 15 | * as published by the Free Software Foundation; either version |
| 16 | * 2 of the License, or (at your option) any later version. |
| 17 | * |
| 18 | */ |
| 19 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 20 | #include <linux/module.h> |
| 21 | #include <linux/sched.h> |
| 22 | #include <linux/kernel.h> |
| 23 | #include <linux/errno.h> |
| 24 | #include <linux/string.h> |
| 25 | #include <linux/types.h> |
| 26 | #include <linux/mm.h> |
| 27 | #include <linux/stddef.h> |
| 28 | #include <linux/init.h> |
| 29 | #include <linux/bootmem.h> |
| 30 | #include <linux/highmem.h> |
| 31 | #include <linux/initrd.h> |
| 32 | #include <linux/pagemap.h> |
David S. Miller | d9b2b2a | 2008-02-13 16:56:49 -0800 | [diff] [blame] | 33 | #include <linux/lmb.h> |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 34 | |
| 35 | #include <asm/pgalloc.h> |
| 36 | #include <asm/prom.h> |
| 37 | #include <asm/io.h> |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 38 | #include <asm/pgtable.h> |
| 39 | #include <asm/mmu.h> |
| 40 | #include <asm/smp.h> |
| 41 | #include <asm/machdep.h> |
| 42 | #include <asm/btext.h> |
| 43 | #include <asm/tlb.h> |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 44 | #include <asm/sections.h> |
Michael Ellerman | 5f25f065 | 2008-05-08 14:27:07 +1000 | [diff] [blame] | 45 | #include <asm/system.h> |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 46 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 47 | #include "mmu_decl.h" |
| 48 | |
| 49 | #if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL) |
| 50 | /* The ammount of lowmem must be within 0xF0000000 - KERNELBASE. */ |
Dale Farnsworth | ccdcef7 | 2008-12-17 10:09:13 +0000 | [diff] [blame] | 51 | #if (CONFIG_LOWMEM_SIZE > (0xF0000000 - PAGE_OFFSET)) |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 52 | #error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL" |
| 53 | #endif |
| 54 | #endif |
| 55 | #define MAX_LOW_MEM CONFIG_LOWMEM_SIZE |
| 56 | |
Stefan Roese | 2bf3016 | 2008-07-10 01:09:23 +1000 | [diff] [blame] | 57 | phys_addr_t total_memory; |
| 58 | phys_addr_t total_lowmem; |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 59 | |
Kumar Gala | 37dd2ba | 2008-04-22 04:22:34 +1000 | [diff] [blame] | 60 | phys_addr_t memstart_addr = (phys_addr_t)~0ull; |
| 61 | EXPORT_SYMBOL(memstart_addr); |
| 62 | phys_addr_t kernstart_addr; |
| 63 | EXPORT_SYMBOL(kernstart_addr); |
Kumar Gala | 99c62dd7 | 2008-04-16 05:52:21 +1000 | [diff] [blame] | 64 | phys_addr_t lowmem_end_addr; |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 65 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 66 | int boot_mapsize; |
| 67 | #ifdef CONFIG_PPC_PMAC |
| 68 | unsigned long agp_special_page; |
Paul Mackerras | 5c8c56e | 2005-10-22 14:42:51 +1000 | [diff] [blame] | 69 | EXPORT_SYMBOL(agp_special_page); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 70 | #endif |
| 71 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 72 | void MMU_init(void); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 73 | |
| 74 | /* XXX should be in current.h -- paulus */ |
| 75 | extern struct task_struct *current_set[NR_CPUS]; |
| 76 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 77 | /* |
| 78 | * this tells the system to map all of ram with the segregs |
| 79 | * (i.e. page tables) instead of the bats. |
| 80 | * -- Cort |
| 81 | */ |
| 82 | int __map_without_bats; |
| 83 | int __map_without_ltlbs; |
| 84 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 85 | /* max amount of low RAM to map in */ |
| 86 | unsigned long __max_low_memory = MAX_LOW_MEM; |
| 87 | |
| 88 | /* |
Kumar Gala | 09b5e63 | 2008-04-16 05:52:25 +1000 | [diff] [blame] | 89 | * address of the limit of what is accessible with initial MMU setup - |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 90 | * 256MB usually, but only 16MB on 601. |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 91 | */ |
Kumar Gala | 09b5e63 | 2008-04-16 05:52:25 +1000 | [diff] [blame] | 92 | phys_addr_t __initial_memory_limit_addr = (phys_addr_t)0x10000000; |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 93 | |
| 94 | /* |
| 95 | * Check for command-line options that affect what MMU_init will do. |
| 96 | */ |
| 97 | void MMU_setup(void) |
| 98 | { |
| 99 | /* Check for nobats option (used in mapin_ram). */ |
| 100 | if (strstr(cmd_line, "nobats")) { |
| 101 | __map_without_bats = 1; |
| 102 | } |
| 103 | |
| 104 | if (strstr(cmd_line, "noltlbs")) { |
| 105 | __map_without_ltlbs = 1; |
| 106 | } |
Benjamin Herrenschmidt | 88df6e9 | 2007-04-12 15:30:22 +1000 | [diff] [blame] | 107 | #ifdef CONFIG_DEBUG_PAGEALLOC |
| 108 | __map_without_bats = 1; |
| 109 | __map_without_ltlbs = 1; |
| 110 | #endif |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 111 | } |
| 112 | |
| 113 | /* |
| 114 | * MMU_init sets up the basic memory mappings for the kernel, |
| 115 | * including both RAM and possibly some I/O regions, |
| 116 | * and sets up the page tables and the MMU hardware ready to go. |
| 117 | */ |
| 118 | void __init MMU_init(void) |
| 119 | { |
| 120 | if (ppc_md.progress) |
| 121 | ppc_md.progress("MMU:enter", 0x111); |
| 122 | |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 123 | /* 601 can only access 16MB at the moment */ |
| 124 | if (PVR_VER(mfspr(SPRN_PVR)) == 1) |
Kumar Gala | 09b5e63 | 2008-04-16 05:52:25 +1000 | [diff] [blame] | 125 | __initial_memory_limit_addr = 0x01000000; |
John Traill | 544cdab | 2007-07-17 05:17:23 +0400 | [diff] [blame] | 126 | /* 8xx can only access 8MB at the moment */ |
| 127 | if (PVR_VER(mfspr(SPRN_PVR)) == 0x50) |
Kumar Gala | 09b5e63 | 2008-04-16 05:52:25 +1000 | [diff] [blame] | 128 | __initial_memory_limit_addr = 0x00800000; |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 129 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 130 | /* parse args from command line */ |
| 131 | MMU_setup(); |
| 132 | |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 133 | if (lmb.memory.cnt > 1) { |
| 134 | lmb.memory.cnt = 1; |
| 135 | lmb_analyze(); |
| 136 | printk(KERN_WARNING "Only using first contiguous memory region"); |
| 137 | } |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 138 | |
Kumar Gala | 99c62dd7 | 2008-04-16 05:52:21 +1000 | [diff] [blame] | 139 | total_lowmem = total_memory = lmb_end_of_DRAM() - memstart_addr; |
Kumar Gala | d7917ba | 2008-04-16 05:52:22 +1000 | [diff] [blame] | 140 | lowmem_end_addr = memstart_addr + total_lowmem; |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 141 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 142 | #ifdef CONFIG_FSL_BOOKE |
| 143 | /* Freescale Book-E parts expect lowmem to be mapped by fixed TLB |
| 144 | * entries, so we need to adjust lowmem to match the amount we can map |
| 145 | * in the fixed entries */ |
| 146 | adjust_total_lowmem(); |
| 147 | #endif /* CONFIG_FSL_BOOKE */ |
Paul Mackerras | fa39dc4 | 2005-10-26 21:54:21 +1000 | [diff] [blame] | 148 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 149 | if (total_lowmem > __max_low_memory) { |
| 150 | total_lowmem = __max_low_memory; |
Kumar Gala | d7917ba | 2008-04-16 05:52:22 +1000 | [diff] [blame] | 151 | lowmem_end_addr = memstart_addr + total_lowmem; |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 152 | #ifndef CONFIG_HIGHMEM |
| 153 | total_memory = total_lowmem; |
Kumar Gala | d7917ba | 2008-04-16 05:52:22 +1000 | [diff] [blame] | 154 | lmb_enforce_memory_limit(lowmem_end_addr); |
Paul Mackerras | fa39dc4 | 2005-10-26 21:54:21 +1000 | [diff] [blame] | 155 | lmb_analyze(); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 156 | #endif /* CONFIG_HIGHMEM */ |
| 157 | } |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 158 | |
| 159 | /* Initialize the MMU hardware */ |
| 160 | if (ppc_md.progress) |
| 161 | ppc_md.progress("MMU:hw init", 0x300); |
| 162 | MMU_init_hw(); |
| 163 | |
| 164 | /* Map in all of RAM starting at KERNELBASE */ |
| 165 | if (ppc_md.progress) |
| 166 | ppc_md.progress("MMU:mapin", 0x301); |
| 167 | mapin_ram(); |
| 168 | |
Benjamin Herrenschmidt | f637a49 | 2009-05-27 13:44:50 +1000 | [diff] [blame] | 169 | /* Initialize early top-down ioremap allocator */ |
| 170 | ioremap_bot = IOREMAP_TOP; |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 171 | |
| 172 | /* Map in I/O resources */ |
| 173 | if (ppc_md.progress) |
| 174 | ppc_md.progress("MMU:setio", 0x302); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 175 | |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 176 | if (ppc_md.progress) |
| 177 | ppc_md.progress("MMU:exit", 0x211); |
Benjamin Herrenschmidt | 51d3082 | 2005-11-23 17:57:25 +1100 | [diff] [blame] | 178 | |
| 179 | /* From now on, btext is no longer BAT mapped if it was at all */ |
| 180 | #ifdef CONFIG_BOOTX_TEXT |
| 181 | btext_unmap(); |
| 182 | #endif |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 183 | } |
| 184 | |
| 185 | /* This is only called until mem_init is done. */ |
| 186 | void __init *early_get_page(void) |
| 187 | { |
| 188 | void *p; |
| 189 | |
| 190 | if (init_bootmem_done) { |
| 191 | p = alloc_bootmem_pages(PAGE_SIZE); |
| 192 | } else { |
Paul Mackerras | 7c8c6b9 | 2005-10-06 12:23:33 +1000 | [diff] [blame] | 193 | p = __va(lmb_alloc_base(PAGE_SIZE, PAGE_SIZE, |
Kumar Gala | 09b5e63 | 2008-04-16 05:52:25 +1000 | [diff] [blame] | 194 | __initial_memory_limit_addr)); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 195 | } |
| 196 | return p; |
| 197 | } |
| 198 | |
| 199 | /* Free up now-unused memory */ |
| 200 | static void free_sec(unsigned long start, unsigned long end, const char *name) |
| 201 | { |
| 202 | unsigned long cnt = 0; |
| 203 | |
| 204 | while (start < end) { |
| 205 | ClearPageReserved(virt_to_page(start)); |
Nick Piggin | 7835e98 | 2006-03-22 00:08:40 -0800 | [diff] [blame] | 206 | init_page_count(virt_to_page(start)); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 207 | free_page(start); |
| 208 | cnt++; |
| 209 | start += PAGE_SIZE; |
| 210 | } |
| 211 | if (cnt) { |
| 212 | printk(" %ldk %s", cnt << (PAGE_SHIFT - 10), name); |
| 213 | totalram_pages += cnt; |
| 214 | } |
| 215 | } |
| 216 | |
| 217 | void free_initmem(void) |
| 218 | { |
| 219 | #define FREESEC(TYPE) \ |
| 220 | free_sec((unsigned long)(&__ ## TYPE ## _begin), \ |
| 221 | (unsigned long)(&__ ## TYPE ## _end), \ |
| 222 | #TYPE); |
| 223 | |
| 224 | printk ("Freeing unused kernel memory:"); |
| 225 | FREESEC(init); |
| 226 | printk("\n"); |
| 227 | ppc_md.progress = NULL; |
| 228 | #undef FREESEC |
| 229 | } |
| 230 | |
| 231 | #ifdef CONFIG_BLK_DEV_INITRD |
| 232 | void free_initrd_mem(unsigned long start, unsigned long end) |
| 233 | { |
| 234 | if (start < end) |
| 235 | printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); |
| 236 | for (; start < end; start += PAGE_SIZE) { |
| 237 | ClearPageReserved(virt_to_page(start)); |
Nick Piggin | 7835e98 | 2006-03-22 00:08:40 -0800 | [diff] [blame] | 238 | init_page_count(virt_to_page(start)); |
Paul Mackerras | 14cf11a | 2005-09-26 16:04:21 +1000 | [diff] [blame] | 239 | free_page(start); |
| 240 | totalram_pages++; |
| 241 | } |
| 242 | } |
| 243 | #endif |
Ed Swarthout | df174e3 | 2007-09-21 12:53:02 +1000 | [diff] [blame] | 244 | |