2 * Copyright (C) 2007-2008 Michal Simek <monstr@monstr.eu>
3 * Copyright (C) 2006 Atmark Techno, Inc.
5 * This file is subject to the terms and conditions of the GNU General Public
6 * License. See the file "COPYING" in the main directory of this archive
10 #include <linux/bootmem.h>
11 #include <linux/init.h>
12 #include <linux/kernel.h>
13 #include <linux/memblock.h>
14 #include <linux/mm.h> /* mem_init */
15 #include <linux/initrd.h>
16 #include <linux/pagemap.h>
17 #include <linux/pfn.h>
18 #include <linux/slab.h>
19 #include <linux/swap.h>
22 #include <asm/mmu_context.h>
23 #include <asm/pgalloc.h>
24 #include <asm/sections.h>
27 /* Use for MMU and noMMU because of PCI generic code */
31 unsigned int __page_offset;
32 EXPORT_SYMBOL(__page_offset);
35 static int init_bootmem_done;
36 #endif /* CONFIG_MMU */
41 * Initialize the bootmem system and give it all the memory we
44 unsigned long memory_start;
45 EXPORT_SYMBOL(memory_start);
46 unsigned long memory_end; /* due to mm/nommu.c */
47 unsigned long memory_size;
48 EXPORT_SYMBOL(memory_size);
51 * paging_init() sets up the page tables - in fact we've already done this.
53 static void __init paging_init(void)
55 unsigned long zones_size[MAX_NR_ZONES];
57 /* Clean every zones */
58 memset(zones_size, 0, sizeof(zones_size));
61 * old: we can DMA to/from any address.put all page into ZONE_DMA
62 * We use only ZONE_NORMAL
64 zones_size[ZONE_NORMAL] = max_mapnr;
66 free_area_init(zones_size);
69 void __init setup_memory(void)
71 unsigned long map_size;
72 struct memblock_region *reg;
75 u32 kernel_align_start, kernel_align_size;
77 /* Find main memory where is the kernel */
78 for_each_memblock(memory, reg) {
79 memory_start = (u32)reg->base;
80 memory_end = (u32) reg->base + reg->size;
81 if ((memory_start <= (u32)_text) &&
82 ((u32)_text <= memory_end)) {
83 memory_size = memory_end - memory_start;
84 PAGE_OFFSET = memory_start;
85 printk(KERN_INFO "%s: Main mem: 0x%x-0x%x, "
86 "size 0x%08x\n", __func__, (u32) memory_start,
87 (u32) memory_end, (u32) memory_size);
92 if (!memory_start || !memory_end) {
93 panic("%s: Missing memory setting 0x%08x-0x%08x\n",
94 __func__, (u32) memory_start, (u32) memory_end);
97 /* reservation of region where is the kernel */
98 kernel_align_start = PAGE_DOWN((u32)_text);
99 /* ALIGN can be remove because _end in vmlinux.lds.S is align */
100 kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start;
101 memblock_reserve(kernel_align_start, kernel_align_size);
102 printk(KERN_INFO "%s: kernel addr=0x%08x-0x%08x size=0x%08x\n",
103 __func__, kernel_align_start, kernel_align_start
104 + kernel_align_size, kernel_align_size);
109 * start: base phys address of kernel - page align
110 * end: base phys address of kernel - page align
112 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start)
114 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn)
115 * num_physpages - number of all pages
118 /* memory start is from the kernel end (aligned) to higher addr */
119 min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */
120 /* RAM is assumed contiguous */
121 num_physpages = max_mapnr = memory_size >> PAGE_SHIFT;
122 max_pfn = max_low_pfn = memory_end >> PAGE_SHIFT;
124 printk(KERN_INFO "%s: max_mapnr: %#lx\n", __func__, max_mapnr);
125 printk(KERN_INFO "%s: min_low_pfn: %#lx\n", __func__, min_low_pfn);
126 printk(KERN_INFO "%s: max_low_pfn: %#lx\n", __func__, max_low_pfn);
129 * Find an area to use for the bootmem bitmap.
130 * We look for the first area which is at least
131 * 128kB in length (128kB is enough for a bitmap
132 * for 4GB of memory, using 4kB pages), plus 1 page
133 * (in case the address isn't page-aligned).
135 map_size = init_bootmem_node(NODE_DATA(0),
136 PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn);
137 memblock_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size);
139 /* free bootmem is whole main memory */
140 free_bootmem(memory_start, memory_size);
142 /* reserve allocate blocks */
143 for_each_memblock(reserved, reg) {
144 pr_debug("reserved - 0x%08x-0x%08x\n",
145 (u32) reg->base, (u32) reg->size);
146 reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
149 init_bootmem_done = 1;
154 void free_init_pages(char *what, unsigned long begin, unsigned long end)
158 for (addr = begin; addr < end; addr += PAGE_SIZE) {
159 ClearPageReserved(virt_to_page(addr));
160 init_page_count(virt_to_page(addr));
164 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
167 #ifdef CONFIG_BLK_DEV_INITRD
168 void free_initrd_mem(unsigned long start, unsigned long end)
171 for (; start < end; start += PAGE_SIZE) {
172 ClearPageReserved(virt_to_page(start));
173 init_page_count(virt_to_page(start));
178 printk(KERN_NOTICE "Freeing initrd memory: %dk freed\n",
179 (int)(pages * (PAGE_SIZE / 1024)));
183 void free_initmem(void)
185 free_init_pages("unused kernel memory",
186 (unsigned long)(&__init_begin),
187 (unsigned long)(&__init_end));
190 void __init mem_init(void)
192 high_memory = (void *)__va(memory_end);
193 /* this will put all memory onto the freelists */
194 totalram_pages += free_all_bootmem();
196 printk(KERN_INFO "Memory: %luk/%luk available\n",
197 nr_free_pages() << (PAGE_SHIFT-10),
198 num_physpages << (PAGE_SHIFT-10));
203 int page_is_ram(unsigned long pfn)
205 return __range_ok(pfn, 0);
208 int page_is_ram(unsigned long pfn)
210 return pfn < max_low_pfn;
214 * Check for command-line options that affect what MMU_init will do.
216 static void mm_cmdline_setup(void)
218 unsigned long maxmem = 0;
221 /* Look for mem= option on command line */
222 p = strstr(cmd_line, "mem=");
225 maxmem = memparse(p, &p);
226 if (maxmem && memory_size > maxmem) {
227 memory_size = maxmem;
228 memory_end = memory_start + memory_size;
229 memblock.memory.regions[0].size = memory_size;
235 * MMU_init_hw does the chip-specific initialization of the MMU hardware.
237 static void __init mmu_init_hw(void)
240 * The Zone Protection Register (ZPR) defines how protection will
241 * be applied to every page which is a member of a given zone. At
242 * present, we utilize only two of the zones.
243 * The zone index bits (of ZSEL) in the PTE are used for software
244 * indicators, except the LSB. For user access, zone 1 is used,
245 * for kernel access, zone 0 is used. We set all but zone 1
246 * to zero, allowing only kernel access as indicated in the PTE.
247 * For zone 1, we set a 01 binary (a value of 10 will not work)
248 * to allow user access as indicated in the PTE. This also allows
249 * kernel access as indicated in the PTE.
251 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \
257 * MMU_init sets up the basic memory mappings for the kernel,
258 * including both RAM and possibly some I/O regions,
259 * and sets up the page tables and the MMU hardware ready to go.
262 /* called from head.S */
263 asmlinkage void __init mmu_init(void)
265 unsigned int kstart, ksize;
267 if (!memblock.reserved.cnt) {
268 printk(KERN_EMERG "Error memory count\n");
269 machine_restart(NULL);
272 if ((u32) memblock.memory.regions[0].size < 0x1000000) {
273 printk(KERN_EMERG "Memory must be greater than 16MB\n");
274 machine_restart(NULL);
276 /* Find main memory where the kernel is */
277 memory_start = (u32) memblock.memory.regions[0].base;
278 memory_end = (u32) memblock.memory.regions[0].base +
279 (u32) memblock.memory.regions[0].size;
280 memory_size = memory_end - memory_start;
282 mm_cmdline_setup(); /* FIXME parse args from command line - not used */
285 * Map out the kernel text/data/bss from the available physical
288 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */
290 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START));
291 memblock_reserve(kstart, ksize);
293 #if defined(CONFIG_BLK_DEV_INITRD)
294 /* Remove the init RAM disk from the available memory. */
295 /* if (initrd_start) {
296 mem_pieces_remove(&phys_avail, __pa(initrd_start),
297 initrd_end - initrd_start, 1);
299 #endif /* CONFIG_BLK_DEV_INITRD */
301 /* Initialize the MMU hardware */
304 /* Map in all of RAM starting at CONFIG_KERNEL_START */
307 #ifdef HIGHMEM_START_BOOL
308 ioremap_base = HIGHMEM_START;
310 ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */
311 #endif /* CONFIG_HIGHMEM */
312 ioremap_bot = ioremap_base;
314 /* Initialize the context management stuff */
318 /* This is only called until mem_init is done. */
319 void __init *early_get_page(void)
322 if (init_bootmem_done) {
323 p = alloc_bootmem_pages(PAGE_SIZE);
326 * Mem start + 32MB -> here is limit
327 * because of mem mapping from head.S
329 p = __va(memblock_alloc_base(PAGE_SIZE, PAGE_SIZE,
330 memory_start + 0x2000000));
335 #endif /* CONFIG_MMU */
337 void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask)
340 return kmalloc(size, mask);
342 return alloc_bootmem(size);
345 void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask)
350 p = kzalloc(size, mask);
352 p = alloc_bootmem(size);