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>
20 #include <linux/export.h>
23 #include <asm/mmu_context.h>
24 #include <asm/pgalloc.h>
25 #include <asm/sections.h>
27 #include <asm/fixmap.h>
29 /* Use for MMU and noMMU because of PCI generic code */
33 unsigned int __page_offset;
34 EXPORT_SYMBOL(__page_offset);
37 static int init_bootmem_done;
38 #endif /* CONFIG_MMU */
43 * Initialize the bootmem system and give it all the memory we
46 unsigned long memory_start;
47 EXPORT_SYMBOL(memory_start);
48 unsigned long memory_size;
49 EXPORT_SYMBOL(memory_size);
50 unsigned long lowmem_size;
54 EXPORT_SYMBOL(kmap_pte);
56 EXPORT_SYMBOL(kmap_prot);
58 static inline pte_t *virt_to_kpte(unsigned long vaddr)
60 return pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr),
64 static void __init highmem_init(void)
66 pr_debug("%x\n", (u32)PKMAP_BASE);
67 map_page(PKMAP_BASE, 0, 0); /* XXX gross */
68 pkmap_page_table = virt_to_kpte(PKMAP_BASE);
70 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
71 kmap_prot = PAGE_KERNEL;
74 static unsigned long highmem_setup(void)
77 unsigned long reservedpages = 0;
79 for (pfn = max_low_pfn; pfn < max_pfn; ++pfn) {
80 struct page *page = pfn_to_page(pfn);
82 /* FIXME not sure about */
83 if (memblock_is_reserved(pfn << PAGE_SHIFT))
85 free_highmem_page(page);
88 pr_info("High memory: %luk\n",
89 totalhigh_pages << (PAGE_SHIFT-10));
93 #endif /* CONFIG_HIGHMEM */
96 * paging_init() sets up the page tables - in fact we've already done this.
98 static void __init paging_init(void)
100 unsigned long zones_size[MAX_NR_ZONES];
105 for (idx = 0; idx < __end_of_fixed_addresses; idx++)
109 /* Clean every zones */
110 memset(zones_size, 0, sizeof(zones_size));
112 #ifdef CONFIG_HIGHMEM
115 zones_size[ZONE_DMA] = max_low_pfn;
116 zones_size[ZONE_HIGHMEM] = max_pfn;
118 zones_size[ZONE_DMA] = max_pfn;
121 /* We don't have holes in memory map */
122 free_area_init_nodes(zones_size);
125 void __init setup_memory(void)
127 unsigned long map_size;
128 struct memblock_region *reg;
131 u32 kernel_align_start, kernel_align_size;
133 /* Find main memory where is the kernel */
134 for_each_memblock(memory, reg) {
135 memory_start = (u32)reg->base;
136 lowmem_size = reg->size;
137 if ((memory_start <= (u32)_text) &&
138 ((u32)_text <= (memory_start + lowmem_size - 1))) {
139 memory_size = lowmem_size;
140 PAGE_OFFSET = memory_start;
141 pr_info("%s: Main mem: 0x%x, size 0x%08x\n",
142 __func__, (u32) memory_start,
148 if (!memory_start || !memory_size) {
149 panic("%s: Missing memory setting 0x%08x, size=0x%08x\n",
150 __func__, (u32) memory_start, (u32) memory_size);
153 /* reservation of region where is the kernel */
154 kernel_align_start = PAGE_DOWN((u32)_text);
155 /* ALIGN can be remove because _end in vmlinux.lds.S is align */
156 kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start;
157 pr_info("%s: kernel addr:0x%08x-0x%08x size=0x%08x\n",
158 __func__, kernel_align_start, kernel_align_start
159 + kernel_align_size, kernel_align_size);
160 memblock_reserve(kernel_align_start, kernel_align_size);
164 * start: base phys address of kernel - page align
165 * end: base phys address of kernel - page align
167 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start)
169 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn)
170 * num_physpages - number of all pages
173 /* memory start is from the kernel end (aligned) to higher addr */
174 min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */
175 /* RAM is assumed contiguous */
176 num_physpages = max_mapnr = memory_size >> PAGE_SHIFT;
177 max_low_pfn = ((u64)memory_start + (u64)lowmem_size) >> PAGE_SHIFT;
178 max_pfn = ((u64)memory_start + (u64)memory_size) >> PAGE_SHIFT;
180 pr_info("%s: max_mapnr: %#lx\n", __func__, max_mapnr);
181 pr_info("%s: min_low_pfn: %#lx\n", __func__, min_low_pfn);
182 pr_info("%s: max_low_pfn: %#lx\n", __func__, max_low_pfn);
183 pr_info("%s: max_pfn: %#lx\n", __func__, max_pfn);
186 * Find an area to use for the bootmem bitmap.
187 * We look for the first area which is at least
188 * 128kB in length (128kB is enough for a bitmap
189 * for 4GB of memory, using 4kB pages), plus 1 page
190 * (in case the address isn't page-aligned).
192 map_size = init_bootmem_node(NODE_DATA(0),
193 PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn);
194 memblock_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size);
196 /* Add active regions with valid PFNs */
197 for_each_memblock(memory, reg) {
198 unsigned long start_pfn, end_pfn;
200 start_pfn = memblock_region_memory_base_pfn(reg);
201 end_pfn = memblock_region_memory_end_pfn(reg);
202 memblock_set_node(start_pfn << PAGE_SHIFT,
203 (end_pfn - start_pfn) << PAGE_SHIFT, 0);
206 /* free bootmem is whole main memory */
207 free_bootmem_with_active_regions(0, max_low_pfn);
209 /* reserve allocate blocks */
210 for_each_memblock(reserved, reg) {
211 unsigned long top = reg->base + reg->size - 1;
213 pr_debug("reserved - 0x%08x-0x%08x, %lx, %lx\n",
214 (u32) reg->base, (u32) reg->size, top,
215 memory_start + lowmem_size - 1);
217 if (top <= (memory_start + lowmem_size - 1)) {
218 reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
219 } else if (reg->base < (memory_start + lowmem_size - 1)) {
220 unsigned long trunc_size = memory_start + lowmem_size -
222 reserve_bootmem(reg->base, trunc_size, BOOTMEM_DEFAULT);
226 /* XXX need to clip this if using highmem? */
227 sparse_memory_present_with_active_regions(0);
230 init_bootmem_done = 1;
235 #ifdef CONFIG_BLK_DEV_INITRD
236 void free_initrd_mem(unsigned long start, unsigned long end)
238 free_reserved_area(start, end, 0, "initrd");
242 void free_initmem(void)
244 free_initmem_default(0);
247 void __init mem_init(void)
250 unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize;
252 high_memory = (void *)__va(memory_start + lowmem_size - 1);
254 /* this will put all memory onto the freelists */
255 totalram_pages += free_all_bootmem();
257 for_each_online_pgdat(pgdat) {
261 for (i = 0; i < pgdat->node_spanned_pages; i++) {
262 if (!pfn_valid(pgdat->node_start_pfn + i))
264 page = pgdat_page_nr(pgdat, i);
265 if (PageReserved(page))
270 #ifdef CONFIG_HIGHMEM
271 reservedpages -= highmem_setup();
274 codesize = (unsigned long)&_sdata - (unsigned long)&_stext;
275 datasize = (unsigned long)&_edata - (unsigned long)&_sdata;
276 initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin;
277 bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start;
279 pr_info("Memory: %luk/%luk available (%luk kernel code, ",
280 nr_free_pages() << (PAGE_SHIFT-10),
281 num_physpages << (PAGE_SHIFT-10),
283 pr_cont("%luk reserved, %luk data, %luk bss, %luk init)\n",
284 reservedpages << (PAGE_SHIFT-10),
290 pr_info("Kernel virtual memory layout:\n");
291 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
292 #ifdef CONFIG_HIGHMEM
293 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
294 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
295 #endif /* CONFIG_HIGHMEM */
296 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
297 ioremap_bot, ioremap_base);
298 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
299 (unsigned long)VMALLOC_START, VMALLOC_END);
305 int page_is_ram(unsigned long pfn)
307 return __range_ok(pfn, 0);
310 int page_is_ram(unsigned long pfn)
312 return pfn < max_low_pfn;
316 * Check for command-line options that affect what MMU_init will do.
318 static void mm_cmdline_setup(void)
320 unsigned long maxmem = 0;
323 /* Look for mem= option on command line */
324 p = strstr(cmd_line, "mem=");
327 maxmem = memparse(p, &p);
328 if (maxmem && memory_size > maxmem) {
329 memory_size = maxmem;
330 memblock.memory.regions[0].size = memory_size;
336 * MMU_init_hw does the chip-specific initialization of the MMU hardware.
338 static void __init mmu_init_hw(void)
341 * The Zone Protection Register (ZPR) defines how protection will
342 * be applied to every page which is a member of a given zone. At
343 * present, we utilize only two of the zones.
344 * The zone index bits (of ZSEL) in the PTE are used for software
345 * indicators, except the LSB. For user access, zone 1 is used,
346 * for kernel access, zone 0 is used. We set all but zone 1
347 * to zero, allowing only kernel access as indicated in the PTE.
348 * For zone 1, we set a 01 binary (a value of 10 will not work)
349 * to allow user access as indicated in the PTE. This also allows
350 * kernel access as indicated in the PTE.
352 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \
358 * MMU_init sets up the basic memory mappings for the kernel,
359 * including both RAM and possibly some I/O regions,
360 * and sets up the page tables and the MMU hardware ready to go.
363 /* called from head.S */
364 asmlinkage void __init mmu_init(void)
366 unsigned int kstart, ksize;
368 if (!memblock.reserved.cnt) {
369 pr_emerg("Error memory count\n");
370 machine_restart(NULL);
373 if ((u32) memblock.memory.regions[0].size < 0x400000) {
374 pr_emerg("Memory must be greater than 4MB\n");
375 machine_restart(NULL);
378 if ((u32) memblock.memory.regions[0].size < kernel_tlb) {
379 pr_emerg("Kernel size is greater than memory node\n");
380 machine_restart(NULL);
383 /* Find main memory where the kernel is */
384 memory_start = (u32) memblock.memory.regions[0].base;
385 lowmem_size = memory_size = (u32) memblock.memory.regions[0].size;
387 if (lowmem_size > CONFIG_LOWMEM_SIZE) {
388 lowmem_size = CONFIG_LOWMEM_SIZE;
389 #ifndef CONFIG_HIGHMEM
390 memory_size = lowmem_size;
394 mm_cmdline_setup(); /* FIXME parse args from command line - not used */
397 * Map out the kernel text/data/bss from the available physical
400 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */
402 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START));
403 memblock_reserve(kstart, ksize);
405 #if defined(CONFIG_BLK_DEV_INITRD)
406 /* Remove the init RAM disk from the available memory. */
409 size = initrd_end - initrd_start;
410 memblock_reserve(virt_to_phys(initrd_start), size);
412 #endif /* CONFIG_BLK_DEV_INITRD */
414 /* Initialize the MMU hardware */
417 /* Map in all of RAM starting at CONFIG_KERNEL_START */
420 /* Extend vmalloc and ioremap area as big as possible */
421 #ifdef CONFIG_HIGHMEM
422 ioremap_base = ioremap_bot = PKMAP_BASE;
424 ioremap_base = ioremap_bot = FIXADDR_START;
427 /* Initialize the context management stuff */
430 /* Shortly after that, the entire linear mapping will be available */
431 /* This will also cause that unflatten device tree will be allocated
432 * inside 768MB limit */
433 memblock_set_current_limit(memory_start + lowmem_size - 1);
436 /* This is only called until mem_init is done. */
437 void __init *early_get_page(void)
440 if (init_bootmem_done) {
441 p = alloc_bootmem_pages(PAGE_SIZE);
444 * Mem start + kernel_tlb -> here is limit
445 * because of mem mapping from head.S
447 p = __va(memblock_alloc_base(PAGE_SIZE, PAGE_SIZE,
448 memory_start + kernel_tlb));
453 #endif /* CONFIG_MMU */
455 void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask)
458 return kmalloc(size, mask);
460 return alloc_bootmem(size);
463 void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask)
468 p = kzalloc(size, mask);
470 p = alloc_bootmem(size);