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/dma-map-ops.h>
11 #include <linux/memblock.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/mm.h> /* mem_init */
15 #include <linux/initrd.h>
16 #include <linux/of_fdt.h>
17 #include <linux/pagemap.h>
18 #include <linux/pfn.h>
19 #include <linux/slab.h>
20 #include <linux/swap.h>
21 #include <linux/export.h>
24 #include <asm/mmu_context.h>
25 #include <asm/pgalloc.h>
26 #include <asm/sections.h>
28 #include <asm/fixmap.h>
30 /* Use for MMU and noMMU because of PCI generic code */
36 * Initialize the bootmem system and give it all the memory we
39 unsigned long memory_start;
40 EXPORT_SYMBOL(memory_start);
41 unsigned long memory_size;
42 EXPORT_SYMBOL(memory_size);
43 unsigned long lowmem_size;
45 EXPORT_SYMBOL(min_low_pfn);
46 EXPORT_SYMBOL(max_low_pfn);
49 static void __init highmem_init(void)
51 pr_debug("%x\n", (u32)PKMAP_BASE);
52 map_page(PKMAP_BASE, 0, 0); /* XXX gross */
53 pkmap_page_table = virt_to_kpte(PKMAP_BASE);
56 static void __meminit highmem_setup(void)
60 for (pfn = max_low_pfn; pfn < max_pfn; ++pfn) {
61 struct page *page = pfn_to_page(pfn);
63 /* FIXME not sure about */
64 if (!memblock_is_reserved(pfn << PAGE_SHIFT))
65 free_highmem_page(page);
68 #endif /* CONFIG_HIGHMEM */
71 * paging_init() sets up the page tables - in fact we've already done this.
73 static void __init paging_init(void)
75 unsigned long zones_size[MAX_NR_ZONES];
79 for (idx = 0; idx < __end_of_fixed_addresses; idx++)
82 /* Clean every zones */
83 memset(zones_size, 0, sizeof(zones_size));
88 zones_size[ZONE_DMA] = max_low_pfn;
89 zones_size[ZONE_HIGHMEM] = max_pfn;
91 zones_size[ZONE_DMA] = max_pfn;
94 /* We don't have holes in memory map */
95 free_area_init(zones_size);
98 void __init setup_memory(void)
102 * start: base phys address of kernel - page align
103 * end: base phys address of kernel - page align
105 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start)
107 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn)
110 /* memory start is from the kernel end (aligned) to higher addr */
111 min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */
112 /* RAM is assumed contiguous */
113 max_mapnr = memory_size >> PAGE_SHIFT;
114 max_low_pfn = ((u64)memory_start + (u64)lowmem_size) >> PAGE_SHIFT;
115 max_pfn = ((u64)memory_start + (u64)memory_size) >> PAGE_SHIFT;
117 pr_info("%s: max_mapnr: %#lx\n", __func__, max_mapnr);
118 pr_info("%s: min_low_pfn: %#lx\n", __func__, min_low_pfn);
119 pr_info("%s: max_low_pfn: %#lx\n", __func__, max_low_pfn);
120 pr_info("%s: max_pfn: %#lx\n", __func__, max_pfn);
125 void __init mem_init(void)
127 high_memory = (void *)__va(memory_start + lowmem_size - 1);
129 /* this will put all memory onto the freelists */
131 #ifdef CONFIG_HIGHMEM
138 int page_is_ram(unsigned long pfn)
140 return pfn < max_low_pfn;
144 * Check for command-line options that affect what MMU_init will do.
146 static void mm_cmdline_setup(void)
148 unsigned long maxmem = 0;
151 /* Look for mem= option on command line */
152 p = strstr(cmd_line, "mem=");
155 maxmem = memparse(p, &p);
156 if (maxmem && memory_size > maxmem) {
157 memory_size = maxmem;
158 memblock.memory.regions[0].size = memory_size;
164 * MMU_init_hw does the chip-specific initialization of the MMU hardware.
166 static void __init mmu_init_hw(void)
169 * The Zone Protection Register (ZPR) defines how protection will
170 * be applied to every page which is a member of a given zone. At
171 * present, we utilize only two of the zones.
172 * The zone index bits (of ZSEL) in the PTE are used for software
173 * indicators, except the LSB. For user access, zone 1 is used,
174 * for kernel access, zone 0 is used. We set all but zone 1
175 * to zero, allowing only kernel access as indicated in the PTE.
176 * For zone 1, we set a 01 binary (a value of 10 will not work)
177 * to allow user access as indicated in the PTE. This also allows
178 * kernel access as indicated in the PTE.
180 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \
186 * MMU_init sets up the basic memory mappings for the kernel,
187 * including both RAM and possibly some I/O regions,
188 * and sets up the page tables and the MMU hardware ready to go.
191 /* called from head.S */
192 asmlinkage void __init mmu_init(void)
194 unsigned int kstart, ksize;
196 if (!memblock.reserved.cnt) {
197 pr_emerg("Error memory count\n");
198 machine_restart(NULL);
201 if ((u32) memblock.memory.regions[0].size < 0x400000) {
202 pr_emerg("Memory must be greater than 4MB\n");
203 machine_restart(NULL);
206 if ((u32) memblock.memory.regions[0].size < kernel_tlb) {
207 pr_emerg("Kernel size is greater than memory node\n");
208 machine_restart(NULL);
211 /* Find main memory where the kernel is */
212 memory_start = (u32) memblock.memory.regions[0].base;
213 lowmem_size = memory_size = (u32) memblock.memory.regions[0].size;
215 if (lowmem_size > CONFIG_LOWMEM_SIZE) {
216 lowmem_size = CONFIG_LOWMEM_SIZE;
217 #ifndef CONFIG_HIGHMEM
218 memory_size = lowmem_size;
222 mm_cmdline_setup(); /* FIXME parse args from command line - not used */
225 * Map out the kernel text/data/bss from the available physical
228 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */
230 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START));
231 memblock_reserve(kstart, ksize);
233 #if defined(CONFIG_BLK_DEV_INITRD)
234 /* Remove the init RAM disk from the available memory. */
237 size = initrd_end - initrd_start;
238 memblock_reserve(__virt_to_phys(initrd_start), size);
240 #endif /* CONFIG_BLK_DEV_INITRD */
242 /* Initialize the MMU hardware */
245 /* Map in all of RAM starting at CONFIG_KERNEL_START */
248 /* Extend vmalloc and ioremap area as big as possible */
249 #ifdef CONFIG_HIGHMEM
250 ioremap_base = ioremap_bot = PKMAP_BASE;
252 ioremap_base = ioremap_bot = FIXADDR_START;
255 /* Initialize the context management stuff */
258 /* Shortly after that, the entire linear mapping will be available */
259 /* This will also cause that unflatten device tree will be allocated
260 * inside 768MB limit */
261 memblock_set_current_limit(memory_start + lowmem_size - 1);
265 early_init_fdt_scan_reserved_mem();
267 /* CMA initialization */
268 dma_contiguous_reserve(memory_start + lowmem_size - 1);
273 void * __ref zalloc_maybe_bootmem(size_t size, gfp_t mask)
278 p = kzalloc(size, mask);
280 p = memblock_alloc(size, SMP_CACHE_BYTES);
282 panic("%s: Failed to allocate %zu bytes\n",