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Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -07001/*
2 * Copyright (C) 2004-2006 Atmel Corporation
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8
9#include <linux/kernel.h>
10#include <linux/mm.h>
11#include <linux/swap.h>
12#include <linux/init.h>
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -070013#include <linux/mmzone.h>
Haavard Skinnemoen8bd89742008-06-08 23:28:45 +020014#include <linux/module.h>
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -070015#include <linux/bootmem.h>
16#include <linux/pagemap.h>
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -070017#include <linux/nodemask.h>
18
19#include <asm/page.h>
20#include <asm/mmu_context.h>
21#include <asm/tlb.h>
22#include <asm/io.h>
23#include <asm/dma.h>
24#include <asm/setup.h>
25#include <asm/sections.h>
26
Haavard Skinnemoencfd23e92008-01-14 22:15:05 +010027#define __page_aligned __attribute__((section(".data.page_aligned")))
28
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -070029DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
30
Haavard Skinnemoencfd23e92008-01-14 22:15:05 +010031pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned;
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -070032
33struct page *empty_zero_page;
Haavard Skinnemoen8bd89742008-06-08 23:28:45 +020034EXPORT_SYMBOL(empty_zero_page);
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -070035
36/*
37 * Cache of MMU context last used.
38 */
39unsigned long mmu_context_cache = NO_CONTEXT;
40
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -070041/*
42 * paging_init() sets up the page tables
43 *
44 * This routine also unmaps the page at virtual kernel address 0, so
45 * that we can trap those pesky NULL-reference errors in the kernel.
46 */
47void __init paging_init(void)
48{
49 extern unsigned long _evba;
50 void *zero_page;
51 int nid;
52
53 /*
54 * Make sure we can handle exceptions before enabling
55 * paging. Not that we should ever _get_ any exceptions this
56 * early, but you never know...
57 */
58 printk("Exception vectors start at %p\n", &_evba);
59 sysreg_write(EVBA, (unsigned long)&_evba);
60
61 /*
62 * Since we are ready to handle exceptions now, we should let
63 * the CPU generate them...
64 */
65 __asm__ __volatile__ ("csrf %0" : : "i"(SR_EM_BIT));
66
67 /*
68 * Allocate the zero page. The allocator will panic if it
69 * can't satisfy the request, so no need to check.
70 */
71 zero_page = alloc_bootmem_low_pages_node(NODE_DATA(0),
72 PAGE_SIZE);
73
Haavard Skinnemoenebe74592008-01-14 22:16:50 +010074 sysreg_write(PTBR, (unsigned long)swapper_pg_dir);
75 enable_mmu();
76 printk ("CPU: Paging enabled\n");
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -070077
78 for_each_online_node(nid) {
79 pg_data_t *pgdat = NODE_DATA(nid);
80 unsigned long zones_size[MAX_NR_ZONES];
81 unsigned long low, start_pfn;
82
Johannes Weiner3560e242008-07-23 21:28:09 -070083 start_pfn = pgdat->bdata->node_min_pfn;
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -070084 low = pgdat->bdata->node_low_pfn;
85
86 memset(zones_size, 0, sizeof(zones_size));
87 zones_size[ZONE_NORMAL] = low - start_pfn;
88
89 printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
90 nid, start_pfn, low);
91
Johannes Weiner9109fb72008-07-23 21:27:20 -070092 free_area_init_node(nid, zones_size, start_pfn, NULL);
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -070093
94 printk("Node %u: mem_map starts at %p\n",
95 pgdat->node_id, pgdat->node_mem_map);
96 }
97
98 mem_map = NODE_DATA(0)->node_mem_map;
99
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -0700100 empty_zero_page = virt_to_page(zero_page);
101 flush_dcache_page(empty_zero_page);
102}
103
104void __init mem_init(void)
105{
106 int codesize, reservedpages, datasize, initsize;
107 int nid, i;
108
109 reservedpages = 0;
110 high_memory = NULL;
111
112 /* this will put all low memory onto the freelists */
113 for_each_online_node(nid) {
114 pg_data_t *pgdat = NODE_DATA(nid);
115 unsigned long node_pages = 0;
116 void *node_high_memory;
117
118 num_physpages += pgdat->node_present_pages;
119
120 if (pgdat->node_spanned_pages != 0)
121 node_pages = free_all_bootmem_node(pgdat);
122
123 totalram_pages += node_pages;
124
125 for (i = 0; i < node_pages; i++)
126 if (PageReserved(pgdat->node_mem_map + i))
127 reservedpages++;
128
129 node_high_memory = (void *)((pgdat->node_start_pfn
130 + pgdat->node_spanned_pages)
131 << PAGE_SHIFT);
132 if (node_high_memory > high_memory)
133 high_memory = node_high_memory;
134 }
135
136 max_mapnr = MAP_NR(high_memory);
137
138 codesize = (unsigned long)_etext - (unsigned long)_text;
139 datasize = (unsigned long)_edata - (unsigned long)_data;
140 initsize = (unsigned long)__init_end - (unsigned long)__init_begin;
141
142 printk ("Memory: %luk/%luk available (%dk kernel code, "
143 "%dk reserved, %dk data, %dk init)\n",
Geert Uytterhoevencc013a82009-09-21 17:02:36 -0700144 nr_free_pages() << (PAGE_SHIFT - 10),
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -0700145 totalram_pages << (PAGE_SHIFT - 10),
146 codesize >> 10,
147 reservedpages << (PAGE_SHIFT - 10),
148 datasize >> 10,
149 initsize >> 10);
150}
151
152static inline void free_area(unsigned long addr, unsigned long end, char *s)
153{
154 unsigned int size = (end - addr) >> 10;
155
156 for (; addr < end; addr += PAGE_SIZE) {
157 struct page *page = virt_to_page(addr);
158 ClearPageReserved(page);
159 init_page_count(page);
160 free_page(addr);
161 totalram_pages++;
162 }
163
164 if (size && s)
165 printk(KERN_INFO "Freeing %s memory: %dK (%lx - %lx)\n",
166 s, size, end - (size << 10), end);
167}
168
169void free_initmem(void)
170{
171 free_area((unsigned long)__init_begin, (unsigned long)__init_end,
172 "init");
173}
174
175#ifdef CONFIG_BLK_DEV_INITRD
176
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -0700177void free_initrd_mem(unsigned long start, unsigned long end)
178{
Robert P. J. Day193fdd12007-09-19 08:43:42 -0400179 free_area(start, end, "initrd");
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -0700180}
181
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -0700182#endif