[AVR32] Fix bug in invalidate_dcache_region()
[linux-2.6.git] / arch / avr32 / mm / init.c
1 /*
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>
13 #include <linux/mmzone.h>
14 #include <linux/bootmem.h>
15 #include <linux/pagemap.h>
16 #include <linux/nodemask.h>
17
18 #include <asm/page.h>
19 #include <asm/mmu_context.h>
20 #include <asm/tlb.h>
21 #include <asm/io.h>
22 #include <asm/dma.h>
23 #include <asm/setup.h>
24 #include <asm/sections.h>
25
26 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
27
28 pgd_t swapper_pg_dir[PTRS_PER_PGD];
29
30 struct page *empty_zero_page;
31
32 /*
33  * Cache of MMU context last used.
34  */
35 unsigned long mmu_context_cache = NO_CONTEXT;
36
37 #define START_PFN       (NODE_DATA(0)->bdata->node_boot_start >> PAGE_SHIFT)
38 #define MAX_LOW_PFN     (NODE_DATA(0)->bdata->node_low_pfn)
39
40 void show_mem(void)
41 {
42         int total = 0, reserved = 0, cached = 0;
43         int slab = 0, free = 0, shared = 0;
44         pg_data_t *pgdat;
45
46         printk("Mem-info:\n");
47         show_free_areas();
48
49         for_each_online_pgdat(pgdat) {
50                 struct page *page, *end;
51
52                 page = pgdat->node_mem_map;
53                 end = page + pgdat->node_spanned_pages;
54
55                 do {
56                         total++;
57                         if (PageReserved(page))
58                                 reserved++;
59                         else if (PageSwapCache(page))
60                                 cached++;
61                         else if (PageSlab(page))
62                                 slab++;
63                         else if (!page_count(page))
64                                 free++;
65                         else
66                                 shared += page_count(page) - 1;
67                         page++;
68                 } while (page < end);
69         }
70
71         printk ("%d pages of RAM\n", total);
72         printk ("%d free pages\n", free);
73         printk ("%d reserved pages\n", reserved);
74         printk ("%d slab pages\n", slab);
75         printk ("%d pages shared\n", shared);
76         printk ("%d pages swap cached\n", cached);
77 }
78
79 /*
80  * paging_init() sets up the page tables
81  *
82  * This routine also unmaps the page at virtual kernel address 0, so
83  * that we can trap those pesky NULL-reference errors in the kernel.
84  */
85 void __init paging_init(void)
86 {
87         extern unsigned long _evba;
88         void *zero_page;
89         int nid;
90
91         /*
92          * Make sure we can handle exceptions before enabling
93          * paging. Not that we should ever _get_ any exceptions this
94          * early, but you never know...
95          */
96         printk("Exception vectors start at %p\n", &_evba);
97         sysreg_write(EVBA, (unsigned long)&_evba);
98
99         /*
100          * Since we are ready to handle exceptions now, we should let
101          * the CPU generate them...
102          */
103         __asm__ __volatile__ ("csrf %0" : : "i"(SR_EM_BIT));
104
105         /*
106          * Allocate the zero page. The allocator will panic if it
107          * can't satisfy the request, so no need to check.
108          */
109         zero_page = alloc_bootmem_low_pages_node(NODE_DATA(0),
110                                                  PAGE_SIZE);
111
112         {
113                 pgd_t *pg_dir;
114                 int i;
115
116                 pg_dir = swapper_pg_dir;
117                 sysreg_write(PTBR, (unsigned long)pg_dir);
118
119                 for (i = 0; i < PTRS_PER_PGD; i++)
120                         pgd_val(pg_dir[i]) = 0;
121
122                 enable_mmu();
123                 printk ("CPU: Paging enabled\n");
124         }
125
126         for_each_online_node(nid) {
127                 pg_data_t *pgdat = NODE_DATA(nid);
128                 unsigned long zones_size[MAX_NR_ZONES];
129                 unsigned long low, start_pfn;
130
131                 start_pfn = pgdat->bdata->node_boot_start;
132                 start_pfn >>= PAGE_SHIFT;
133                 low = pgdat->bdata->node_low_pfn;
134
135                 memset(zones_size, 0, sizeof(zones_size));
136                 zones_size[ZONE_NORMAL] = low - start_pfn;
137
138                 printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
139                        nid, start_pfn, low);
140
141                 free_area_init_node(nid, pgdat, zones_size, start_pfn, NULL);
142
143                 printk("Node %u: mem_map starts at %p\n",
144                        pgdat->node_id, pgdat->node_mem_map);
145         }
146
147         mem_map = NODE_DATA(0)->node_mem_map;
148
149         memset(zero_page, 0, PAGE_SIZE);
150         empty_zero_page = virt_to_page(zero_page);
151         flush_dcache_page(empty_zero_page);
152 }
153
154 void __init mem_init(void)
155 {
156         int codesize, reservedpages, datasize, initsize;
157         int nid, i;
158
159         reservedpages = 0;
160         high_memory = NULL;
161
162         /* this will put all low memory onto the freelists */
163         for_each_online_node(nid) {
164                 pg_data_t *pgdat = NODE_DATA(nid);
165                 unsigned long node_pages = 0;
166                 void *node_high_memory;
167
168                 num_physpages += pgdat->node_present_pages;
169
170                 if (pgdat->node_spanned_pages != 0)
171                         node_pages = free_all_bootmem_node(pgdat);
172
173                 totalram_pages += node_pages;
174
175                 for (i = 0; i < node_pages; i++)
176                         if (PageReserved(pgdat->node_mem_map + i))
177                                 reservedpages++;
178
179                 node_high_memory = (void *)((pgdat->node_start_pfn
180                                              + pgdat->node_spanned_pages)
181                                             << PAGE_SHIFT);
182                 if (node_high_memory > high_memory)
183                         high_memory = node_high_memory;
184         }
185
186         max_mapnr = MAP_NR(high_memory);
187
188         codesize = (unsigned long)_etext - (unsigned long)_text;
189         datasize = (unsigned long)_edata - (unsigned long)_data;
190         initsize = (unsigned long)__init_end - (unsigned long)__init_begin;
191
192         printk ("Memory: %luk/%luk available (%dk kernel code, "
193                 "%dk reserved, %dk data, %dk init)\n",
194                 (unsigned long)nr_free_pages() << (PAGE_SHIFT - 10),
195                 totalram_pages << (PAGE_SHIFT - 10),
196                 codesize >> 10,
197                 reservedpages << (PAGE_SHIFT - 10),
198                 datasize >> 10,
199                 initsize >> 10);
200 }
201
202 static inline void free_area(unsigned long addr, unsigned long end, char *s)
203 {
204         unsigned int size = (end - addr) >> 10;
205
206         for (; addr < end; addr += PAGE_SIZE) {
207                 struct page *page = virt_to_page(addr);
208                 ClearPageReserved(page);
209                 init_page_count(page);
210                 free_page(addr);
211                 totalram_pages++;
212         }
213
214         if (size && s)
215                 printk(KERN_INFO "Freeing %s memory: %dK (%lx - %lx)\n",
216                        s, size, end - (size << 10), end);
217 }
218
219 void free_initmem(void)
220 {
221         free_area((unsigned long)__init_begin, (unsigned long)__init_end,
222                   "init");
223 }
224
225 #ifdef CONFIG_BLK_DEV_INITRD
226
227 static int keep_initrd;
228
229 void free_initrd_mem(unsigned long start, unsigned long end)
230 {
231         if (!keep_initrd)
232                 free_area(start, end, "initrd");
233 }
234
235 static int __init keepinitrd_setup(char *__unused)
236 {
237         keep_initrd = 1;
238         return 1;
239 }
240
241 __setup("keepinitrd", keepinitrd_setup);
242 #endif