Merge branch 'for-linus' of git://git.o-hand.com/linux-rpurdie-backlight
[linux-2.6] / arch / sh / mm / init.c
1 /*
2  * linux/arch/sh/mm/init.c
3  *
4  *  Copyright (C) 1999  Niibe Yutaka
5  *  Copyright (C) 2002 - 2007  Paul Mundt
6  *
7  *  Based on linux/arch/i386/mm/init.c:
8  *   Copyright (C) 1995  Linus Torvalds
9  */
10 #include <linux/mm.h>
11 #include <linux/swap.h>
12 #include <linux/init.h>
13 #include <linux/bootmem.h>
14 #include <linux/proc_fs.h>
15 #include <linux/pagemap.h>
16 #include <linux/percpu.h>
17 #include <linux/io.h>
18 #include <asm/mmu_context.h>
19 #include <asm/tlb.h>
20 #include <asm/cacheflush.h>
21 #include <asm/sections.h>
22 #include <asm/cache.h>
23
24 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
25 pgd_t swapper_pg_dir[PTRS_PER_PGD];
26
27 void (*copy_page)(void *from, void *to);
28 void (*clear_page)(void *to);
29
30 void show_mem(void)
31 {
32         int total = 0, reserved = 0, free = 0;
33         int shared = 0, cached = 0, slab = 0;
34         pg_data_t *pgdat;
35
36         printk("Mem-info:\n");
37         show_free_areas();
38
39         for_each_online_pgdat(pgdat) {
40                 unsigned long flags, i;
41
42                 pgdat_resize_lock(pgdat, &flags);
43                 for (i = 0; i < pgdat->node_spanned_pages; i++) {
44                         struct page *page = pgdat_page_nr(pgdat, i);
45                         total++;
46                         if (PageReserved(page))
47                                 reserved++;
48                         else if (PageSwapCache(page))
49                                 cached++;
50                         else if (PageSlab(page))
51                                 slab++;
52                         else if (!page_count(page))
53                                 free++;
54                         else
55                                 shared += page_count(page) - 1;
56                 }
57                 pgdat_resize_unlock(pgdat, &flags);
58         }
59
60         printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
61         printk("%d pages of RAM\n", total);
62         printk("%d free pages\n", free);
63         printk("%d reserved pages\n", reserved);
64         printk("%d slab pages\n", slab);
65         printk("%d pages shared\n", shared);
66         printk("%d pages swap cached\n", cached);
67         printk(KERN_INFO "Total of %ld pages in page table cache\n",
68                quicklist_total_size());
69 }
70
71 #ifdef CONFIG_MMU
72 static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot)
73 {
74         pgd_t *pgd;
75         pud_t *pud;
76         pmd_t *pmd;
77         pte_t *pte;
78
79         pgd = pgd_offset_k(addr);
80         if (pgd_none(*pgd)) {
81                 pgd_ERROR(*pgd);
82                 return;
83         }
84
85         pud = pud_alloc(NULL, pgd, addr);
86         if (unlikely(!pud)) {
87                 pud_ERROR(*pud);
88                 return;
89         }
90
91         pmd = pmd_alloc(NULL, pud, addr);
92         if (unlikely(!pmd)) {
93                 pmd_ERROR(*pmd);
94                 return;
95         }
96
97         pte = pte_offset_kernel(pmd, addr);
98         if (!pte_none(*pte)) {
99                 pte_ERROR(*pte);
100                 return;
101         }
102
103         set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot));
104
105         flush_tlb_one(get_asid(), addr);
106 }
107
108 /*
109  * As a performance optimization, other platforms preserve the fixmap mapping
110  * across a context switch, we don't presently do this, but this could be done
111  * in a similar fashion as to the wired TLB interface that sh64 uses (by way
112  * of the memory mapped UTLB configuration) -- this unfortunately forces us to
113  * give up a TLB entry for each mapping we want to preserve. While this may be
114  * viable for a small number of fixmaps, it's not particularly useful for
115  * everything and needs to be carefully evaluated. (ie, we may want this for
116  * the vsyscall page).
117  *
118  * XXX: Perhaps add a _PAGE_WIRED flag or something similar that we can pass
119  * in at __set_fixmap() time to determine the appropriate behavior to follow.
120  *
121  *                                       -- PFM.
122  */
123 void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
124 {
125         unsigned long address = __fix_to_virt(idx);
126
127         if (idx >= __end_of_fixed_addresses) {
128                 BUG();
129                 return;
130         }
131
132         set_pte_phys(address, phys, prot);
133 }
134 #endif  /* CONFIG_MMU */
135
136 /*
137  * paging_init() sets up the page tables
138  */
139 void __init paging_init(void)
140 {
141         unsigned long max_zone_pfns[MAX_NR_ZONES];
142         int nid;
143
144         /* We don't need to map the kernel through the TLB, as
145          * it is permanatly mapped using P1. So clear the
146          * entire pgd. */
147         memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
148
149         /* Set an initial value for the MMU.TTB so we don't have to
150          * check for a null value. */
151         set_TTB(swapper_pg_dir);
152
153         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
154
155         for_each_online_node(nid) {
156                 pg_data_t *pgdat = NODE_DATA(nid);
157                 unsigned long low, start_pfn;
158
159                 start_pfn = pgdat->bdata->node_boot_start >> PAGE_SHIFT;
160                 low = pgdat->bdata->node_low_pfn;
161
162                 if (max_zone_pfns[ZONE_NORMAL] < low)
163                         max_zone_pfns[ZONE_NORMAL] = low;
164
165                 printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
166                        nid, start_pfn, low);
167         }
168
169         free_area_init_nodes(max_zone_pfns);
170 }
171
172 static struct kcore_list kcore_mem, kcore_vmalloc;
173
174 void __init mem_init(void)
175 {
176         int codesize, datasize, initsize;
177         int nid;
178
179         num_physpages = 0;
180         high_memory = NULL;
181
182         for_each_online_node(nid) {
183                 pg_data_t *pgdat = NODE_DATA(nid);
184                 unsigned long node_pages = 0;
185                 void *node_high_memory;
186
187                 num_physpages += pgdat->node_present_pages;
188
189                 if (pgdat->node_spanned_pages)
190                         node_pages = free_all_bootmem_node(pgdat);
191
192                 totalram_pages += node_pages;
193
194                 node_high_memory = (void *)__va((pgdat->node_start_pfn +
195                                                  pgdat->node_spanned_pages) <<
196                                                  PAGE_SHIFT);
197                 if (node_high_memory > high_memory)
198                         high_memory = node_high_memory;
199         }
200
201         /* clear the zero-page */
202         memset(empty_zero_page, 0, PAGE_SIZE);
203         __flush_wback_region(empty_zero_page, PAGE_SIZE);
204
205         /*
206          * Setup wrappers for copy/clear_page(), these will get overridden
207          * later in the boot process if a better method is available.
208          */
209 #ifdef CONFIG_MMU
210         copy_page = copy_page_slow;
211         clear_page = clear_page_slow;
212 #else
213         copy_page = copy_page_nommu;
214         clear_page = clear_page_nommu;
215 #endif
216
217         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
218         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
219         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
220
221         kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
222         kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
223                    VMALLOC_END - VMALLOC_START);
224
225         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, "
226                "%dk data, %dk init)\n",
227                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
228                 num_physpages << (PAGE_SHIFT-10),
229                 codesize >> 10,
230                 datasize >> 10,
231                 initsize >> 10);
232
233         p3_cache_init();
234
235         /* Initialize the vDSO */
236         vsyscall_init();
237 }
238
239 void free_initmem(void)
240 {
241         unsigned long addr;
242
243         addr = (unsigned long)(&__init_begin);
244         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
245                 ClearPageReserved(virt_to_page(addr));
246                 init_page_count(virt_to_page(addr));
247                 free_page(addr);
248                 totalram_pages++;
249         }
250         printk("Freeing unused kernel memory: %ldk freed\n",
251                ((unsigned long)&__init_end -
252                 (unsigned long)&__init_begin) >> 10);
253 }
254
255 #ifdef CONFIG_BLK_DEV_INITRD
256 void free_initrd_mem(unsigned long start, unsigned long end)
257 {
258         unsigned long p;
259         for (p = start; p < end; p += PAGE_SIZE) {
260                 ClearPageReserved(virt_to_page(p));
261                 init_page_count(virt_to_page(p));
262                 free_page(p);
263                 totalram_pages++;
264         }
265         printk("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
266 }
267 #endif
268
269 #ifdef CONFIG_MEMORY_HOTPLUG
270 void online_page(struct page *page)
271 {
272         ClearPageReserved(page);
273         init_page_count(page);
274         __free_page(page);
275         totalram_pages++;
276         num_physpages++;
277 }
278
279 int arch_add_memory(int nid, u64 start, u64 size)
280 {
281         pg_data_t *pgdat;
282         unsigned long start_pfn = start >> PAGE_SHIFT;
283         unsigned long nr_pages = size >> PAGE_SHIFT;
284         int ret;
285
286         pgdat = NODE_DATA(nid);
287
288         /* We only have ZONE_NORMAL, so this is easy.. */
289         ret = __add_pages(pgdat->node_zones + ZONE_NORMAL, start_pfn, nr_pages);
290         if (unlikely(ret))
291                 printk("%s: Failed, __add_pages() == %d\n", __FUNCTION__, ret);
292
293         return ret;
294 }
295 EXPORT_SYMBOL_GPL(arch_add_memory);
296
297 int remove_memory(u64 start, u64 size)
298 {
299         return -EINVAL;
300 }
301 EXPORT_SYMBOL_GPL(remove_memory);
302
303 #ifdef CONFIG_NUMA
304 int memory_add_physaddr_to_nid(u64 addr)
305 {
306         /* Node 0 for now.. */
307         return 0;
308 }
309 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
310 #endif
311 #endif