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 #ifdef CONFIG_SUPERH32
28 /*
29 * Handle trivial transitions between cached and uncached
30 * segments, making use of the 1:1 mapping relationship in
31 * 512MB lowmem.
32 *
33 * This is the offset of the uncached section from its cached alias.
34 * Default value only valid in 29 bit mode, in 32bit mode will be
35 * overridden in pmb_init.
36 */
37 unsigned long cached_to_uncached = P2SEG - P1SEG;
38 #endif
39
40 #ifdef CONFIG_MMU
set_pte_phys(unsigned long addr,unsigned long phys,pgprot_t prot)41 static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot)
42 {
43 pgd_t *pgd;
44 pud_t *pud;
45 pmd_t *pmd;
46 pte_t *pte;
47
48 pgd = pgd_offset_k(addr);
49 if (pgd_none(*pgd)) {
50 pgd_ERROR(*pgd);
51 return;
52 }
53
54 pud = pud_alloc(NULL, pgd, addr);
55 if (unlikely(!pud)) {
56 pud_ERROR(*pud);
57 return;
58 }
59
60 pmd = pmd_alloc(NULL, pud, addr);
61 if (unlikely(!pmd)) {
62 pmd_ERROR(*pmd);
63 return;
64 }
65
66 pte = pte_offset_kernel(pmd, addr);
67 if (!pte_none(*pte)) {
68 pte_ERROR(*pte);
69 return;
70 }
71
72 set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot));
73 flush_tlb_one(get_asid(), addr);
74 }
75
76 /*
77 * As a performance optimization, other platforms preserve the fixmap mapping
78 * across a context switch, we don't presently do this, but this could be done
79 * in a similar fashion as to the wired TLB interface that sh64 uses (by way
80 * of the memory mapped UTLB configuration) -- this unfortunately forces us to
81 * give up a TLB entry for each mapping we want to preserve. While this may be
82 * viable for a small number of fixmaps, it's not particularly useful for
83 * everything and needs to be carefully evaluated. (ie, we may want this for
84 * the vsyscall page).
85 *
86 * XXX: Perhaps add a _PAGE_WIRED flag or something similar that we can pass
87 * in at __set_fixmap() time to determine the appropriate behavior to follow.
88 *
89 * -- PFM.
90 */
__set_fixmap(enum fixed_addresses idx,unsigned long phys,pgprot_t prot)91 void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
92 {
93 unsigned long address = __fix_to_virt(idx);
94
95 if (idx >= __end_of_fixed_addresses) {
96 BUG();
97 return;
98 }
99
100 set_pte_phys(address, phys, prot);
101 }
102
page_table_range_init(unsigned long start,unsigned long end,pgd_t * pgd_base)103 void __init page_table_range_init(unsigned long start, unsigned long end,
104 pgd_t *pgd_base)
105 {
106 pgd_t *pgd;
107 pud_t *pud;
108 pmd_t *pmd;
109 int pgd_idx;
110 unsigned long vaddr;
111
112 vaddr = start & PMD_MASK;
113 end = (end + PMD_SIZE - 1) & PMD_MASK;
114 pgd_idx = pgd_index(vaddr);
115 pgd = pgd_base + pgd_idx;
116
117 for ( ; (pgd_idx < PTRS_PER_PGD) && (vaddr != end); pgd++, pgd_idx++) {
118 BUG_ON(pgd_none(*pgd));
119 pud = pud_offset(pgd, 0);
120 BUG_ON(pud_none(*pud));
121 pmd = pmd_offset(pud, 0);
122
123 if (!pmd_present(*pmd)) {
124 pte_t *pte_table;
125 pte_table = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE);
126 pmd_populate_kernel(&init_mm, pmd, pte_table);
127 }
128
129 vaddr += PMD_SIZE;
130 }
131 }
132 #endif /* CONFIG_MMU */
133
134 /*
135 * paging_init() sets up the page tables
136 */
paging_init(void)137 void __init paging_init(void)
138 {
139 unsigned long max_zone_pfns[MAX_NR_ZONES];
140 unsigned long vaddr;
141 int nid;
142
143 /* We don't need to map the kernel through the TLB, as
144 * it is permanatly mapped using P1. So clear the
145 * entire pgd. */
146 memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
147
148 /* Set an initial value for the MMU.TTB so we don't have to
149 * check for a null value. */
150 set_TTB(swapper_pg_dir);
151
152 /*
153 * Populate the relevant portions of swapper_pg_dir so that
154 * we can use the fixmap entries without calling kmalloc.
155 * pte's will be filled in by __set_fixmap().
156 */
157 vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
158 page_table_range_init(vaddr, 0, swapper_pg_dir);
159
160 kmap_coherent_init();
161
162 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
163
164 for_each_online_node(nid) {
165 pg_data_t *pgdat = NODE_DATA(nid);
166 unsigned long low, start_pfn;
167
168 start_pfn = pgdat->bdata->node_min_pfn;
169 low = pgdat->bdata->node_low_pfn;
170
171 if (max_zone_pfns[ZONE_NORMAL] < low)
172 max_zone_pfns[ZONE_NORMAL] = low;
173
174 printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
175 nid, start_pfn, low);
176 }
177
178 free_area_init_nodes(max_zone_pfns);
179
180 #ifdef CONFIG_SUPERH32
181 /* Set up the uncached fixmap */
182 set_fixmap_nocache(FIX_UNCACHED, __pa(&__uncached_start));
183 #endif
184 }
185
186 static struct kcore_list kcore_mem, kcore_vmalloc;
187 int after_bootmem = 0;
188
mem_init(void)189 void __init mem_init(void)
190 {
191 int codesize, datasize, initsize;
192 int nid;
193
194 num_physpages = 0;
195 high_memory = NULL;
196
197 for_each_online_node(nid) {
198 pg_data_t *pgdat = NODE_DATA(nid);
199 unsigned long node_pages = 0;
200 void *node_high_memory;
201
202 num_physpages += pgdat->node_present_pages;
203
204 if (pgdat->node_spanned_pages)
205 node_pages = free_all_bootmem_node(pgdat);
206
207 totalram_pages += node_pages;
208
209 node_high_memory = (void *)__va((pgdat->node_start_pfn +
210 pgdat->node_spanned_pages) <<
211 PAGE_SHIFT);
212 if (node_high_memory > high_memory)
213 high_memory = node_high_memory;
214 }
215
216 /* clear the zero-page */
217 memset(empty_zero_page, 0, PAGE_SIZE);
218 __flush_wback_region(empty_zero_page, PAGE_SIZE);
219
220 after_bootmem = 1;
221
222 codesize = (unsigned long) &_etext - (unsigned long) &_text;
223 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
224 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
225
226 kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
227 kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
228 VMALLOC_END - VMALLOC_START);
229
230 printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, "
231 "%dk data, %dk init)\n",
232 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
233 num_physpages << (PAGE_SHIFT-10),
234 codesize >> 10,
235 datasize >> 10,
236 initsize >> 10);
237
238 p3_cache_init();
239
240 /* Initialize the vDSO */
241 vsyscall_init();
242 }
243
free_initmem(void)244 void free_initmem(void)
245 {
246 unsigned long addr;
247
248 addr = (unsigned long)(&__init_begin);
249 for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
250 ClearPageReserved(virt_to_page(addr));
251 init_page_count(virt_to_page(addr));
252 free_page(addr);
253 totalram_pages++;
254 }
255 printk("Freeing unused kernel memory: %ldk freed\n",
256 ((unsigned long)&__init_end -
257 (unsigned long)&__init_begin) >> 10);
258 }
259
260 #ifdef CONFIG_BLK_DEV_INITRD
free_initrd_mem(unsigned long start,unsigned long end)261 void free_initrd_mem(unsigned long start, unsigned long end)
262 {
263 unsigned long p;
264 for (p = start; p < end; p += PAGE_SIZE) {
265 ClearPageReserved(virt_to_page(p));
266 init_page_count(virt_to_page(p));
267 free_page(p);
268 totalram_pages++;
269 }
270 printk("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
271 }
272 #endif
273
274 #if THREAD_SHIFT < PAGE_SHIFT
275 static struct kmem_cache *thread_info_cache;
276
alloc_thread_info(struct task_struct * tsk)277 struct thread_info *alloc_thread_info(struct task_struct *tsk)
278 {
279 struct thread_info *ti;
280
281 ti = kmem_cache_alloc(thread_info_cache, GFP_KERNEL);
282 if (unlikely(ti == NULL))
283 return NULL;
284 #ifdef CONFIG_DEBUG_STACK_USAGE
285 memset(ti, 0, THREAD_SIZE);
286 #endif
287 return ti;
288 }
289
free_thread_info(struct thread_info * ti)290 void free_thread_info(struct thread_info *ti)
291 {
292 kmem_cache_free(thread_info_cache, ti);
293 }
294
thread_info_cache_init(void)295 void thread_info_cache_init(void)
296 {
297 thread_info_cache = kmem_cache_create("thread_info", THREAD_SIZE,
298 THREAD_SIZE, 0, NULL);
299 BUG_ON(thread_info_cache == NULL);
300 }
301 #endif /* THREAD_SHIFT < PAGE_SHIFT */
302
303 #ifdef CONFIG_MEMORY_HOTPLUG
arch_add_memory(int nid,u64 start,u64 size)304 int arch_add_memory(int nid, u64 start, u64 size)
305 {
306 pg_data_t *pgdat;
307 unsigned long start_pfn = start >> PAGE_SHIFT;
308 unsigned long nr_pages = size >> PAGE_SHIFT;
309 int ret;
310
311 pgdat = NODE_DATA(nid);
312
313 /* We only have ZONE_NORMAL, so this is easy.. */
314 ret = __add_pages(nid, pgdat->node_zones + ZONE_NORMAL,
315 start_pfn, nr_pages);
316 if (unlikely(ret))
317 printk("%s: Failed, __add_pages() == %d\n", __func__, ret);
318
319 return ret;
320 }
321 EXPORT_SYMBOL_GPL(arch_add_memory);
322
323 #ifdef CONFIG_NUMA
memory_add_physaddr_to_nid(u64 addr)324 int memory_add_physaddr_to_nid(u64 addr)
325 {
326 /* Node 0 for now.. */
327 return 0;
328 }
329 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
330 #endif
331 #endif /* CONFIG_MEMORY_HOTPLUG */
332