Commit | Line | Data |
---|---|---|
3f65ce4d CZ |
1 | /* |
2 | * arch/xtensa/mm/init.c | |
3 | * | |
4 | * Derived from MIPS, PPC. | |
5 | * | |
6 | * This file is subject to the terms and conditions of the GNU General Public | |
7 | * License. See the file "COPYING" in the main directory of this archive | |
8 | * for more details. | |
9 | * | |
10 | * Copyright (C) 2001 - 2005 Tensilica Inc. | |
11 | * | |
12 | * Chris Zankel <chris@zankel.net> | |
13 | * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com> | |
14 | * Marc Gauthier | |
15 | * Kevin Chea | |
16 | */ | |
17 | ||
3f65ce4d CZ |
18 | #include <linux/kernel.h> |
19 | #include <linux/errno.h> | |
3f65ce4d CZ |
20 | #include <linux/bootmem.h> |
21 | #include <linux/swap.h> | |
6656920b CZ |
22 | #include <linux/mman.h> |
23 | #include <linux/nodemask.h> | |
24 | #include <linux/mm.h> | |
25 | #include <linux/slab.h> | |
3f65ce4d CZ |
26 | |
27 | #include <asm/pgtable.h> | |
28 | #include <asm/bootparam.h> | |
29 | #include <asm/mmu_context.h> | |
30 | #include <asm/tlb.h> | |
3f65ce4d CZ |
31 | #include <asm/page.h> |
32 | #include <asm/pgalloc.h> | |
3f65ce4d | 33 | |
3f65ce4d CZ |
34 | |
35 | DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); | |
3f65ce4d CZ |
36 | |
37 | /* References to section boundaries */ | |
38 | ||
39 | extern char _ftext, _etext, _fdata, _edata, _rodata_end; | |
40 | extern char __init_begin, __init_end; | |
41 | ||
42 | /* | |
43 | * mem_reserve(start, end, must_exist) | |
44 | * | |
45 | * Reserve some memory from the memory pool. | |
46 | * | |
47 | * Parameters: | |
48 | * start Start of region, | |
49 | * end End of region, | |
50 | * must_exist Must exist in memory pool. | |
51 | * | |
52 | * Returns: | |
53 | * 0 (memory area couldn't be mapped) | |
54 | * -1 (success) | |
55 | */ | |
56 | ||
57 | int __init mem_reserve(unsigned long start, unsigned long end, int must_exist) | |
58 | { | |
59 | int i; | |
60 | ||
61 | if (start == end) | |
62 | return 0; | |
63 | ||
64 | start = start & PAGE_MASK; | |
65 | end = PAGE_ALIGN(end); | |
66 | ||
67 | for (i = 0; i < sysmem.nr_banks; i++) | |
68 | if (start < sysmem.bank[i].end | |
69 | && end >= sysmem.bank[i].start) | |
70 | break; | |
71 | ||
72 | if (i == sysmem.nr_banks) { | |
73 | if (must_exist) | |
74 | printk (KERN_WARNING "mem_reserve: [0x%0lx, 0x%0lx) " | |
75 | "not in any region!\n", start, end); | |
76 | return 0; | |
77 | } | |
78 | ||
79 | if (start > sysmem.bank[i].start) { | |
80 | if (end < sysmem.bank[i].end) { | |
81 | /* split entry */ | |
82 | if (sysmem.nr_banks >= SYSMEM_BANKS_MAX) | |
83 | panic("meminfo overflow\n"); | |
84 | sysmem.bank[sysmem.nr_banks].start = end; | |
85 | sysmem.bank[sysmem.nr_banks].end = sysmem.bank[i].end; | |
86 | sysmem.nr_banks++; | |
87 | } | |
88 | sysmem.bank[i].end = start; | |
89 | } else { | |
90 | if (end < sysmem.bank[i].end) | |
91 | sysmem.bank[i].start = end; | |
92 | else { | |
93 | /* remove entry */ | |
94 | sysmem.nr_banks--; | |
95 | sysmem.bank[i].start = sysmem.bank[sysmem.nr_banks].start; | |
96 | sysmem.bank[i].end = sysmem.bank[sysmem.nr_banks].end; | |
97 | } | |
98 | } | |
99 | return -1; | |
100 | } | |
101 | ||
102 | ||
103 | /* | |
104 | * Initialize the bootmem system and give it all the memory we have available. | |
105 | */ | |
106 | ||
107 | void __init bootmem_init(void) | |
108 | { | |
109 | unsigned long pfn; | |
110 | unsigned long bootmap_start, bootmap_size; | |
111 | int i; | |
112 | ||
113 | max_low_pfn = max_pfn = 0; | |
114 | min_low_pfn = ~0; | |
115 | ||
116 | for (i=0; i < sysmem.nr_banks; i++) { | |
117 | pfn = PAGE_ALIGN(sysmem.bank[i].start) >> PAGE_SHIFT; | |
118 | if (pfn < min_low_pfn) | |
119 | min_low_pfn = pfn; | |
120 | pfn = PAGE_ALIGN(sysmem.bank[i].end - 1) >> PAGE_SHIFT; | |
121 | if (pfn > max_pfn) | |
122 | max_pfn = pfn; | |
123 | } | |
124 | ||
125 | if (min_low_pfn > max_pfn) | |
126 | panic("No memory found!\n"); | |
127 | ||
173d6681 CZ |
128 | max_low_pfn = max_pfn < MAX_MEM_PFN >> PAGE_SHIFT ? |
129 | max_pfn : MAX_MEM_PFN >> PAGE_SHIFT; | |
3f65ce4d CZ |
130 | |
131 | /* Find an area to use for the bootmem bitmap. */ | |
132 | ||
133 | bootmap_size = bootmem_bootmap_pages(max_low_pfn) << PAGE_SHIFT; | |
134 | bootmap_start = ~0; | |
135 | ||
136 | for (i=0; i<sysmem.nr_banks; i++) | |
137 | if (sysmem.bank[i].end - sysmem.bank[i].start >= bootmap_size) { | |
138 | bootmap_start = sysmem.bank[i].start; | |
139 | break; | |
140 | } | |
141 | ||
142 | if (bootmap_start == ~0UL) | |
143 | panic("Cannot find %ld bytes for bootmap\n", bootmap_size); | |
144 | ||
145 | /* Reserve the bootmem bitmap area */ | |
146 | ||
147 | mem_reserve(bootmap_start, bootmap_start + bootmap_size, 1); | |
148 | bootmap_size = init_bootmem_node(NODE_DATA(0), min_low_pfn, | |
149 | bootmap_start >> PAGE_SHIFT, | |
150 | max_low_pfn); | |
151 | ||
152 | /* Add all remaining memory pieces into the bootmem map */ | |
153 | ||
154 | for (i=0; i<sysmem.nr_banks; i++) | |
155 | free_bootmem(sysmem.bank[i].start, | |
156 | sysmem.bank[i].end - sysmem.bank[i].start); | |
157 | ||
158 | } | |
159 | ||
160 | ||
161 | void __init paging_init(void) | |
162 | { | |
163 | unsigned long zones_size[MAX_NR_ZONES]; | |
164 | int i; | |
165 | ||
166 | /* All pages are DMA-able, so we put them all in the DMA zone. */ | |
167 | ||
168 | zones_size[ZONE_DMA] = max_low_pfn; | |
169 | for (i = 1; i < MAX_NR_ZONES; i++) | |
170 | zones_size[i] = 0; | |
171 | ||
172 | #ifdef CONFIG_HIGHMEM | |
173 | zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn; | |
174 | #endif | |
175 | ||
176 | /* Initialize the kernel's page tables. */ | |
177 | ||
178 | memset(swapper_pg_dir, 0, PAGE_SIZE); | |
179 | ||
180 | free_area_init(zones_size); | |
181 | } | |
182 | ||
183 | /* | |
184 | * Flush the mmu and reset associated register to default values. | |
185 | */ | |
186 | ||
187 | void __init init_mmu (void) | |
188 | { | |
189 | /* Writing zeros to the <t>TLBCFG special registers ensure | |
190 | * that valid values exist in the register. For existing | |
191 | * PGSZID<w> fields, zero selects the first element of the | |
4af410a8 | 192 | * page-size array. For nonexistent PGSZID<w> fields, zero is |
3f65ce4d CZ |
193 | * the best value to write. Also, when changing PGSZID<w> |
194 | * fields, the corresponding TLB must be flushed. | |
195 | */ | |
196 | set_itlbcfg_register (0); | |
197 | set_dtlbcfg_register (0); | |
198 | flush_tlb_all (); | |
199 | ||
200 | /* Set rasid register to a known value. */ | |
201 | ||
173d6681 | 202 | set_rasid_register (ASID_USER_FIRST); |
3f65ce4d CZ |
203 | |
204 | /* Set PTEVADDR special register to the start of the page | |
205 | * table, which is in kernel mappable space (ie. not | |
206 | * statically mapped). This register's value is undefined on | |
207 | * reset. | |
208 | */ | |
209 | set_ptevaddr_register (PGTABLE_START); | |
210 | } | |
211 | ||
212 | /* | |
213 | * Initialize memory pages. | |
214 | */ | |
215 | ||
216 | void __init mem_init(void) | |
217 | { | |
218 | unsigned long codesize, reservedpages, datasize, initsize; | |
219 | unsigned long highmemsize, tmp, ram; | |
220 | ||
221 | max_mapnr = num_physpages = max_low_pfn; | |
222 | high_memory = (void *) __va(max_mapnr << PAGE_SHIFT); | |
223 | highmemsize = 0; | |
224 | ||
288a60cf | 225 | #ifdef CONFIG_HIGHMEM |
3f65ce4d CZ |
226 | #error HIGHGMEM not implemented in init.c |
227 | #endif | |
228 | ||
229 | totalram_pages += free_all_bootmem(); | |
230 | ||
231 | reservedpages = ram = 0; | |
232 | for (tmp = 0; tmp < max_low_pfn; tmp++) { | |
233 | ram++; | |
234 | if (PageReserved(mem_map+tmp)) | |
235 | reservedpages++; | |
236 | } | |
237 | ||
238 | codesize = (unsigned long) &_etext - (unsigned long) &_ftext; | |
239 | datasize = (unsigned long) &_edata - (unsigned long) &_fdata; | |
240 | initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; | |
241 | ||
242 | printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, " | |
243 | "%ldk data, %ldk init %ldk highmem)\n", | |
244 | (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), | |
245 | ram << (PAGE_SHIFT-10), | |
246 | codesize >> 10, | |
247 | reservedpages << (PAGE_SHIFT-10), | |
248 | datasize >> 10, | |
249 | initsize >> 10, | |
250 | highmemsize >> 10); | |
251 | } | |
252 | ||
253 | void | |
254 | free_reserved_mem(void *start, void *end) | |
255 | { | |
256 | for (; start < end; start += PAGE_SIZE) { | |
257 | ClearPageReserved(virt_to_page(start)); | |
7835e98b | 258 | init_page_count(virt_to_page(start)); |
3f65ce4d CZ |
259 | free_page((unsigned long)start); |
260 | totalram_pages++; | |
261 | } | |
262 | } | |
263 | ||
264 | #ifdef CONFIG_BLK_DEV_INITRD | |
265 | extern int initrd_is_mapped; | |
266 | ||
267 | void free_initrd_mem(unsigned long start, unsigned long end) | |
268 | { | |
269 | if (initrd_is_mapped) { | |
270 | free_reserved_mem((void*)start, (void*)end); | |
271 | printk ("Freeing initrd memory: %ldk freed\n",(end-start)>>10); | |
272 | } | |
273 | } | |
274 | #endif | |
275 | ||
276 | void free_initmem(void) | |
277 | { | |
278 | free_reserved_mem(&__init_begin, &__init_end); | |
279 | printk("Freeing unused kernel memory: %dk freed\n", | |
280 | (&__init_end - &__init_begin) >> 10); | |
281 | } | |
282 | ||
6656920b | 283 | struct kmem_cache *pgtable_cache __read_mostly; |
3f65ce4d | 284 | |
51cc5068 | 285 | static void pgd_ctor(void* addr) |
3f65ce4d | 286 | { |
6656920b CZ |
287 | pte_t* ptep = (pte_t*)addr; |
288 | int i; | |
3f65ce4d | 289 | |
6656920b CZ |
290 | for (i = 0; i < 1024; i++, ptep++) |
291 | pte_clear(NULL, 0, ptep); | |
3f65ce4d | 292 | |
3f65ce4d CZ |
293 | } |
294 | ||
6656920b | 295 | void __init pgtable_cache_init(void) |
3f65ce4d | 296 | { |
6656920b CZ |
297 | pgtable_cache = kmem_cache_create("pgd", |
298 | PAGE_SIZE, PAGE_SIZE, | |
299 | SLAB_HWCACHE_ALIGN, | |
300 | pgd_ctor); | |
3f65ce4d | 301 | } |