1 /*
2 * Copyright (C) 2007-2008 Michal Simek <monstr@monstr.eu>
3 * Copyright (C) 2006 Atmark Techno, Inc.
4 *
5 * This file is subject to the terms and conditions of the GNU General Public
6 * License. See the file "COPYING" in the main directory of this archive
7 * for more details.
8 */
9
10 #include <linux/dma-map-ops.h>
11 #include <linux/memblock.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/mm.h> /* mem_init */
15 #include <linux/initrd.h>
16 #include <linux/pagemap.h>
17 #include <linux/pfn.h>
18 #include <linux/slab.h>
19 #include <linux/swap.h>
20 #include <linux/export.h>
21
22 #include <asm/page.h>
23 #include <asm/mmu_context.h>
24 #include <asm/pgalloc.h>
25 #include <asm/sections.h>
26 #include <asm/tlb.h>
27 #include <asm/fixmap.h>
28
29 /* Use for MMU and noMMU because of PCI generic code */
30 int mem_init_done;
31
32 #ifndef CONFIG_MMU
33 unsigned int __page_offset;
34 EXPORT_SYMBOL(__page_offset);
35 #endif /* CONFIG_MMU */
36
37 char *klimit = _end;
38
39 /*
40 * Initialize the bootmem system and give it all the memory we
41 * have available.
42 */
43 unsigned long memory_start;
44 EXPORT_SYMBOL(memory_start);
45 unsigned long memory_size;
46 EXPORT_SYMBOL(memory_size);
47 unsigned long lowmem_size;
48
49 EXPORT_SYMBOL(min_low_pfn);
50 EXPORT_SYMBOL(max_low_pfn);
51
52 #ifdef CONFIG_HIGHMEM
53 pte_t *kmap_pte;
54 EXPORT_SYMBOL(kmap_pte);
55
highmem_init(void)56 static void __init highmem_init(void)
57 {
58 pr_debug("%x\n", (u32)PKMAP_BASE);
59 map_page(PKMAP_BASE, 0, 0); /* XXX gross */
60 pkmap_page_table = virt_to_kpte(PKMAP_BASE);
61
62 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
63 }
64
highmem_setup(void)65 static void highmem_setup(void)
66 {
67 unsigned long pfn;
68
69 for (pfn = max_low_pfn; pfn < max_pfn; ++pfn) {
70 struct page *page = pfn_to_page(pfn);
71
72 /* FIXME not sure about */
73 if (!memblock_is_reserved(pfn << PAGE_SHIFT))
74 free_highmem_page(page);
75 }
76 }
77 #endif /* CONFIG_HIGHMEM */
78
79 /*
80 * paging_init() sets up the page tables - in fact we've already done this.
81 */
paging_init(void)82 static void __init paging_init(void)
83 {
84 unsigned long zones_size[MAX_NR_ZONES];
85 #ifdef CONFIG_MMU
86 int idx;
87
88 /* Setup fixmaps */
89 for (idx = 0; idx < __end_of_fixed_addresses; idx++)
90 clear_fixmap(idx);
91 #endif
92
93 /* Clean every zones */
94 memset(zones_size, 0, sizeof(zones_size));
95
96 #ifdef CONFIG_HIGHMEM
97 highmem_init();
98
99 zones_size[ZONE_DMA] = max_low_pfn;
100 zones_size[ZONE_HIGHMEM] = max_pfn;
101 #else
102 zones_size[ZONE_DMA] = max_pfn;
103 #endif
104
105 /* We don't have holes in memory map */
106 free_area_init(zones_size);
107 }
108
setup_memory(void)109 void __init setup_memory(void)
110 {
111 #ifndef CONFIG_MMU
112 u32 kernel_align_start, kernel_align_size;
113 phys_addr_t start, end;
114 u64 i;
115
116 /* Find main memory where is the kernel */
117 for_each_mem_range(i, &start, &end) {
118 memory_start = start;
119 lowmem_size = end - start;
120 if ((memory_start <= (u32)_text) &&
121 ((u32)_text <= (memory_start + lowmem_size - 1))) {
122 memory_size = lowmem_size;
123 PAGE_OFFSET = memory_start;
124 pr_info("%s: Main mem: 0x%x, size 0x%08x\n",
125 __func__, (u32) memory_start,
126 (u32) memory_size);
127 break;
128 }
129 }
130
131 if (!memory_start || !memory_size) {
132 panic("%s: Missing memory setting 0x%08x, size=0x%08x\n",
133 __func__, (u32) memory_start, (u32) memory_size);
134 }
135
136 /* reservation of region where is the kernel */
137 kernel_align_start = PAGE_DOWN((u32)_text);
138 /* ALIGN can be remove because _end in vmlinux.lds.S is align */
139 kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start;
140 pr_info("%s: kernel addr:0x%08x-0x%08x size=0x%08x\n",
141 __func__, kernel_align_start, kernel_align_start
142 + kernel_align_size, kernel_align_size);
143 memblock_reserve(kernel_align_start, kernel_align_size);
144 #endif
145 /*
146 * Kernel:
147 * start: base phys address of kernel - page align
148 * end: base phys address of kernel - page align
149 *
150 * min_low_pfn - the first page (mm/bootmem.c - node_boot_start)
151 * max_low_pfn
152 * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn)
153 */
154
155 /* memory start is from the kernel end (aligned) to higher addr */
156 min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */
157 /* RAM is assumed contiguous */
158 max_mapnr = memory_size >> PAGE_SHIFT;
159 max_low_pfn = ((u64)memory_start + (u64)lowmem_size) >> PAGE_SHIFT;
160 max_pfn = ((u64)memory_start + (u64)memory_size) >> PAGE_SHIFT;
161
162 pr_info("%s: max_mapnr: %#lx\n", __func__, max_mapnr);
163 pr_info("%s: min_low_pfn: %#lx\n", __func__, min_low_pfn);
164 pr_info("%s: max_low_pfn: %#lx\n", __func__, max_low_pfn);
165 pr_info("%s: max_pfn: %#lx\n", __func__, max_pfn);
166
167 paging_init();
168 }
169
mem_init(void)170 void __init mem_init(void)
171 {
172 high_memory = (void *)__va(memory_start + lowmem_size - 1);
173
174 /* this will put all memory onto the freelists */
175 memblock_free_all();
176 #ifdef CONFIG_HIGHMEM
177 highmem_setup();
178 #endif
179
180 mem_init_print_info(NULL);
181 mem_init_done = 1;
182 }
183
184 #ifndef CONFIG_MMU
page_is_ram(unsigned long pfn)185 int page_is_ram(unsigned long pfn)
186 {
187 return __range_ok(pfn, 0);
188 }
189 #else
page_is_ram(unsigned long pfn)190 int page_is_ram(unsigned long pfn)
191 {
192 return pfn < max_low_pfn;
193 }
194
195 /*
196 * Check for command-line options that affect what MMU_init will do.
197 */
mm_cmdline_setup(void)198 static void mm_cmdline_setup(void)
199 {
200 unsigned long maxmem = 0;
201 char *p = cmd_line;
202
203 /* Look for mem= option on command line */
204 p = strstr(cmd_line, "mem=");
205 if (p) {
206 p += 4;
207 maxmem = memparse(p, &p);
208 if (maxmem && memory_size > maxmem) {
209 memory_size = maxmem;
210 memblock.memory.regions[0].size = memory_size;
211 }
212 }
213 }
214
215 /*
216 * MMU_init_hw does the chip-specific initialization of the MMU hardware.
217 */
mmu_init_hw(void)218 static void __init mmu_init_hw(void)
219 {
220 /*
221 * The Zone Protection Register (ZPR) defines how protection will
222 * be applied to every page which is a member of a given zone. At
223 * present, we utilize only two of the zones.
224 * The zone index bits (of ZSEL) in the PTE are used for software
225 * indicators, except the LSB. For user access, zone 1 is used,
226 * for kernel access, zone 0 is used. We set all but zone 1
227 * to zero, allowing only kernel access as indicated in the PTE.
228 * For zone 1, we set a 01 binary (a value of 10 will not work)
229 * to allow user access as indicated in the PTE. This also allows
230 * kernel access as indicated in the PTE.
231 */
232 __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \
233 "mts rzpr, r11;"
234 : : : "r11");
235 }
236
237 /*
238 * MMU_init sets up the basic memory mappings for the kernel,
239 * including both RAM and possibly some I/O regions,
240 * and sets up the page tables and the MMU hardware ready to go.
241 */
242
243 /* called from head.S */
mmu_init(void)244 asmlinkage void __init mmu_init(void)
245 {
246 unsigned int kstart, ksize;
247
248 if (!memblock.reserved.cnt) {
249 pr_emerg("Error memory count\n");
250 machine_restart(NULL);
251 }
252
253 if ((u32) memblock.memory.regions[0].size < 0x400000) {
254 pr_emerg("Memory must be greater than 4MB\n");
255 machine_restart(NULL);
256 }
257
258 if ((u32) memblock.memory.regions[0].size < kernel_tlb) {
259 pr_emerg("Kernel size is greater than memory node\n");
260 machine_restart(NULL);
261 }
262
263 /* Find main memory where the kernel is */
264 memory_start = (u32) memblock.memory.regions[0].base;
265 lowmem_size = memory_size = (u32) memblock.memory.regions[0].size;
266
267 if (lowmem_size > CONFIG_LOWMEM_SIZE) {
268 lowmem_size = CONFIG_LOWMEM_SIZE;
269 #ifndef CONFIG_HIGHMEM
270 memory_size = lowmem_size;
271 #endif
272 }
273
274 mm_cmdline_setup(); /* FIXME parse args from command line - not used */
275
276 /*
277 * Map out the kernel text/data/bss from the available physical
278 * memory.
279 */
280 kstart = __pa(CONFIG_KERNEL_START); /* kernel start */
281 /* kernel size */
282 ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START));
283 memblock_reserve(kstart, ksize);
284
285 #if defined(CONFIG_BLK_DEV_INITRD)
286 /* Remove the init RAM disk from the available memory. */
287 if (initrd_start) {
288 unsigned long size;
289 size = initrd_end - initrd_start;
290 memblock_reserve(__virt_to_phys(initrd_start), size);
291 }
292 #endif /* CONFIG_BLK_DEV_INITRD */
293
294 /* Initialize the MMU hardware */
295 mmu_init_hw();
296
297 /* Map in all of RAM starting at CONFIG_KERNEL_START */
298 mapin_ram();
299
300 /* Extend vmalloc and ioremap area as big as possible */
301 #ifdef CONFIG_HIGHMEM
302 ioremap_base = ioremap_bot = PKMAP_BASE;
303 #else
304 ioremap_base = ioremap_bot = FIXADDR_START;
305 #endif
306
307 /* Initialize the context management stuff */
308 mmu_context_init();
309
310 /* Shortly after that, the entire linear mapping will be available */
311 /* This will also cause that unflatten device tree will be allocated
312 * inside 768MB limit */
313 memblock_set_current_limit(memory_start + lowmem_size - 1);
314
315 parse_early_param();
316
317 /* CMA initialization */
318 dma_contiguous_reserve(memory_start + lowmem_size - 1);
319 }
320
321 /* This is only called until mem_init is done. */
early_get_page(void)322 void __init *early_get_page(void)
323 {
324 /*
325 * Mem start + kernel_tlb -> here is limit
326 * because of mem mapping from head.S
327 */
328 return memblock_alloc_try_nid_raw(PAGE_SIZE, PAGE_SIZE,
329 MEMBLOCK_LOW_LIMIT, memory_start + kernel_tlb,
330 NUMA_NO_NODE);
331 }
332
333 #endif /* CONFIG_MMU */
334
zalloc_maybe_bootmem(size_t size,gfp_t mask)335 void * __ref zalloc_maybe_bootmem(size_t size, gfp_t mask)
336 {
337 void *p;
338
339 if (mem_init_done) {
340 p = kzalloc(size, mask);
341 } else {
342 p = memblock_alloc(size, SMP_CACHE_BYTES);
343 if (!p)
344 panic("%s: Failed to allocate %zu bytes\n",
345 __func__, size);
346 }
347
348 return p;
349 }
350