2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * Copyright (C) 1994 - 2000 by Ralf Baechle
7 * Copyright (C) 1999, 2000 by Silicon Graphics
9 #include <linux/config.h>
10 #include <linux/init.h>
11 #include <linux/signal.h>
12 #include <linux/sched.h>
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/string.h>
16 #include <linux/types.h>
17 #include <linux/pagemap.h>
18 #include <linux/ptrace.h>
19 #include <linux/mman.h>
21 #include <linux/bootmem.h>
22 #include <linux/highmem.h>
23 #include <linux/swap.h>
24 #include <linux/initrd.h>
26 #include <asm/bootinfo.h>
27 #include <asm/cachectl.h>
29 #include <asm/system.h>
30 #include <asm/sections.h>
31 #include <asm/pgtable.h>
32 #include <asm/pgalloc.h>
33 #include <asm/mmu_context.h>
37 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
39 void pgd_init(unsigned long page)
41 unsigned long *p, *end;
43 p = (unsigned long *) page;
44 end = p + PTRS_PER_PGD;
47 p[0] = (unsigned long) invalid_pmd_table;
48 p[1] = (unsigned long) invalid_pmd_table;
49 p[2] = (unsigned long) invalid_pmd_table;
50 p[3] = (unsigned long) invalid_pmd_table;
51 p[4] = (unsigned long) invalid_pmd_table;
52 p[5] = (unsigned long) invalid_pmd_table;
53 p[6] = (unsigned long) invalid_pmd_table;
54 p[7] = (unsigned long) invalid_pmd_table;
59 void pmd_init(unsigned long addr, unsigned long pagetable)
61 unsigned long *p, *end;
63 p = (unsigned long *) addr;
64 end = p + PTRS_PER_PMD;
67 p[0] = (unsigned long)pagetable;
68 p[1] = (unsigned long)pagetable;
69 p[2] = (unsigned long)pagetable;
70 p[3] = (unsigned long)pagetable;
71 p[4] = (unsigned long)pagetable;
72 p[5] = (unsigned long)pagetable;
73 p[6] = (unsigned long)pagetable;
74 p[7] = (unsigned long)pagetable;
80 * We have up to 8 empty zeroed pages so we can map one of the right colour
81 * when needed. This is necessary only on R4000 / R4400 SC and MC versions
82 * where we have to avoid VCED / VECI exceptions for good performance at
83 * any price. Since page is never written to after the initialization we
84 * don't have to care about aliases on other CPUs.
86 unsigned long empty_zero_page, zero_page_mask;
88 unsigned long setup_zero_pages(void)
90 unsigned long order, size;
98 empty_zero_page = __get_free_pages(GFP_KERNEL, order);
100 panic("Oh boy, that early out of memory?");
102 page = virt_to_page(empty_zero_page);
103 while (page < virt_to_page(empty_zero_page + (PAGE_SIZE << order))) {
104 set_bit(PG_reserved, &page->flags);
105 set_page_count(page, 0);
109 size = PAGE_SIZE << order;
110 zero_page_mask = (size - 1) & PAGE_MASK;
111 memset((void *)empty_zero_page, 0, size);
116 #ifndef CONFIG_DISCONTIGMEM
117 /* References to section boundaries */
119 extern char _stext, _etext, _fdata, _edata;
120 extern char __init_begin, __init_end;
122 void __init paging_init(void)
124 pmd_t *pmd = kpmdtbl;
127 unsigned long zones_size[MAX_NR_ZONES] = {0, 0, 0};
128 unsigned long max_dma, low;
131 /* Initialize the entire pgd. */
132 pgd_init((unsigned long)swapper_pg_dir);
133 pmd_init((unsigned long)invalid_pmd_table, (unsigned long)invalid_pte_table);
134 memset((void *)invalid_pte_table, 0, sizeof(pte_t) * PTRS_PER_PTE);
136 max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
141 zones_size[ZONE_DMA] = low;
143 zones_size[ZONE_DMA] = max_dma;
144 zones_size[ZONE_NORMAL] = low - max_dma;
147 zones_size[ZONE_DMA] = low;
150 free_area_init(zones_size);
152 memset((void *)kptbl, 0, PAGE_SIZE << PGD_ORDER);
153 memset((void *)kpmdtbl, 0, PAGE_SIZE);
154 set_pgd(swapper_pg_dir, __pgd(kpmdtbl));
155 for (i = 0; i < (1 << PGD_ORDER); pmd++,i++,pte+=PTRS_PER_PTE)
156 pmd_val(*pmd) = (unsigned long)pte;
159 #define PFN_UP(x) (((x) + PAGE_SIZE - 1) >> PAGE_SHIFT)
160 #define PFN_DOWN(x) ((x) >> PAGE_SHIFT)
162 static inline int page_is_ram(unsigned long pagenr)
166 for (i = 0; i < boot_mem_map.nr_map; i++) {
167 unsigned long addr, end;
169 if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
170 /* not usable memory */
173 addr = PFN_UP(boot_mem_map.map[i].addr);
174 end = PFN_DOWN(boot_mem_map.map[i].addr +
175 boot_mem_map.map[i].size);
177 if (pagenr >= addr && pagenr < end)
184 void __init mem_init(void)
186 unsigned long codesize, reservedpages, datasize, initsize;
187 unsigned long tmp, ram;
189 max_mapnr = num_physpages = max_low_pfn;
190 high_memory = (void *) __va(max_mapnr << PAGE_SHIFT);
192 totalram_pages += free_all_bootmem();
193 totalram_pages -= setup_zero_pages(); /* Setup zeroed pages. */
195 reservedpages = ram = 0;
196 for (tmp = 0; tmp < max_low_pfn; tmp++)
197 if (page_is_ram(tmp)) {
199 if (PageReserved(mem_map+tmp))
203 codesize = (unsigned long) &_etext - (unsigned long) &_text;
204 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
205 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
207 printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
208 "%ldk reserved, %ldk data, %ldk init)\n",
209 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
210 ram << (PAGE_SHIFT-10),
212 reservedpages << (PAGE_SHIFT-10),
216 #endif /* !CONFIG_DISCONTIGMEM */
218 #ifdef CONFIG_BLK_DEV_INITRD
219 void free_initrd_mem(unsigned long start, unsigned long end)
221 /* Switch from KSEG0 to XKPHYS addresses */
222 start = (unsigned long)phys_to_virt(CPHYSADDR(start));
223 end = (unsigned long)phys_to_virt(CPHYSADDR(end));
225 printk(KERN_INFO "Freeing initrd memory: %ldk freed\n",
226 (end - start) >> 10);
228 for (; start < end; start += PAGE_SIZE) {
229 ClearPageReserved(virt_to_page(start));
230 set_page_count(virt_to_page(start), 1);
237 extern void prom_free_prom_memory(void) __init;
239 void free_initmem(void)
241 unsigned long addr, page;
243 prom_free_prom_memory();
245 addr = (unsigned long)(&__init_begin);
246 while (addr < (unsigned long)&__init_end) {
247 page = PAGE_OFFSET | CPHYSADDR(addr);
248 ClearPageReserved(virt_to_page(page));
249 set_page_count(virt_to_page(page), 1);
254 printk(KERN_INFO "Freeing unused kernel memory: %ldk freed\n",
255 (&__init_end - &__init_begin) >> 10);