File: /usr/src/linux/arch/sh/mm/init.c
1 /* $Id: init.c,v 1.18 2001/08/03 11:22:06 gniibe Exp $
2 *
3 * linux/arch/sh/mm/init.c
4 *
5 * Copyright (C) 1999 Niibe Yutaka
6 *
7 * Based on linux/arch/i386/mm/init.c:
8 * Copyright (C) 1995 Linus Torvalds
9 */
10
11 #include <linux/config.h>
12 #include <linux/signal.h>
13 #include <linux/sched.h>
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/string.h>
17 #include <linux/types.h>
18 #include <linux/ptrace.h>
19 #include <linux/mman.h>
20 #include <linux/mm.h>
21 #include <linux/swap.h>
22 #include <linux/smp.h>
23 #include <linux/init.h>
24 #ifdef CONFIG_BLK_DEV_INITRD
25 #include <linux/blk.h>
26 #endif
27 #include <linux/highmem.h>
28 #include <linux/bootmem.h>
29
30 #include <asm/processor.h>
31 #include <asm/system.h>
32 #include <asm/uaccess.h>
33 #include <asm/pgtable.h>
34 #include <asm/pgalloc.h>
35 #include <asm/mmu_context.h>
36 #include <asm/io.h>
37 #include <asm/tlb.h>
38
39 mmu_gather_t mmu_gathers[NR_CPUS];
40
41 /*
42 * Cache of MMU context last used.
43 */
44 unsigned long mmu_context_cache;
45
46 #ifdef CONFIG_DISCONTIGMEM
47 pg_data_t discontig_page_data[NR_NODES];
48 bootmem_data_t discontig_node_bdata[NR_NODES];
49 #endif
50
51 static unsigned long totalram_pages;
52 static unsigned long totalhigh_pages;
53
54 void show_mem(void)
55 {
56 int i, total = 0, reserved = 0;
57 int shared = 0, cached = 0;
58
59 printk("Mem-info:\n");
60 show_free_areas();
61 printk("Free swap: %6dkB\n",nr_swap_pages<<(PAGE_SHIFT-10));
62 i = max_mapnr;
63 while (i-- > 0) {
64 total++;
65 if (PageReserved(mem_map+i))
66 reserved++;
67 else if (PageSwapCache(mem_map+i))
68 cached++;
69 else if (page_count(mem_map+i))
70 shared += page_count(mem_map+i) - 1;
71 }
72 printk("%d pages of RAM\n",total);
73 printk("%d reserved pages\n",reserved);
74 printk("%d pages shared\n",shared);
75 printk("%d pages swap cached\n",cached);
76 show_buffers();
77 }
78
79 /* References to section boundaries */
80
81 extern char _text, _etext, _edata, __bss_start, _end;
82 extern char __init_begin, __init_end;
83
84 pgd_t swapper_pg_dir[PTRS_PER_PGD];
85
86 /* It'd be good if these lines were in the standard header file. */
87 #define START_PFN (NODE_DATA(0)->bdata->node_boot_start >> PAGE_SHIFT)
88 #define MAX_LOW_PFN (NODE_DATA(0)->bdata->node_low_pfn)
89
90 /*
91 * paging_init() sets up the page tables
92 *
93 * This routines also unmaps the page at virtual kernel address 0, so
94 * that we can trap those pesky NULL-reference errors in the kernel.
95 */
96 void __init paging_init(void)
97 {
98 int i;
99 pgd_t * pg_dir;
100
101 /* We don't need kernel mapping as hardware support that. */
102 pg_dir = swapper_pg_dir;
103
104 for (i=0; i < PTRS_PER_PGD; i++)
105 pgd_val(pg_dir[i]) = 0;
106
107 /* Enable MMU */
108 ctrl_outl(MMU_CONTROL_INIT, MMUCR);
109
110 /* The manual suggests doing some nops after turning on the MMU */
111 asm volatile("nop;nop;nop;nop;nop;nop;");
112
113 mmu_context_cache = MMU_CONTEXT_FIRST_VERSION;
114 set_asid(mmu_context_cache & MMU_CONTEXT_ASID_MASK);
115
116 {
117 unsigned long zones_size[MAX_NR_ZONES] = {0, 0, 0};
118 unsigned long max_dma, low, start_pfn;
119
120 start_pfn = START_PFN;
121 max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
122 low = MAX_LOW_PFN;
123
124 if (low < max_dma)
125 zones_size[ZONE_DMA] = low - start_pfn;
126 else {
127 zones_size[ZONE_DMA] = max_dma - start_pfn;
128 zones_size[ZONE_NORMAL] = low - max_dma;
129 }
130 free_area_init_node(0, NODE_DATA(0), 0, zones_size, __MEMORY_START, 0);
131 #ifdef CONFIG_DISCONTIGMEM
132 zones_size[ZONE_DMA] = __MEMORY_SIZE_2ND >> PAGE_SHIFT;
133 zones_size[ZONE_NORMAL] = 0;
134 free_area_init_node(1, NODE_DATA(1), 0, zones_size, __MEMORY_START_2ND, 0);
135 #endif
136 }
137 }
138
139 void __init mem_init(void)
140 {
141 extern unsigned long empty_zero_page[1024];
142 int codesize, reservedpages, datasize, initsize;
143 int tmp;
144
145 max_mapnr = num_physpages = MAX_LOW_PFN - START_PFN;
146 high_memory = (void *)__va(MAX_LOW_PFN * PAGE_SIZE);
147
148 /* clear the zero-page */
149 memset(empty_zero_page, 0, PAGE_SIZE);
150 __flush_wback_region(empty_zero_page, PAGE_SIZE);
151
152 /* this will put all low memory onto the freelists */
153 totalram_pages += free_all_bootmem_node(NODE_DATA(0));
154 #ifdef CONFIG_DISCONTIGMEM
155 totalram_pages += free_all_bootmem_node(NODE_DATA(1));
156 #endif
157 reservedpages = 0;
158 for (tmp = 0; tmp < num_physpages; tmp++)
159 /*
160 * Only count reserved RAM pages
161 */
162 if (PageReserved(mem_map+tmp))
163 reservedpages++;
164 codesize = (unsigned long) &_etext - (unsigned long) &_text;
165 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
166 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
167
168 printk("Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init)\n",
169 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
170 max_mapnr << (PAGE_SHIFT-10),
171 codesize >> 10,
172 reservedpages << (PAGE_SHIFT-10),
173 datasize >> 10,
174 initsize >> 10);
175
176 p3_cache_init();
177 }
178
179 void free_initmem(void)
180 {
181 unsigned long addr;
182
183 addr = (unsigned long)(&__init_begin);
184 for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
185 ClearPageReserved(virt_to_page(addr));
186 set_page_count(virt_to_page(addr), 1);
187 free_page(addr);
188 totalram_pages++;
189 }
190 printk ("Freeing unused kernel memory: %dk freed\n", (&__init_end - &__init_begin) >> 10);
191 }
192
193 #ifdef CONFIG_BLK_DEV_INITRD
194 void free_initrd_mem(unsigned long start, unsigned long end)
195 {
196 unsigned long p;
197 for (p = start; p < end; p += PAGE_SIZE) {
198 ClearPageReserved(virt_to_page(p));
199 set_page_count(virt_to_page(p), 1);
200 free_page(p);
201 totalram_pages++;
202 }
203 printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
204 }
205 #endif
206
207 void si_meminfo(struct sysinfo *val)
208 {
209 val->totalram = totalram_pages;
210 val->sharedram = 0;
211 val->freeram = nr_free_pages();
212 val->bufferram = atomic_read(&buffermem_pages);
213 val->totalhigh = totalhigh_pages;
214 val->freehigh = nr_free_highpages();
215 val->mem_unit = PAGE_SIZE;
216 return;
217 }
218