init.c revision b920de1b77b72ca9432ac3f97edb26541e65e5dd 
1/* MN10300 Memory management initialisation
2 *
3 * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5 * Modified by David Howells (dhowells@redhat.com)
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public Licence
9 * as published by the Free Software Foundation; either version
10 * 2 of the Licence, or (at your option) any later version.
11 */
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/slab.h>
21#include <linux/fs.h>
22#include <linux/mm.h>
23#include <linux/swap.h>
24#include <linux/smp.h>
25#include <linux/init.h>
26#include <linux/initrd.h>
27#include <linux/highmem.h>
28#include <linux/pagemap.h>
29#include <linux/bootmem.h>
30
31#include <asm/processor.h>
32#include <asm/system.h>
33#include <asm/uaccess.h>
34#include <asm/pgtable.h>
35#include <asm/pgalloc.h>
36#include <asm/dma.h>
37#include <asm/tlb.h>
38#include <asm/sections.h>
39
40DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
41
42unsigned long highstart_pfn, highend_pfn;
43
44/*
45 * set up paging
46 */
47void __init paging_init(void)
48{
49	unsigned long zones_size[MAX_NR_ZONES] = {0,};
50	pte_t *ppte;
51	int loop;
52
53	/* main kernel space -> RAM mapping is handled as 1:1 transparent by
54	 * the MMU */
55	memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
56	memset(kernel_vmalloc_ptes, 0, sizeof(kernel_vmalloc_ptes));
57
58	/* load the VMALLOC area PTE table addresses into the kernel PGD */
59	ppte = kernel_vmalloc_ptes;
60	for (loop = VMALLOC_START / (PAGE_SIZE * PTRS_PER_PTE);
61	     loop < VMALLOC_END / (PAGE_SIZE * PTRS_PER_PTE);
62	     loop++
63	     ) {
64		set_pgd(swapper_pg_dir + loop, __pgd(__pa(ppte) | _PAGE_TABLE));
65		ppte += PAGE_SIZE / sizeof(pte_t);
66	}
67
68	/* declare the sizes of the RAM zones (only use the normal zone) */
69	zones_size[ZONE_NORMAL] =
70		(contig_page_data.bdata->node_low_pfn) -
71		(contig_page_data.bdata->node_boot_start >> PAGE_SHIFT);
72
73	/* pass the memory from the bootmem allocator to the main allocator */
74	free_area_init(zones_size);
75
76	__flush_tlb_all();
77}
78
79/*
80 * transfer all the memory from the bootmem allocator to the runtime allocator
81 */
82void __init mem_init(void)
83{
84	int codesize, reservedpages, datasize, initsize;
85	int tmp;
86
87	if (!mem_map)
88		BUG();
89
90#define START_PFN	(contig_page_data.bdata->node_boot_start >> PAGE_SHIFT)
91#define MAX_LOW_PFN	(contig_page_data.bdata->node_low_pfn)
92
93	max_mapnr = num_physpages = MAX_LOW_PFN - START_PFN;
94	high_memory = (void *) __va(MAX_LOW_PFN * PAGE_SIZE);
95
96	/* clear the zero-page */
97	memset(empty_zero_page, 0, PAGE_SIZE);
98
99	/* this will put all low memory onto the freelists */
100	totalram_pages += free_all_bootmem();
101
102	reservedpages = 0;
103	for (tmp = 0; tmp < num_physpages; tmp++)
104		if (PageReserved(&mem_map[tmp]))
105			reservedpages++;
106
107	codesize =  (unsigned long) &_etext - (unsigned long) &_stext;
108	datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
109	initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
110
111	printk(KERN_INFO
112	       "Memory: %luk/%luk available"
113	       " (%dk kernel code, %dk reserved, %dk data, %dk init,"
114	       " %ldk highmem)\n",
115	       (unsigned long) nr_free_pages() << (PAGE_SHIFT - 10),
116	       max_mapnr << (PAGE_SHIFT - 10),
117	       codesize >> 10,
118	       reservedpages << (PAGE_SHIFT - 10),
119	       datasize >> 10,
120	       initsize >> 10,
121	       (unsigned long) (totalhigh_pages << (PAGE_SHIFT - 10))
122	       );
123}
124
125/*
126 *
127 */
128void free_init_pages(char *what, unsigned long begin, unsigned long end)
129{
130	unsigned long addr;
131
132	for (addr = begin; addr < end; addr += PAGE_SIZE) {
133		ClearPageReserved(virt_to_page(addr));
134		init_page_count(virt_to_page(addr));
135		memset((void *) addr, 0xcc, PAGE_SIZE);
136		free_page(addr);
137		totalram_pages++;
138	}
139	printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
140}
141
142/*
143 * recycle memory containing stuff only required for initialisation
144 */
145void free_initmem(void)
146{
147	free_init_pages("unused kernel memory",
148			(unsigned long) &__init_begin,
149			(unsigned long) &__init_end);
150}
151
152/*
153 * dispose of the memory on which the initial ramdisk resided
154 */
155#ifdef CONFIG_BLK_DEV_INITRD
156void free_initrd_mem(unsigned long start, unsigned long end)
157{
158	free_init_pages("initrd memory", start, end);
159}
160#endif
161