init.c revision 6bc9a3966f0395419b09b2ec90f89f7f00341b37 
1/*
2 * arch/score/mm/init.c
3 *
4 * Score Processor version.
5 *
6 * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
7 *  Lennox Wu <lennox.wu@sunplusct.com>
8 *  Chen Liqin <liqin.chen@sunplusct.com>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, see the file COPYING, or write
22 * to the Free Software Foundation, Inc.,
23 * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
24 */
25
26#include <linux/errno.h>
27#include <linux/bootmem.h>
28#include <linux/kernel.h>
29#include <linux/init.h>
30#include <linux/mm.h>
31#include <linux/mman.h>
32#include <linux/pagemap.h>
33#include <linux/proc_fs.h>
34#include <linux/sched.h>
35#include <asm-generic/sections.h>
36
37#include <asm/tlb.h>
38
39DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
40
41/*
42 * We have up to 8 empty zeroed pages so we can map one of the right colour
43 * when needed.
44 */
45unsigned long zero_page_mask;
46unsigned long empty_zero_page;
47EXPORT_SYMBOL_GPL(empty_zero_page);
48
49static struct kcore_list kcore_mem, kcore_vmalloc;
50
51unsigned long setup_zero_pages(void)
52{
53	unsigned int order = 0;
54	unsigned long size;
55	struct page *page;
56
57	empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
58	if (!empty_zero_page)
59		panic("Oh boy, that early out of memory?");
60
61	page = virt_to_page((void *) empty_zero_page);
62	split_page(page, order);
63	while (page < virt_to_page((void *) (empty_zero_page +
64					     (PAGE_SIZE << order)))) {
65		SetPageReserved(page);
66		page++;
67	}
68
69	size = PAGE_SIZE << order;
70	zero_page_mask = (size - 1) & PAGE_MASK;
71
72	return 1UL << order;
73}
74
75#ifndef CONFIG_NEED_MULTIPLE_NODES
76static int __init page_is_ram(unsigned long pagenr)
77{
78	if (pagenr >= min_low_pfn && pagenr < max_low_pfn)
79		return 1;
80	else
81		return 0;
82}
83
84void __init paging_init(void)
85{
86	unsigned long max_zone_pfns[MAX_NR_ZONES];
87	unsigned long lastpfn;
88
89	pagetable_init();
90	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
91	lastpfn = max_low_pfn;
92	free_area_init_nodes(max_zone_pfns);
93}
94
95void __init mem_init(void)
96{
97	unsigned long codesize, reservedpages, datasize, initsize;
98	unsigned long tmp, ram = 0;
99
100	max_mapnr = max_low_pfn;
101	high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
102	totalram_pages += free_all_bootmem();
103	totalram_pages -= setup_zero_pages();	/* Setup zeroed pages. */
104	reservedpages = 0;
105
106	for (tmp = 0; tmp < max_low_pfn; tmp++)
107		if (page_is_ram(tmp)) {
108			ram++;
109			if (PageReserved(pfn_to_page(tmp)))
110				reservedpages++;
111		}
112
113	num_physpages = ram;
114	codesize = (unsigned long) &_etext - (unsigned long) &_text;
115	datasize = (unsigned long) &_edata - (unsigned long) &_etext;
116	initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
117
118	kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
119	kclist_add(&kcore_vmalloc, (void *) VMALLOC_START,
120			VMALLOC_END - VMALLOC_START);
121
122	printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
123			"%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
124			(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
125			ram << (PAGE_SHIFT-10), codesize >> 10,
126			reservedpages << (PAGE_SHIFT-10), datasize >> 10,
127			initsize >> 10,
128			(unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
129}
130#endif /* !CONFIG_NEED_MULTIPLE_NODES */
131
132void free_init_pages(const char *what, unsigned long begin, unsigned long end)
133{
134	unsigned long pfn;
135
136	for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
137		struct page *page = pfn_to_page(pfn);
138		void *addr = phys_to_virt(PFN_PHYS(pfn));
139
140		ClearPageReserved(page);
141		init_page_count(page);
142		memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
143		__free_page(page);
144		totalram_pages++;
145	}
146	printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
147}
148
149#ifdef CONFIG_BLK_DEV_INITRD
150void free_initrd_mem(unsigned long start, unsigned long end)
151{
152	free_init_pages("initrd memory",
153	virt_to_phys((void *) start),
154	virt_to_phys((void *) end));
155}
156#endif
157
158void __init_refok free_initmem(void)
159{
160	free_init_pages("unused kernel memory",
161	    (unsigned long)__init_begin, (unsigned long)__init_end);
162}
163
164unsigned long pgd_current;
165
166#define __page_aligned(order) __attribute__((__aligned__(PAGE_SIZE<<order)))
167
168/*
169 * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER
170 * are constants.  So we use the variants from asm-offset.h until that gcc
171 * will officially be retired.
172 */
173pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER);
174