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/gfp.h>
 30#include <linux/init.h>
 31#include <linux/mm.h>
 32#include <linux/mman.h>
 33#include <linux/pagemap.h>
 34#include <linux/proc_fs.h>
 35#include <linux/sched.h>
 36#include <linux/initrd.h>
 37
 38#include <asm/sections.h>
 39#include <asm/tlb.h>
 40
 41unsigned long empty_zero_page;
 42EXPORT_SYMBOL_GPL(empty_zero_page);
 43
 44static struct kcore_list kcore_mem, kcore_vmalloc;
 45
 46static unsigned long setup_zero_page(void)
 47{
 48	struct page *page;
 49
 50	empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, 0);
 51	if (!empty_zero_page)
 52		panic("Oh boy, that early out of memory?");
 53
 54	page = virt_to_page((void *) empty_zero_page);
 55	SetPageReserved(page);
 56
 57	return 1UL;
 58}
 59
 60#ifndef CONFIG_NEED_MULTIPLE_NODES
 61int page_is_ram(unsigned long pagenr)
 62{
 63	if (pagenr >= min_low_pfn && pagenr < max_low_pfn)
 64		return 1;
 65	else
 66		return 0;
 67}
 68
 69void __init paging_init(void)
 70{
 71	unsigned long max_zone_pfns[MAX_NR_ZONES];
 72	unsigned long lastpfn;
 73
 74	pagetable_init();
 75	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
 76	lastpfn = max_low_pfn;
 77	free_area_init_nodes(max_zone_pfns);
 78}
 79
 80void __init mem_init(void)
 81{
 82	unsigned long codesize, reservedpages, datasize, initsize;
 83	unsigned long tmp, ram = 0;
 84
 85	high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
 86	totalram_pages += free_all_bootmem();
 87	totalram_pages -= setup_zero_page();	/* Setup zeroed pages. */
 88	reservedpages = 0;
 89
 90	for (tmp = 0; tmp < max_low_pfn; tmp++)
 91		if (page_is_ram(tmp)) {
 92			ram++;
 93			if (PageReserved(pfn_to_page(tmp)))
 94				reservedpages++;
 95		}
 96
 97	num_physpages = ram;
 98	codesize = (unsigned long) &_etext - (unsigned long) &_text;
 99	datasize = (unsigned long) &_edata - (unsigned long) &_etext;
100	initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
101
102	printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
103			"%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
104			(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
105			ram << (PAGE_SHIFT-10), codesize >> 10,
106			reservedpages << (PAGE_SHIFT-10), datasize >> 10,
107			initsize >> 10,
108			totalhigh_pages << (PAGE_SHIFT-10));
109}
110#endif /* !CONFIG_NEED_MULTIPLE_NODES */
111
112static void free_init_pages(const char *what, unsigned long begin, unsigned long end)
113{
114	unsigned long pfn;
115
116	for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
117		struct page *page = pfn_to_page(pfn);
118		void *addr = phys_to_virt(PFN_PHYS(pfn));
119
120		ClearPageReserved(page);
121		init_page_count(page);
122		memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
123		__free_page(page);
124		totalram_pages++;
125	}
126	printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
127}
128
129#ifdef CONFIG_BLK_DEV_INITRD
130void free_initrd_mem(unsigned long start, unsigned long end)
131{
132	free_init_pages("initrd memory",
133		virt_to_phys((void *) start),
134		virt_to_phys((void *) end));
135}
136#endif
137
138void __init_refok free_initmem(void)
139{
140	free_init_pages("unused kernel memory",
141	__pa(&__init_begin),
142	__pa(&__init_end));
143}
144
145unsigned long pgd_current;
146
147#define __page_aligned(order) __attribute__((__aligned__(PAGE_SIZE<<order)))
148
149/*
150 * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER
151 * are constants.  So we use the variants from asm-offset.h until that gcc
152 * will officially be retired.
153 */
154pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned(PTE_ORDER);
155pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER);