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/*
* Copyright (C) 2004-2006 Atmel Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/init.h>
#include <linux/mmzone.h>
#include <linux/module.h>
#include <linux/bootmem.h>
#include <linux/pagemap.h>
#include <linux/nodemask.h>
#include <asm/page.h>
#include <asm/mmu_context.h>
#include <asm/tlb.h>
#include <asm/io.h>
#include <asm/dma.h>
#include <asm/setup.h>
#include <asm/sections.h>
pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_data;
struct page *empty_zero_page;
EXPORT_SYMBOL(empty_zero_page);
/*
* Cache of MMU context last used.
*/
unsigned long mmu_context_cache = NO_CONTEXT;
/*
* paging_init() sets up the page tables
*
* This routine also unmaps the page at virtual kernel address 0, so
* that we can trap those pesky NULL-reference errors in the kernel.
*/
void __init paging_init(void)
{
extern unsigned long _evba;
void *zero_page;
int nid;
/*
* Make sure we can handle exceptions before enabling
* paging. Not that we should ever _get_ any exceptions this
* early, but you never know...
*/
printk("Exception vectors start at %p\n", &_evba);
sysreg_write(EVBA, (unsigned long)&_evba);
/*
* Since we are ready to handle exceptions now, we should let
* the CPU generate them...
*/
__asm__ __volatile__ ("csrf %0" : : "i"(SR_EM_BIT));
/*
* Allocate the zero page. The allocator will panic if it
* can't satisfy the request, so no need to check.
*/
zero_page = alloc_bootmem_low_pages_node(NODE_DATA(0),
PAGE_SIZE);
sysreg_write(PTBR, (unsigned long)swapper_pg_dir);
enable_mmu();
printk ("CPU: Paging enabled\n");
for_each_online_node(nid) {
pg_data_t *pgdat = NODE_DATA(nid);
unsigned long zones_size[MAX_NR_ZONES];
unsigned long low, start_pfn;
start_pfn = pgdat->bdata->node_min_pfn;
low = pgdat->bdata->node_low_pfn;
memset(zones_size, 0, sizeof(zones_size));
zones_size[ZONE_NORMAL] = low - start_pfn;
printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
nid, start_pfn, low);
free_area_init_node(nid, zones_size, start_pfn, NULL);
printk("Node %u: mem_map starts at %p\n",
pgdat->node_id, pgdat->node_mem_map);
}
mem_map = NODE_DATA(0)->node_mem_map;
empty_zero_page = virt_to_page(zero_page);
flush_dcache_page(empty_zero_page);
}
void __init mem_init(void)
{
pg_data_t *pgdat;
high_memory = NULL;
/* this will put all low memory onto the freelists */
for_each_online_pgdat(pgdat) {
void *node_high_memory;
if (pgdat->node_spanned_pages != 0)
free_all_bootmem_node(pgdat);
node_high_memory = (void *)((pgdat->node_start_pfn
+ pgdat->node_spanned_pages)
<< PAGE_SHIFT);
if (node_high_memory > high_memory)
high_memory = node_high_memory;
}
max_mapnr = MAP_NR(high_memory);
mem_init_print_info(NULL);
}
void free_initmem(void)
{
free_initmem_default(-1);
}
#ifdef CONFIG_BLK_DEV_INITRD
void free_initrd_mem(unsigned long start, unsigned long end)
{
free_reserved_area((void *)start, (void *)end, -1, "initrd");
}
#endif
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