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/arch/mn10300/mm/init.c

http://github.com/mirrors/linux
C | 136 lines | 80 code | 18 blank | 38 comment | 1 complexity | d7460523197b7f954727cd14938b68a5 MD5 | raw file
  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/fs.h>
 21#include <linux/mm.h>
 22#include <linux/swap.h>
 23#include <linux/smp.h>
 24#include <linux/init.h>
 25#include <linux/initrd.h>
 26#include <linux/highmem.h>
 27#include <linux/pagemap.h>
 28#include <linux/bootmem.h>
 29#include <linux/gfp.h>
 30
 31#include <asm/processor.h>
 32#include <asm/uaccess.h>
 33#include <asm/pgtable.h>
 34#include <asm/pgalloc.h>
 35#include <asm/dma.h>
 36#include <asm/tlb.h>
 37#include <asm/sections.h>
 38
 39unsigned long highstart_pfn, highend_pfn;
 40
 41#ifdef CONFIG_MN10300_HAS_ATOMIC_OPS_UNIT
 42static struct vm_struct user_iomap_vm;
 43#endif
 44
 45/*
 46 * set up paging
 47 */
 48void __init paging_init(void)
 49{
 50	unsigned long zones_size[MAX_NR_ZONES] = {0,};
 51	pte_t *ppte;
 52	int loop;
 53
 54	/* main kernel space -> RAM mapping is handled as 1:1 transparent by
 55	 * the MMU */
 56	memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
 57	memset(kernel_vmalloc_ptes, 0, sizeof(kernel_vmalloc_ptes));
 58
 59	/* load the VMALLOC area PTE table addresses into the kernel PGD */
 60	ppte = kernel_vmalloc_ptes;
 61	for (loop = VMALLOC_START / (PAGE_SIZE * PTRS_PER_PTE);
 62	     loop < VMALLOC_END / (PAGE_SIZE * PTRS_PER_PTE);
 63	     loop++
 64	     ) {
 65		set_pgd(swapper_pg_dir + loop, __pgd(__pa(ppte) | _PAGE_TABLE));
 66		ppte += PAGE_SIZE / sizeof(pte_t);
 67	}
 68
 69	/* declare the sizes of the RAM zones (only use the normal zone) */
 70	zones_size[ZONE_NORMAL] =
 71		contig_page_data.bdata->node_low_pfn -
 72		contig_page_data.bdata->node_min_pfn;
 73
 74	/* pass the memory from the bootmem allocator to the main allocator */
 75	free_area_init(zones_size);
 76
 77#ifdef CONFIG_MN10300_HAS_ATOMIC_OPS_UNIT
 78	/* The Atomic Operation Unit registers need to be mapped to userspace
 79	 * for all processes.  The following uses vm_area_register_early() to
 80	 * reserve the first page of the vmalloc area and sets the pte for that
 81	 * page.
 82	 *
 83	 * glibc hardcodes this virtual mapping, so we're pretty much stuck with
 84	 * it from now on.
 85	 */
 86	user_iomap_vm.flags = VM_USERMAP;
 87	user_iomap_vm.size = 1 << PAGE_SHIFT;
 88	vm_area_register_early(&user_iomap_vm, PAGE_SIZE);
 89	ppte = kernel_vmalloc_ptes;
 90	set_pte(ppte, pfn_pte(USER_ATOMIC_OPS_PAGE_ADDR >> PAGE_SHIFT,
 91			      PAGE_USERIO));
 92#endif
 93
 94	local_flush_tlb_all();
 95}
 96
 97/*
 98 * transfer all the memory from the bootmem allocator to the runtime allocator
 99 */
100void __init mem_init(void)
101{
102	BUG_ON(!mem_map);
103
104#define START_PFN	(contig_page_data.bdata->node_min_pfn)
105#define MAX_LOW_PFN	(contig_page_data.bdata->node_low_pfn)
106
107	max_mapnr = MAX_LOW_PFN - START_PFN;
108	high_memory = (void *) __va(MAX_LOW_PFN * PAGE_SIZE);
109
110	/* clear the zero-page */
111	memset(empty_zero_page, 0, PAGE_SIZE);
112
113	/* this will put all low memory onto the freelists */
114	free_all_bootmem();
115
116	mem_init_print_info(NULL);
117}
118
119/*
120 * recycle memory containing stuff only required for initialisation
121 */
122void free_initmem(void)
123{
124	free_initmem_default(POISON_FREE_INITMEM);
125}
126
127/*
128 * dispose of the memory on which the initial ramdisk resided
129 */
130#ifdef CONFIG_BLK_DEV_INITRD
131void free_initrd_mem(unsigned long start, unsigned long end)
132{
133	free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
134			   "initrd");
135}
136#endif