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Linux kernel mirror (for testing)
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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/arch/h8300/mm/init.c
4 *
5 * Copyright (C) 1998 D. Jeff Dionne <jeff@lineo.ca>,
6 * Kenneth Albanowski <kjahds@kjahds.com>,
7 * Copyright (C) 2000 Lineo, Inc. (www.lineo.com)
8 *
9 * Based on:
10 *
11 * linux/arch/m68knommu/mm/init.c
12 * linux/arch/m68k/mm/init.c
13 *
14 * Copyright (C) 1995 Hamish Macdonald
15 *
16 * JAN/1999 -- hacked to support ColdFire (gerg@snapgear.com)
17 * DEC/2000 -- linux 2.4 support <davidm@snapgear.com>
18 */
19
20#include <linux/signal.h>
21#include <linux/sched.h>
22#include <linux/kernel.h>
23#include <linux/errno.h>
24#include <linux/string.h>
25#include <linux/types.h>
26#include <linux/ptrace.h>
27#include <linux/mman.h>
28#include <linux/mm.h>
29#include <linux/swap.h>
30#include <linux/init.h>
31#include <linux/highmem.h>
32#include <linux/pagemap.h>
33#include <linux/memblock.h>
34#include <linux/gfp.h>
35
36#include <asm/setup.h>
37#include <asm/segment.h>
38#include <asm/page.h>
39#include <asm/pgtable.h>
40#include <asm/sections.h>
41
42/*
43 * ZERO_PAGE is a special page that is used for zero-initialized
44 * data and COW.
45 */
46unsigned long empty_zero_page;
47
48/*
49 * paging_init() continues the virtual memory environment setup which
50 * was begun by the code in arch/head.S.
51 * The parameters are pointers to where to stick the starting and ending
52 * addresses of available kernel virtual memory.
53 */
54void __init paging_init(void)
55{
56 /*
57 * Make sure start_mem is page aligned, otherwise bootmem and
58 * page_alloc get different views og the world.
59 */
60 unsigned long start_mem = PAGE_ALIGN(memory_start);
61 unsigned long end_mem = memory_end & PAGE_MASK;
62
63 pr_debug("start_mem is %#lx\nvirtual_end is %#lx\n",
64 start_mem, end_mem);
65
66 /*
67 * Initialize the bad page table and bad page to point
68 * to a couple of allocated pages.
69 */
70 empty_zero_page = (unsigned long)memblock_alloc(PAGE_SIZE, PAGE_SIZE);
71 if (!empty_zero_page)
72 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
73 __func__, PAGE_SIZE, PAGE_SIZE);
74
75 /*
76 * Set up SFC/DFC registers (user data space).
77 */
78 set_fs(USER_DS);
79
80 pr_debug("before free_area_init\n");
81
82 pr_debug("free_area_init -> start_mem is %#lx\nvirtual_end is %#lx\n",
83 start_mem, end_mem);
84
85 {
86 unsigned long zones_size[MAX_NR_ZONES] = {0, };
87
88 zones_size[ZONE_NORMAL] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT;
89 free_area_init(zones_size);
90 }
91}
92
93void __init mem_init(void)
94{
95 pr_devel("Mem_init: start=%lx, end=%lx\n", memory_start, memory_end);
96
97 high_memory = (void *) (memory_end & PAGE_MASK);
98 max_mapnr = MAP_NR(high_memory);
99
100 /* this will put all low memory onto the freelists */
101 memblock_free_all();
102
103 mem_init_print_info(NULL);
104}