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/bootmem.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 * BAD_PAGE is the page that is used for page faults when linux
44 * is out-of-memory. Older versions of linux just did a
45 * do_exit(), but using this instead means there is less risk
46 * for a process dying in kernel mode, possibly leaving a inode
47 * unused etc..
48 *
49 * BAD_PAGETABLE is the accompanying page-table: it is initialized
50 * to point to BAD_PAGE entries.
51 *
52 * ZERO_PAGE is a special page that is used for zero-initialized
53 * data and COW.
54 */
55 static unsigned long empty_bad_page_table;
56 static unsigned long empty_bad_page;
57 unsigned long empty_zero_page;
58
59 /*
60 * paging_init() continues the virtual memory environment setup which
61 * was begun by the code in arch/head.S.
62 * The parameters are pointers to where to stick the starting and ending
63 * addresses of available kernel virtual memory.
64 */
paging_init(void)65 void __init paging_init(void)
66 {
67 /*
68 * Make sure start_mem is page aligned, otherwise bootmem and
69 * page_alloc get different views og the world.
70 */
71 unsigned long start_mem = PAGE_ALIGN(memory_start);
72 unsigned long end_mem = memory_end & PAGE_MASK;
73
74 pr_debug("start_mem is %#lx\nvirtual_end is %#lx\n",
75 start_mem, end_mem);
76
77 /*
78 * Initialize the bad page table and bad page to point
79 * to a couple of allocated pages.
80 */
81 empty_bad_page_table = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
82 empty_bad_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
83 empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
84 memset((void *)empty_zero_page, 0, PAGE_SIZE);
85
86 /*
87 * Set up SFC/DFC registers (user data space).
88 */
89 set_fs(USER_DS);
90
91 pr_debug("before free_area_init\n");
92
93 pr_debug("free_area_init -> start_mem is %#lx\nvirtual_end is %#lx\n",
94 start_mem, end_mem);
95
96 {
97 unsigned long zones_size[MAX_NR_ZONES] = {0, };
98
99 zones_size[ZONE_NORMAL] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT;
100 free_area_init(zones_size);
101 }
102 }
103
mem_init(void)104 void __init mem_init(void)
105 {
106 pr_devel("Mem_init: start=%lx, end=%lx\n", memory_start, memory_end);
107
108 high_memory = (void *) (memory_end & PAGE_MASK);
109 max_mapnr = MAP_NR(high_memory);
110
111 /* this will put all low memory onto the freelists */
112 free_all_bootmem();
113
114 mem_init_print_info(NULL);
115 }
116
117
118 #ifdef CONFIG_BLK_DEV_INITRD
free_initrd_mem(unsigned long start,unsigned long end)119 void free_initrd_mem(unsigned long start, unsigned long end)
120 {
121 free_reserved_area((void *)start, (void *)end, -1, "initrd");
122 }
123 #endif
124
125 void
free_initmem(void)126 free_initmem(void)
127 {
128 free_initmem_default(-1);
129 }
130