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/sections.h>
40
41 /*
42 * ZERO_PAGE is a special page that is used for zero-initialized
43 * data and COW.
44 */
45 unsigned long empty_zero_page;
46
47 /*
48 * paging_init() continues the virtual memory environment setup which
49 * was begun by the code in arch/head.S.
50 * The parameters are pointers to where to stick the starting and ending
51 * addresses of available kernel virtual memory.
52 */
paging_init(void)53 void __init paging_init(void)
54 {
55 /*
56 * Make sure start_mem is page aligned, otherwise bootmem and
57 * page_alloc get different views og the world.
58 */
59 unsigned long start_mem = PAGE_ALIGN(memory_start);
60 unsigned long end_mem = memory_end & PAGE_MASK;
61
62 pr_debug("start_mem is %#lx\nvirtual_end is %#lx\n",
63 start_mem, end_mem);
64
65 /*
66 * Initialize the bad page table and bad page to point
67 * to a couple of allocated pages.
68 */
69 empty_zero_page = (unsigned long)memblock_alloc(PAGE_SIZE, PAGE_SIZE);
70 if (!empty_zero_page)
71 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
72 __func__, PAGE_SIZE, PAGE_SIZE);
73
74 /*
75 * Set up SFC/DFC registers (user data space).
76 */
77 set_fs(USER_DS);
78
79 pr_debug("before free_area_init\n");
80
81 pr_debug("free_area_init -> start_mem is %#lx\nvirtual_end is %#lx\n",
82 start_mem, end_mem);
83
84 {
85 unsigned long max_zone_pfn[MAX_NR_ZONES] = {0, };
86
87 max_zone_pfn[ZONE_NORMAL] = end_mem >> PAGE_SHIFT;
88 free_area_init(max_zone_pfn);
89 }
90 }
91
mem_init(void)92 void __init mem_init(void)
93 {
94 pr_devel("Mem_init: start=%lx, end=%lx\n", memory_start, memory_end);
95
96 high_memory = (void *) (memory_end & PAGE_MASK);
97 max_mapnr = MAP_NR(high_memory);
98
99 /* this will put all low memory onto the freelists */
100 memblock_free_all();
101 }
102