xref: /kernel/linux/linux-5.10/arch/h8300/mm/init.c (revision 8c2ecf20) 
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 */
45unsigned 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 */
53void __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
92void __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	mem_init_print_info(NULL);
103}
104