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 	mem_init_print_info(NULL);
103 }
104