1// SPDX-License-Identifier: GPL-2.0
2/*
3 *  linux/arch/m68k/mm/init.c
4 *
5 *  Copyright (C) 1995  Hamish Macdonald
6 *
7 *  Contains common initialization routines, specific init code moved
8 *  to motorola.c and sun3mmu.c
9 */
10
11#include <linux/module.h>
12#include <linux/signal.h>
13#include <linux/sched.h>
14#include <linux/mm.h>
15#include <linux/swap.h>
16#include <linux/kernel.h>
17#include <linux/string.h>
18#include <linux/types.h>
19#include <linux/init.h>
20#include <linux/memblock.h>
21#include <linux/gfp.h>
22
23#include <asm/setup.h>
24#include <linux/uaccess.h>
25#include <asm/page.h>
26#include <asm/pgalloc.h>
27#include <asm/traps.h>
28#include <asm/machdep.h>
29#include <asm/io.h>
30#ifdef CONFIG_ATARI
31#include <asm/atari_stram.h>
32#endif
33#include <asm/sections.h>
34#include <asm/tlb.h>
35
36/*
37 * ZERO_PAGE is a special page that is used for zero-initialized
38 * data and COW.
39 */
40void *empty_zero_page;
41EXPORT_SYMBOL(empty_zero_page);
42
43#ifdef CONFIG_MMU
44
45int m68k_virt_to_node_shift;
46
47void __init m68k_setup_node(int node)
48{
49	node_set_online(node);
50}
51
52#else /* CONFIG_MMU */
53
54/*
55 * paging_init() continues the virtual memory environment setup which
56 * was begun by the code in arch/head.S.
57 * The parameters are pointers to where to stick the starting and ending
58 * addresses of available kernel virtual memory.
59 */
60void __init paging_init(void)
61{
62	/*
63	 * Make sure start_mem is page aligned, otherwise bootmem and
64	 * page_alloc get different views of the world.
65	 */
66	unsigned long end_mem = memory_end & PAGE_MASK;
67	unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, };
68
69	high_memory = (void *) end_mem;
70
71	empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
72	if (!empty_zero_page)
73		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
74		      __func__, PAGE_SIZE, PAGE_SIZE);
75	max_zone_pfn[ZONE_DMA] = end_mem >> PAGE_SHIFT;
76	free_area_init(max_zone_pfn);
77}
78
79#endif /* CONFIG_MMU */
80
81void free_initmem(void)
82{
83#ifndef CONFIG_MMU_SUN3
84	free_initmem_default(-1);
85#endif /* CONFIG_MMU_SUN3 */
86}
87
88#if defined(CONFIG_MMU) && !defined(CONFIG_COLDFIRE)
89#define VECTORS	&vectors[0]
90#else
91#define VECTORS	_ramvec
92#endif
93
94static inline void init_pointer_tables(void)
95{
96#if defined(CONFIG_MMU) && !defined(CONFIG_SUN3) && !defined(CONFIG_COLDFIRE)
97	int i, j;
98
99	/* insert pointer tables allocated so far into the tablelist */
100	init_pointer_table(kernel_pg_dir, TABLE_PGD);
101	for (i = 0; i < PTRS_PER_PGD; i++) {
102		pud_t *pud = (pud_t *)&kernel_pg_dir[i];
103		pmd_t *pmd_dir;
104
105		if (!pud_present(*pud))
106			continue;
107
108		pmd_dir = (pmd_t *)pgd_page_vaddr(kernel_pg_dir[i]);
109		init_pointer_table(pmd_dir, TABLE_PMD);
110
111		for (j = 0; j < PTRS_PER_PMD; j++) {
112			pmd_t *pmd = &pmd_dir[j];
113			pte_t *pte_dir;
114
115			if (!pmd_present(*pmd))
116				continue;
117
118			pte_dir = (pte_t *)pmd_page_vaddr(*pmd);
119			init_pointer_table(pte_dir, TABLE_PTE);
120		}
121	}
122#endif
123}
124
125void __init mem_init(void)
126{
127	/* this will put all memory onto the freelists */
128	memblock_free_all();
129	init_pointer_tables();
130}
131