init.c

  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_or_panic(PAGE_SIZE, PAGE_SIZE);
 72	max_zone_pfn[ZONE_DMA] = end_mem >> PAGE_SHIFT;
 73	free_area_init(max_zone_pfn);
 74}
 75
 76#endif /* CONFIG_MMU */
 77
 78void free_initmem(void)
 79{
 80#ifndef CONFIG_MMU_SUN3
 81	free_initmem_default(-1);
 82#endif /* CONFIG_MMU_SUN3 */
 83}
 84
 85#if defined(CONFIG_MMU) && !defined(CONFIG_COLDFIRE)
 86#define VECTORS	&vectors[0]
 87#else
 88#define VECTORS	_ramvec
 89#endif
 90
 91static inline void init_pointer_tables(void)
 92{
 93#if defined(CONFIG_MMU) && !defined(CONFIG_SUN3) && !defined(CONFIG_COLDFIRE)
 94	int i, j;
 95
 96	/* insert pointer tables allocated so far into the tablelist */
 97	init_pointer_table(kernel_pg_dir, TABLE_PGD);
 98	for (i = 0; i < PTRS_PER_PGD; i++) {
 99		pud_t *pud = (pud_t *)&kernel_pg_dir[i];
100		pmd_t *pmd_dir;
101
102		if (!pud_present(*pud))
103			continue;
104
105		pmd_dir = (pmd_t *)pgd_page_vaddr(kernel_pg_dir[i]);
106		init_pointer_table(pmd_dir, TABLE_PMD);
107
108		for (j = 0; j < PTRS_PER_PMD; j++) {
109			pmd_t *pmd = &pmd_dir[j];
110			pte_t *pte_dir;
111
112			if (!pmd_present(*pmd))
113				continue;
114
115			pte_dir = (pte_t *)pmd_page_vaddr(*pmd);
116			init_pointer_table(pte_dir, TABLE_PTE);
117		}
118	}
119#endif
120}
121
122void __init mem_init(void)
123{
124	init_pointer_tables();
125}