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 */ 40 void *empty_zero_page; 41 EXPORT_SYMBOL(empty_zero_page); 42 43 #ifdef CONFIG_MMU 44 45 int m68k_virt_to_node_shift; 46 47 void __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 */ 60 void __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 76 /* 77 * Set up SFC/DFC registers (user data space). 78 */ 79 set_fs (USER_DS); 80 81 max_zone_pfn[ZONE_DMA] = end_mem >> PAGE_SHIFT; 82 free_area_init(max_zone_pfn); 83 } 84 85 #endif /* CONFIG_MMU */ 86 87 void free_initmem(void) 88 { 89 #ifndef CONFIG_MMU_SUN3 90 free_initmem_default(-1); 91 #endif /* CONFIG_MMU_SUN3 */ 92 } 93 94 #if defined(CONFIG_MMU) && !defined(CONFIG_COLDFIRE) 95 #define VECTORS &vectors[0] 96 #else 97 #define VECTORS _ramvec 98 #endif 99 100 static inline void init_pointer_tables(void) 101 { 102 #if defined(CONFIG_MMU) && !defined(CONFIG_SUN3) && !defined(CONFIG_COLDFIRE) 103 int i, j; 104 105 /* insert pointer tables allocated so far into the tablelist */ 106 init_pointer_table(kernel_pg_dir, TABLE_PGD); 107 for (i = 0; i < PTRS_PER_PGD; i++) { 108 pud_t *pud = (pud_t *)&kernel_pg_dir[i]; 109 pmd_t *pmd_dir; 110 111 if (!pud_present(*pud)) 112 continue; 113 114 pmd_dir = (pmd_t *)pgd_page_vaddr(kernel_pg_dir[i]); 115 init_pointer_table(pmd_dir, TABLE_PMD); 116 117 for (j = 0; j < PTRS_PER_PMD; j++) { 118 pmd_t *pmd = &pmd_dir[j]; 119 pte_t *pte_dir; 120 121 if (!pmd_present(*pmd)) 122 continue; 123 124 pte_dir = (pte_t *)pmd_page_vaddr(*pmd); 125 init_pointer_table(pte_dir, TABLE_PTE); 126 } 127 } 128 #endif 129 } 130 131 void __init mem_init(void) 132 { 133 /* this will put all memory onto the freelists */ 134 memblock_free_all(); 135 init_pointer_tables(); 136 } 137