arch/m68k/mm/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  */
  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 #ifdef CONFIG_DISCONTIGMEM
  48 pg_data_t pg_data_map[MAX_NUMNODES];
  49 EXPORT_SYMBOL(pg_data_map);
  50
  51 pg_data_t *pg_data_table[65];
  52 EXPORT_SYMBOL(pg_data_table);
  53 #endif
  54
  55 void __init m68k_setup_node(int node)
  56 {
  57 #ifdef CONFIG_DISCONTIGMEM
  58         struct m68k_mem_info *info = m68k_memory + node;
  59         int i, end;
  60
  61         i = (unsigned long)phys_to_virt(info->addr) >> __virt_to_node_shift();
  62         end = (unsigned long)phys_to_virt(info->addr + info->size - 1) >> __virt_to_node_shift();
  63         for (; i <= end; i++) {
  64                 if (pg_data_table[i])
  65                         pr_warn("overlap at %u for chunk %u\n", i, node);
  66                 pg_data_table[i] = pg_data_map + node;
  67         }
  68 #endif
  69         node_set_online(node);
  70 }
  71
  72 #else /* CONFIG_MMU */
  73
  74 /*
  75  * paging_init() continues the virtual memory environment setup which
  76  * was begun by the code in arch/head.S.
  77  * The parameters are pointers to where to stick the starting and ending
  78  * addresses of available kernel virtual memory.
  79  */
  80 void __init paging_init(void)
  81 {
  82         /*
  83          * Make sure start_mem is page aligned, otherwise bootmem and
  84          * page_alloc get different views of the world.
  85          */
  86         unsigned long end_mem = memory_end & PAGE_MASK;
  87         unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, };
  88
  89         high_memory = (void *) end_mem;
  90
  91         empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
  92         if (!empty_zero_page)
  93                 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
  94                       __func__, PAGE_SIZE, PAGE_SIZE);
  95
  96         /*
  97          * Set up SFC/DFC registers (user data space).
  98          */
  99         set_fs (USER_DS);
 100
 101         max_zone_pfn[ZONE_DMA] = end_mem >> PAGE_SHIFT;
 102         free_area_init(max_zone_pfn);
 103 }
 104
 105 #endif /* CONFIG_MMU */
 106
 107 void free_initmem(void)
 108 {
 109 #ifndef CONFIG_MMU_SUN3
 110         free_initmem_default(-1);
 111 #endif /* CONFIG_MMU_SUN3 */
 112 }
 113
 114 #if defined(CONFIG_MMU) && !defined(CONFIG_COLDFIRE)
 115 #define VECTORS &vectors[0]
 116 #else
 117 #define VECTORS _ramvec
 118 #endif
 119
 120 static inline void init_pointer_tables(void)
 121 {
 122 #if defined(CONFIG_MMU) && !defined(CONFIG_SUN3) && !defined(CONFIG_COLDFIRE)
 123         int i, j;
 124
 125         /* insert pointer tables allocated so far into the tablelist */
 126         init_pointer_table(kernel_pg_dir, TABLE_PGD);
 127         for (i = 0; i < PTRS_PER_PGD; i++) {
 128                 pud_t *pud = (pud_t *)&kernel_pg_dir[i];
 129                 pmd_t *pmd_dir;
 130
 131                 if (!pud_present(*pud))
 132                         continue;
 133
 134                 pmd_dir = (pmd_t *)pgd_page_vaddr(kernel_pg_dir[i]);
 135                 init_pointer_table(pmd_dir, TABLE_PMD);
 136
 137                 for (j = 0; j < PTRS_PER_PMD; j++) {
 138                         pmd_t *pmd = &pmd_dir[j];
 139                         pte_t *pte_dir;
 140
 141                         if (!pmd_present(*pmd))
 142                                 continue;
 143
 144                         pte_dir = (pte_t *)pmd_page_vaddr(*pmd);
 145                         init_pointer_table(pte_dir, TABLE_PTE);
 146                 }
 147         }
 148 #endif
 149 }
 150
 151 void __init mem_init(void)
 152 {
 153         /* this will put all memory onto the freelists */
 154         memblock_free_all();
 155         init_pointer_tables();
 156         mem_init_print_info(NULL);
 157 }