1 /* 2 * linux/arch/m68k/mm/sun3mmu.c 3 * 4 * Implementations of mm routines specific to the sun3 MMU. 5 * 6 * Moved here 8/20/1999 Sam Creasey 7 * 8 */ 9 10 #include <linux/signal.h> 11 #include <linux/sched.h> 12 #include <linux/mm.h> 13 #include <linux/swap.h> 14 #include <linux/kernel.h> 15 #include <linux/string.h> 16 #include <linux/types.h> 17 #include <linux/init.h> 18 #include <linux/bootmem.h> 19 20 #include <asm/setup.h> 21 #include <asm/uaccess.h> 22 #include <asm/page.h> 23 #include <asm/pgtable.h> 24 #include <asm/machdep.h> 25 #include <asm/io.h> 26 27 extern void mmu_emu_init (unsigned long bootmem_end); 28 29 const char bad_pmd_string[] = "Bad pmd in pte_alloc: %08lx\n"; 30 31 extern unsigned long num_pages; 32 33 /* For the sun3 we try to follow the i386 paging_init() more closely */ 34 /* start_mem and end_mem have PAGE_OFFSET added already */ 35 /* now sets up tables using sun3 PTEs rather than i386 as before. --m */ 36 void __init paging_init(void) 37 { 38 pgd_t * pg_dir; 39 pte_t * pg_table; 40 int i; 41 unsigned long address; 42 unsigned long next_pgtable; 43 unsigned long bootmem_end; 44 unsigned long zones_size[MAX_NR_ZONES] = { 0, }; 45 unsigned long size; 46 47 #ifdef TEST_VERIFY_AREA 48 wp_works_ok = 0; 49 #endif 50 empty_zero_page = alloc_bootmem_pages(PAGE_SIZE); 51 52 address = PAGE_OFFSET; 53 pg_dir = swapper_pg_dir; 54 memset (swapper_pg_dir, 0, sizeof (swapper_pg_dir)); 55 memset (kernel_pg_dir, 0, sizeof (kernel_pg_dir)); 56 57 size = num_pages * sizeof(pte_t); 58 size = (size + PAGE_SIZE) & ~(PAGE_SIZE-1); 59 60 next_pgtable = (unsigned long)alloc_bootmem_pages(size); 61 bootmem_end = (next_pgtable + size + PAGE_SIZE) & PAGE_MASK; 62 63 /* Map whole memory from PAGE_OFFSET (0x0E000000) */ 64 pg_dir += PAGE_OFFSET >> PGDIR_SHIFT; 65 66 while (address < (unsigned long)high_memory) { 67 pg_table = (pte_t *) __pa (next_pgtable); 68 next_pgtable += PTRS_PER_PTE * sizeof (pte_t); 69 pgd_val(*pg_dir) = (unsigned long) pg_table; 70 pg_dir++; 71 72 /* now change pg_table to kernel virtual addresses */ 73 pg_table = (pte_t *) __va ((unsigned long) pg_table); 74 for (i=0; i<PTRS_PER_PTE; ++i, ++pg_table) { 75 pte_t pte = pfn_pte(virt_to_pfn(address), PAGE_INIT); 76 if (address >= (unsigned long)high_memory) 77 pte_val (pte) = 0; 78 set_pte (pg_table, pte); 79 address += PAGE_SIZE; 80 } 81 } 82 83 mmu_emu_init(bootmem_end); 84 85 current->mm = NULL; 86 87 /* memory sizing is a hack stolen from motorola.c.. hope it works for us */ 88 zones_size[ZONE_DMA] = ((unsigned long)high_memory - PAGE_OFFSET) >> PAGE_SHIFT; 89 90 /* I really wish I knew why the following change made things better... -- Sam */ 91 /* free_area_init(zones_size); */ 92 free_area_init_node(0, zones_size, 93 (__pa(PAGE_OFFSET) >> PAGE_SHIFT) + 1, NULL); 94 95 96 } 97 98 99