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/system.h>
25#include <asm/machdep.h>
26#include <asm/io.h>
27
28extern void mmu_emu_init (unsigned long bootmem_end);
29
30const char bad_pmd_string[] = "Bad pmd in pte_alloc: %08lx\n";
31
32extern unsigned long num_pages;
33
34void free_initmem(void)
35{
36}
37
38/* For the sun3 we try to follow the i386 paging_init() more closely */
39/* start_mem and end_mem have PAGE_OFFSET added already */
40/* now sets up tables using sun3 PTEs rather than i386 as before. --m */
41void __init paging_init(void)
42{
43	pgd_t * pg_dir;
44	pte_t * pg_table;
45	int i;
46	unsigned long address;
47	unsigned long next_pgtable;
48	unsigned long bootmem_end;
49	unsigned long zones_size[MAX_NR_ZONES] = { 0, };
50	unsigned long size;
51
52#ifdef TEST_VERIFY_AREA
53	wp_works_ok = 0;
54#endif
55	empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
56	memset(empty_zero_page, 0, PAGE_SIZE);
57
58	address = PAGE_OFFSET;
59	pg_dir = swapper_pg_dir;
60	memset (swapper_pg_dir, 0, sizeof (swapper_pg_dir));
61	memset (kernel_pg_dir,  0, sizeof (kernel_pg_dir));
62
63	size = num_pages * sizeof(pte_t);
64	size = (size + PAGE_SIZE) & ~(PAGE_SIZE-1);
65
66	next_pgtable = (unsigned long)alloc_bootmem_pages(size);
67	bootmem_end = (next_pgtable + size + PAGE_SIZE) & PAGE_MASK;
68
69	/* Map whole memory from PAGE_OFFSET (0x0E000000) */
70	pg_dir += PAGE_OFFSET >> PGDIR_SHIFT;
71
72	while (address < (unsigned long)high_memory) {
73		pg_table = (pte_t *) __pa (next_pgtable);
74		next_pgtable += PTRS_PER_PTE * sizeof (pte_t);
75		pgd_val(*pg_dir) = (unsigned long) pg_table;
76		pg_dir++;
77
78		/* now change pg_table to kernel virtual addresses */
79		pg_table = (pte_t *) __va ((unsigned long) pg_table);
80		for (i=0; i<PTRS_PER_PTE; ++i, ++pg_table) {
81			pte_t pte = pfn_pte(virt_to_pfn(address), PAGE_INIT);
82			if (address >= (unsigned long)high_memory)
83				pte_val (pte) = 0;
84			set_pte (pg_table, pte);
85			address += PAGE_SIZE;
86		}
87	}
88
89	mmu_emu_init(bootmem_end);
90
91	current->mm = NULL;
92
93	/* memory sizing is a hack stolen from motorola.c..  hope it works for us */
94	zones_size[ZONE_DMA] = ((unsigned long)high_memory - PAGE_OFFSET) >> PAGE_SHIFT;
95
96	/* I really wish I knew why the following change made things better...  -- Sam */
97/*	free_area_init(zones_size); */
98	free_area_init_node(0, NODE_DATA(0), zones_size,
99			    (__pa(PAGE_OFFSET) >> PAGE_SHIFT) + 1, NULL);
100
101
102}
103