1 /* MN10300 Memory management initialisation
2 *
3 * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5 * Modified by David Howells (dhowells@redhat.com)
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public Licence
9 * as published by the Free Software Foundation; either version
10 * 2 of the Licence, or (at your option) any later version.
11 */
12 #include <linux/signal.h>
13 #include <linux/sched.h>
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/string.h>
17 #include <linux/types.h>
18 #include <linux/ptrace.h>
19 #include <linux/mman.h>
20 #include <linux/fs.h>
21 #include <linux/mm.h>
22 #include <linux/swap.h>
23 #include <linux/smp.h>
24 #include <linux/init.h>
25 #include <linux/initrd.h>
26 #include <linux/highmem.h>
27 #include <linux/pagemap.h>
28 #include <linux/bootmem.h>
29 #include <linux/gfp.h>
30
31 #include <asm/processor.h>
32 #include <asm/system.h>
33 #include <asm/uaccess.h>
34 #include <asm/pgtable.h>
35 #include <asm/pgalloc.h>
36 #include <asm/dma.h>
37 #include <asm/tlb.h>
38 #include <asm/sections.h>
39
40 unsigned long highstart_pfn, highend_pfn;
41
42 #ifdef CONFIG_MN10300_HAS_ATOMIC_OPS_UNIT
43 static struct vm_struct user_iomap_vm;
44 #endif
45
46 /*
47 * set up paging
48 */
paging_init(void)49 void __init paging_init(void)
50 {
51 unsigned long zones_size[MAX_NR_ZONES] = {0,};
52 pte_t *ppte;
53 int loop;
54
55 /* main kernel space -> RAM mapping is handled as 1:1 transparent by
56 * the MMU */
57 memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
58 memset(kernel_vmalloc_ptes, 0, sizeof(kernel_vmalloc_ptes));
59
60 /* load the VMALLOC area PTE table addresses into the kernel PGD */
61 ppte = kernel_vmalloc_ptes;
62 for (loop = VMALLOC_START / (PAGE_SIZE * PTRS_PER_PTE);
63 loop < VMALLOC_END / (PAGE_SIZE * PTRS_PER_PTE);
64 loop++
65 ) {
66 set_pgd(swapper_pg_dir + loop, __pgd(__pa(ppte) | _PAGE_TABLE));
67 ppte += PAGE_SIZE / sizeof(pte_t);
68 }
69
70 /* declare the sizes of the RAM zones (only use the normal zone) */
71 zones_size[ZONE_NORMAL] =
72 contig_page_data.bdata->node_low_pfn -
73 contig_page_data.bdata->node_min_pfn;
74
75 /* pass the memory from the bootmem allocator to the main allocator */
76 free_area_init(zones_size);
77
78 #ifdef CONFIG_MN10300_HAS_ATOMIC_OPS_UNIT
79 /* The Atomic Operation Unit registers need to be mapped to userspace
80 * for all processes. The following uses vm_area_register_early() to
81 * reserve the first page of the vmalloc area and sets the pte for that
82 * page.
83 *
84 * glibc hardcodes this virtual mapping, so we're pretty much stuck with
85 * it from now on.
86 */
87 user_iomap_vm.flags = VM_USERMAP;
88 user_iomap_vm.size = 1 << PAGE_SHIFT;
89 vm_area_register_early(&user_iomap_vm, PAGE_SIZE);
90 ppte = kernel_vmalloc_ptes;
91 set_pte(ppte, pfn_pte(USER_ATOMIC_OPS_PAGE_ADDR >> PAGE_SHIFT,
92 PAGE_USERIO));
93 #endif
94
95 local_flush_tlb_all();
96 }
97
98 /*
99 * transfer all the memory from the bootmem allocator to the runtime allocator
100 */
mem_init(void)101 void __init mem_init(void)
102 {
103 int codesize, reservedpages, datasize, initsize;
104 int tmp;
105
106 BUG_ON(!mem_map);
107
108 #define START_PFN (contig_page_data.bdata->node_min_pfn)
109 #define MAX_LOW_PFN (contig_page_data.bdata->node_low_pfn)
110
111 max_mapnr = num_physpages = MAX_LOW_PFN - START_PFN;
112 high_memory = (void *) __va(MAX_LOW_PFN * PAGE_SIZE);
113
114 /* clear the zero-page */
115 memset(empty_zero_page, 0, PAGE_SIZE);
116
117 /* this will put all low memory onto the freelists */
118 totalram_pages += free_all_bootmem();
119
120 reservedpages = 0;
121 for (tmp = 0; tmp < num_physpages; tmp++)
122 if (PageReserved(&mem_map[tmp]))
123 reservedpages++;
124
125 codesize = (unsigned long) &_etext - (unsigned long) &_stext;
126 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
127 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
128
129 printk(KERN_INFO
130 "Memory: %luk/%luk available"
131 " (%dk kernel code, %dk reserved, %dk data, %dk init,"
132 " %ldk highmem)\n",
133 nr_free_pages() << (PAGE_SHIFT - 10),
134 max_mapnr << (PAGE_SHIFT - 10),
135 codesize >> 10,
136 reservedpages << (PAGE_SHIFT - 10),
137 datasize >> 10,
138 initsize >> 10,
139 totalhigh_pages << (PAGE_SHIFT - 10));
140 }
141
142 /*
143 *
144 */
free_init_pages(char * what,unsigned long begin,unsigned long end)145 void free_init_pages(char *what, unsigned long begin, unsigned long end)
146 {
147 unsigned long addr;
148
149 for (addr = begin; addr < end; addr += PAGE_SIZE) {
150 ClearPageReserved(virt_to_page(addr));
151 init_page_count(virt_to_page(addr));
152 memset((void *) addr, 0xcc, PAGE_SIZE);
153 free_page(addr);
154 totalram_pages++;
155 }
156 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
157 }
158
159 /*
160 * recycle memory containing stuff only required for initialisation
161 */
free_initmem(void)162 void free_initmem(void)
163 {
164 free_init_pages("unused kernel memory",
165 (unsigned long) &__init_begin,
166 (unsigned long) &__init_end);
167 }
168
169 /*
170 * dispose of the memory on which the initial ramdisk resided
171 */
172 #ifdef CONFIG_BLK_DEV_INITRD
free_initrd_mem(unsigned long start,unsigned long end)173 void free_initrd_mem(unsigned long start, unsigned long end)
174 {
175 free_init_pages("initrd memory", start, end);
176 }
177 #endif
178