1 /* init.c: memory initialisation for FRV
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
12 * - linux/arch/m68knommu/mm/init.c
13 * - Copyright (C) 1998 D. Jeff Dionne <jeff@lineo.ca>, Kenneth Albanowski <kjahds@kjahds.com>,
14 * - Copyright (C) 2000 Lineo, Inc. (www.lineo.com)
15 * - linux/arch/m68k/mm/init.c
16 * - Copyright (C) 1995 Hamish Macdonald
19 #include <linux/config.h>
20 #include <linux/signal.h>
21 #include <linux/sched.h>
22 #include <linux/pagemap.h>
23 #include <linux/swap.h>
25 #include <linux/kernel.h>
26 #include <linux/string.h>
27 #include <linux/types.h>
28 #include <linux/bootmem.h>
29 #include <linux/highmem.h>
31 #include <asm/setup.h>
32 #include <asm/segment.h>
34 #include <asm/pgtable.h>
35 #include <asm/system.h>
36 #include <asm/mmu_context.h>
37 #include <asm/virtconvert.h>
38 #include <asm/sections.h>
43 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
46 * BAD_PAGE is the page that is used for page faults when linux
47 * is out-of-memory. Older versions of linux just did a
48 * do_exit(), but using this instead means there is less risk
49 * for a process dying in kernel mode, possibly leaving a inode
52 * BAD_PAGETABLE is the accompanying page-table: it is initialized
53 * to point to BAD_PAGE entries.
55 * ZERO_PAGE is a special page that is used for zero-initialized
58 static unsigned long empty_bad_page_table;
59 static unsigned long empty_bad_page;
60 unsigned long empty_zero_page;
62 /*****************************************************************************/
69 int free = 0, total = 0, reserved = 0, shared = 0;
71 printk("\nMem-info:\n");
75 struct page *page = &mem_map[i];
78 if (PageReserved(page))
80 else if (!page_count(page))
83 shared += page_count(page) - 1;
86 printk("%d pages of RAM\n",total);
87 printk("%d free pages\n",free);
88 printk("%d reserved pages\n",reserved);
89 printk("%d pages shared\n",shared);
91 } /* end show_mem() */
93 /*****************************************************************************/
95 * paging_init() continues the virtual memory environment setup which
96 * was begun by the code in arch/head.S.
97 * The parameters are pointers to where to stick the starting and ending
98 * addresses of available kernel virtual memory.
100 void __init paging_init(void)
102 unsigned long zones_size[MAX_NR_ZONES] = {0, 0, 0};
104 /* allocate some pages for kernel housekeeping tasks */
105 empty_bad_page_table = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
106 empty_bad_page = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
107 empty_zero_page = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
109 memset((void *) empty_zero_page, 0, PAGE_SIZE);
112 if (num_physpages - num_mappedpages) {
117 pkmap_page_table = alloc_bootmem_pages(PAGE_SIZE);
119 memset(pkmap_page_table, 0, PAGE_SIZE);
121 pge = swapper_pg_dir + pgd_index_k(PKMAP_BASE);
122 pue = pud_offset(pge, PKMAP_BASE);
123 pme = pmd_offset(pue, PKMAP_BASE);
124 __set_pmd(pme, virt_to_phys(pkmap_page_table) | _PAGE_TABLE);
128 /* distribute the allocatable pages across the various zones and pass them to the allocator
130 zones_size[ZONE_DMA] = max_low_pfn - min_low_pfn;
131 zones_size[ZONE_NORMAL] = 0;
132 #ifdef CONFIG_HIGHMEM
133 zones_size[ZONE_HIGHMEM] = num_physpages - num_mappedpages;
136 free_area_init(zones_size);
139 /* initialise init's MMU context */
140 init_new_context(&init_task, &init_mm);
143 } /* end paging_init() */
145 /*****************************************************************************/
149 void __init mem_init(void)
151 unsigned long npages = (memory_end - memory_start) >> PAGE_SHIFT;
154 unsigned long loop, pfn;
157 int codek = 0, datak = 0;
159 /* this will put all memory onto the freelists */
160 totalram_pages = free_all_bootmem();
163 for (loop = 0 ; loop < npages ; loop++)
164 if (PageReserved(&mem_map[loop]))
167 #ifdef CONFIG_HIGHMEM
168 for (pfn = num_physpages - 1; pfn >= num_mappedpages; pfn--) {
169 struct page *page = &mem_map[pfn];
171 ClearPageReserved(page);
172 set_page_count(page, 1);
178 codek = ((unsigned long) &_etext - (unsigned long) &_stext) >> 10;
179 datak = datapages << (PAGE_SHIFT - 10);
182 codek = (_etext - _stext) >> 10;
183 datak = 0; //(_ebss - _sdata) >> 10;
186 tmp = nr_free_pages() << PAGE_SHIFT;
187 printk("Memory available: %luKiB/%luKiB RAM, %luKiB/%luKiB ROM (%dKiB kernel code, %dKiB data)\n",
189 npages << (PAGE_SHIFT - 10),
190 (rom_length > 0) ? ((rom_length >> 10) - codek) : 0,
196 } /* end mem_init() */
198 /*****************************************************************************/
200 * free the memory that was only required for initialisation
202 void __init free_initmem(void)
204 #if defined(CONFIG_RAMKERNEL) && !defined(CONFIG_PROTECT_KERNEL)
205 unsigned long start, end, addr;
207 start = PAGE_ALIGN((unsigned long) &__init_begin); /* round up */
208 end = ((unsigned long) &__init_end) & PAGE_MASK; /* round down */
210 /* next to check that the page we free is not a partial page */
211 for (addr = start; addr < end; addr += PAGE_SIZE) {
212 ClearPageReserved(virt_to_page(addr));
213 set_page_count(virt_to_page(addr), 1);
218 printk("Freeing unused kernel memory: %ldKiB freed (0x%lx - 0x%lx)\n",
219 (end - start) >> 10, start, end);
221 } /* end free_initmem() */
223 /*****************************************************************************/
225 * free the initial ramdisk memory
227 #ifdef CONFIG_BLK_DEV_INITRD
228 void __init free_initrd_mem(unsigned long start, unsigned long end)
231 for (; start < end; start += PAGE_SIZE) {
232 ClearPageReserved(virt_to_page(start));
233 set_page_count(virt_to_page(start), 1);
238 printk("Freeing initrd memory: %dKiB freed\n", (pages * PAGE_SIZE) >> 10);
239 } /* end free_initrd_mem() */