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Diffstat (limited to 'arch/frv/mm/init.c')
| -rw-r--r-- | arch/frv/mm/init.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/arch/frv/mm/init.c b/arch/frv/mm/init.c new file mode 100644 index 00000000..a19effcc --- /dev/null +++ b/arch/frv/mm/init.c @@ -0,0 +1,206 @@ +/* init.c: memory initialisation for FRV + * + * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * Derived from: + * - linux/arch/m68knommu/mm/init.c + * - Copyright (C) 1998 D. Jeff Dionne <jeff@lineo.ca>, Kenneth Albanowski <kjahds@kjahds.com>, + * - Copyright (C) 2000 Lineo, Inc. (www.lineo.com) + * - linux/arch/m68k/mm/init.c + * - Copyright (C) 1995 Hamish Macdonald + */ + +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/pagemap.h> +#include <linux/gfp.h> +#include <linux/swap.h> +#include <linux/mm.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/types.h> +#include <linux/bootmem.h> +#include <linux/highmem.h> +#include <linux/module.h> + +#include <asm/setup.h> +#include <asm/segment.h> +#include <asm/page.h> +#include <asm/pgtable.h> +#include <asm/mmu_context.h> +#include <asm/virtconvert.h> +#include <asm/sections.h> +#include <asm/tlb.h> + +#undef DEBUG + +/* + * BAD_PAGE is the page that is used for page faults when linux + * is out-of-memory. Older versions of linux just did a + * do_exit(), but using this instead means there is less risk + * for a process dying in kernel mode, possibly leaving a inode + * unused etc.. + * + * BAD_PAGETABLE is the accompanying page-table: it is initialized + * to point to BAD_PAGE entries. + * + * ZERO_PAGE is a special page that is used for zero-initialized + * data and COW. + */ +static unsigned long empty_bad_page_table; +static unsigned long empty_bad_page; + +unsigned long empty_zero_page; +EXPORT_SYMBOL(empty_zero_page); + +/*****************************************************************************/ +/* + * paging_init() continues the virtual memory environment setup which + * was begun by the code in arch/head.S. + * The parameters are pointers to where to stick the starting and ending + * addresses of available kernel virtual memory. + */ +void __init paging_init(void) +{ + unsigned long zones_size[MAX_NR_ZONES] = {0, }; + + /* allocate some pages for kernel housekeeping tasks */ + empty_bad_page_table = (unsigned long) alloc_bootmem_pages(PAGE_SIZE); + empty_bad_page = (unsigned long) alloc_bootmem_pages(PAGE_SIZE); + empty_zero_page = (unsigned long) alloc_bootmem_pages(PAGE_SIZE); + + memset((void *) empty_zero_page, 0, PAGE_SIZE); + +#ifdef CONFIG_HIGHMEM + if (num_physpages - num_mappedpages) { + pgd_t *pge; + pud_t *pue; + pmd_t *pme; + + pkmap_page_table = alloc_bootmem_pages(PAGE_SIZE); + + pge = swapper_pg_dir + pgd_index_k(PKMAP_BASE); + pue = pud_offset(pge, PKMAP_BASE); + pme = pmd_offset(pue, PKMAP_BASE); + __set_pmd(pme, virt_to_phys(pkmap_page_table) | _PAGE_TABLE); + } +#endif + + /* distribute the allocatable pages across the various zones and pass them to the allocator + */ + zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn; +#ifdef CONFIG_HIGHMEM + zones_size[ZONE_HIGHMEM] = num_physpages - num_mappedpages; +#endif + + free_area_init(zones_size); + +#ifdef CONFIG_MMU + /* initialise init's MMU context */ + init_new_context(&init_task, &init_mm); +#endif + +} /* end paging_init() */ + +/*****************************************************************************/ +/* + * + */ +void __init mem_init(void) +{ + unsigned long npages = (memory_end - memory_start) >> PAGE_SHIFT; + unsigned long tmp; +#ifdef CONFIG_MMU + unsigned long loop, pfn; + int datapages = 0; +#endif + int codek = 0, datak = 0; + + /* this will put all memory onto the freelists */ + totalram_pages = free_all_bootmem(); + +#ifdef CONFIG_MMU + for (loop = 0 ; loop < npages ; loop++) + if (PageReserved(&mem_map[loop])) + datapages++; + +#ifdef CONFIG_HIGHMEM + for (pfn = num_physpages - 1; pfn >= num_mappedpages; pfn--) { + struct page *page = &mem_map[pfn]; + + ClearPageReserved(page); + init_page_count(page); + __free_page(page); + totalram_pages++; + } +#endif + + codek = ((unsigned long) &_etext - (unsigned long) &_stext) >> 10; + datak = datapages << (PAGE_SHIFT - 10); + +#else + codek = (_etext - _stext) >> 10; + datak = 0; //(_ebss - _sdata) >> 10; +#endif + + tmp = nr_free_pages() << PAGE_SHIFT; + printk("Memory available: %luKiB/%luKiB RAM, %luKiB/%luKiB ROM (%dKiB kernel code, %dKiB data)\n", + tmp >> 10, + npages << (PAGE_SHIFT - 10), + (rom_length > 0) ? ((rom_length >> 10) - codek) : 0, + rom_length >> 10, + codek, + datak + ); + +} /* end mem_init() */ + +/*****************************************************************************/ +/* + * free the memory that was only required for initialisation + */ +void free_initmem(void) +{ +#if defined(CONFIG_RAMKERNEL) && !defined(CONFIG_PROTECT_KERNEL) + unsigned long start, end, addr; + + start = PAGE_ALIGN((unsigned long) &__init_begin); /* round up */ + end = ((unsigned long) &__init_end) & PAGE_MASK; /* round down */ + + /* next to check that the page we free is not a partial page */ + for (addr = start; addr < end; addr += PAGE_SIZE) { + ClearPageReserved(virt_to_page(addr)); + init_page_count(virt_to_page(addr)); + free_page(addr); + totalram_pages++; + } + + printk("Freeing unused kernel memory: %ldKiB freed (0x%lx - 0x%lx)\n", + (end - start) >> 10, start, end); +#endif +} /* end free_initmem() */ + +/*****************************************************************************/ +/* + * free the initial ramdisk memory + */ +#ifdef CONFIG_BLK_DEV_INITRD +void __init free_initrd_mem(unsigned long start, unsigned long end) +{ + int pages = 0; + for (; start < end; start += PAGE_SIZE) { + ClearPageReserved(virt_to_page(start)); + init_page_count(virt_to_page(start)); + free_page(start); + totalram_pages++; + pages++; + } + printk("Freeing initrd memory: %dKiB freed\n", (pages * PAGE_SIZE) >> 10); +} /* end free_initrd_mem() */ +#endif |