| /* 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 low memory onto the freelists */ |
| 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--) |
| free_highmem_page(&mem_map[pfn]); |
| #endif |
| |
| codek = ((unsigned long) &_etext - (unsigned long) &_stext) >> 10; |
| datak = datapages << (PAGE_SHIFT - 10); |
| |
| #else |
| codek = (_etext - _stext) >> 10; |
| datak = 0; //(__bss_stop - _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) |
| free_initmem_default(0); |
| #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) |
| { |
| free_reserved_area(start, end, 0, "initrd"); |
| } /* end free_initrd_mem() */ |
| #endif |