| /* |
| * linux/arch/arm26/mm/init.c |
| * |
| * Copyright (C) 1995-2002 Russell King |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| #include <linux/signal.h> |
| #include <linux/sched.h> |
| #include <linux/kernel.h> |
| #include <linux/errno.h> |
| #include <linux/string.h> |
| #include <linux/types.h> |
| #include <linux/ptrace.h> |
| #include <linux/mman.h> |
| #include <linux/mm.h> |
| #include <linux/swap.h> |
| #include <linux/smp.h> |
| #include <linux/init.h> |
| #include <linux/initrd.h> |
| #include <linux/bootmem.h> |
| #include <linux/blkdev.h> |
| #include <linux/pfn.h> |
| |
| #include <asm/segment.h> |
| #include <asm/mach-types.h> |
| #include <asm/dma.h> |
| #include <asm/hardware.h> |
| #include <asm/setup.h> |
| #include <asm/tlb.h> |
| |
| #include <asm/map.h> |
| |
| |
| #define TABLE_SIZE PTRS_PER_PTE * sizeof(pte_t)) |
| |
| struct mmu_gather mmu_gathers[NR_CPUS]; |
| |
| extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; |
| extern char _stext, _text, _etext, _end, __init_begin, __init_end; |
| #ifdef CONFIG_XIP_KERNEL |
| extern char _endtext, _sdata; |
| #endif |
| extern unsigned long phys_initrd_start; |
| extern unsigned long phys_initrd_size; |
| |
| /* |
| * The sole use of this is to pass memory configuration |
| * data from paging_init to mem_init. |
| */ |
| static struct meminfo meminfo __initdata = { 0, }; |
| |
| /* |
| * empty_zero_page is a special page that is used for |
| * zero-initialized data and COW. |
| */ |
| struct page *empty_zero_page; |
| |
| void show_mem(void) |
| { |
| int free = 0, total = 0, reserved = 0; |
| int shared = 0, cached = 0, slab = 0; |
| struct page *page, *end; |
| |
| printk("Mem-info:\n"); |
| show_free_areas(); |
| printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10)); |
| |
| |
| page = NODE_MEM_MAP(0); |
| end = page + NODE_DATA(0)->node_spanned_pages; |
| |
| do { |
| total++; |
| if (PageReserved(page)) |
| reserved++; |
| else if (PageSwapCache(page)) |
| cached++; |
| else if (PageSlab(page)) |
| slab++; |
| else if (!page_count(page)) |
| free++; |
| else |
| shared += page_count(page) - 1; |
| page++; |
| } while (page < end); |
| |
| printk("%d pages of RAM\n", total); |
| printk("%d free pages\n", free); |
| printk("%d reserved pages\n", reserved); |
| printk("%d slab pages\n", slab); |
| printk("%d pages shared\n", shared); |
| printk("%d pages swap cached\n", cached); |
| } |
| |
| struct node_info { |
| unsigned int start; |
| unsigned int end; |
| int bootmap_pages; |
| }; |
| |
| /* |
| * FIXME: We really want to avoid allocating the bootmap bitmap |
| * over the top of the initrd. Hopefully, this is located towards |
| * the start of a bank, so if we allocate the bootmap bitmap at |
| * the end, we won't clash. |
| */ |
| static unsigned int __init |
| find_bootmap_pfn(struct meminfo *mi, unsigned int bootmap_pages) |
| { |
| unsigned int start_pfn, bootmap_pfn; |
| unsigned int start, end; |
| |
| start_pfn = PFN_UP((unsigned long)&_end); |
| bootmap_pfn = 0; |
| |
| /* ARM26 machines only have one node */ |
| if (mi->bank->node != 0) |
| BUG(); |
| |
| start = PFN_UP(mi->bank->start); |
| end = PFN_DOWN(mi->bank->size + mi->bank->start); |
| |
| if (start < start_pfn) |
| start = start_pfn; |
| |
| if (end <= start) |
| BUG(); |
| |
| if (end - start >= bootmap_pages) |
| bootmap_pfn = start; |
| else |
| BUG(); |
| |
| return bootmap_pfn; |
| } |
| |
| /* |
| * Scan the memory info structure and pull out: |
| * - the end of memory |
| * - the number of nodes |
| * - the pfn range of each node |
| * - the number of bootmem bitmap pages |
| */ |
| static void __init |
| find_memend_and_nodes(struct meminfo *mi, struct node_info *np) |
| { |
| unsigned int memend_pfn = 0; |
| |
| nodes_clear(node_online_map); |
| node_set_online(0); |
| |
| np->bootmap_pages = 0; |
| |
| if (mi->bank->size == 0) { |
| BUG(); |
| } |
| |
| /* |
| * Get the start and end pfns for this bank |
| */ |
| np->start = PFN_UP(mi->bank->start); |
| np->end = PFN_DOWN(mi->bank->start + mi->bank->size); |
| |
| if (memend_pfn < np->end) |
| memend_pfn = np->end; |
| |
| /* |
| * Calculate the number of pages we require to |
| * store the bootmem bitmaps. |
| */ |
| np->bootmap_pages = bootmem_bootmap_pages(np->end - np->start); |
| |
| /* |
| * This doesn't seem to be used by the Linux memory |
| * manager any more. If we can get rid of it, we |
| * also get rid of some of the stuff above as well. |
| */ |
| max_low_pfn = memend_pfn - PFN_DOWN(PHYS_OFFSET); |
| max_pfn = memend_pfn - PFN_DOWN(PHYS_OFFSET); |
| mi->end = memend_pfn << PAGE_SHIFT; |
| |
| } |
| |
| /* |
| * Initialise the bootmem allocator for all nodes. This is called |
| * early during the architecture specific initialisation. |
| */ |
| void __init bootmem_init(struct meminfo *mi) |
| { |
| struct node_info node_info; |
| unsigned int bootmap_pfn; |
| pg_data_t *pgdat = NODE_DATA(0); |
| |
| find_memend_and_nodes(mi, &node_info); |
| |
| bootmap_pfn = find_bootmap_pfn(mi, node_info.bootmap_pages); |
| |
| /* |
| * Note that node 0 must always have some pages. |
| */ |
| if (node_info.end == 0) |
| BUG(); |
| |
| /* |
| * Initialise the bootmem allocator. |
| */ |
| init_bootmem_node(pgdat, bootmap_pfn, node_info.start, node_info.end); |
| |
| /* |
| * Register all available RAM in this node with the bootmem allocator. |
| */ |
| free_bootmem_node(pgdat, mi->bank->start, mi->bank->size); |
| |
| /* |
| * Register the kernel text and data with bootmem. |
| * Note: with XIP we dont register .text since |
| * its in ROM. |
| */ |
| #ifdef CONFIG_XIP_KERNEL |
| reserve_bootmem_node(pgdat, __pa(&_sdata), &_end - &_sdata); |
| #else |
| reserve_bootmem_node(pgdat, __pa(&_stext), &_end - &_stext); |
| #endif |
| |
| /* |
| * And don't forget to reserve the allocator bitmap, |
| * which will be freed later. |
| */ |
| reserve_bootmem_node(pgdat, bootmap_pfn << PAGE_SHIFT, |
| node_info.bootmap_pages << PAGE_SHIFT); |
| |
| /* |
| * These should likewise go elsewhere. They pre-reserve |
| * the screen memory region at the start of main system |
| * memory. FIXME - screen RAM is not 512K! |
| */ |
| reserve_bootmem_node(pgdat, 0x02000000, 0x00080000); |
| |
| #ifdef CONFIG_BLK_DEV_INITRD |
| initrd_start = phys_initrd_start; |
| initrd_end = initrd_start + phys_initrd_size; |
| |
| /* Achimedes machines only have one node, so initrd is in node 0 */ |
| #ifdef CONFIG_XIP_KERNEL |
| /* Only reserve initrd space if it is in RAM */ |
| if(initrd_start && initrd_start < 0x03000000){ |
| #else |
| if(initrd_start){ |
| #endif |
| reserve_bootmem_node(pgdat, __pa(initrd_start), |
| initrd_end - initrd_start); |
| } |
| #endif /* CONFIG_BLK_DEV_INITRD */ |
| |
| |
| } |
| |
| /* |
| * paging_init() sets up the page tables, initialises the zone memory |
| * maps, and sets up the zero page, bad page and bad page tables. |
| */ |
| void __init paging_init(struct meminfo *mi) |
| { |
| void *zero_page; |
| unsigned long zone_size[MAX_NR_ZONES]; |
| unsigned long zhole_size[MAX_NR_ZONES]; |
| struct bootmem_data *bdata; |
| pg_data_t *pgdat; |
| int i; |
| |
| memcpy(&meminfo, mi, sizeof(meminfo)); |
| |
| /* |
| * allocate the zero page. Note that we count on this going ok. |
| */ |
| zero_page = alloc_bootmem_low_pages(PAGE_SIZE); |
| |
| /* |
| * initialise the page tables. |
| */ |
| memtable_init(mi); |
| flush_tlb_all(); |
| |
| /* |
| * initialise the zones in node 0 (archimedes have only 1 node) |
| */ |
| |
| for (i = 0; i < MAX_NR_ZONES; i++) { |
| zone_size[i] = 0; |
| zhole_size[i] = 0; |
| } |
| |
| pgdat = NODE_DATA(0); |
| bdata = pgdat->bdata; |
| zone_size[0] = bdata->node_low_pfn - |
| (bdata->node_boot_start >> PAGE_SHIFT); |
| if (!zone_size[0]) |
| BUG(); |
| pgdat->node_mem_map = NULL; |
| free_area_init_node(0, pgdat, zone_size, |
| bdata->node_boot_start >> PAGE_SHIFT, zhole_size); |
| |
| /* |
| * finish off the bad pages once |
| * the mem_map is initialised |
| */ |
| memzero(zero_page, PAGE_SIZE); |
| empty_zero_page = virt_to_page(zero_page); |
| } |
| |
| static inline void free_area(unsigned long addr, unsigned long end, char *s) |
| { |
| unsigned int size = (end - addr) >> 10; |
| |
| for (; addr < end; addr += PAGE_SIZE) { |
| struct page *page = virt_to_page(addr); |
| ClearPageReserved(page); |
| init_page_count(page); |
| free_page(addr); |
| totalram_pages++; |
| } |
| |
| if (size && s) |
| printk(KERN_INFO "Freeing %s memory: %dK\n", s, size); |
| } |
| |
| /* |
| * mem_init() marks the free areas in the mem_map and tells us how much |
| * memory is free. This is done after various parts of the system have |
| * claimed their memory after the kernel image. |
| */ |
| void __init mem_init(void) |
| { |
| unsigned int codepages, datapages, initpages; |
| pg_data_t *pgdat = NODE_DATA(0); |
| extern int sysctl_overcommit_memory; |
| |
| |
| /* Note: data pages includes BSS */ |
| #ifdef CONFIG_XIP_KERNEL |
| codepages = &_endtext - &_text; |
| datapages = &_end - &_sdata; |
| #else |
| codepages = &_etext - &_text; |
| datapages = &_end - &_etext; |
| #endif |
| initpages = &__init_end - &__init_begin; |
| |
| high_memory = (void *)__va(meminfo.end); |
| max_mapnr = virt_to_page(high_memory) - mem_map; |
| |
| /* this will put all unused low memory onto the freelists */ |
| if (pgdat->node_spanned_pages != 0) |
| totalram_pages += free_all_bootmem_node(pgdat); |
| |
| num_physpages = meminfo.bank[0].size >> PAGE_SHIFT; |
| |
| printk(KERN_INFO "Memory: %luMB total\n", num_physpages >> (20 - PAGE_SHIFT)); |
| printk(KERN_NOTICE "Memory: %luKB available (%dK code, " |
| "%dK data, %dK init)\n", |
| (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), |
| codepages >> 10, datapages >> 10, initpages >> 10); |
| |
| /* |
| * Turn on overcommit on tiny machines |
| */ |
| if (PAGE_SIZE >= 16384 && num_physpages <= 128) { |
| sysctl_overcommit_memory = OVERCOMMIT_ALWAYS; |
| printk("Turning on overcommit\n"); |
| } |
| } |
| |
| void free_initmem(void){ |
| #ifndef CONFIG_XIP_KERNEL |
| free_area((unsigned long)(&__init_begin), |
| (unsigned long)(&__init_end), |
| "init"); |
| #endif |
| } |
| |
| #ifdef CONFIG_BLK_DEV_INITRD |
| |
| static int keep_initrd; |
| |
| void free_initrd_mem(unsigned long start, unsigned long end) |
| { |
| #ifdef CONFIG_XIP_KERNEL |
| /* Only bin initrd if it is in RAM... */ |
| if(!keep_initrd && start < 0x03000000) |
| #else |
| if (!keep_initrd) |
| #endif |
| free_area(start, end, "initrd"); |
| } |
| |
| static int __init keepinitrd_setup(char *__unused) |
| { |
| keep_initrd = 1; |
| return 1; |
| } |
| |
| __setup("keepinitrd", keepinitrd_setup); |
| #endif |