| /* $Id: init.c,v 1.19 2004/02/21 04:42:16 kkojima Exp $ |
| * |
| * linux/arch/sh/mm/init.c |
| * |
| * Copyright (C) 1999 Niibe Yutaka |
| * Copyright (C) 2002, 2004 Paul Mundt |
| * |
| * Based on linux/arch/i386/mm/init.c: |
| * Copyright (C) 1995 Linus Torvalds |
| */ |
| |
| #include <linux/config.h> |
| #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/highmem.h> |
| #include <linux/bootmem.h> |
| #include <linux/pagemap.h> |
| |
| #include <asm/processor.h> |
| #include <asm/system.h> |
| #include <asm/uaccess.h> |
| #include <asm/pgtable.h> |
| #include <asm/pgalloc.h> |
| #include <asm/mmu_context.h> |
| #include <asm/io.h> |
| #include <asm/tlb.h> |
| #include <asm/cacheflush.h> |
| #include <asm/cache.h> |
| |
| DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); |
| pgd_t swapper_pg_dir[PTRS_PER_PGD]; |
| |
| /* |
| * Cache of MMU context last used. |
| */ |
| unsigned long mmu_context_cache = NO_CONTEXT; |
| |
| #ifdef CONFIG_MMU |
| /* It'd be good if these lines were in the standard header file. */ |
| #define START_PFN (NODE_DATA(0)->bdata->node_boot_start >> PAGE_SHIFT) |
| #define MAX_LOW_PFN (NODE_DATA(0)->bdata->node_low_pfn) |
| #endif |
| |
| #ifdef CONFIG_DISCONTIGMEM |
| pg_data_t discontig_page_data[MAX_NUMNODES]; |
| bootmem_data_t discontig_node_bdata[MAX_NUMNODES]; |
| #endif |
| |
| void (*copy_page)(void *from, void *to); |
| void (*clear_page)(void *to); |
| |
| void show_mem(void) |
| { |
| int i, total = 0, reserved = 0; |
| int shared = 0, cached = 0; |
| |
| printk("Mem-info:\n"); |
| show_free_areas(); |
| printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10)); |
| i = max_mapnr; |
| while (i-- > 0) { |
| total++; |
| if (PageReserved(mem_map+i)) |
| reserved++; |
| else if (PageSwapCache(mem_map+i)) |
| cached++; |
| else if (page_count(mem_map+i)) |
| shared += page_count(mem_map+i) - 1; |
| } |
| printk("%d pages of RAM\n",total); |
| printk("%d reserved pages\n",reserved); |
| printk("%d pages shared\n",shared); |
| printk("%d pages swap cached\n",cached); |
| } |
| |
| static void set_pte_phys(unsigned long addr, unsigned long phys, pgprot_t prot) |
| { |
| pgd_t *pgd; |
| pmd_t *pmd; |
| pte_t *pte; |
| |
| pgd = swapper_pg_dir + pgd_index(addr); |
| if (pgd_none(*pgd)) { |
| pgd_ERROR(*pgd); |
| return; |
| } |
| |
| pmd = pmd_offset(pgd, addr); |
| if (pmd_none(*pmd)) { |
| pte = (pte_t *)get_zeroed_page(GFP_ATOMIC); |
| set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE | _PAGE_USER)); |
| if (pte != pte_offset_kernel(pmd, 0)) { |
| pmd_ERROR(*pmd); |
| return; |
| } |
| } |
| |
| pte = pte_offset_kernel(pmd, addr); |
| if (!pte_none(*pte)) { |
| pte_ERROR(*pte); |
| return; |
| } |
| |
| set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, prot)); |
| |
| __flush_tlb_page(get_asid(), addr); |
| } |
| |
| /* |
| * As a performance optimization, other platforms preserve the fixmap mapping |
| * across a context switch, we don't presently do this, but this could be done |
| * in a similar fashion as to the wired TLB interface that sh64 uses (by way |
| * of the memorry mapped UTLB configuration) -- this unfortunately forces us to |
| * give up a TLB entry for each mapping we want to preserve. While this may be |
| * viable for a small number of fixmaps, it's not particularly useful for |
| * everything and needs to be carefully evaluated. (ie, we may want this for |
| * the vsyscall page). |
| * |
| * XXX: Perhaps add a _PAGE_WIRED flag or something similar that we can pass |
| * in at __set_fixmap() time to determine the appropriate behavior to follow. |
| * |
| * -- PFM. |
| */ |
| void __set_fixmap(enum fixed_addresses idx, unsigned long phys, pgprot_t prot) |
| { |
| unsigned long address = __fix_to_virt(idx); |
| |
| if (idx >= __end_of_fixed_addresses) { |
| BUG(); |
| return; |
| } |
| |
| set_pte_phys(address, phys, prot); |
| } |
| |
| /* References to section boundaries */ |
| |
| extern char _text, _etext, _edata, __bss_start, _end; |
| extern char __init_begin, __init_end; |
| |
| /* |
| * paging_init() sets up the page tables |
| * |
| * This routines also unmaps the page at virtual kernel address 0, so |
| * that we can trap those pesky NULL-reference errors in the kernel. |
| */ |
| void __init paging_init(void) |
| { |
| unsigned long zones_size[MAX_NR_ZONES] = { 0, }; |
| |
| /* |
| * Setup some defaults for the zone sizes.. these should be safe |
| * regardless of distcontiguous memory or MMU settings. |
| */ |
| zones_size[ZONE_DMA] = 0 >> PAGE_SHIFT; |
| zones_size[ZONE_NORMAL] = __MEMORY_SIZE >> PAGE_SHIFT; |
| #ifdef CONFIG_HIGHMEM |
| zones_size[ZONE_HIGHMEM] = 0 >> PAGE_SHIFT; |
| #endif |
| |
| #ifdef CONFIG_MMU |
| /* |
| * If we have an MMU, and want to be using it .. we need to adjust |
| * the zone sizes accordingly, in addition to turning it on. |
| */ |
| { |
| unsigned long max_dma, low, start_pfn; |
| pgd_t *pg_dir; |
| int i; |
| |
| /* We don't need kernel mapping as hardware support that. */ |
| pg_dir = swapper_pg_dir; |
| |
| for (i = 0; i < PTRS_PER_PGD; i++) |
| pgd_val(pg_dir[i]) = 0; |
| |
| /* Turn on the MMU */ |
| enable_mmu(); |
| |
| /* Fixup the zone sizes */ |
| start_pfn = START_PFN; |
| max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT; |
| low = MAX_LOW_PFN; |
| |
| if (low < max_dma) { |
| zones_size[ZONE_DMA] = low - start_pfn; |
| zones_size[ZONE_NORMAL] = 0; |
| } else { |
| zones_size[ZONE_DMA] = max_dma - start_pfn; |
| zones_size[ZONE_NORMAL] = low - max_dma; |
| } |
| } |
| |
| #elif defined(CONFIG_CPU_SH3) || defined(CONFIG_CPU_SH4) |
| /* |
| * If we don't have CONFIG_MMU set and the processor in question |
| * still has an MMU, care needs to be taken to make sure it doesn't |
| * stay on.. Since the boot loader could have potentially already |
| * turned it on, and we clearly don't want it, we simply turn it off. |
| * |
| * We don't need to do anything special for the zone sizes, since the |
| * default values that were already configured up above should be |
| * satisfactory. |
| */ |
| disable_mmu(); |
| #endif |
| NODE_DATA(0)->node_mem_map = NULL; |
| free_area_init_node(0, NODE_DATA(0), zones_size, __MEMORY_START >> PAGE_SHIFT, 0); |
| |
| #ifdef CONFIG_DISCONTIGMEM |
| /* |
| * And for discontig, do some more fixups on the zone sizes.. |
| */ |
| zones_size[ZONE_DMA] = __MEMORY_SIZE_2ND >> PAGE_SHIFT; |
| zones_size[ZONE_NORMAL] = 0; |
| free_area_init_node(1, NODE_DATA(1), zones_size, __MEMORY_START_2ND >> PAGE_SHIFT, 0); |
| #endif |
| } |
| |
| void __init mem_init(void) |
| { |
| extern unsigned long empty_zero_page[1024]; |
| int codesize, reservedpages, datasize, initsize; |
| int tmp; |
| extern unsigned long memory_start; |
| |
| #ifdef CONFIG_MMU |
| high_memory = (void *)__va(MAX_LOW_PFN * PAGE_SIZE); |
| #else |
| extern unsigned long memory_end; |
| |
| high_memory = (void *)(memory_end & PAGE_MASK); |
| #endif |
| |
| max_mapnr = num_physpages = MAP_NR(high_memory) - MAP_NR(memory_start); |
| |
| /* clear the zero-page */ |
| memset(empty_zero_page, 0, PAGE_SIZE); |
| __flush_wback_region(empty_zero_page, PAGE_SIZE); |
| |
| /* |
| * Setup wrappers for copy/clear_page(), these will get overridden |
| * later in the boot process if a better method is available. |
| */ |
| copy_page = copy_page_slow; |
| clear_page = clear_page_slow; |
| |
| /* this will put all low memory onto the freelists */ |
| totalram_pages += free_all_bootmem_node(NODE_DATA(0)); |
| #ifdef CONFIG_DISCONTIGMEM |
| totalram_pages += free_all_bootmem_node(NODE_DATA(1)); |
| #endif |
| reservedpages = 0; |
| for (tmp = 0; tmp < num_physpages; tmp++) |
| /* |
| * Only count reserved RAM pages |
| */ |
| if (PageReserved(mem_map+tmp)) |
| reservedpages++; |
| |
| codesize = (unsigned long) &_etext - (unsigned long) &_text; |
| datasize = (unsigned long) &_edata - (unsigned long) &_etext; |
| initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; |
| |
| printk("Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init)\n", |
| (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), |
| max_mapnr << (PAGE_SHIFT-10), |
| codesize >> 10, |
| reservedpages << (PAGE_SHIFT-10), |
| datasize >> 10, |
| initsize >> 10); |
| |
| p3_cache_init(); |
| } |
| |
| void free_initmem(void) |
| { |
| unsigned long addr; |
| |
| addr = (unsigned long)(&__init_begin); |
| for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) { |
| ClearPageReserved(virt_to_page(addr)); |
| set_page_count(virt_to_page(addr), 1); |
| free_page(addr); |
| totalram_pages++; |
| } |
| printk ("Freeing unused kernel memory: %dk freed\n", (&__init_end - &__init_begin) >> 10); |
| } |
| |
| #ifdef CONFIG_BLK_DEV_INITRD |
| void free_initrd_mem(unsigned long start, unsigned long end) |
| { |
| unsigned long p; |
| for (p = start; p < end; p += PAGE_SIZE) { |
| ClearPageReserved(virt_to_page(p)); |
| set_page_count(virt_to_page(p), 1); |
| free_page(p); |
| totalram_pages++; |
| } |
| printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); |
| } |
| #endif |
| |