/* * Copyright (C) 2004-2006 Atmel Corporation * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_data; struct page *empty_zero_page; EXPORT_SYMBOL(empty_zero_page); /* * Cache of MMU context last used. */ unsigned long mmu_context_cache = NO_CONTEXT; /* * paging_init() sets up the page tables * * This routine 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) { extern unsigned long _evba; void *zero_page; int nid; /* * Make sure we can handle exceptions before enabling * paging. Not that we should ever _get_ any exceptions this * early, but you never know... */ printk("Exception vectors start at %p\n", &_evba); sysreg_write(EVBA, (unsigned long)&_evba); /* * Since we are ready to handle exceptions now, we should let * the CPU generate them... */ __asm__ __volatile__ ("csrf %0" : : "i"(SR_EM_BIT)); /* * Allocate the zero page. The allocator will panic if it * can't satisfy the request, so no need to check. */ zero_page = alloc_bootmem_low_pages_node(NODE_DATA(0), PAGE_SIZE); sysreg_write(PTBR, (unsigned long)swapper_pg_dir); enable_mmu(); printk ("CPU: Paging enabled\n"); for_each_online_node(nid) { pg_data_t *pgdat = NODE_DATA(nid); unsigned long zones_size[MAX_NR_ZONES]; unsigned long low, start_pfn; start_pfn = pgdat->bdata->node_min_pfn; low = pgdat->bdata->node_low_pfn; memset(zones_size, 0, sizeof(zones_size)); zones_size[ZONE_NORMAL] = low - start_pfn; printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n", nid, start_pfn, low); free_area_init_node(nid, zones_size, start_pfn, NULL); printk("Node %u: mem_map starts at %p\n", pgdat->node_id, pgdat->node_mem_map); } mem_map = NODE_DATA(0)->node_mem_map; empty_zero_page = virt_to_page(zero_page); flush_dcache_page(empty_zero_page); } void __init mem_init(void) { pg_data_t *pgdat; high_memory = NULL; /* this will put all low memory onto the freelists */ for_each_online_pgdat(pgdat) { void *node_high_memory; if (pgdat->node_spanned_pages != 0) free_all_bootmem_node(pgdat); node_high_memory = (void *)((pgdat->node_start_pfn + pgdat->node_spanned_pages) << PAGE_SHIFT); if (node_high_memory > high_memory) high_memory = node_high_memory; } max_mapnr = MAP_NR(high_memory); mem_init_print_info(NULL); } void free_initmem(void) { free_initmem_default(-1); } #ifdef CONFIG_BLK_DEV_INITRD void free_initrd_mem(unsigned long start, unsigned long end) { free_reserved_area((void *)start, (void *)end, -1, "initrd"); } #endif