/* * Copyright (C) 2007-2008 Michal Simek <monstr@monstr.eu> * Copyright (C) 2006 Atmark Techno, Inc. * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. */ #include <linux/bootmem.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/memblock.h> #include <linux/mm.h> /* mem_init */ #include <linux/initrd.h> #include <linux/pagemap.h> #include <linux/pfn.h> #include <linux/slab.h> #include <linux/swap.h> #include <linux/export.h> #include <asm/page.h> #include <asm/mmu_context.h> #include <asm/pgalloc.h> #include <asm/sections.h> #include <asm/tlb.h> #include <asm/fixmap.h> /* Use for MMU and noMMU because of PCI generic code */ int mem_init_done; #ifndef CONFIG_MMU unsigned int __page_offset; EXPORT_SYMBOL(__page_offset); #else static int init_bootmem_done; #endif /* CONFIG_MMU */ char *klimit = _end; /* * Initialize the bootmem system and give it all the memory we * have available. */ unsigned long memory_start; EXPORT_SYMBOL(memory_start); unsigned long memory_size; EXPORT_SYMBOL(memory_size); unsigned long lowmem_size; #ifdef CONFIG_HIGHMEM pte_t *kmap_pte; EXPORT_SYMBOL(kmap_pte); pgprot_t kmap_prot; EXPORT_SYMBOL(kmap_prot); static inline pte_t *virt_to_kpte(unsigned long vaddr) { return pte_offset_kernel(pmd_offset(pgd_offset_k(vaddr), vaddr), vaddr); } static void __init highmem_init(void) { pr_debug("%x\n", (u32)PKMAP_BASE); map_page(PKMAP_BASE, 0, 0); /* XXX gross */ pkmap_page_table = virt_to_kpte(PKMAP_BASE); kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN)); kmap_prot = PAGE_KERNEL; } static void highmem_setup(void) { unsigned long pfn; for (pfn = max_low_pfn; pfn < max_pfn; ++pfn) { struct page *page = pfn_to_page(pfn); /* FIXME not sure about */ if (!memblock_is_reserved(pfn << PAGE_SHIFT)) free_highmem_page(page); } } #endif /* CONFIG_HIGHMEM */ /* * paging_init() sets up the page tables - in fact we've already done this. */ static void __init paging_init(void) { unsigned long zones_size[MAX_NR_ZONES]; #ifdef CONFIG_MMU int idx; /* Setup fixmaps */ for (idx = 0; idx < __end_of_fixed_addresses; idx++) clear_fixmap(idx); #endif /* Clean every zones */ memset(zones_size, 0, sizeof(zones_size)); #ifdef CONFIG_HIGHMEM highmem_init(); zones_size[ZONE_DMA] = max_low_pfn; zones_size[ZONE_HIGHMEM] = max_pfn; #else zones_size[ZONE_DMA] = max_pfn; #endif /* We don't have holes in memory map */ free_area_init_nodes(zones_size); } void __init setup_memory(void) { unsigned long map_size; struct memblock_region *reg; #ifndef CONFIG_MMU u32 kernel_align_start, kernel_align_size; /* Find main memory where is the kernel */ for_each_memblock(memory, reg) { memory_start = (u32)reg->base; lowmem_size = reg->size; if ((memory_start <= (u32)_text) && ((u32)_text <= (memory_start + lowmem_size - 1))) { memory_size = lowmem_size; PAGE_OFFSET = memory_start; pr_info("%s: Main mem: 0x%x, size 0x%08x\n", __func__, (u32) memory_start, (u32) memory_size); break; } } if (!memory_start || !memory_size) { panic("%s: Missing memory setting 0x%08x, size=0x%08x\n", __func__, (u32) memory_start, (u32) memory_size); } /* reservation of region where is the kernel */ kernel_align_start = PAGE_DOWN((u32)_text); /* ALIGN can be remove because _end in vmlinux.lds.S is align */ kernel_align_size = PAGE_UP((u32)klimit) - kernel_align_start; pr_info("%s: kernel addr:0x%08x-0x%08x size=0x%08x\n", __func__, kernel_align_start, kernel_align_start + kernel_align_size, kernel_align_size); memblock_reserve(kernel_align_start, kernel_align_size); #endif /* * Kernel: * start: base phys address of kernel - page align * end: base phys address of kernel - page align * * min_low_pfn - the first page (mm/bootmem.c - node_boot_start) * max_low_pfn * max_mapnr - the first unused page (mm/bootmem.c - node_low_pfn) */ /* memory start is from the kernel end (aligned) to higher addr */ min_low_pfn = memory_start >> PAGE_SHIFT; /* minimum for allocation */ /* RAM is assumed contiguous */ max_mapnr = memory_size >> PAGE_SHIFT; max_low_pfn = ((u64)memory_start + (u64)lowmem_size) >> PAGE_SHIFT; max_pfn = ((u64)memory_start + (u64)memory_size) >> PAGE_SHIFT; pr_info("%s: max_mapnr: %#lx\n", __func__, max_mapnr); pr_info("%s: min_low_pfn: %#lx\n", __func__, min_low_pfn); pr_info("%s: max_low_pfn: %#lx\n", __func__, max_low_pfn); pr_info("%s: max_pfn: %#lx\n", __func__, max_pfn); /* * Find an area to use for the bootmem bitmap. * We look for the first area which is at least * 128kB in length (128kB is enough for a bitmap * for 4GB of memory, using 4kB pages), plus 1 page * (in case the address isn't page-aligned). */ map_size = init_bootmem_node(NODE_DATA(0), PFN_UP(TOPHYS((u32)klimit)), min_low_pfn, max_low_pfn); memblock_reserve(PFN_UP(TOPHYS((u32)klimit)) << PAGE_SHIFT, map_size); /* Add active regions with valid PFNs */ for_each_memblock(memory, reg) { unsigned long start_pfn, end_pfn; start_pfn = memblock_region_memory_base_pfn(reg); end_pfn = memblock_region_memory_end_pfn(reg); memblock_set_node(start_pfn << PAGE_SHIFT, (end_pfn - start_pfn) << PAGE_SHIFT, &memblock.memory, 0); } /* free bootmem is whole main memory */ free_bootmem_with_active_regions(0, max_low_pfn); /* reserve allocate blocks */ for_each_memblock(reserved, reg) { unsigned long top = reg->base + reg->size - 1; pr_debug("reserved - 0x%08x-0x%08x, %lx, %lx\n", (u32) reg->base, (u32) reg->size, top, memory_start + lowmem_size - 1); if (top <= (memory_start + lowmem_size - 1)) { reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT); } else if (reg->base < (memory_start + lowmem_size - 1)) { unsigned long trunc_size = memory_start + lowmem_size - reg->base; reserve_bootmem(reg->base, trunc_size, BOOTMEM_DEFAULT); } } /* XXX need to clip this if using highmem? */ sparse_memory_present_with_active_regions(0); #ifdef CONFIG_MMU init_bootmem_done = 1; #endif paging_init(); } #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 void free_initmem(void) { free_initmem_default(-1); } void __init mem_init(void) { high_memory = (void *)__va(memory_start + lowmem_size - 1); /* this will put all memory onto the freelists */ free_all_bootmem(); #ifdef CONFIG_HIGHMEM highmem_setup(); #endif mem_init_print_info(NULL); #ifdef CONFIG_MMU pr_info("Kernel virtual memory layout:\n"); pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); #ifdef CONFIG_HIGHMEM pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); #endif /* CONFIG_HIGHMEM */ pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", ioremap_bot, ioremap_base); pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", (unsigned long)VMALLOC_START, VMALLOC_END); #endif mem_init_done = 1; } #ifndef CONFIG_MMU int page_is_ram(unsigned long pfn) { return __range_ok(pfn, 0); } #else int page_is_ram(unsigned long pfn) { return pfn < max_low_pfn; } /* * Check for command-line options that affect what MMU_init will do. */ static void mm_cmdline_setup(void) { unsigned long maxmem = 0; char *p = cmd_line; /* Look for mem= option on command line */ p = strstr(cmd_line, "mem="); if (p) { p += 4; maxmem = memparse(p, &p); if (maxmem && memory_size > maxmem) { memory_size = maxmem; memblock.memory.regions[0].size = memory_size; } } } /* * MMU_init_hw does the chip-specific initialization of the MMU hardware. */ static void __init mmu_init_hw(void) { /* * The Zone Protection Register (ZPR) defines how protection will * be applied to every page which is a member of a given zone. At * present, we utilize only two of the zones. * The zone index bits (of ZSEL) in the PTE are used for software * indicators, except the LSB. For user access, zone 1 is used, * for kernel access, zone 0 is used. We set all but zone 1 * to zero, allowing only kernel access as indicated in the PTE. * For zone 1, we set a 01 binary (a value of 10 will not work) * to allow user access as indicated in the PTE. This also allows * kernel access as indicated in the PTE. */ __asm__ __volatile__ ("ori r11, r0, 0x10000000;" \ "mts rzpr, r11;" : : : "r11"); } /* * MMU_init sets up the basic memory mappings for the kernel, * including both RAM and possibly some I/O regions, * and sets up the page tables and the MMU hardware ready to go. */ /* called from head.S */ asmlinkage void __init mmu_init(void) { unsigned int kstart, ksize; if (!memblock.reserved.cnt) { pr_emerg("Error memory count\n"); machine_restart(NULL); } if ((u32) memblock.memory.regions[0].size < 0x400000) { pr_emerg("Memory must be greater than 4MB\n"); machine_restart(NULL); } if ((u32) memblock.memory.regions[0].size < kernel_tlb) { pr_emerg("Kernel size is greater than memory node\n"); machine_restart(NULL); } /* Find main memory where the kernel is */ memory_start = (u32) memblock.memory.regions[0].base; lowmem_size = memory_size = (u32) memblock.memory.regions[0].size; if (lowmem_size > CONFIG_LOWMEM_SIZE) { lowmem_size = CONFIG_LOWMEM_SIZE; #ifndef CONFIG_HIGHMEM memory_size = lowmem_size; #endif } mm_cmdline_setup(); /* FIXME parse args from command line - not used */ /* * Map out the kernel text/data/bss from the available physical * memory. */ kstart = __pa(CONFIG_KERNEL_START); /* kernel start */ /* kernel size */ ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START)); memblock_reserve(kstart, ksize); #if defined(CONFIG_BLK_DEV_INITRD) /* Remove the init RAM disk from the available memory. */ if (initrd_start) { unsigned long size; size = initrd_end - initrd_start; memblock_reserve(__virt_to_phys(initrd_start), size); } #endif /* CONFIG_BLK_DEV_INITRD */ /* Initialize the MMU hardware */ mmu_init_hw(); /* Map in all of RAM starting at CONFIG_KERNEL_START */ mapin_ram(); /* Extend vmalloc and ioremap area as big as possible */ #ifdef CONFIG_HIGHMEM ioremap_base = ioremap_bot = PKMAP_BASE; #else ioremap_base = ioremap_bot = FIXADDR_START; #endif /* Initialize the context management stuff */ mmu_context_init(); /* Shortly after that, the entire linear mapping will be available */ /* This will also cause that unflatten device tree will be allocated * inside 768MB limit */ memblock_set_current_limit(memory_start + lowmem_size - 1); } /* This is only called until mem_init is done. */ void __init *early_get_page(void) { void *p; if (init_bootmem_done) { p = alloc_bootmem_pages(PAGE_SIZE); } else { /* * Mem start + kernel_tlb -> here is limit * because of mem mapping from head.S */ p = __va(memblock_alloc_base(PAGE_SIZE, PAGE_SIZE, memory_start + kernel_tlb)); } return p; } #endif /* CONFIG_MMU */ void * __init_refok alloc_maybe_bootmem(size_t size, gfp_t mask) { if (mem_init_done) return kmalloc(size, mask); else return alloc_bootmem(size); } void * __init_refok zalloc_maybe_bootmem(size_t size, gfp_t mask) { void *p; if (mem_init_done) p = kzalloc(size, mask); else { p = alloc_bootmem(size); if (p) memset(p, 0, size); } return p; }