#include <linux/kernel.h> #include <linux/types.h> #include <linux/init.h> #include <linux/bootmem.h> #include <linux/ioport.h> #include <linux/string.h> #include <linux/kexec.h> #include <linux/module.h> #include <linux/mm.h> #include <linux/efi.h> #include <linux/pfn.h> #include <linux/uaccess.h> #include <asm/pgtable.h> #include <asm/page.h> #include <asm/e820.h> #include <asm/setup.h> #ifdef CONFIG_EFI int efi_enabled = 0; EXPORT_SYMBOL(efi_enabled); #endif struct e820map e820; struct change_member { struct e820entry *pbios; /* pointer to original bios entry */ unsigned long long addr; /* address for this change point */ }; static struct change_member change_point_list[2*E820MAX] __initdata; static struct change_member *change_point[2*E820MAX] __initdata; static struct e820entry *overlap_list[E820MAX] __initdata; static struct e820entry new_bios[E820MAX] __initdata; /* For PCI or other memory-mapped resources */ unsigned long pci_mem_start = 0x10000000; #ifdef CONFIG_PCI EXPORT_SYMBOL(pci_mem_start); #endif extern int user_defined_memmap; struct resource data_resource = { .name = "Kernel data", .start = 0, .end = 0, .flags = IORESOURCE_BUSY | IORESOURCE_MEM }; struct resource code_resource = { .name = "Kernel code", .start = 0, .end = 0, .flags = IORESOURCE_BUSY | IORESOURCE_MEM }; static struct resource system_rom_resource = { .name = "System ROM", .start = 0xf0000, .end = 0xfffff, .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM }; static struct resource extension_rom_resource = { .name = "Extension ROM", .start = 0xe0000, .end = 0xeffff, .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM }; static struct resource adapter_rom_resources[] = { { .name = "Adapter ROM", .start = 0xc8000, .end = 0, .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM }, { .name = "Adapter ROM", .start = 0, .end = 0, .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM }, { .name = "Adapter ROM", .start = 0, .end = 0, .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM }, { .name = "Adapter ROM", .start = 0, .end = 0, .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM }, { .name = "Adapter ROM", .start = 0, .end = 0, .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM }, { .name = "Adapter ROM", .start = 0, .end = 0, .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM } }; static struct resource video_rom_resource = { .name = "Video ROM", .start = 0xc0000, .end = 0xc7fff, .flags = IORESOURCE_BUSY | IORESOURCE_READONLY | IORESOURCE_MEM }; static struct resource video_ram_resource = { .name = "Video RAM area", .start = 0xa0000, .end = 0xbffff, .flags = IORESOURCE_BUSY | IORESOURCE_MEM }; static struct resource standard_io_resources[] = { { .name = "dma1", .start = 0x0000, .end = 0x001f, .flags = IORESOURCE_BUSY | IORESOURCE_IO }, { .name = "pic1", .start = 0x0020, .end = 0x0021, .flags = IORESOURCE_BUSY | IORESOURCE_IO }, { .name = "timer0", .start = 0x0040, .end = 0x0043, .flags = IORESOURCE_BUSY | IORESOURCE_IO }, { .name = "timer1", .start = 0x0050, .end = 0x0053, .flags = IORESOURCE_BUSY | IORESOURCE_IO }, { .name = "keyboard", .start = 0x0060, .end = 0x006f, .flags = IORESOURCE_BUSY | IORESOURCE_IO }, { .name = "dma page reg", .start = 0x0080, .end = 0x008f, .flags = IORESOURCE_BUSY | IORESOURCE_IO }, { .name = "pic2", .start = 0x00a0, .end = 0x00a1, .flags = IORESOURCE_BUSY | IORESOURCE_IO }, { .name = "dma2", .start = 0x00c0, .end = 0x00df, .flags = IORESOURCE_BUSY | IORESOURCE_IO }, { .name = "fpu", .start = 0x00f0, .end = 0x00ff, .flags = IORESOURCE_BUSY | IORESOURCE_IO } }; #define ROMSIGNATURE 0xaa55 static int __init romsignature(const unsigned char *rom) { const unsigned short * const ptr = (const unsigned short *)rom; unsigned short sig; return probe_kernel_address(ptr, sig) == 0 && sig == ROMSIGNATURE; } static int __init romchecksum(const unsigned char *rom, unsigned long length) { unsigned char sum, c; for (sum = 0; length && probe_kernel_address(rom++, c) == 0; length--) sum += c; return !length && !sum; } static void __init probe_roms(void) { const unsigned char *rom; unsigned long start, length, upper; unsigned char c; int i; /* video rom */ upper = adapter_rom_resources[0].start; for (start = video_rom_resource.start; start < upper; start += 2048) { rom = isa_bus_to_virt(start); if (!romsignature(rom)) continue; video_rom_resource.start = start; if (probe_kernel_address(rom + 2, c) != 0) continue; /* 0 < length <= 0x7f * 512, historically */ length = c * 512; /* if checksum okay, trust length byte */ if (length && romchecksum(rom, length)) video_rom_resource.end = start + length - 1; request_resource(&iomem_resource, &video_rom_resource); break; } start = (video_rom_resource.end + 1 + 2047) & ~2047UL; if (start < upper) start = upper; /* system rom */ request_resource(&iomem_resource, &system_rom_resource); upper = system_rom_resource.start; /* check for extension rom (ignore length byte!) */ rom = isa_bus_to_virt(extension_rom_resource.start); if (romsignature(rom)) { length = extension_rom_resource.end - extension_rom_resource.start + 1; if (romchecksum(rom, length)) { request_resource(&iomem_resource, &extension_rom_resource); upper = extension_rom_resource.start; } } /* check for adapter roms on 2k boundaries */ for (i = 0; i < ARRAY_SIZE(adapter_rom_resources) && start < upper; start += 2048) { rom = isa_bus_to_virt(start); if (!romsignature(rom)) continue; if (probe_kernel_address(rom + 2, c) != 0) continue; /* 0 < length <= 0x7f * 512, historically */ length = c * 512; /* but accept any length that fits if checksum okay */ if (!length || start + length > upper || !romchecksum(rom, length)) continue; adapter_rom_resources[i].start = start; adapter_rom_resources[i].end = start + length - 1; request_resource(&iomem_resource, &adapter_rom_resources[i]); start = adapter_rom_resources[i++].end & ~2047UL; } } /* * Request address space for all standard RAM and ROM resources * and also for regions reported as reserved by the e820. */ static void __init legacy_init_iomem_resources(struct resource *code_resource, struct resource *data_resource) { int i; probe_roms(); for (i = 0; i < e820.nr_map; i++) { struct resource *res; #ifndef CONFIG_RESOURCES_64BIT if (e820.map[i].addr + e820.map[i].size > 0x100000000ULL) continue; #endif res = kzalloc(sizeof(struct resource), GFP_ATOMIC); switch (e820.map[i].type) { case E820_RAM: res->name = "System RAM"; break; case E820_ACPI: res->name = "ACPI Tables"; break; case E820_NVS: res->name = "ACPI Non-volatile Storage"; break; default: res->name = "reserved"; } res->start = e820.map[i].addr; res->end = res->start + e820.map[i].size - 1; res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; if (request_resource(&iomem_resource, res)) { kfree(res); continue; } if (e820.map[i].type == E820_RAM) { /* * We don't know which RAM region contains kernel data, * so we try it repeatedly and let the resource manager * test it. */ request_resource(res, code_resource); request_resource(res, data_resource); #ifdef CONFIG_KEXEC request_resource(res, &crashk_res); #endif } } } /* * Request address space for all standard resources * * This is called just before pcibios_init(), which is also a * subsys_initcall, but is linked in later (in arch/i386/pci/common.c). */ static int __init request_standard_resources(void) { int i; printk("Setting up standard PCI resources\n"); if (efi_enabled) efi_initialize_iomem_resources(&code_resource, &data_resource); else legacy_init_iomem_resources(&code_resource, &data_resource); /* EFI systems may still have VGA */ request_resource(&iomem_resource, &video_ram_resource); /* request I/O space for devices used on all i[345]86 PCs */ for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++) request_resource(&ioport_resource, &standard_io_resources[i]); return 0; } subsys_initcall(request_standard_resources); void __init add_memory_region(unsigned long long start, unsigned long long size, int type) { int x; if (!efi_enabled) { x = e820.nr_map; if (x == E820MAX) { printk(KERN_ERR "Ooops! Too many entries in the memory map!\n"); return; } e820.map[x].addr = start; e820.map[x].size = size; e820.map[x].type = type; e820.nr_map++; } } /* add_memory_region */ /* * Sanitize the BIOS e820 map. * * Some e820 responses include overlapping entries. The following * replaces the original e820 map with a new one, removing overlaps. * */ int __init sanitize_e820_map(struct e820entry * biosmap, char * pnr_map) { struct change_member *change_tmp; unsigned long current_type, last_type; unsigned long long last_addr; int chgidx, still_changing; int overlap_entries; int new_bios_entry; int old_nr, new_nr, chg_nr; int i; /* Visually we're performing the following (1,2,3,4 = memory types)... Sample memory map (w/overlaps): ____22__________________ ______________________4_ ____1111________________ _44_____________________ 11111111________________ ____________________33__ ___________44___________ __________33333_________ ______________22________ ___________________2222_ _________111111111______ _____________________11_ _________________4______ Sanitized equivalent (no overlap): 1_______________________ _44_____________________ ___1____________________ ____22__________________ ______11________________ _________1______________ __________3_____________ ___________44___________ _____________33_________ _______________2________ ________________1_______ _________________4______ ___________________2____ ____________________33__ ______________________4_ */ printk("sanitize start\n"); /* if there's only one memory region, don't bother */ if (*pnr_map < 2) { printk("sanitize bail 0\n"); return -1; } old_nr = *pnr_map; /* bail out if we find any unreasonable addresses in bios map */ for (i=0; i<old_nr; i++) if (biosmap[i].addr + biosmap[i].size < biosmap[i].addr) { printk("sanitize bail 1\n"); return -1; } /* create pointers for initial change-point information (for sorting) */ for (i=0; i < 2*old_nr; i++) change_point[i] = &change_point_list[i]; /* record all known change-points (starting and ending addresses), omitting those that are for empty memory regions */ chgidx = 0; for (i=0; i < old_nr; i++) { if (biosmap[i].size != 0) { change_point[chgidx]->addr = biosmap[i].addr; change_point[chgidx++]->pbios = &biosmap[i]; change_point[chgidx]->addr = biosmap[i].addr + biosmap[i].size; change_point[chgidx++]->pbios = &biosmap[i]; } } chg_nr = chgidx; /* true number of change-points */ /* sort change-point list by memory addresses (low -> high) */ still_changing = 1; while (still_changing) { still_changing = 0; for (i=1; i < chg_nr; i++) { /* if <current_addr> > <last_addr>, swap */ /* or, if current=<start_addr> & last=<end_addr>, swap */ if ((change_point[i]->addr < change_point[i-1]->addr) || ((change_point[i]->addr == change_point[i-1]->addr) && (change_point[i]->addr == change_point[i]->pbios->addr) && (change_point[i-1]->addr != change_point[i-1]->pbios->addr)) ) { change_tmp = change_point[i]; change_point[i] = change_point[i-1]; change_point[i-1] = change_tmp; still_changing=1; } } } /* create a new bios memory map, removing overlaps */ overlap_entries=0; /* number of entries in the overlap table */ new_bios_entry=0; /* index for creating new bios map entries */ last_type = 0; /* start with undefined memory type */ last_addr = 0; /* start with 0 as last starting address */ /* loop through change-points, determining affect on the new bios map */ for (chgidx=0; chgidx < chg_nr; chgidx++) { /* keep track of all overlapping bios entries */ if (change_point[chgidx]->addr == change_point[chgidx]->pbios->addr) { /* add map entry to overlap list (> 1 entry implies an overlap) */ overlap_list[overlap_entries++]=change_point[chgidx]->pbios; } else { /* remove entry from list (order independent, so swap with last) */ for (i=0; i<overlap_entries; i++) { if (overlap_list[i] == change_point[chgidx]->pbios) overlap_list[i] = overlap_list[overlap_entries-1]; } overlap_entries--; } /* if there are overlapping entries, decide which "type" to use */ /* (larger value takes precedence -- 1=usable, 2,3,4,4+=unusable) */ current_type = 0; for (i=0; i<overlap_entries; i++) if (overlap_list[i]->type > current_type) current_type = overlap_list[i]->type; /* continue building up new bios map based on this information */ if (current_type != last_type) { if (last_type != 0) { new_bios[new_bios_entry].size = change_point[chgidx]->addr - last_addr; /* move forward only if the new size was non-zero */ if (new_bios[new_bios_entry].size != 0) if (++new_bios_entry >= E820MAX) break; /* no more space left for new bios entries */ } if (current_type != 0) { new_bios[new_bios_entry].addr = change_point[chgidx]->addr; new_bios[new_bios_entry].type = current_type; last_addr=change_point[chgidx]->addr; } last_type = current_type; } } new_nr = new_bios_entry; /* retain count for new bios entries */ /* copy new bios mapping into original location */ memcpy(biosmap, new_bios, new_nr*sizeof(struct e820entry)); *pnr_map = new_nr; printk("sanitize end\n"); return 0; } /* * Copy the BIOS e820 map into a safe place. * * Sanity-check it while we're at it.. * * If we're lucky and live on a modern system, the setup code * will have given us a memory map that we can use to properly * set up memory. If we aren't, we'll fake a memory map. * * We check to see that the memory map contains at least 2 elements * before we'll use it, because the detection code in setup.S may * not be perfect and most every PC known to man has two memory * regions: one from 0 to 640k, and one from 1mb up. (The IBM * thinkpad 560x, for example, does not cooperate with the memory * detection code.) */ int __init copy_e820_map(struct e820entry * biosmap, int nr_map) { /* Only one memory region (or negative)? Ignore it */ if (nr_map < 2) return -1; do { unsigned long long start = biosmap->addr; unsigned long long size = biosmap->size; unsigned long long end = start + size; unsigned long type = biosmap->type; printk("copy_e820_map() start: %016Lx size: %016Lx end: %016Lx type: %ld\n", start, size, end, type); /* Overflow in 64 bits? Ignore the memory map. */ if (start > end) return -1; /* * Some BIOSes claim RAM in the 640k - 1M region. * Not right. Fix it up. */ if (type == E820_RAM) { printk("copy_e820_map() type is E820_RAM\n"); if (start < 0x100000ULL && end > 0xA0000ULL) { printk("copy_e820_map() lies in range...\n"); if (start < 0xA0000ULL) { printk("copy_e820_map() start < 0xA0000ULL\n"); add_memory_region(start, 0xA0000ULL-start, type); } if (end <= 0x100000ULL) { printk("copy_e820_map() end <= 0x100000ULL\n"); continue; } start = 0x100000ULL; size = end - start; } } add_memory_region(start, size, type); } while (biosmap++,--nr_map); return 0; } /* * Callback for efi_memory_walk. */ static int __init efi_find_max_pfn(unsigned long start, unsigned long end, void *arg) { unsigned long *max_pfn = arg, pfn; if (start < end) { pfn = PFN_UP(end -1); if (pfn > *max_pfn) *max_pfn = pfn; } return 0; } static int __init efi_memory_present_wrapper(unsigned long start, unsigned long end, void *arg) { memory_present(0, PFN_UP(start), PFN_DOWN(end)); return 0; } /* * Find the highest page frame number we have available */ void __init find_max_pfn(void) { int i; max_pfn = 0; if (efi_enabled) { efi_memmap_walk(efi_find_max_pfn, &max_pfn); efi_memmap_walk(efi_memory_present_wrapper, NULL); return; } for (i = 0; i < e820.nr_map; i++) { unsigned long start, end; /* RAM? */ if (e820.map[i].type != E820_RAM) continue; start = PFN_UP(e820.map[i].addr); end = PFN_DOWN(e820.map[i].addr + e820.map[i].size); if (start >= end) continue; if (end > max_pfn) max_pfn = end; memory_present(0, start, end); } } /* * Free all available memory for boot time allocation. Used * as a callback function by efi_memory_walk() */ static int __init free_available_memory(unsigned long start, unsigned long end, void *arg) { /* check max_low_pfn */ if (start >= (max_low_pfn << PAGE_SHIFT)) return 0; if (end >= (max_low_pfn << PAGE_SHIFT)) end = max_low_pfn << PAGE_SHIFT; if (start < end) free_bootmem(start, end - start); return 0; } /* * Register fully available low RAM pages with the bootmem allocator. */ void __init register_bootmem_low_pages(unsigned long max_low_pfn) { int i; if (efi_enabled) { efi_memmap_walk(free_available_memory, NULL); return; } for (i = 0; i < e820.nr_map; i++) { unsigned long curr_pfn, last_pfn, size; /* * Reserve usable low memory */ if (e820.map[i].type != E820_RAM) continue; /* * We are rounding up the start address of usable memory: */ curr_pfn = PFN_UP(e820.map[i].addr); if (curr_pfn >= max_low_pfn) continue; /* * ... and at the end of the usable range downwards: */ last_pfn = PFN_DOWN(e820.map[i].addr + e820.map[i].size); if (last_pfn > max_low_pfn) last_pfn = max_low_pfn; /* * .. finally, did all the rounding and playing * around just make the area go away? */ if (last_pfn <= curr_pfn) continue; size = last_pfn - curr_pfn; free_bootmem(PFN_PHYS(curr_pfn), PFN_PHYS(size)); } } void __init e820_register_memory(void) { unsigned long gapstart, gapsize, round; unsigned long long last; int i; /* * Search for the bigest gap in the low 32 bits of the e820 * memory space. */ last = 0x100000000ull; gapstart = 0x10000000; gapsize = 0x400000; i = e820.nr_map; while (--i >= 0) { unsigned long long start = e820.map[i].addr; unsigned long long end = start + e820.map[i].size; /* * Since "last" is at most 4GB, we know we'll * fit in 32 bits if this condition is true */ if (last > end) { unsigned long gap = last - end; if (gap > gapsize) { gapsize = gap; gapstart = end; } } if (start < last) last = start; } /* * See how much we want to round up: start off with * rounding to the next 1MB area. */ round = 0x100000; while ((gapsize >> 4) > round) round += round; /* Fun with two's complement */ pci_mem_start = (gapstart + round) & -round; printk("Allocating PCI resources starting at %08lx (gap: %08lx:%08lx)\n", pci_mem_start, gapstart, gapsize); } void __init print_memory_map(char *who) { int i; for (i = 0; i < e820.nr_map; i++) { printk(" %s: %016Lx - %016Lx ", who, e820.map[i].addr, e820.map[i].addr + e820.map[i].size); switch (e820.map[i].type) { case E820_RAM: printk("(usable)\n"); break; case E820_RESERVED: printk("(reserved)\n"); break; case E820_ACPI: printk("(ACPI data)\n"); break; case E820_NVS: printk("(ACPI NVS)\n"); break; default: printk("type %lu\n", e820.map[i].type); break; } } } static __init __always_inline void efi_limit_regions(unsigned long long size) { unsigned long long current_addr = 0; efi_memory_desc_t *md, *next_md; void *p, *p1; int i, j; j = 0; p1 = memmap.map; for (p = p1, i = 0; p < memmap.map_end; p += memmap.desc_size, i++) { md = p; next_md = p1; current_addr = md->phys_addr + PFN_PHYS(md->num_pages); if (is_available_memory(md)) { if (md->phys_addr >= size) continue; memcpy(next_md, md, memmap.desc_size); if (current_addr >= size) { next_md->num_pages -= PFN_UP(current_addr-size); } p1 += memmap.desc_size; next_md = p1; j++; } else if ((md->attribute & EFI_MEMORY_RUNTIME) == EFI_MEMORY_RUNTIME) { /* In order to make runtime services * available we have to include runtime * memory regions in memory map */ memcpy(next_md, md, memmap.desc_size); p1 += memmap.desc_size; next_md = p1; j++; } } memmap.nr_map = j; memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size); } void __init limit_regions(unsigned long long size) { unsigned long long current_addr; int i; print_memory_map("limit_regions start"); if (efi_enabled) { efi_limit_regions(size); return; } for (i = 0; i < e820.nr_map; i++) { current_addr = e820.map[i].addr + e820.map[i].size; if (current_addr < size) continue; if (e820.map[i].type != E820_RAM) continue; if (e820.map[i].addr >= size) { /* * This region starts past the end of the * requested size, skip it completely. */ e820.nr_map = i; } else { e820.nr_map = i + 1; e820.map[i].size -= current_addr - size; } print_memory_map("limit_regions endfor"); return; } print_memory_map("limit_regions endfunc"); } /* * This function checks if any part of the range <start,end> is mapped * with type. */ int e820_any_mapped(u64 start, u64 end, unsigned type) { int i; for (i = 0; i < e820.nr_map; i++) { const struct e820entry *ei = &e820.map[i]; if (type && ei->type != type) continue; if (ei->addr >= end || ei->addr + ei->size <= start) continue; return 1; } return 0; } EXPORT_SYMBOL_GPL(e820_any_mapped); /* * This function checks if the entire range <start,end> is mapped with type. * * Note: this function only works correct if the e820 table is sorted and * not-overlapping, which is the case */ int __init e820_all_mapped(unsigned long s, unsigned long e, unsigned type) { u64 start = s; u64 end = e; int i; for (i = 0; i < e820.nr_map; i++) { struct e820entry *ei = &e820.map[i]; if (type && ei->type != type) continue; /* is the region (part) in overlap with the current region ?*/ if (ei->addr >= end || ei->addr + ei->size <= start) continue; /* if the region is at the beginning of <start,end> we move * start to the end of the region since it's ok until there */ if (ei->addr <= start) start = ei->addr + ei->size; /* if start is now at or beyond end, we're done, full * coverage */ if (start >= end) return 1; /* we're done */ } return 0; } static int __init parse_memmap(char *arg) { if (!arg) return -EINVAL; if (strcmp(arg, "exactmap") == 0) { #ifdef CONFIG_CRASH_DUMP /* If we are doing a crash dump, we * still need to know the real mem * size before original memory map is * reset. */ find_max_pfn(); saved_max_pfn = max_pfn; #endif e820.nr_map = 0; user_defined_memmap = 1; } else { /* If the user specifies memory size, we * limit the BIOS-provided memory map to * that size. exactmap can be used to specify * the exact map. mem=number can be used to * trim the existing memory map. */ unsigned long long start_at, mem_size; mem_size = memparse(arg, &arg); if (*arg == '@') { start_at = memparse(arg+1, &arg); add_memory_region(start_at, mem_size, E820_RAM); } else if (*arg == '#') { start_at = memparse(arg+1, &arg); add_memory_region(start_at, mem_size, E820_ACPI); } else if (*arg == '$') { start_at = memparse(arg+1, &arg); add_memory_region(start_at, mem_size, E820_RESERVED); } else { limit_regions(mem_size); user_defined_memmap = 1; } } return 0; } early_param("memmap", parse_memmap);