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path: root/drivers/firmware/dmi_scan.c
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Diffstat (limited to 'drivers/firmware/dmi_scan.c')
-rw-r--r--drivers/firmware/dmi_scan.c945
1 files changed, 945 insertions, 0 deletions
diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c
new file mode 100644
index 000000000..bba843c2b
--- /dev/null
+++ b/drivers/firmware/dmi_scan.c
@@ -0,0 +1,945 @@
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/ctype.h>
+#include <linux/dmi.h>
+#include <linux/efi.h>
+#include <linux/bootmem.h>
+#include <linux/random.h>
+#include <asm/dmi.h>
+#include <asm/unaligned.h>
+
+/*
+ * DMI stands for "Desktop Management Interface". It is part
+ * of and an antecedent to, SMBIOS, which stands for System
+ * Management BIOS. See further: http://www.dmtf.org/standards
+ */
+static const char dmi_empty_string[] = " ";
+
+static u32 dmi_ver __initdata;
+static u32 dmi_len;
+static u16 dmi_num;
+/*
+ * Catch too early calls to dmi_check_system():
+ */
+static int dmi_initialized;
+
+/* DMI system identification string used during boot */
+static char dmi_ids_string[128] __initdata;
+
+static struct dmi_memdev_info {
+ const char *device;
+ const char *bank;
+ u16 handle;
+} *dmi_memdev;
+static int dmi_memdev_nr;
+
+static const char * __init dmi_string_nosave(const struct dmi_header *dm, u8 s)
+{
+ const u8 *bp = ((u8 *) dm) + dm->length;
+
+ if (s) {
+ s--;
+ while (s > 0 && *bp) {
+ bp += strlen(bp) + 1;
+ s--;
+ }
+
+ if (*bp != 0) {
+ size_t len = strlen(bp)+1;
+ size_t cmp_len = len > 8 ? 8 : len;
+
+ if (!memcmp(bp, dmi_empty_string, cmp_len))
+ return dmi_empty_string;
+ return bp;
+ }
+ }
+
+ return "";
+}
+
+static const char * __init dmi_string(const struct dmi_header *dm, u8 s)
+{
+ const char *bp = dmi_string_nosave(dm, s);
+ char *str;
+ size_t len;
+
+ if (bp == dmi_empty_string)
+ return dmi_empty_string;
+
+ len = strlen(bp) + 1;
+ str = dmi_alloc(len);
+ if (str != NULL)
+ strcpy(str, bp);
+
+ return str;
+}
+
+/*
+ * We have to be cautious here. We have seen BIOSes with DMI pointers
+ * pointing to completely the wrong place for example
+ */
+static void dmi_table(u8 *buf,
+ void (*decode)(const struct dmi_header *, void *),
+ void *private_data)
+{
+ u8 *data = buf;
+ int i = 0;
+
+ /*
+ * Stop when we have seen all the items the table claimed to have
+ * (SMBIOS < 3.0 only) OR we reach an end-of-table marker (SMBIOS
+ * >= 3.0 only) OR we run off the end of the table (should never
+ * happen but sometimes does on bogus implementations.)
+ */
+ while ((!dmi_num || i < dmi_num) &&
+ (data - buf + sizeof(struct dmi_header)) <= dmi_len) {
+ const struct dmi_header *dm = (const struct dmi_header *)data;
+
+ /*
+ * We want to know the total length (formatted area and
+ * strings) before decoding to make sure we won't run off the
+ * table in dmi_decode or dmi_string
+ */
+ data += dm->length;
+ while ((data - buf < dmi_len - 1) && (data[0] || data[1]))
+ data++;
+ if (data - buf < dmi_len - 1)
+ decode(dm, private_data);
+
+ /*
+ * 7.45 End-of-Table (Type 127) [SMBIOS reference spec v3.0.0]
+ * For tables behind a 64-bit entry point, we have no item
+ * count and no exact table length, so stop on end-of-table
+ * marker. For tables behind a 32-bit entry point, we have
+ * seen OEM structures behind the end-of-table marker on
+ * some systems, so don't trust it.
+ */
+ if (!dmi_num && dm->type == DMI_ENTRY_END_OF_TABLE)
+ break;
+
+ data += 2;
+ i++;
+ }
+}
+
+static phys_addr_t dmi_base;
+
+static int __init dmi_walk_early(void (*decode)(const struct dmi_header *,
+ void *))
+{
+ u8 *buf;
+
+ buf = dmi_early_remap(dmi_base, dmi_len);
+ if (buf == NULL)
+ return -1;
+
+ dmi_table(buf, decode, NULL);
+
+ add_device_randomness(buf, dmi_len);
+
+ dmi_early_unmap(buf, dmi_len);
+ return 0;
+}
+
+static int __init dmi_checksum(const u8 *buf, u8 len)
+{
+ u8 sum = 0;
+ int a;
+
+ for (a = 0; a < len; a++)
+ sum += buf[a];
+
+ return sum == 0;
+}
+
+static const char *dmi_ident[DMI_STRING_MAX];
+static LIST_HEAD(dmi_devices);
+int dmi_available;
+
+/*
+ * Save a DMI string
+ */
+static void __init dmi_save_ident(const struct dmi_header *dm, int slot,
+ int string)
+{
+ const char *d = (const char *) dm;
+ const char *p;
+
+ if (dmi_ident[slot])
+ return;
+
+ p = dmi_string(dm, d[string]);
+ if (p == NULL)
+ return;
+
+ dmi_ident[slot] = p;
+}
+
+static void __init dmi_save_uuid(const struct dmi_header *dm, int slot,
+ int index)
+{
+ const u8 *d = (u8 *) dm + index;
+ char *s;
+ int is_ff = 1, is_00 = 1, i;
+
+ if (dmi_ident[slot])
+ return;
+
+ for (i = 0; i < 16 && (is_ff || is_00); i++) {
+ if (d[i] != 0x00)
+ is_00 = 0;
+ if (d[i] != 0xFF)
+ is_ff = 0;
+ }
+
+ if (is_ff || is_00)
+ return;
+
+ s = dmi_alloc(16*2+4+1);
+ if (!s)
+ return;
+
+ /*
+ * As of version 2.6 of the SMBIOS specification, the first 3 fields of
+ * the UUID are supposed to be little-endian encoded. The specification
+ * says that this is the defacto standard.
+ */
+ if (dmi_ver >= 0x020600)
+ sprintf(s, "%pUL", d);
+ else
+ sprintf(s, "%pUB", d);
+
+ dmi_ident[slot] = s;
+}
+
+static void __init dmi_save_type(const struct dmi_header *dm, int slot,
+ int index)
+{
+ const u8 *d = (u8 *) dm + index;
+ char *s;
+
+ if (dmi_ident[slot])
+ return;
+
+ s = dmi_alloc(4);
+ if (!s)
+ return;
+
+ sprintf(s, "%u", *d & 0x7F);
+ dmi_ident[slot] = s;
+}
+
+static void __init dmi_save_one_device(int type, const char *name)
+{
+ struct dmi_device *dev;
+
+ /* No duplicate device */
+ if (dmi_find_device(type, name, NULL))
+ return;
+
+ dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
+ if (!dev)
+ return;
+
+ dev->type = type;
+ strcpy((char *)(dev + 1), name);
+ dev->name = (char *)(dev + 1);
+ dev->device_data = NULL;
+ list_add(&dev->list, &dmi_devices);
+}
+
+static void __init dmi_save_devices(const struct dmi_header *dm)
+{
+ int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
+
+ for (i = 0; i < count; i++) {
+ const char *d = (char *)(dm + 1) + (i * 2);
+
+ /* Skip disabled device */
+ if ((*d & 0x80) == 0)
+ continue;
+
+ dmi_save_one_device(*d & 0x7f, dmi_string_nosave(dm, *(d + 1)));
+ }
+}
+
+static void __init dmi_save_oem_strings_devices(const struct dmi_header *dm)
+{
+ int i, count = *(u8 *)(dm + 1);
+ struct dmi_device *dev;
+
+ for (i = 1; i <= count; i++) {
+ const char *devname = dmi_string(dm, i);
+
+ if (devname == dmi_empty_string)
+ continue;
+
+ dev = dmi_alloc(sizeof(*dev));
+ if (!dev)
+ break;
+
+ dev->type = DMI_DEV_TYPE_OEM_STRING;
+ dev->name = devname;
+ dev->device_data = NULL;
+
+ list_add(&dev->list, &dmi_devices);
+ }
+}
+
+static void __init dmi_save_ipmi_device(const struct dmi_header *dm)
+{
+ struct dmi_device *dev;
+ void *data;
+
+ data = dmi_alloc(dm->length);
+ if (data == NULL)
+ return;
+
+ memcpy(data, dm, dm->length);
+
+ dev = dmi_alloc(sizeof(*dev));
+ if (!dev)
+ return;
+
+ dev->type = DMI_DEV_TYPE_IPMI;
+ dev->name = "IPMI controller";
+ dev->device_data = data;
+
+ list_add_tail(&dev->list, &dmi_devices);
+}
+
+static void __init dmi_save_dev_onboard(int instance, int segment, int bus,
+ int devfn, const char *name)
+{
+ struct dmi_dev_onboard *onboard_dev;
+
+ onboard_dev = dmi_alloc(sizeof(*onboard_dev) + strlen(name) + 1);
+ if (!onboard_dev)
+ return;
+
+ onboard_dev->instance = instance;
+ onboard_dev->segment = segment;
+ onboard_dev->bus = bus;
+ onboard_dev->devfn = devfn;
+
+ strcpy((char *)&onboard_dev[1], name);
+ onboard_dev->dev.type = DMI_DEV_TYPE_DEV_ONBOARD;
+ onboard_dev->dev.name = (char *)&onboard_dev[1];
+ onboard_dev->dev.device_data = onboard_dev;
+
+ list_add(&onboard_dev->dev.list, &dmi_devices);
+}
+
+static void __init dmi_save_extended_devices(const struct dmi_header *dm)
+{
+ const u8 *d = (u8 *) dm + 5;
+
+ /* Skip disabled device */
+ if ((*d & 0x80) == 0)
+ return;
+
+ dmi_save_dev_onboard(*(d+1), *(u16 *)(d+2), *(d+4), *(d+5),
+ dmi_string_nosave(dm, *(d-1)));
+ dmi_save_one_device(*d & 0x7f, dmi_string_nosave(dm, *(d - 1)));
+}
+
+static void __init count_mem_devices(const struct dmi_header *dm, void *v)
+{
+ if (dm->type != DMI_ENTRY_MEM_DEVICE)
+ return;
+ dmi_memdev_nr++;
+}
+
+static void __init save_mem_devices(const struct dmi_header *dm, void *v)
+{
+ const char *d = (const char *)dm;
+ static int nr;
+
+ if (dm->type != DMI_ENTRY_MEM_DEVICE)
+ return;
+ if (nr >= dmi_memdev_nr) {
+ pr_warn(FW_BUG "Too many DIMM entries in SMBIOS table\n");
+ return;
+ }
+ dmi_memdev[nr].handle = get_unaligned(&dm->handle);
+ dmi_memdev[nr].device = dmi_string(dm, d[0x10]);
+ dmi_memdev[nr].bank = dmi_string(dm, d[0x11]);
+ nr++;
+}
+
+void __init dmi_memdev_walk(void)
+{
+ if (!dmi_available)
+ return;
+
+ if (dmi_walk_early(count_mem_devices) == 0 && dmi_memdev_nr) {
+ dmi_memdev = dmi_alloc(sizeof(*dmi_memdev) * dmi_memdev_nr);
+ if (dmi_memdev)
+ dmi_walk_early(save_mem_devices);
+ }
+}
+
+/*
+ * Process a DMI table entry. Right now all we care about are the BIOS
+ * and machine entries. For 2.5 we should pull the smbus controller info
+ * out of here.
+ */
+static void __init dmi_decode(const struct dmi_header *dm, void *dummy)
+{
+ switch (dm->type) {
+ case 0: /* BIOS Information */
+ dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
+ dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
+ dmi_save_ident(dm, DMI_BIOS_DATE, 8);
+ break;
+ case 1: /* System Information */
+ dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
+ dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
+ dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
+ dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
+ dmi_save_uuid(dm, DMI_PRODUCT_UUID, 8);
+ break;
+ case 2: /* Base Board Information */
+ dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
+ dmi_save_ident(dm, DMI_BOARD_NAME, 5);
+ dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
+ dmi_save_ident(dm, DMI_BOARD_SERIAL, 7);
+ dmi_save_ident(dm, DMI_BOARD_ASSET_TAG, 8);
+ break;
+ case 3: /* Chassis Information */
+ dmi_save_ident(dm, DMI_CHASSIS_VENDOR, 4);
+ dmi_save_type(dm, DMI_CHASSIS_TYPE, 5);
+ dmi_save_ident(dm, DMI_CHASSIS_VERSION, 6);
+ dmi_save_ident(dm, DMI_CHASSIS_SERIAL, 7);
+ dmi_save_ident(dm, DMI_CHASSIS_ASSET_TAG, 8);
+ break;
+ case 10: /* Onboard Devices Information */
+ dmi_save_devices(dm);
+ break;
+ case 11: /* OEM Strings */
+ dmi_save_oem_strings_devices(dm);
+ break;
+ case 38: /* IPMI Device Information */
+ dmi_save_ipmi_device(dm);
+ break;
+ case 41: /* Onboard Devices Extended Information */
+ dmi_save_extended_devices(dm);
+ }
+}
+
+static int __init print_filtered(char *buf, size_t len, const char *info)
+{
+ int c = 0;
+ const char *p;
+
+ if (!info)
+ return c;
+
+ for (p = info; *p; p++)
+ if (isprint(*p))
+ c += scnprintf(buf + c, len - c, "%c", *p);
+ else
+ c += scnprintf(buf + c, len - c, "\\x%02x", *p & 0xff);
+ return c;
+}
+
+static void __init dmi_format_ids(char *buf, size_t len)
+{
+ int c = 0;
+ const char *board; /* Board Name is optional */
+
+ c += print_filtered(buf + c, len - c,
+ dmi_get_system_info(DMI_SYS_VENDOR));
+ c += scnprintf(buf + c, len - c, " ");
+ c += print_filtered(buf + c, len - c,
+ dmi_get_system_info(DMI_PRODUCT_NAME));
+
+ board = dmi_get_system_info(DMI_BOARD_NAME);
+ if (board) {
+ c += scnprintf(buf + c, len - c, "/");
+ c += print_filtered(buf + c, len - c, board);
+ }
+ c += scnprintf(buf + c, len - c, ", BIOS ");
+ c += print_filtered(buf + c, len - c,
+ dmi_get_system_info(DMI_BIOS_VERSION));
+ c += scnprintf(buf + c, len - c, " ");
+ c += print_filtered(buf + c, len - c,
+ dmi_get_system_info(DMI_BIOS_DATE));
+}
+
+/*
+ * Check for DMI/SMBIOS headers in the system firmware image. Any
+ * SMBIOS header must start 16 bytes before the DMI header, so take a
+ * 32 byte buffer and check for DMI at offset 16 and SMBIOS at offset
+ * 0. If the DMI header is present, set dmi_ver accordingly (SMBIOS
+ * takes precedence) and return 0. Otherwise return 1.
+ */
+static int __init dmi_present(const u8 *buf)
+{
+ u32 smbios_ver;
+
+ if (memcmp(buf, "_SM_", 4) == 0 &&
+ buf[5] < 32 && dmi_checksum(buf, buf[5])) {
+ smbios_ver = get_unaligned_be16(buf + 6);
+
+ /* Some BIOS report weird SMBIOS version, fix that up */
+ switch (smbios_ver) {
+ case 0x021F:
+ case 0x0221:
+ pr_debug("SMBIOS version fixup(2.%d->2.%d)\n",
+ smbios_ver & 0xFF, 3);
+ smbios_ver = 0x0203;
+ break;
+ case 0x0233:
+ pr_debug("SMBIOS version fixup(2.%d->2.%d)\n", 51, 6);
+ smbios_ver = 0x0206;
+ break;
+ }
+ } else {
+ smbios_ver = 0;
+ }
+
+ buf += 16;
+
+ if (memcmp(buf, "_DMI_", 5) == 0 && dmi_checksum(buf, 15)) {
+ if (smbios_ver)
+ dmi_ver = smbios_ver;
+ else
+ dmi_ver = (buf[14] & 0xF0) << 4 | (buf[14] & 0x0F);
+ dmi_num = get_unaligned_le16(buf + 12);
+ dmi_len = get_unaligned_le16(buf + 6);
+ dmi_base = get_unaligned_le32(buf + 8);
+
+ if (dmi_walk_early(dmi_decode) == 0) {
+ if (smbios_ver) {
+ pr_info("SMBIOS %d.%d present.\n",
+ dmi_ver >> 8, dmi_ver & 0xFF);
+ } else {
+ pr_info("Legacy DMI %d.%d present.\n",
+ dmi_ver >> 8, dmi_ver & 0xFF);
+ }
+ dmi_ver <<= 8;
+ dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
+ printk(KERN_DEBUG "DMI: %s\n", dmi_ids_string);
+ return 0;
+ }
+ }
+
+ return 1;
+}
+
+/*
+ * Check for the SMBIOS 3.0 64-bit entry point signature. Unlike the legacy
+ * 32-bit entry point, there is no embedded DMI header (_DMI_) in here.
+ */
+static int __init dmi_smbios3_present(const u8 *buf)
+{
+ if (memcmp(buf, "_SM3_", 5) == 0 &&
+ buf[6] < 32 && dmi_checksum(buf, buf[6])) {
+ dmi_ver = get_unaligned_be32(buf + 6);
+ dmi_ver &= 0xFFFFFF;
+ dmi_num = 0; /* No longer specified */
+ dmi_len = get_unaligned_le32(buf + 12);
+ dmi_base = get_unaligned_le64(buf + 16);
+
+ if (dmi_walk_early(dmi_decode) == 0) {
+ pr_info("SMBIOS %d.%d.%d present.\n",
+ dmi_ver >> 16, (dmi_ver >> 8) & 0xFF,
+ dmi_ver & 0xFF);
+ dmi_format_ids(dmi_ids_string, sizeof(dmi_ids_string));
+ pr_debug("DMI: %s\n", dmi_ids_string);
+ return 0;
+ }
+ }
+ return 1;
+}
+
+void __init dmi_scan_machine(void)
+{
+ char __iomem *p, *q;
+ char buf[32];
+
+ if (efi_enabled(EFI_CONFIG_TABLES)) {
+ /*
+ * According to the DMTF SMBIOS reference spec v3.0.0, it is
+ * allowed to define both the 64-bit entry point (smbios3) and
+ * the 32-bit entry point (smbios), in which case they should
+ * either both point to the same SMBIOS structure table, or the
+ * table pointed to by the 64-bit entry point should contain a
+ * superset of the table contents pointed to by the 32-bit entry
+ * point (section 5.2)
+ * This implies that the 64-bit entry point should have
+ * precedence if it is defined and supported by the OS. If we
+ * have the 64-bit entry point, but fail to decode it, fall
+ * back to the legacy one (if available)
+ */
+ if (efi.smbios3 != EFI_INVALID_TABLE_ADDR) {
+ p = dmi_early_remap(efi.smbios3, 32);
+ if (p == NULL)
+ goto error;
+ memcpy_fromio(buf, p, 32);
+ dmi_early_unmap(p, 32);
+
+ if (!dmi_smbios3_present(buf)) {
+ dmi_available = 1;
+ goto out;
+ }
+ }
+ if (efi.smbios == EFI_INVALID_TABLE_ADDR)
+ goto error;
+
+ /* This is called as a core_initcall() because it isn't
+ * needed during early boot. This also means we can
+ * iounmap the space when we're done with it.
+ */
+ p = dmi_early_remap(efi.smbios, 32);
+ if (p == NULL)
+ goto error;
+ memcpy_fromio(buf, p, 32);
+ dmi_early_unmap(p, 32);
+
+ if (!dmi_present(buf)) {
+ dmi_available = 1;
+ goto out;
+ }
+ } else if (IS_ENABLED(CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK)) {
+ p = dmi_early_remap(0xF0000, 0x10000);
+ if (p == NULL)
+ goto error;
+
+ /*
+ * Iterate over all possible DMI header addresses q.
+ * Maintain the 32 bytes around q in buf. On the
+ * first iteration, substitute zero for the
+ * out-of-range bytes so there is no chance of falsely
+ * detecting an SMBIOS header.
+ */
+ memset(buf, 0, 16);
+ for (q = p; q < p + 0x10000; q += 16) {
+ memcpy_fromio(buf + 16, q, 16);
+ if (!dmi_smbios3_present(buf) || !dmi_present(buf)) {
+ dmi_available = 1;
+ dmi_early_unmap(p, 0x10000);
+ goto out;
+ }
+ memcpy(buf, buf + 16, 16);
+ }
+ dmi_early_unmap(p, 0x10000);
+ }
+ error:
+ pr_info("DMI not present or invalid.\n");
+ out:
+ dmi_initialized = 1;
+}
+
+/**
+ * dmi_set_dump_stack_arch_desc - set arch description for dump_stack()
+ *
+ * Invoke dump_stack_set_arch_desc() with DMI system information so that
+ * DMI identifiers are printed out on task dumps. Arch boot code should
+ * call this function after dmi_scan_machine() if it wants to print out DMI
+ * identifiers on task dumps.
+ */
+void __init dmi_set_dump_stack_arch_desc(void)
+{
+ dump_stack_set_arch_desc("%s", dmi_ids_string);
+}
+
+/**
+ * dmi_matches - check if dmi_system_id structure matches system DMI data
+ * @dmi: pointer to the dmi_system_id structure to check
+ */
+static bool dmi_matches(const struct dmi_system_id *dmi)
+{
+ int i;
+
+ WARN(!dmi_initialized, KERN_ERR "dmi check: not initialized yet.\n");
+
+ for (i = 0; i < ARRAY_SIZE(dmi->matches); i++) {
+ int s = dmi->matches[i].slot;
+ if (s == DMI_NONE)
+ break;
+ if (dmi_ident[s]) {
+ if (!dmi->matches[i].exact_match &&
+ strstr(dmi_ident[s], dmi->matches[i].substr))
+ continue;
+ else if (dmi->matches[i].exact_match &&
+ !strcmp(dmi_ident[s], dmi->matches[i].substr))
+ continue;
+ }
+
+ /* No match */
+ return false;
+ }
+ return true;
+}
+
+/**
+ * dmi_is_end_of_table - check for end-of-table marker
+ * @dmi: pointer to the dmi_system_id structure to check
+ */
+static bool dmi_is_end_of_table(const struct dmi_system_id *dmi)
+{
+ return dmi->matches[0].slot == DMI_NONE;
+}
+
+/**
+ * dmi_check_system - check system DMI data
+ * @list: array of dmi_system_id structures to match against
+ * All non-null elements of the list must match
+ * their slot's (field index's) data (i.e., each
+ * list string must be a substring of the specified
+ * DMI slot's string data) to be considered a
+ * successful match.
+ *
+ * Walk the blacklist table running matching functions until someone
+ * returns non zero or we hit the end. Callback function is called for
+ * each successful match. Returns the number of matches.
+ */
+int dmi_check_system(const struct dmi_system_id *list)
+{
+ int count = 0;
+ const struct dmi_system_id *d;
+
+ for (d = list; !dmi_is_end_of_table(d); d++)
+ if (dmi_matches(d)) {
+ count++;
+ if (d->callback && d->callback(d))
+ break;
+ }
+
+ return count;
+}
+EXPORT_SYMBOL(dmi_check_system);
+
+/**
+ * dmi_first_match - find dmi_system_id structure matching system DMI data
+ * @list: array of dmi_system_id structures to match against
+ * All non-null elements of the list must match
+ * their slot's (field index's) data (i.e., each
+ * list string must be a substring of the specified
+ * DMI slot's string data) to be considered a
+ * successful match.
+ *
+ * Walk the blacklist table until the first match is found. Return the
+ * pointer to the matching entry or NULL if there's no match.
+ */
+const struct dmi_system_id *dmi_first_match(const struct dmi_system_id *list)
+{
+ const struct dmi_system_id *d;
+
+ for (d = list; !dmi_is_end_of_table(d); d++)
+ if (dmi_matches(d))
+ return d;
+
+ return NULL;
+}
+EXPORT_SYMBOL(dmi_first_match);
+
+/**
+ * dmi_get_system_info - return DMI data value
+ * @field: data index (see enum dmi_field)
+ *
+ * Returns one DMI data value, can be used to perform
+ * complex DMI data checks.
+ */
+const char *dmi_get_system_info(int field)
+{
+ return dmi_ident[field];
+}
+EXPORT_SYMBOL(dmi_get_system_info);
+
+/**
+ * dmi_name_in_serial - Check if string is in the DMI product serial information
+ * @str: string to check for
+ */
+int dmi_name_in_serial(const char *str)
+{
+ int f = DMI_PRODUCT_SERIAL;
+ if (dmi_ident[f] && strstr(dmi_ident[f], str))
+ return 1;
+ return 0;
+}
+
+/**
+ * dmi_name_in_vendors - Check if string is in the DMI system or board vendor name
+ * @str: Case sensitive Name
+ */
+int dmi_name_in_vendors(const char *str)
+{
+ static int fields[] = { DMI_SYS_VENDOR, DMI_BOARD_VENDOR, DMI_NONE };
+ int i;
+ for (i = 0; fields[i] != DMI_NONE; i++) {
+ int f = fields[i];
+ if (dmi_ident[f] && strstr(dmi_ident[f], str))
+ return 1;
+ }
+ return 0;
+}
+EXPORT_SYMBOL(dmi_name_in_vendors);
+
+/**
+ * dmi_find_device - find onboard device by type/name
+ * @type: device type or %DMI_DEV_TYPE_ANY to match all device types
+ * @name: device name string or %NULL to match all
+ * @from: previous device found in search, or %NULL for new search.
+ *
+ * Iterates through the list of known onboard devices. If a device is
+ * found with a matching @vendor and @device, a pointer to its device
+ * structure is returned. Otherwise, %NULL is returned.
+ * A new search is initiated by passing %NULL as the @from argument.
+ * If @from is not %NULL, searches continue from next device.
+ */
+const struct dmi_device *dmi_find_device(int type, const char *name,
+ const struct dmi_device *from)
+{
+ const struct list_head *head = from ? &from->list : &dmi_devices;
+ struct list_head *d;
+
+ for (d = head->next; d != &dmi_devices; d = d->next) {
+ const struct dmi_device *dev =
+ list_entry(d, struct dmi_device, list);
+
+ if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
+ ((name == NULL) || (strcmp(dev->name, name) == 0)))
+ return dev;
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL(dmi_find_device);
+
+/**
+ * dmi_get_date - parse a DMI date
+ * @field: data index (see enum dmi_field)
+ * @yearp: optional out parameter for the year
+ * @monthp: optional out parameter for the month
+ * @dayp: optional out parameter for the day
+ *
+ * The date field is assumed to be in the form resembling
+ * [mm[/dd]]/yy[yy] and the result is stored in the out
+ * parameters any or all of which can be omitted.
+ *
+ * If the field doesn't exist, all out parameters are set to zero
+ * and false is returned. Otherwise, true is returned with any
+ * invalid part of date set to zero.
+ *
+ * On return, year, month and day are guaranteed to be in the
+ * range of [0,9999], [0,12] and [0,31] respectively.
+ */
+bool dmi_get_date(int field, int *yearp, int *monthp, int *dayp)
+{
+ int year = 0, month = 0, day = 0;
+ bool exists;
+ const char *s, *y;
+ char *e;
+
+ s = dmi_get_system_info(field);
+ exists = s;
+ if (!exists)
+ goto out;
+
+ /*
+ * Determine year first. We assume the date string resembles
+ * mm/dd/yy[yy] but the original code extracted only the year
+ * from the end. Keep the behavior in the spirit of no
+ * surprises.
+ */
+ y = strrchr(s, '/');
+ if (!y)
+ goto out;
+
+ y++;
+ year = simple_strtoul(y, &e, 10);
+ if (y != e && year < 100) { /* 2-digit year */
+ year += 1900;
+ if (year < 1996) /* no dates < spec 1.0 */
+ year += 100;
+ }
+ if (year > 9999) /* year should fit in %04d */
+ year = 0;
+
+ /* parse the mm and dd */
+ month = simple_strtoul(s, &e, 10);
+ if (s == e || *e != '/' || !month || month > 12) {
+ month = 0;
+ goto out;
+ }
+
+ s = e + 1;
+ day = simple_strtoul(s, &e, 10);
+ if (s == y || s == e || *e != '/' || day > 31)
+ day = 0;
+out:
+ if (yearp)
+ *yearp = year;
+ if (monthp)
+ *monthp = month;
+ if (dayp)
+ *dayp = day;
+ return exists;
+}
+EXPORT_SYMBOL(dmi_get_date);
+
+/**
+ * dmi_walk - Walk the DMI table and get called back for every record
+ * @decode: Callback function
+ * @private_data: Private data to be passed to the callback function
+ *
+ * Returns -1 when the DMI table can't be reached, 0 on success.
+ */
+int dmi_walk(void (*decode)(const struct dmi_header *, void *),
+ void *private_data)
+{
+ u8 *buf;
+
+ if (!dmi_available)
+ return -1;
+
+ buf = dmi_remap(dmi_base, dmi_len);
+ if (buf == NULL)
+ return -1;
+
+ dmi_table(buf, decode, private_data);
+
+ dmi_unmap(buf);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(dmi_walk);
+
+/**
+ * dmi_match - compare a string to the dmi field (if exists)
+ * @f: DMI field identifier
+ * @str: string to compare the DMI field to
+ *
+ * Returns true if the requested field equals to the str (including NULL).
+ */
+bool dmi_match(enum dmi_field f, const char *str)
+{
+ const char *info = dmi_get_system_info(f);
+
+ if (info == NULL || str == NULL)
+ return info == str;
+
+ return !strcmp(info, str);
+}
+EXPORT_SYMBOL_GPL(dmi_match);
+
+void dmi_memdev_name(u16 handle, const char **bank, const char **device)
+{
+ int n;
+
+ if (dmi_memdev == NULL)
+ return;
+
+ for (n = 0; n < dmi_memdev_nr; n++) {
+ if (handle == dmi_memdev[n].handle) {
+ *bank = dmi_memdev[n].bank;
+ *device = dmi_memdev[n].device;
+ break;
+ }
+ }
+}
+EXPORT_SYMBOL_GPL(dmi_memdev_name);