diff options
Diffstat (limited to 'drivers/firmware')
| -rw-r--r-- | drivers/firmware/dmi_scan.c | 79 |
1 files changed, 72 insertions, 7 deletions
diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c index 17afc51f3054..c5f7b4e9eb6c 100644 --- a/drivers/firmware/dmi_scan.c +++ b/drivers/firmware/dmi_scan.c @@ -93,6 +93,12 @@ static void dmi_table(u8 *buf, int len, int num, const struct dmi_header *dm = (const struct dmi_header *)data; /* + * 7.45 End-of-Table (Type 127) [SMBIOS reference spec v3.0.0] + */ + if (dm->type == DMI_ENTRY_END_OF_TABLE) + break; + + /* * 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 @@ -107,7 +113,7 @@ static void dmi_table(u8 *buf, int len, int num, } } -static u32 dmi_base; +static phys_addr_t dmi_base; static u16 dmi_len; static u16 dmi_num; @@ -467,7 +473,7 @@ static int __init dmi_present(const u8 *buf) if (memcmp(buf, "_SM_", 4) == 0 && buf[5] < 32 && dmi_checksum(buf, buf[5])) { - smbios_ver = (buf[6] << 8) + buf[7]; + smbios_ver = get_unaligned_be16(buf + 6); /* Some BIOS report weird SMBIOS version, fix that up */ switch (smbios_ver) { @@ -489,10 +495,9 @@ static int __init dmi_present(const u8 *buf) buf += 16; if (memcmp(buf, "_DMI_", 5) == 0 && dmi_checksum(buf, 15)) { - dmi_num = (buf[13] << 8) | buf[12]; - dmi_len = (buf[7] << 8) | buf[6]; - dmi_base = (buf[11] << 24) | (buf[10] << 16) | - (buf[9] << 8) | buf[8]; + 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) { @@ -514,12 +519,72 @@ static int __init dmi_present(const u8 *buf) 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_be16(buf + 7); + dmi_len = get_unaligned_le32(buf + 12); + dmi_base = get_unaligned_le64(buf + 16); + + /* + * The 64-bit SMBIOS 3.0 entry point no longer has a field + * containing the number of structures present in the table. + * Instead, it defines the table size as a maximum size, and + * relies on the end-of-table structure type (#127) to be used + * to signal the end of the table. + * So let's define dmi_num as an upper bound as well: each + * structure has a 4 byte header, so dmi_len / 4 is an upper + * bound for the number of structures in the table. + */ + dmi_num = dmi_len / 4; + + if (dmi_walk_early(dmi_decode) == 0) { + pr_info("SMBIOS %d.%d present.\n", + dmi_ver >> 8, 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; @@ -552,7 +617,7 @@ void __init dmi_scan_machine(void) memset(buf, 0, 16); for (q = p; q < p + 0x10000; q += 16) { memcpy_fromio(buf + 16, q, 16); - if (!dmi_present(buf)) { + if (!dmi_smbios3_present(buf) || !dmi_present(buf)) { dmi_available = 1; dmi_early_unmap(p, 0x10000); goto out; |