From 096e65dca84828be7ca2b7da58209b22f16302e9 Mon Sep 17 00:00:00 2001 From: Zhenzhong Duan Date: Tue, 14 Aug 2012 13:22:44 +1000 Subject: [PATCH] drivers/firmware/dmi_scan.c: fetch dmi version from SMBIOS if it exists The right dmi version is in SMBIOS if it's zero in DMI region Signed-off-by: Zhenzhong Duan Cc: Feng Jin Cc: Jean Delvare Signed-off-by: Andrew Morton --- drivers/firmware/dmi_scan.c | 63 ++++++++++++++++++++++++++++--------- 1 file changed, 48 insertions(+), 15 deletions(-) diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c index 3714e3c03df6..111f3bab3a32 100644 --- a/drivers/firmware/dmi_scan.c +++ b/drivers/firmware/dmi_scan.c @@ -119,12 +119,12 @@ static int __init dmi_walk_early(void (*decode)(const struct dmi_header *, return 0; } -static int __init dmi_checksum(const u8 *buf) +static int __init dmi_checksum(const u8 *buf, u8 len) { u8 sum = 0; int a; - for (a = 0; a < 15; a++) + for (a = 0; a < len; a++) sum += buf[a]; return sum == 0; @@ -415,30 +415,58 @@ static int __init dmi_present(const char __iomem *p) u8 buf[15]; memcpy_fromio(buf, p, 15); - if ((memcmp(buf, "_DMI_", 5) == 0) && dmi_checksum(buf)) { + if (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 version 0.0 means that the real version is taken from - * the SMBIOS version, which we don't know at this point. - */ - dmi_ver = (buf[14] & 0xf0) << 4 | (buf[14] & 0x0f); - if (buf[14] != 0) - printk(KERN_INFO "DMI %d.%d present.\n", - buf[14] >> 4, buf[14] & 0xF); - else - printk(KERN_INFO "DMI present.\n"); if (dmi_walk_early(dmi_decode) == 0) { + if (dmi_ver) + printk(KERN_INFO "SMBIOS %d.%d present.\n", + dmi_ver >> 8, dmi_ver & 0xFF); + else { + dmi_ver = (buf[14] & 0xF0) << 4 | + (buf[14] & 0x0F); + printk(KERN_INFO "Legacy DMI %d.%d present.\n", + dmi_ver >> 8, dmi_ver & 0xFF); + } dmi_dump_ids(); return 0; } } + dmi_ver = 0; return 1; } +static int __init smbios_present(const char __iomem *p) +{ + u8 buf[32]; + int offset = 0; + + memcpy_fromio(buf, p, 32); + if ((buf[5] < 32) && dmi_checksum(buf, buf[5])) { + dmi_ver = (buf[6] << 8) + buf[7]; + + /* Some BIOS report weird SMBIOS version, fix that up */ + switch (dmi_ver) { + case 0x021F: + case 0x0221: + printk(KERN_DEBUG "SMBIOS version fixup(2.%d->2.%d)\n", + dmi_ver & 0xFF, 3); + dmi_ver = 0x0203; + break; + case 0x0233: + printk(KERN_DEBUG "SMBIOS version fixup(2.%d->2.%d)\n", + 51, 6); + dmi_ver = 0x0206; + break; + } + offset = 16; + } + return dmi_present(buf + offset); +} + void __init dmi_scan_machine(void) { char __iomem *p, *q; @@ -456,7 +484,7 @@ void __init dmi_scan_machine(void) if (p == NULL) goto error; - rc = dmi_present(p + 0x10); /* offset of _DMI_ string */ + rc = smbios_present(p); dmi_iounmap(p, 32); if (!rc) { dmi_available = 1; @@ -474,7 +502,12 @@ void __init dmi_scan_machine(void) goto error; for (q = p; q < p + 0x10000; q += 16) { - rc = dmi_present(q); + if (memcmp(q, "_SM_", 4) == 0 && q - p <= 0xFFE0) + rc = smbios_present(q); + else if (memcmp(q, "_DMI_", 5) == 0) + rc = dmi_present(q); + else + continue; if (!rc) { dmi_available = 1; dmi_iounmap(p, 0x10000); -- 2.39.2