1 files changed, 47 insertions, 15 deletions

diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c
index 3714e3c03df6..fd3ae6290d71 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 +415,57 @@ 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)
+                                pr_info("SMBIOS %d.%d present.\n",
+                                       dmi_ver >> 8, dmi_ver & 0xFF);
+                        else {
+                                dmi_ver = (buf[14] & 0xF0) << 4 |
+                                           (buf[14] & 0x0F);
+                                pr_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:
+                        pr_debug("SMBIOS version fixup(2.%d->2.%d)\n",
+                               dmi_ver & 0xFF, 3);
+                        dmi_ver = 0x0203;
+                        break;
+                case 0x0233:
+                        pr_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 +483,7 @@ 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 +501,12 @@ 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);