Merge remote branch 'origin/master' into merge

Manual merge of arch/powerpc/kernel/smp.c and add missing scheduler_ipi()
call to arch/powerpc/platforms/cell/interrupt.c

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

9 files changed, 1202 insertions, 36 deletions

diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
index b3a25a55ba23..efba163595db 100644
--- a/drivers/firmware/Kconfig
+++ b/drivers/firmware/Kconfig
@@ -157,4 +157,6 @@ config SIGMA
           If unsure, say N here.  Drivers that need these helpers will select
           this option automatically.
 
+source "drivers/firmware/google/Kconfig"
+
 endmenu
diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile
index 00bb0b80a79f..47338c979126 100644
--- a/drivers/firmware/Makefile
+++ b/drivers/firmware/Makefile
@@ -13,3 +13,5 @@ obj-$(CONFIG_ISCSI_IBFT_FIND)	+= iscsi_ibft_find.o
 obj-$(CONFIG_ISCSI_IBFT)        += iscsi_ibft.o
 obj-$(CONFIG_FIRMWARE_MEMMAP)   += memmap.o
 obj-$(CONFIG_SIGMA)             += sigma.o
+
+obj-$(CONFIG_GOOGLE_FIRMWARE)   += google/
diff --git a/drivers/firmware/edd.c b/drivers/firmware/edd.c
index 96c25d93eed1..f1b7f659d3c9 100644
--- a/drivers/firmware/edd.c
+++ b/drivers/firmware/edd.c
@@ -531,8 +531,8 @@ static int
 edd_has_edd30(struct edd_device *edev)
 {
         struct edd_info *info;
-        int i, nonzero_path = 0;
-        char c;
+        int i;
+        u8 csum = 0;
 
         if (!edev)
                 return 0;
@@ -544,16 +544,16 @@ edd_has_edd30(struct edd_device *edev)
                 return 0;
         }
 
-        for (i = 30; i <= 73; i++) {
-                c = *(((uint8_t *) info) + i + 4);
-                if (c) {
-                        nonzero_path++;
-                        break;
-                }
-        }
-        if (!nonzero_path) {
+
+        /* We support only T13 spec */
+        if (info->params.device_path_info_length != 44)
+                return 0;
+
+        for (i = 30; i < info->params.device_path_info_length + 30; i++)
+                csum += *(((u8 *)&info->params) + i);
+
+        if (csum)
                 return 0;
-        }
 
         return 1;
 }
diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index ff0c373e3bbf..a2d2f1f0d4f3 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -677,8 +677,8 @@ create_efivars_bin_attributes(struct efivars *efivars)
 
         return 0;
 out_free:
-        kfree(efivars->new_var);
-        efivars->new_var = NULL;
+        kfree(efivars->del_var);
+        efivars->del_var = NULL;
         kfree(efivars->new_var);
         efivars->new_var = NULL;
         return error;
@@ -803,6 +803,8 @@ efivars_init(void)
         ops.set_variable = efi.set_variable;
         ops.get_next_variable = efi.get_next_variable;
         error = register_efivars(&__efivars, &ops, efi_kobj);
+        if (error)
+                goto err_put;
 
         /* Don't forget the systab entry */
         error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
@@ -810,18 +812,25 @@ efivars_init(void)
                 printk(KERN_ERR
                        "efivars: Sysfs attribute export failed with error %d.\n",
                        error);
-                unregister_efivars(&__efivars);
-                kobject_put(efi_kobj);
+                goto err_unregister;
         }
 
+        return 0;
+
+err_unregister:
+        unregister_efivars(&__efivars);
+err_put:
+        kobject_put(efi_kobj);
         return error;
 }
 
 static void __exit
 efivars_exit(void)
 {
-        unregister_efivars(&__efivars);
-        kobject_put(efi_kobj);
+        if (efi_enabled) {
+                unregister_efivars(&__efivars);
+                kobject_put(efi_kobj);
+        }
 }
 
 module_init(efivars_init);
diff --git a/drivers/firmware/google/Kconfig b/drivers/firmware/google/Kconfig
new file mode 100644
index 000000000000..87096b6ca5c9
--- /dev/null
+++ b/drivers/firmware/google/Kconfig
@@ -0,0 +1,31 @@
+config GOOGLE_FIRMWARE
+        bool "Google Firmware Drivers"
+        depends on X86
+        default n
+        help
+          These firmware drivers are used by Google's servers.  They are
+          only useful if you are working directly on one of their
+          proprietary servers.  If in doubt, say "N".
+
+menu "Google Firmware Drivers"
+        depends on GOOGLE_FIRMWARE
+
+config GOOGLE_SMI
+        tristate "SMI interface for Google platforms"
+        depends on ACPI && DMI
+        select EFI_VARS
+        help
+          Say Y here if you want to enable SMI callbacks for Google
+          platforms.  This provides an interface for writing to and
+          clearing the EFI event log and reading and writing NVRAM
+          variables.
+
+config GOOGLE_MEMCONSOLE
+        tristate "Firmware Memory Console"
+        depends on DMI
+        help
+          This option enables the kernel to search for a firmware log in
+          the EBDA on Google servers.  If found, this log is exported to
+          userland in the file /sys/firmware/log.
+
+endmenu
diff --git a/drivers/firmware/google/Makefile b/drivers/firmware/google/Makefile
new file mode 100644
index 000000000000..54a294e3cb61
--- /dev/null
+++ b/drivers/firmware/google/Makefile
@@ -0,0 +1,3 @@
+
+obj-$(CONFIG_GOOGLE_SMI)                += gsmi.o
+obj-$(CONFIG_GOOGLE_MEMCONSOLE)         += memconsole.o
diff --git a/drivers/firmware/google/gsmi.c b/drivers/firmware/google/gsmi.c
new file mode 100644
index 000000000000..fa7f0b3e81dd
--- /dev/null
+++ b/drivers/firmware/google/gsmi.c
@@ -0,0 +1,940 @@
+/*
+ * Copyright 2010 Google Inc. All Rights Reserved.
+ * Author: dlaurie@google.com (Duncan Laurie)
+ *
+ * Re-worked to expose sysfs APIs by mikew@google.com (Mike Waychison)
+ *
+ * EFI SMI interface for Google platforms
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/spinlock.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/ioctl.h>
+#include <linux/acpi.h>
+#include <linux/io.h>
+#include <linux/uaccess.h>
+#include <linux/dmi.h>
+#include <linux/kdebug.h>
+#include <linux/reboot.h>
+#include <linux/efi.h>
+
+#define GSMI_SHUTDOWN_CLEAN     0       /* Clean Shutdown */
+/* TODO(mikew@google.com): Tie in HARDLOCKUP_DETECTOR with NMIWDT */
+#define GSMI_SHUTDOWN_NMIWDT    1       /* NMI Watchdog */
+#define GSMI_SHUTDOWN_PANIC     2       /* Panic */
+#define GSMI_SHUTDOWN_OOPS      3       /* Oops */
+#define GSMI_SHUTDOWN_DIE       4       /* Die -- No longer meaningful */
+#define GSMI_SHUTDOWN_MCE       5       /* Machine Check */
+#define GSMI_SHUTDOWN_SOFTWDT   6       /* Software Watchdog */
+#define GSMI_SHUTDOWN_MBE       7       /* Uncorrected ECC */
+#define GSMI_SHUTDOWN_TRIPLE    8       /* Triple Fault */
+
+#define DRIVER_VERSION          "1.0"
+#define GSMI_GUID_SIZE          16
+#define GSMI_BUF_SIZE           1024
+#define GSMI_BUF_ALIGN          sizeof(u64)
+#define GSMI_CALLBACK           0xef
+
+/* SMI return codes */
+#define GSMI_SUCCESS            0x00
+#define GSMI_UNSUPPORTED2       0x03
+#define GSMI_LOG_FULL           0x0b
+#define GSMI_VAR_NOT_FOUND      0x0e
+#define GSMI_HANDSHAKE_SPIN     0x7d
+#define GSMI_HANDSHAKE_CF       0x7e
+#define GSMI_HANDSHAKE_NONE     0x7f
+#define GSMI_INVALID_PARAMETER  0x82
+#define GSMI_UNSUPPORTED        0x83
+#define GSMI_BUFFER_TOO_SMALL   0x85
+#define GSMI_NOT_READY          0x86
+#define GSMI_DEVICE_ERROR       0x87
+#define GSMI_NOT_FOUND          0x8e
+
+#define QUIRKY_BOARD_HASH 0x78a30a50
+
+/* Internally used commands passed to the firmware */
+#define GSMI_CMD_GET_NVRAM_VAR          0x01
+#define GSMI_CMD_GET_NEXT_VAR           0x02
+#define GSMI_CMD_SET_NVRAM_VAR          0x03
+#define GSMI_CMD_SET_EVENT_LOG          0x08
+#define GSMI_CMD_CLEAR_EVENT_LOG        0x09
+#define GSMI_CMD_CLEAR_CONFIG           0x20
+#define GSMI_CMD_HANDSHAKE_TYPE         0xC1
+
+/* Magic entry type for kernel events */
+#define GSMI_LOG_ENTRY_TYPE_KERNEL     0xDEAD
+
+/* SMI buffers must be in 32bit physical address space */
+struct gsmi_buf {
+        u8 *start;                      /* start of buffer */
+        size_t length;                  /* length of buffer */
+        dma_addr_t handle;              /* dma allocation handle */
+        u32 address;                    /* physical address of buffer */
+};
+
+struct gsmi_device {
+        struct platform_device *pdev;   /* platform device */
+        struct gsmi_buf *name_buf;      /* variable name buffer */
+        struct gsmi_buf *data_buf;      /* generic data buffer */
+        struct gsmi_buf *param_buf;     /* parameter buffer */
+        spinlock_t lock;                /* serialize access to SMIs */
+        u16 smi_cmd;                    /* SMI command port */
+        int handshake_type;             /* firmware handler interlock type */
+        struct dma_pool *dma_pool;      /* DMA buffer pool */
+} gsmi_dev;
+
+/* Packed structures for communicating with the firmware */
+struct gsmi_nvram_var_param {
+        efi_guid_t      guid;
+        u32             name_ptr;
+        u32             attributes;
+        u32             data_len;
+        u32             data_ptr;
+} __packed;
+
+struct gsmi_get_next_var_param {
+        u8      guid[GSMI_GUID_SIZE];
+        u32     name_ptr;
+        u32     name_len;
+} __packed;
+
+struct gsmi_set_eventlog_param {
+        u32     data_ptr;
+        u32     data_len;
+        u32     type;
+} __packed;
+
+/* Event log formats */
+struct gsmi_log_entry_type_1 {
+        u16     type;
+        u32     instance;
+} __packed;
+
+
+/*
+ * Some platforms don't have explicit SMI handshake
+ * and need to wait for SMI to complete.
+ */
+#define GSMI_DEFAULT_SPINCOUNT  0x10000
+static unsigned int spincount = GSMI_DEFAULT_SPINCOUNT;
+module_param(spincount, uint, 0600);
+MODULE_PARM_DESC(spincount,
+        "The number of loop iterations to use when using the spin handshake.");
+
+static struct gsmi_buf *gsmi_buf_alloc(void)
+{
+        struct gsmi_buf *smibuf;
+
+        smibuf = kzalloc(sizeof(*smibuf), GFP_KERNEL);
+        if (!smibuf) {
+                printk(KERN_ERR "gsmi: out of memory\n");
+                return NULL;
+        }
+
+        /* allocate buffer in 32bit address space */
+        smibuf->start = dma_pool_alloc(gsmi_dev.dma_pool, GFP_KERNEL,
+                                       &smibuf->handle);
+        if (!smibuf->start) {
+                printk(KERN_ERR "gsmi: failed to allocate name buffer\n");
+                kfree(smibuf);
+                return NULL;
+        }
+
+        /* fill in the buffer handle */
+        smibuf->length = GSMI_BUF_SIZE;
+        smibuf->address = (u32)virt_to_phys(smibuf->start);
+
+        return smibuf;
+}
+
+static void gsmi_buf_free(struct gsmi_buf *smibuf)
+{
+        if (smibuf) {
+                if (smibuf->start)
+                        dma_pool_free(gsmi_dev.dma_pool, smibuf->start,
+                                      smibuf->handle);
+                kfree(smibuf);
+        }
+}
+
+/*
+ * Make a call to gsmi func(sub).  GSMI error codes are translated to
+ * in-kernel errnos (0 on success, -ERRNO on error).
+ */
+static int gsmi_exec(u8 func, u8 sub)
+{
+        u16 cmd = (sub << 8) | func;
+        u16 result = 0;
+        int rc = 0;
+
+        /*
+         * AH  : Subfunction number
+         * AL  : Function number
+         * EBX : Parameter block address
+         * DX  : SMI command port
+         *
+         * Three protocols here. See also the comment in gsmi_init().
+         */
+        if (gsmi_dev.handshake_type == GSMI_HANDSHAKE_CF) {
+                /*
+                 * If handshake_type == HANDSHAKE_CF then set CF on the
+                 * way in and wait for the handler to clear it; this avoids
+                 * corrupting register state on those chipsets which have
+                 * a delay between writing the SMI trigger register and
+                 * entering SMM.
+                 */
+                asm volatile (
+                        "stc\n"
+                        "outb %%al, %%dx\n"
+                "1:      jc 1b\n"
+                        : "=a" (result)
+                        : "0" (cmd),
+                          "d" (gsmi_dev.smi_cmd),
+                          "b" (gsmi_dev.param_buf->address)
+                        : "memory", "cc"
+                );
+        } else if (gsmi_dev.handshake_type == GSMI_HANDSHAKE_SPIN) {
+                /*
+                 * If handshake_type == HANDSHAKE_SPIN we spin a
+                 * hundred-ish usecs to ensure the SMI has triggered.
+                 */
+                asm volatile (
+                        "outb %%al, %%dx\n"
+                "1:      loop 1b\n"
+                        : "=a" (result)
+                        : "0" (cmd),
+                          "d" (gsmi_dev.smi_cmd),
+                          "b" (gsmi_dev.param_buf->address),
+                          "c" (spincount)
+                        : "memory", "cc"
+                );
+        } else {
+                /*
+                 * If handshake_type == HANDSHAKE_NONE we do nothing;
+                 * either we don't need to or it's legacy firmware that
+                 * doesn't understand the CF protocol.
+                 */
+                asm volatile (
+                        "outb %%al, %%dx\n\t"
+                        : "=a" (result)
+                        : "0" (cmd),
+                          "d" (gsmi_dev.smi_cmd),
+                          "b" (gsmi_dev.param_buf->address)
+                        : "memory", "cc"
+                );
+        }
+
+        /* check return code from SMI handler */
+        switch (result) {
+        case GSMI_SUCCESS:
+                break;
+        case GSMI_VAR_NOT_FOUND:
+                /* not really an error, but let the caller know */
+                rc = 1;
+                break;
+        case GSMI_INVALID_PARAMETER:
+                printk(KERN_ERR "gsmi: exec 0x%04x: Invalid parameter\n", cmd);
+                rc = -EINVAL;
+                break;
+        case GSMI_BUFFER_TOO_SMALL:
+                printk(KERN_ERR "gsmi: exec 0x%04x: Buffer too small\n", cmd);
+                rc = -ENOMEM;
+                break;
+        case GSMI_UNSUPPORTED:
+        case GSMI_UNSUPPORTED2:
+                if (sub != GSMI_CMD_HANDSHAKE_TYPE)
+                        printk(KERN_ERR "gsmi: exec 0x%04x: Not supported\n",
+                               cmd);
+                rc = -ENOSYS;
+                break;
+        case GSMI_NOT_READY:
+                printk(KERN_ERR "gsmi: exec 0x%04x: Not ready\n", cmd);
+                rc = -EBUSY;
+                break;
+        case GSMI_DEVICE_ERROR:
+                printk(KERN_ERR "gsmi: exec 0x%04x: Device error\n", cmd);
+                rc = -EFAULT;
+                break;
+        case GSMI_NOT_FOUND:
+                printk(KERN_ERR "gsmi: exec 0x%04x: Data not found\n", cmd);
+                rc = -ENOENT;
+                break;
+        case GSMI_LOG_FULL:
+                printk(KERN_ERR "gsmi: exec 0x%04x: Log full\n", cmd);
+                rc = -ENOSPC;
+                break;
+        case GSMI_HANDSHAKE_CF:
+        case GSMI_HANDSHAKE_SPIN:
+        case GSMI_HANDSHAKE_NONE:
+                rc = result;
+                break;
+        default:
+                printk(KERN_ERR "gsmi: exec 0x%04x: Unknown error 0x%04x\n",
+                       cmd, result);
+                rc = -ENXIO;
+        }
+
+        return rc;
+}
+
+/* Return the number of unicode characters in data */
+static size_t
+utf16_strlen(efi_char16_t *data, unsigned long maxlength)
+{
+        unsigned long length = 0;
+
+        while (*data++ != 0 && length < maxlength)
+                length++;
+        return length;
+}
+
+static efi_status_t gsmi_get_variable(efi_char16_t *name,
+                                      efi_guid_t *vendor, u32 *attr,
+                                      unsigned long *data_size,
+                                      void *data)
+{
+        struct gsmi_nvram_var_param param = {
+                .name_ptr = gsmi_dev.name_buf->address,
+                .data_ptr = gsmi_dev.data_buf->address,
+                .data_len = (u32)*data_size,
+        };
+        efi_status_t ret = EFI_SUCCESS;
+        unsigned long flags;
+        size_t name_len = utf16_strlen(name, GSMI_BUF_SIZE / 2);
+        int rc;
+
+        if (name_len >= GSMI_BUF_SIZE / 2)
+                return EFI_BAD_BUFFER_SIZE;
+
+        spin_lock_irqsave(&gsmi_dev.lock, flags);
+
+        /* Vendor guid */
+        memcpy(&param.guid, vendor, sizeof(param.guid));
+
+        /* variable name, already in UTF-16 */
+        memset(gsmi_dev.name_buf->start, 0, gsmi_dev.name_buf->length);
+        memcpy(gsmi_dev.name_buf->start, name, name_len * 2);
+
+        /* data pointer */
+        memset(gsmi_dev.data_buf->start, 0, gsmi_dev.data_buf->length);
+
+        /* parameter buffer */
+        memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);
+        memcpy(gsmi_dev.param_buf->start, &param, sizeof(param));
+
+        rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_GET_NVRAM_VAR);
+        if (rc < 0) {
+                printk(KERN_ERR "gsmi: Get Variable failed\n");
+                ret = EFI_LOAD_ERROR;
+        } else if (rc == 1) {
+                /* variable was not found */
+                ret = EFI_NOT_FOUND;
+        } else {
+                /* Get the arguments back */
+                memcpy(&param, gsmi_dev.param_buf->start, sizeof(param));
+
+                /* The size reported is the min of all of our buffers */
+                *data_size = min(*data_size, gsmi_dev.data_buf->length);
+                *data_size = min_t(unsigned long, *data_size, param.data_len);
+
+                /* Copy data back to return buffer. */
+                memcpy(data, gsmi_dev.data_buf->start, *data_size);
+
+                /* All variables are have the following attributes */
+                *attr = EFI_VARIABLE_NON_VOLATILE |
+                        EFI_VARIABLE_BOOTSERVICE_ACCESS |
+                        EFI_VARIABLE_RUNTIME_ACCESS;
+        }
+
+        spin_unlock_irqrestore(&gsmi_dev.lock, flags);
+
+        return ret;
+}
+
+static efi_status_t gsmi_get_next_variable(unsigned long *name_size,
+                                           efi_char16_t *name,
+                                           efi_guid_t *vendor)
+{
+        struct gsmi_get_next_var_param param = {
+                .name_ptr = gsmi_dev.name_buf->address,
+                .name_len = gsmi_dev.name_buf->length,
+        };
+        efi_status_t ret = EFI_SUCCESS;
+        int rc;
+        unsigned long flags;
+
+        /* For the moment, only support buffers that exactly match in size */
+        if (*name_size != GSMI_BUF_SIZE)
+                return EFI_BAD_BUFFER_SIZE;
+
+        /* Let's make sure the thing is at least null-terminated */
+        if (utf16_strlen(name, GSMI_BUF_SIZE / 2) == GSMI_BUF_SIZE / 2)
+                return EFI_INVALID_PARAMETER;
+
+        spin_lock_irqsave(&gsmi_dev.lock, flags);
+
+        /* guid */
+        memcpy(&param.guid, vendor, sizeof(param.guid));
+
+        /* variable name, already in UTF-16 */
+        memcpy(gsmi_dev.name_buf->start, name, *name_size);
+
+        /* parameter buffer */
+        memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);
+        memcpy(gsmi_dev.param_buf->start, &param, sizeof(param));
+
+        rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_GET_NEXT_VAR);
+        if (rc < 0) {
+                printk(KERN_ERR "gsmi: Get Next Variable Name failed\n");
+                ret = EFI_LOAD_ERROR;
+        } else if (rc == 1) {
+                /* variable not found -- end of list */
+                ret = EFI_NOT_FOUND;
+        } else {
+                /* copy variable data back to return buffer */
+                memcpy(&param, gsmi_dev.param_buf->start, sizeof(param));
+
+                /* Copy the name back */
+                memcpy(name, gsmi_dev.name_buf->start, GSMI_BUF_SIZE);
+                *name_size = utf16_strlen(name, GSMI_BUF_SIZE / 2) * 2;
+
+                /* copy guid to return buffer */
+                memcpy(vendor, &param.guid, sizeof(param.guid));
+                ret = EFI_SUCCESS;
+        }
+
+        spin_unlock_irqrestore(&gsmi_dev.lock, flags);
+
+        return ret;
+}
+
+static efi_status_t gsmi_set_variable(efi_char16_t *name,
+                                      efi_guid_t *vendor,
+                                      unsigned long attr,
+                                      unsigned long data_size,
+                                      void *data)
+{
+        struct gsmi_nvram_var_param param = {
+                .name_ptr = gsmi_dev.name_buf->address,
+                .data_ptr = gsmi_dev.data_buf->address,
+                .data_len = (u32)data_size,
+                .attributes = EFI_VARIABLE_NON_VOLATILE |
+                              EFI_VARIABLE_BOOTSERVICE_ACCESS |
+                              EFI_VARIABLE_RUNTIME_ACCESS,
+        };
+        size_t name_len = utf16_strlen(name, GSMI_BUF_SIZE / 2);
+        efi_status_t ret = EFI_SUCCESS;
+        int rc;
+        unsigned long flags;
+
+        if (name_len >= GSMI_BUF_SIZE / 2)
+                return EFI_BAD_BUFFER_SIZE;
+
+        spin_lock_irqsave(&gsmi_dev.lock, flags);
+
+        /* guid */
+        memcpy(&param.guid, vendor, sizeof(param.guid));
+
+        /* variable name, already in UTF-16 */
+        memset(gsmi_dev.name_buf->start, 0, gsmi_dev.name_buf->length);
+        memcpy(gsmi_dev.name_buf->start, name, name_len * 2);
+
+        /* data pointer */
+        memset(gsmi_dev.data_buf->start, 0, gsmi_dev.data_buf->length);
+        memcpy(gsmi_dev.data_buf->start, data, data_size);
+
+        /* parameter buffer */
+        memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);
+        memcpy(gsmi_dev.param_buf->start, &param, sizeof(param));
+
+        rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_SET_NVRAM_VAR);
+        if (rc < 0) {
+                printk(KERN_ERR "gsmi: Set Variable failed\n");
+                ret = EFI_INVALID_PARAMETER;
+        }
+
+        spin_unlock_irqrestore(&gsmi_dev.lock, flags);
+
+        return ret;
+}
+
+static const struct efivar_operations efivar_ops = {
+        .get_variable = gsmi_get_variable,
+        .set_variable = gsmi_set_variable,
+        .get_next_variable = gsmi_get_next_variable,
+};
+
+static ssize_t eventlog_write(struct file *filp, struct kobject *kobj,
+                               struct bin_attribute *bin_attr,
+                               char *buf, loff_t pos, size_t count)
+{
+        struct gsmi_set_eventlog_param param = {
+                .data_ptr = gsmi_dev.data_buf->address,
+        };
+        int rc = 0;
+        unsigned long flags;
+
+        /* Pull the type out */
+        if (count < sizeof(u32))
+                return -EINVAL;
+        param.type = *(u32 *)buf;
+        count -= sizeof(u32);
+        buf += sizeof(u32);
+
+        /* The remaining buffer is the data payload */
+        if (count > gsmi_dev.data_buf->length)
+                return -EINVAL;
+        param.data_len = count - sizeof(u32);
+
+        spin_lock_irqsave(&gsmi_dev.lock, flags);
+
+        /* data pointer */
+        memset(gsmi_dev.data_buf->start, 0, gsmi_dev.data_buf->length);
+        memcpy(gsmi_dev.data_buf->start, buf, param.data_len);
+
+        /* parameter buffer */
+        memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);
+        memcpy(gsmi_dev.param_buf->start, &param, sizeof(param));
+
+        rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_SET_EVENT_LOG);
+        if (rc < 0)
+                printk(KERN_ERR "gsmi: Set Event Log failed\n");
+
+        spin_unlock_irqrestore(&gsmi_dev.lock, flags);
+
+        return rc;
+
+}
+
+static struct bin_attribute eventlog_bin_attr = {
+        .attr = {.name = "append_to_eventlog", .mode = 0200},
+        .write = eventlog_write,
+};
+
+static ssize_t gsmi_clear_eventlog_store(struct kobject *kobj,
+                                         struct kobj_attribute *attr,
+                                         const char *buf, size_t count)
+{
+        int rc;
+        unsigned long flags;
+        unsigned long val;
+        struct {
+                u32 percentage;
+                u32 data_type;
+        } param;
+
+        rc = strict_strtoul(buf, 0, &val);
+        if (rc)
+                return rc;
+
+        /*
+         * Value entered is a percentage, 0 through 100, anything else
+         * is invalid.
+         */
+        if (val > 100)
+                return -EINVAL;
+
+        /* data_type here selects the smbios event log. */
+        param.percentage = val;
+        param.data_type = 0;
+
+        spin_lock_irqsave(&gsmi_dev.lock, flags);
+
+        /* parameter buffer */
+        memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);
+        memcpy(gsmi_dev.param_buf->start, &param, sizeof(param));
+
+        rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_CLEAR_EVENT_LOG);
+
+        spin_unlock_irqrestore(&gsmi_dev.lock, flags);
+
+        if (rc)
+                return rc;
+        return count;
+}
+
+static struct kobj_attribute gsmi_clear_eventlog_attr = {
+        .attr = {.name = "clear_eventlog", .mode = 0200},
+        .store = gsmi_clear_eventlog_store,
+};
+
+static ssize_t gsmi_clear_config_store(struct kobject *kobj,
+                                       struct kobj_attribute *attr,
+                                       const char *buf, size_t count)
+{
+        int rc;
+        unsigned long flags;
+
+        spin_lock_irqsave(&gsmi_dev.lock, flags);
+
+        /* clear parameter buffer */
+        memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);
+
+        rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_CLEAR_CONFIG);
+
+        spin_unlock_irqrestore(&gsmi_dev.lock, flags);
+
+        if (rc)
+                return rc;
+        return count;
+}
+
+static struct kobj_attribute gsmi_clear_config_attr = {
+        .attr = {.name = "clear_config", .mode = 0200},
+        .store = gsmi_clear_config_store,
+};
+
+static const struct attribute *gsmi_attrs[] = {
+        &gsmi_clear_config_attr.attr,
+        &gsmi_clear_eventlog_attr.attr,
+        NULL,
+};
+
+static int gsmi_shutdown_reason(int reason)
+{
+        struct gsmi_log_entry_type_1 entry = {
+                .type     = GSMI_LOG_ENTRY_TYPE_KERNEL,
+                .instance = reason,
+        };
+        struct gsmi_set_eventlog_param param = {
+                .data_len = sizeof(entry),
+                .type     = 1,
+        };
+        static int saved_reason;
+        int rc = 0;
+        unsigned long flags;
+
+        /* avoid duplicate entries in the log */
+        if (saved_reason & (1 << reason))
+                return 0;
+
+        spin_lock_irqsave(&gsmi_dev.lock, flags);
+
+        saved_reason |= (1 << reason);
+
+        /* data pointer */
+        memset(gsmi_dev.data_buf->start, 0, gsmi_dev.data_buf->length);
+        memcpy(gsmi_dev.data_buf->start, &entry, sizeof(entry));
+
+        /* parameter buffer */
+        param.data_ptr = gsmi_dev.data_buf->address;
+        memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);
+        memcpy(gsmi_dev.param_buf->start, &param, sizeof(param));
+
+        rc = gsmi_exec(GSMI_CALLBACK, GSMI_CMD_SET_EVENT_LOG);
+
+        spin_unlock_irqrestore(&gsmi_dev.lock, flags);
+
+        if (rc < 0)
+                printk(KERN_ERR "gsmi: Log Shutdown Reason failed\n");
+        else
+                printk(KERN_EMERG "gsmi: Log Shutdown Reason 0x%02x\n",
+                       reason);
+
+        return rc;
+}
+
+static int gsmi_reboot_callback(struct notifier_block *nb,
+                                unsigned long reason, void *arg)
+{
+        gsmi_shutdown_reason(GSMI_SHUTDOWN_CLEAN);
+        return NOTIFY_DONE;
+}
+
+static struct notifier_block gsmi_reboot_notifier = {
+        .notifier_call = gsmi_reboot_callback
+};
+
+static int gsmi_die_callback(struct notifier_block *nb,
+                             unsigned long reason, void *arg)
+{
+        if (reason == DIE_OOPS)
+                gsmi_shutdown_reason(GSMI_SHUTDOWN_OOPS);
+        return NOTIFY_DONE;
+}
+
+static struct notifier_block gsmi_die_notifier = {
+        .notifier_call = gsmi_die_callback
+};
+
+static int gsmi_panic_callback(struct notifier_block *nb,
+                               unsigned long reason, void *arg)
+{
+        gsmi_shutdown_reason(GSMI_SHUTDOWN_PANIC);
+        return NOTIFY_DONE;
+}
+
+static struct notifier_block gsmi_panic_notifier = {
+        .notifier_call = gsmi_panic_callback,
+};
+
+/*
+ * This hash function was blatantly copied from include/linux/hash.h.
+ * It is used by this driver to obfuscate a board name that requires a
+ * quirk within this driver.
+ *
+ * Please do not remove this copy of the function as any changes to the
+ * global utility hash_64() function would break this driver's ability
+ * to identify a board and provide the appropriate quirk -- mikew@google.com
+ */
+static u64 __init local_hash_64(u64 val, unsigned bits)
+{
+        u64 hash = val;
+
+        /*  Sigh, gcc can't optimise this alone like it does for 32 bits. */
+        u64 n = hash;
+        n <<= 18;
+        hash -= n;
+        n <<= 33;
+        hash -= n;
+        n <<= 3;
+        hash += n;
+        n <<= 3;
+        hash -= n;
+        n <<= 4;
+        hash += n;
+        n <<= 2;
+        hash += n;
+
+        /* High bits are more random, so use them. */
+        return hash >> (64 - bits);
+}
+
+static u32 __init hash_oem_table_id(char s[8])
+{
+        u64 input;
+        memcpy(&input, s, 8);
+        return local_hash_64(input, 32);
+}
+
+static struct dmi_system_id gsmi_dmi_table[] __initdata = {
+        {
+                .ident = "Google Board",
+                .matches = {
+                        DMI_MATCH(DMI_BOARD_VENDOR, "Google, Inc."),
+                },
+        },
+        {}
+};
+MODULE_DEVICE_TABLE(dmi, gsmi_dmi_table);
+
+static __init int gsmi_system_valid(void)
+{
+        u32 hash;
+
+        if (!dmi_check_system(gsmi_dmi_table))
+                return -ENODEV;
+
+        /*
+         * Only newer firmware supports the gsmi interface.  All older
+         * firmware that didn't support this interface used to plug the
+         * table name in the first four bytes of the oem_table_id field.
+         * Newer firmware doesn't do that though, so use that as the
+         * discriminant factor.  We have to do this in order to
+         * whitewash our board names out of the public driver.
+         */
+        if (!strncmp(acpi_gbl_FADT.header.oem_table_id, "FACP", 4)) {
+                printk(KERN_INFO "gsmi: Board is too old\n");
+                return -ENODEV;
+        }
+
+        /* Disable on board with 1.0 BIOS due to Google bug 2602657 */
+        hash = hash_oem_table_id(acpi_gbl_FADT.header.oem_table_id);
+        if (hash == QUIRKY_BOARD_HASH) {
+                const char *bios_ver = dmi_get_system_info(DMI_BIOS_VERSION);
+                if (strncmp(bios_ver, "1.0", 3) == 0) {
+                        pr_info("gsmi: disabled on this board's BIOS %s\n",
+                                bios_ver);
+                        return -ENODEV;
+                }
+        }
+
+        /* check for valid SMI command port in ACPI FADT */
+        if (acpi_gbl_FADT.smi_command == 0) {
+                pr_info("gsmi: missing smi_command\n");
+                return -ENODEV;
+        }
+
+        /* Found */
+        return 0;
+}
+
+static struct kobject *gsmi_kobj;
+static struct efivars efivars;
+
+static __init int gsmi_init(void)
+{
+        unsigned long flags;
+        int ret;
+
+        ret = gsmi_system_valid();
+        if (ret)
+                return ret;
+
+        gsmi_dev.smi_cmd = acpi_gbl_FADT.smi_command;
+
+        /* register device */
+        gsmi_dev.pdev = platform_device_register_simple("gsmi", -1, NULL, 0);
+        if (IS_ERR(gsmi_dev.pdev)) {
+                printk(KERN_ERR "gsmi: unable to register platform device\n");
+                return PTR_ERR(gsmi_dev.pdev);
+        }
+
+        /* SMI access needs to be serialized */
+        spin_lock_init(&gsmi_dev.lock);
+
+        /* SMI callbacks require 32bit addresses */
+        gsmi_dev.pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+        gsmi_dev.pdev->dev.dma_mask =
+                &gsmi_dev.pdev->dev.coherent_dma_mask;
+        ret = -ENOMEM;
+        gsmi_dev.dma_pool = dma_pool_create("gsmi", &gsmi_dev.pdev->dev,
+                                             GSMI_BUF_SIZE, GSMI_BUF_ALIGN, 0);
+        if (!gsmi_dev.dma_pool)
+                goto out_err;
+
+        /*
+         * pre-allocate buffers because sometimes we are called when
+         * this is not feasible: oops, panic, die, mce, etc
+         */
+        gsmi_dev.name_buf = gsmi_buf_alloc();
+        if (!gsmi_dev.name_buf) {
+                printk(KERN_ERR "gsmi: failed to allocate name buffer\n");
+                goto out_err;
+        }
+
+        gsmi_dev.data_buf = gsmi_buf_alloc();
+        if (!gsmi_dev.data_buf) {
+                printk(KERN_ERR "gsmi: failed to allocate data buffer\n");
+                goto out_err;
+        }
+
+        gsmi_dev.param_buf = gsmi_buf_alloc();
+        if (!gsmi_dev.param_buf) {
+                printk(KERN_ERR "gsmi: failed to allocate param buffer\n");
+                goto out_err;
+        }
+
+        /*
+         * Determine type of handshake used to serialize the SMI
+         * entry. See also gsmi_exec().
+         *
+         * There's a "behavior" present on some chipsets where writing the
+         * SMI trigger register in the southbridge doesn't result in an
+         * immediate SMI. Rather, the processor can execute "a few" more
+         * instructions before the SMI takes effect. To ensure synchronous
+         * behavior, implement a handshake between the kernel driver and the
+         * firmware handler to spin until released. This ioctl determines
+         * the type of handshake.
+         *
+         * NONE: The firmware handler does not implement any
+         * handshake. Either it doesn't need to, or it's legacy firmware
+         * that doesn't know it needs to and never will.
+         *
+         * CF: The firmware handler will clear the CF in the saved
+         * state before returning. The driver may set the CF and test for
+         * it to clear before proceeding.
+         *
+         * SPIN: The firmware handler does not implement any handshake
+         * but the driver should spin for a hundred or so microseconds
+         * to ensure the SMI has triggered.
+         *
+         * Finally, the handler will return -ENOSYS if
+         * GSMI_CMD_HANDSHAKE_TYPE is unimplemented, which implies
+         * HANDSHAKE_NONE.
+         */
+        spin_lock_irqsave(&gsmi_dev.lock, flags);
+        gsmi_dev.handshake_type = GSMI_HANDSHAKE_SPIN;
+        gsmi_dev.handshake_type =
+            gsmi_exec(GSMI_CALLBACK, GSMI_CMD_HANDSHAKE_TYPE);
+        if (gsmi_dev.handshake_type == -ENOSYS)
+                gsmi_dev.handshake_type = GSMI_HANDSHAKE_NONE;
+        spin_unlock_irqrestore(&gsmi_dev.lock, flags);
+
+        /* Remove and clean up gsmi if the handshake could not complete. */
+        if (gsmi_dev.handshake_type == -ENXIO) {
+                printk(KERN_INFO "gsmi version " DRIVER_VERSION
+                       " failed to load\n");
+                ret = -ENODEV;
+                goto out_err;
+        }
+
+        printk(KERN_INFO "gsmi version " DRIVER_VERSION " loaded\n");
+
+        /* Register in the firmware directory */
+        ret = -ENOMEM;
+        gsmi_kobj = kobject_create_and_add("gsmi", firmware_kobj);
+        if (!gsmi_kobj) {
+                printk(KERN_INFO "gsmi: Failed to create firmware kobj\n");
+                goto out_err;
+        }
+
+        /* Setup eventlog access */
+        ret = sysfs_create_bin_file(gsmi_kobj, &eventlog_bin_attr);
+        if (ret) {
+                printk(KERN_INFO "gsmi: Failed to setup eventlog");
+                goto out_err;
+        }
+
+        /* Other attributes */
+        ret = sysfs_create_files(gsmi_kobj, gsmi_attrs);
+        if (ret) {
+                printk(KERN_INFO "gsmi: Failed to add attrs");
+                goto out_err;
+        }
+
+        if (register_efivars(&efivars, &efivar_ops, gsmi_kobj)) {
+                printk(KERN_INFO "gsmi: Failed to register efivars\n");
+                goto out_err;
+        }
+
+        register_reboot_notifier(&gsmi_reboot_notifier);
+        register_die_notifier(&gsmi_die_notifier);
+        atomic_notifier_chain_register(&panic_notifier_list,
+                                       &gsmi_panic_notifier);
+
+        return 0;
+
+ out_err:
+        kobject_put(gsmi_kobj);
+        gsmi_buf_free(gsmi_dev.param_buf);
+        gsmi_buf_free(gsmi_dev.data_buf);
+        gsmi_buf_free(gsmi_dev.name_buf);
+        if (gsmi_dev.dma_pool)
+                dma_pool_destroy(gsmi_dev.dma_pool);
+        platform_device_unregister(gsmi_dev.pdev);
+        pr_info("gsmi: failed to load: %d\n", ret);
+        return ret;
+}
+
+static void __exit gsmi_exit(void)
+{
+        unregister_reboot_notifier(&gsmi_reboot_notifier);
+        unregister_die_notifier(&gsmi_die_notifier);
+        atomic_notifier_chain_unregister(&panic_notifier_list,
+                                         &gsmi_panic_notifier);
+        unregister_efivars(&efivars);
+
+        kobject_put(gsmi_kobj);
+        gsmi_buf_free(gsmi_dev.param_buf);
+        gsmi_buf_free(gsmi_dev.data_buf);
+        gsmi_buf_free(gsmi_dev.name_buf);
+        dma_pool_destroy(gsmi_dev.dma_pool);
+        platform_device_unregister(gsmi_dev.pdev);
+}
+
+module_init(gsmi_init);
+module_exit(gsmi_exit);
+
+MODULE_AUTHOR("Google, Inc.");
+MODULE_LICENSE("GPL");
diff --git a/drivers/firmware/google/memconsole.c b/drivers/firmware/google/memconsole.c
new file mode 100644
index 000000000000..2a90ba613613
--- /dev/null
+++ b/drivers/firmware/google/memconsole.c
@@ -0,0 +1,166 @@
+/*
+ * memconsole.c
+ *
+ * Infrastructure for importing the BIOS memory based console
+ * into the kernel log ringbuffer.
+ *
+ * Copyright 2010 Google Inc. All rights reserved.
+ */
+
+#include <linux/ctype.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include <linux/kobject.h>
+#include <linux/module.h>
+#include <linux/dmi.h>
+#include <asm/bios_ebda.h>
+
+#define BIOS_MEMCONSOLE_V1_MAGIC        0xDEADBABE
+#define BIOS_MEMCONSOLE_V2_MAGIC        (('M')|('C'<<8)|('O'<<16)|('N'<<24))
+
+struct biosmemcon_ebda {
+        u32 signature;
+        union {
+                struct {
+                        u8  enabled;
+                        u32 buffer_addr;
+                        u16 start;
+                        u16 end;
+                        u16 num_chars;
+                        u8  wrapped;
+                } __packed v1;
+                struct {
+                        u32 buffer_addr;
+                        /* Misdocumented as number of pages! */
+                        u16 num_bytes;
+                        u16 start;
+                        u16 end;
+                } __packed v2;
+        };
+} __packed;
+
+static char *memconsole_baseaddr;
+static size_t memconsole_length;
+
+static ssize_t memconsole_read(struct file *filp, struct kobject *kobp,
+                               struct bin_attribute *bin_attr, char *buf,
+                               loff_t pos, size_t count)
+{
+        return memory_read_from_buffer(buf, count, &pos, memconsole_baseaddr,
+                                       memconsole_length);
+}
+
+static struct bin_attribute memconsole_bin_attr = {
+        .attr = {.name = "log", .mode = 0444},
+        .read = memconsole_read,
+};
+
+
+static void found_v1_header(struct biosmemcon_ebda *hdr)
+{
+        printk(KERN_INFO "BIOS console v1 EBDA structure found at %p\n", hdr);
+        printk(KERN_INFO "BIOS console buffer at 0x%.8x, "
+               "start = %d, end = %d, num = %d\n",
+               hdr->v1.buffer_addr, hdr->v1.start,
+               hdr->v1.end, hdr->v1.num_chars);
+
+        memconsole_length = hdr->v1.num_chars;
+        memconsole_baseaddr = phys_to_virt(hdr->v1.buffer_addr);
+}
+
+static void found_v2_header(struct biosmemcon_ebda *hdr)
+{
+        printk(KERN_INFO "BIOS console v2 EBDA structure found at %p\n", hdr);
+        printk(KERN_INFO "BIOS console buffer at 0x%.8x, "
+               "start = %d, end = %d, num_bytes = %d\n",
+               hdr->v2.buffer_addr, hdr->v2.start,
+               hdr->v2.end, hdr->v2.num_bytes);
+
+        memconsole_length = hdr->v2.end - hdr->v2.start;
+        memconsole_baseaddr = phys_to_virt(hdr->v2.buffer_addr
+                                           + hdr->v2.start);
+}
+
+/*
+ * Search through the EBDA for the BIOS Memory Console, and
+ * set the global variables to point to it.  Return true if found.
+ */
+static bool found_memconsole(void)
+{
+        unsigned int address;
+        size_t length, cur;
+
+        address = get_bios_ebda();
+        if (!address) {
+                printk(KERN_INFO "BIOS EBDA non-existent.\n");
+                return false;
+        }
+
+        /* EBDA length is byte 0 of EBDA (in KB) */
+        length = *(u8 *)phys_to_virt(address);
+        length <<= 10; /* convert to bytes */
+
+        /*
+         * Search through EBDA for BIOS memory console structure
+         * note: signature is not necessarily dword-aligned
+         */
+        for (cur = 0; cur < length; cur++) {
+                struct biosmemcon_ebda *hdr = phys_to_virt(address + cur);
+
+                /* memconsole v1 */
+                if (hdr->signature == BIOS_MEMCONSOLE_V1_MAGIC) {
+                        found_v1_header(hdr);
+                        return true;
+                }
+
+                /* memconsole v2 */
+                if (hdr->signature == BIOS_MEMCONSOLE_V2_MAGIC) {
+                        found_v2_header(hdr);
+                        return true;
+                }
+        }
+
+        printk(KERN_INFO "BIOS console EBDA structure not found!\n");
+        return false;
+}
+
+static struct dmi_system_id memconsole_dmi_table[] __initdata = {
+        {
+                .ident = "Google Board",
+                .matches = {
+                        DMI_MATCH(DMI_BOARD_VENDOR, "Google, Inc."),
+                },
+        },
+        {}
+};
+MODULE_DEVICE_TABLE(dmi, memconsole_dmi_table);
+
+static int __init memconsole_init(void)
+{
+        int ret;
+
+        if (!dmi_check_system(memconsole_dmi_table))
+                return -ENODEV;
+
+        if (!found_memconsole())
+                return -ENODEV;
+
+        memconsole_bin_attr.size = memconsole_length;
+
+        ret = sysfs_create_bin_file(firmware_kobj, &memconsole_bin_attr);
+
+        return ret;
+}
+
+static void __exit memconsole_exit(void)
+{
+        sysfs_remove_bin_file(firmware_kobj, &memconsole_bin_attr);
+}
+
+module_init(memconsole_init);
+module_exit(memconsole_exit);
+
+MODULE_AUTHOR("Google, Inc.");
+MODULE_LICENSE("GPL");
diff --git a/drivers/firmware/iscsi_ibft_find.c b/drivers/firmware/iscsi_ibft_find.c
index 2192456dfd68..f032e446fc11 100644
--- a/drivers/firmware/iscsi_ibft_find.c
+++ b/drivers/firmware/iscsi_ibft_find.c
@@ -42,7 +42,20 @@
 struct acpi_table_ibft *ibft_addr;
 EXPORT_SYMBOL_GPL(ibft_addr);
 
-#define IBFT_SIGN "iBFT"
+static const struct {
+        char *sign;
+} ibft_signs[] = {
+#ifdef CONFIG_ACPI
+        /*
+         * One spec says "IBFT", the other says "iBFT". We have to check
+         * for both.
+         */
+        { ACPI_SIG_IBFT },
+#endif
+        { "iBFT" },
+        { "BIFT" },     /* Broadcom iSCSI Offload */
+};
+
 #define IBFT_SIGN_LEN 4
 #define IBFT_START 0x80000 /* 512kB */
 #define IBFT_END 0x100000 /* 1MB */
@@ -62,6 +75,7 @@ static int __init find_ibft_in_mem(void)
         unsigned long pos;
         unsigned int len = 0;
         void *virt;
+        int i;
 
         for (pos = IBFT_START; pos < IBFT_END; pos += 16) {
                 /* The table can't be inside the VGA BIOS reserved space,
@@ -69,18 +83,23 @@ static int __init find_ibft_in_mem(void)
                 if (pos == VGA_MEM)
                         pos += VGA_SIZE;
                 virt = isa_bus_to_virt(pos);
-                if (memcmp(virt, IBFT_SIGN, IBFT_SIGN_LEN) == 0) {
-                        unsigned long *addr =
-                            (unsigned long *)isa_bus_to_virt(pos + 4);
-                        len = *addr;
-                        /* if the length of the table extends past 1M,
-                         * the table cannot be valid. */
-                        if (pos + len <= (IBFT_END-1)) {
-                                ibft_addr = (struct acpi_table_ibft *)virt;
-                                break;
+
+                for (i = 0; i < ARRAY_SIZE(ibft_signs); i++) {
+                        if (memcmp(virt, ibft_signs[i].sign, IBFT_SIGN_LEN) ==
+                            0) {
+                                unsigned long *addr =
+                                    (unsigned long *)isa_bus_to_virt(pos + 4);
+                                len = *addr;
+                                /* if the length of the table extends past 1M,
+                                 * the table cannot be valid. */
+                                if (pos + len <= (IBFT_END-1)) {
+                                        ibft_addr = (struct acpi_table_ibft *)virt;
+                                        goto done;
+                                }
                         }
                 }
         }
+done:
         return len;
 }
 /*
@@ -89,18 +108,12 @@ static int __init find_ibft_in_mem(void)
  */
 unsigned long __init find_ibft_region(unsigned long *sizep)
 {
-
+        int i;
         ibft_addr = NULL;
 
 #ifdef CONFIG_ACPI
-        /*
-         * One spec says "IBFT", the other says "iBFT". We have to check
-         * for both.
-         */
-        if (!ibft_addr)
-                acpi_table_parse(ACPI_SIG_IBFT, acpi_find_ibft);
-        if (!ibft_addr)
-                acpi_table_parse(IBFT_SIGN, acpi_find_ibft);
+        for (i = 0; i < ARRAY_SIZE(ibft_signs) && !ibft_addr; i++)
+                acpi_table_parse(ibft_signs[i].sign, acpi_find_ibft);
 #endif /* CONFIG_ACPI */
 
         /* iBFT 1.03 section 1.4.3.1 mandates that UEFI machines will