drivers/char/tpm/tpm_of.c

   1 /*
   2  * Copyright 2012 IBM Corporation
   3  *
   4  * Author: Ashley Lai <ashleydlai@gmail.com>
   5  *         Nayna Jain <nayna@linux.vnet.ibm.com>
   6  *
   7  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
   8  *
   9  * Read the event log created by the firmware on PPC64
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License
  13  * as published by the Free Software Foundation; either version
  14  * 2 of the License, or (at your option) any later version.
  15  *
  16  */
  17
  18 #include <linux/slab.h>
  19 #include <linux/of.h>
  20
  21 #include "tpm.h"
  22 #include "tpm_eventlog.h"
  23
  24 int tpm_read_log_of(struct tpm_chip *chip)
  25 {
  26         struct device_node *np;
  27         const u32 *sizep;
  28         const u64 *basep;
  29         struct tpm_bios_log *log;
  30
  31         log = &chip->log;
  32         if (chip->dev.parent && chip->dev.parent->of_node)
  33                 np = chip->dev.parent->of_node;
  34         else
  35                 return -ENODEV;
  36
  37         sizep = of_get_property(np, "linux,sml-size", NULL);
  38         basep = of_get_property(np, "linux,sml-base", NULL);
  39         if (sizep == NULL && basep == NULL)
  40                 return -ENODEV;
  41         if (sizep == NULL || basep == NULL)
  42                 return -EIO;
  43
  44         if (*sizep == 0) {
  45                 dev_warn(&chip->dev, "%s: Event log area empty\n", __func__);
  46                 return -EIO;
  47         }
  48
  49         log->bios_event_log = kmalloc(*sizep, GFP_KERNEL);
  50         if (!log->bios_event_log)
  51                 return -ENOMEM;
  52
  53         log->bios_event_log_end = log->bios_event_log + *sizep;
  54
  55         memcpy(log->bios_event_log, __va(*basep), *sizep);
  56
  57         return 0;
  58 }