text: /*
   * Copyright (C) 2005 IBM Corporation
   *
   * Authors:
   *	Seiji Munetoh <munetoh@jp.ibm.com>
   *	Stefan Berger <stefanb@us.ibm.com>
   *	Reiner Sailer <sailer@watson.ibm.com>
   *	Kylene Hall <kjhall@us.ibm.com>
   *	Nayna Jain <nayna@linux.vnet.ibm.com>
   *
   * Maintained by: <tpmdd-devel@lists.sourceforge.net>
   *
   * Access to the event log extended by the TCG BIOS of PC platform
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License
   * as published by the Free Software Foundation; either version
   * 2 of the License, or (at your option) any later version.
   *
   */
  
  #include <linux/seq_file.h>
  #include <linux/fs.h>
  #include <linux/security.h>
  #include <linux/module.h>
  #include <linux/slab.h>
  #include <linux/acpi.h>
  #include <linux/tpm_eventlog.h>
  
  #include "tpm.h"
  
  struct acpi_tcpa {
  	struct acpi_table_header hdr;
  	u16 platform_class;
  	union {
  		struct client_hdr {
  			u32 log_max_len __packed;
  			u64 log_start_addr __packed;
  		} client;
  		struct server_hdr {
  			u16 reserved;
  			u64 log_max_len __packed;
  			u64 log_start_addr __packed;
  		} server;
  	};
  };
  
  /* read binary bios log */
  int tpm_read_log_acpi(struct tpm_chip *chip)
  {
  	struct acpi_tcpa *buff;
  	acpi_status status;
  	void __iomem *virt;
  	u64 len, start;
  	struct tpm_bios_log *log;
  
  	if (chip->flags & TPM_CHIP_FLAG_TPM2)
  		return -ENODEV;
  
  	log = &chip->log;
  
  	/* Unfortuntely ACPI does not associate the event log with a specific
  	 * TPM, like PPI. Thus all ACPI TPMs will read the same log.
  	 */
  	if (!chip->acpi_dev_handle)
  		return -ENODEV;
  
  	/* Find TCPA entry in RSDT (ACPI_LOGICAL_ADDRESSING) */
  	status = acpi_get_table(ACPI_SIG_TCPA, 1,
  				(struct acpi_table_header **)&buff);
  
  	if (ACPI_FAILURE(status))
  		return -ENODEV;
  
  	switch(buff->platform_class) {
  	case BIOS_SERVER:
  		len = buff->server.log_max_len;
  		start = buff->server.log_start_addr;
  		break;
  	case BIOS_CLIENT:
  	default:
  		len = buff->client.log_max_len;
  		start = buff->client.log_start_addr;
  		break;
  	}
  	if (!len) {
  		dev_warn(&chip->dev, "%s: TCPA log area empty\n", __func__);
  		return -EIO;
  	}
  
  	/* malloc EventLog space */
  	log->bios_event_log = kmalloc(len, GFP_KERNEL);
  	if (!log->bios_event_log)
  		return -ENOMEM;
  
  	log->bios_event_log_end = log->bios_event_log + len;
  
  	virt = acpi_os_map_iomem(start, len);
  	if (!virt)
  		goto err;
  
  	memcpy_fromio(log->bios_event_log, virt, len);
  
  	acpi_os_unmap_iomem(virt, len);
  	return EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
  
  err:
  	kfree(log->bios_event_log);
  	log->bios_event_log = NULL;
  	return -EIO;
  
  }
  