diff options
Diffstat (limited to 'drivers/char/tpm/tpm_eventlog_acpi.c')
-rw-r--r-- | drivers/char/tpm/tpm_eventlog_acpi.c | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm_eventlog_acpi.c b/drivers/char/tpm/tpm_eventlog_acpi.c new file mode 100644 index 000000000000..66f19e93c216 --- /dev/null +++ b/drivers/char/tpm/tpm_eventlog_acpi.c @@ -0,0 +1,112 @@ +/* + * 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; + +} |