On Thu, Jun 25, 2020 at 05:50:00PM -0400, Stefan Berger wrote:
> From: Stefan Berger <stefanb@xxxxxxxxxxxxx>
>
> In case a TPM2 is attached, search for a TPM2 ACPI table when trying
> to get the event log from ACPI. If one is found, use it to get the
> start and length of the log area. This allows non-UEFI systems, such
> as SeaBIOS, to pass an event log when using a TPM2.
>
> Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
> ---
> drivers/char/tpm/eventlog/acpi.c | 62 +++++++++++++++++++++-----------
> 1 file changed, 41 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/char/tpm/eventlog/acpi.c b/drivers/char/tpm/eventlog/acpi.c
> index 63ada5e53f13..e2258cfa6cb1 100644
> --- a/drivers/char/tpm/eventlog/acpi.c
> +++ b/drivers/char/tpm/eventlog/acpi.c
> @@ -49,9 +49,9 @@ int tpm_read_log_acpi(struct tpm_chip *chip)
> void __iomem *virt;
> u64 len, start;
> struct tpm_bios_log *log;
> -
> - if (chip->flags & TPM_CHIP_FLAG_TPM2)
> - return -ENODEV;
> + struct acpi_table_tpm2 *tbl;
> + struct acpi_tpm2_phy *t2phy;
> + int format;
>
> log = &chip->log;
>
> @@ -61,23 +61,43 @@ int tpm_read_log_acpi(struct tpm_chip *chip)
> 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 (chip->flags & TPM_CHIP_FLAG_TPM2) {
> + status = acpi_get_table("TPM2", 1,
> + (struct acpi_table_header **)&tbl);
> + if (ACPI_FAILURE(status))
> + return -ENODEV;
> +
> + if (tbl->header.length <
> + sizeof(*tbl) + sizeof(struct acpi_tpm2_phy))
> + return -ENODEV;
> +
> + t2phy = (void *)tbl + sizeof(*tbl);
> + len = t2phy->log_area_minimum_length;
> +
> + start = t2phy->log_area_start_address;
> + if (!start || !len)
> + return -ENODEV;
> +
> + format = EFI_TCG2_EVENT_LOG_FORMAT_TCG_2;
> + } else {
> + /* 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;
> + }
Empty line as in the first branch after the conditional statement.
> + format = EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
> }
> if (!len) {
> dev_warn(&chip->dev, "%s: TCPA log area empty\n", __func__);
> @@ -98,7 +118,7 @@ int tpm_read_log_acpi(struct tpm_chip *chip)
> memcpy_fromio(log->bios_event_log, virt, len);
>
> acpi_os_unmap_iomem(virt, len);
> - return EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
> + return format;
>
> err:
> kfree(log->bios_event_log);
> --
> 2.26.2
>
/Jarkko
