drivers/tpm: Add firmware-power-managed DSD property
Introduce firmware-power-managed DSD ACPI property for TPM devices.
This property can be checked by the kernel TPM driver to override how
the TPM power states are managed. This is a tri-state flag, true,
false, or unset. So an enum used to keep the flag is unset by default.
When firmware-power-managed is true, the kernel driver will not send a
shutdown during s2idle/s0i3 suspend.
BUG=b:200578885
BRANCH=None
TEST=TPM shutdown is triggered on s0ix suspend on guybrush with patched
kernel
Change-Id: Ia48ead856fc0c6e637a2e07a5ecc58423f599c5b
Signed-off-by: Rob Barnes <robbarnes@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/59479
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Raul Rangel <rrangel@chromium.org>
diff --git a/src/drivers/i2c/tpm/chip.c b/src/drivers/i2c/tpm/chip.c
index 07791c3..3a2f8aa 100644
--- a/src/drivers/i2c/tpm/chip.c
+++ b/src/drivers/i2c/tpm/chip.c
@@ -11,6 +11,7 @@
static void i2c_tpm_fill_ssdt(const struct device *dev)
{
+ struct acpi_dp *dsd;
struct drivers_i2c_tpm_config *config = dev->chip_info;
const char *scope = acpi_device_scope(dev);
struct acpi_i2c i2c = {
@@ -47,6 +48,21 @@
acpigen_write_resourcetemplate_footer();
+ /* _DSD, Device-Specific Data */
+ dsd = acpi_dp_new_table("_DSD");
+ switch (config->power_managed_mode) {
+ case TPM_FIRMWARE_POWER_MANAGED:
+ acpi_dp_add_integer(dsd, "firmware-power-managed", 1);
+ break;
+ case TPM_KERNEL_POWER_MANAGED:
+ acpi_dp_add_integer(dsd, "firmware-power-managed", 0);
+ break;
+ case TPM_DEFAULT_POWER_MANAGED:
+ default:
+ /* Leave firmware-power-managed unset */
+ }
+ acpi_dp_write(dsd);
+
acpigen_pop_len(); /* Device */
acpigen_pop_len(); /* Scope */