src/drivers/intel/ptt: Add PTT Support

Add function which checks if Intel Platform Trust Technology / Intel
integrated TPM is enabled/active.

Change-Id: If93bb5e1a3a59b5045f4e44359683876fb387a71
Signed-off-by: Christian Walter <christian.walter@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34380
Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 27 insertions, 0 deletions

diff --git a/src/drivers/intel/ptt/ptt.h b/src/drivers/intel/ptt/ptt.h
new file mode 100644
index 0000000000..ed5e90f599
--- /dev/null
+++ b/src/drivers/intel/ptt/ptt.h
@@ -0,0 +1,27 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * 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; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * This driver checks if the PTT Bit is set correctly within the FWSTS4
+ * register. This is needed in order to use the iTPM, because we have to
+ * check prior using the interface that this bit is set correctly - otherwise
+ * it could work unpredictable. The bit should already be set if the Intel ME
+ * is still in the preboot phase.
+ *
+ */
+#include <stdint.h>
+/*
+ * ptt_active
+ *
+ * Checks if the Intel PTT is active. If PTT is active, returns true,
+ * false otherwise.
+ */
+bool ptt_active(void);