[PATCH v3 2/2] ftpm: add documentation for ftpm driver
- Date: Mon, 15 Apr 2019 11:56:36 -0400
- From: Sasha Levin <sashal@xxxxxxxxxx>
- Subject: [PATCH v3 2/2] ftpm: add documentation for ftpm driver
This patch adds basic documentation to describe the new fTPM driver.
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
Signed-off-by: Sasha Levin (Microsoft) <sashal@xxxxxxxxxx>
Documentation/security/tpm/index.rst | 1 +
Documentation/security/tpm/tpm_ftpm_tee.rst | 31 +++++++++++++++++++++
2 files changed, 32 insertions(+)
create mode 100644 Documentation/security/tpm/tpm_ftpm_tee.rst
diff --git a/Documentation/security/tpm/index.rst b/Documentation/security/tpm/index.rst
index af77a7bbb070..15783668644f 100644
@@ -4,4 +4,5 @@ Trusted Platform Module documentation
diff --git a/Documentation/security/tpm/tpm_ftpm_tee.rst b/Documentation/security/tpm/tpm_ftpm_tee.rst
new file mode 100644
@@ -0,0 +1,31 @@
+Firmware TPM Driver
+| Thirupathaiah Annapureddy <thiruan@xxxxxxxxxxxxx>
+| Sasha Levin <sashal@xxxxxxxxxx>
+This document describes the firmware Trusted Platform Module (fTPM)
+This driver is a shim for a firmware implemented in ARM's TrustZone
+environment. The driver allows programs to interact with the TPM in the same
+way the would interact with a hardware TPM.
+The driver acts as a thin layer that passes commands to and from a TPM
+implemented in firmware. The driver itself doesn't contain much logic and is
+used more like a dumb pipe between firmware and kernel/userspace.
+The firmware itself is based on the following paper:
+When the driver is loaded it will expose ``/dev/tpmX`` character devices to
+userspace which will enable userspace to communicate with the firmware tpm
+through this device.