On Fri, Mar 13, 2026 at 01:29:48PM +0530, Mukesh Ojha wrote:

On Thu, Mar 12, 2026 at 11:57:43AM +0530, Sumit Garg wrote:

quoted

From: Sumit Garg <redacted>

Qcom platforms has the legacy of using non-standard SCM calls
splintered over the various kernel drivers. These SCM calls aren't
compliant with the standard SMC calling conventions which is a
prerequisite to enable migration to the FF-A specifications from Arm.

OP-TEE as an alternative trusted OS to Qualcomm TEE (QTEE) can't
support these non-standard SCM calls. And even for newer architectures
with S-EL2 and Hafnium support, QTEE won't be able to support SCM
calls either with FF-A requirements coming in. And with both OP-TEE
and QTEE drivers well integrated in the TEE subsystem, it makes further
sense to reuse the TEE bus client drivers infrastructure.

The added benefit of TEE bus infrastructure is that there is support
for discoverable/enumerable services. With that client drivers don't
have to manually invoke a special SCM call to know the service status.

So enable the generic Peripheral Authentication Service (PAS) provided
by the firmware. It acts as the common layer with different TZ
backends plugged in whether it's an SCM implementation or a proper
TEE bus based PAS service implementation.

Signed-off-by: Sumit Garg <redacted>
---
 drivers/firmware/qcom/Kconfig          |   8 +
 drivers/firmware/qcom/Makefile         |   1 +
 drivers/firmware/qcom/qcom_pas.c       | 298 +++++++++++++++++++++++++
 drivers/firmware/qcom/qcom_pas.h       |  53 +++++
 include/linux/firmware/qcom/qcom_pas.h |  41 ++++
 5 files changed, 401 insertions(+)
 create mode 100644 drivers/firmware/qcom/qcom_pas.c
 create mode 100644 drivers/firmware/qcom/qcom_pas.h
 create mode 100644 include/linux/firmware/qcom/qcom_pas.h

<snip>

quoted

diff --git a/drivers/firmware/qcom/qcom_pas.c b/drivers/firmware/qcom/qcom_pas.c
new file mode 100644
index 000000000000..beb1bae55546
--- /dev/null
+++ b/drivers/firmware/qcom/qcom_pas.c

@@ -0,0 +1,298 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
+ */

I know, this is new file but most of the documentation and some of the
function are rename to reflect pas service.

Should this carry original file copyright ? Not sure..

This file only contains the wrapper generic PAS APIs which aren't
re-used from any other file. Carrying copyrights solely based on moving
API documentation in not very clear to me. Any other thoughts?

-Sumit