Linux kernel latest source http://mirrors.hust.edu.cn/git/linux-next.git/atom?h=master 2026-07-09T19:12:58+00:00 2026-07-09T19:12:58+00:00 Sumit Garg sumit.garg@oss.qualcomm.com 2026-07-02T11:58:17+00:00 urn:sha1:08314e7c2c38b9ae6a5e01c58ed10a950859404d 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 using S-EL2 with 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. Reviewed-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com> Tested-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com> # Lemans Reviewed-by: Harshal Dev <harshal.dev@oss.qualcomm.com> Tested-by: Vignesh Viswanathan <vignesh.viswanathan@oss.qualcomm.com> # IPQ9650 Signed-off-by: Sumit Garg <sumit.garg@oss.qualcomm.com> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> Link: https://lore.kernel.org/r/20260702115835.167602-2-sumit.garg@kernel.org Signed-off-by: Bjorn Andersson <andersson@kernel.org>