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Most Qualcomm platforms feature Gunyah hypervisor, which typically handles IOMMU configuration. This includes mapping memory regions and device memory resources for remote processors by intercepting qcom_scm_pas_auth_and_reset() calls. These mappings are later removed during teardown. Additionally, SHM bridge setup is required to enable memory protection for both remoteproc metadata and its memory regions. When the aforementioned hypervisor is absent, the operating system must perform these configurations instead. When Linux runs as the hypervisor (@ EL2) on a SoC, it will have its own device tree overlay file that specifies the firmware stream ID now managed by Linux for a particular remote processor. If the iommus property is specified in the remoteproc device tree node, it indicates that IOMMU configuration must be handled by Linux. In this case, the has_iommu flag is set for the remote processor, which ensures that the resource table, carveouts, and SHM bridge are properly configured before memory is passed to TrustZone for authentication. Otherwise, the has_iommu flag remains unset, which indicates default behavior. Enables Secure PAS support for remote processors when IOMMU configuration is managed by Linux. Signed-off-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com> Link: https://lore.kernel.org/r/20260105-kvmrprocv10-v10-13-022e96815380@oss.qualcomm.com Signed-off-by: Bjorn Andersson <andersson@kernel.org>