Off the top of my head, secure world interrupts(SPI's, PPI's, SGI's), MMU mappings for anything that does not depend on image layout(platform specific devices, UEFI MM or other special regions), security policies like TZC region protections.

-Raghu

On 5/14/20 8:45 AM, Madhukar Pappireddy via TF-A wrote:

Hi,

We are in the process of leveraging the fconf framework to make the static configurations of various components of TF-A to more dynamic configurations. The primary motivation behind this effort is to evaluate the possibility of having common TF-A BL images that can be used across multiple platforms. As a start, this involves moving compile-time C based data structures into device tree which are extracted during runtime. We have chosen the FVP platform as a proof of concept for this effort and have identified the following components to be made more dynamic:

runtime UART std-out: https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/3775, https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/3923/

Topology description: https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/3492, https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/3522

GICv3 configuration: https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/4066

Timer configuration: https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/3696

SDEI platform setup: https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/3990

CoT descriptor: https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/4080, https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/4081

Platform IO Policies: https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/2558

Please advise if there are any other components of TF-A that can be configured dynamically in runtime.

Thanks,

Madhu