Here are the data structures with brief descriptions:

ARM_TF_CPU_DRIVER_EP_DESCRIPTOR
EFI_MM_COMMUNICATE_FV_DISPATCH
EFI_MM_COMMUNICATE_FV_DISPATCH_DATA
EFI_MMRAM_HOB_DESCRIPTOR_BLOCK
EFI_PARAM_HEADER
EFI_SECURE_PARTITION_BOOT_INFO
EFI_SECURE_PARTITION_CPU_INFO
MM_CORE_DATA_HOB_DATA
MM_CORE_PRIVATE_DATA
MP_INFORMATION_HOB_DATA