I'm facing an issue wich makes me very confused : I would like to enable the secure partition in ARM Trusted Firmware and also enable the "MM Mode" in EDK2 in order to communicate between the "Normal World" in EL2 and the "Secure World" EL0-S.
I enbaled the SPM through ARM_TF_ENABLE_SPM flag. I also set BL32 et BL33 files path during ARM TF compilation.
In my trusted firmware source code, MM communication buffer (SP_IMAGE_NS_BUF_MAP) is mapped at 0xFF600000 with MT_RW_DATA | MT_NS | MT_USER
And is also reported in plat_arm_secure_partition_mmap
In Uefi, I added the StandalonePkg, wich compiles in "mm_standalone.bin" for BL32 file.
ArmMMCommunation DXE driver has been added in my EDK2.
Unfortunately, every attempt of MM comunication (through 0xFF600000) leads to an Serror Exception, wich could means that access is denied.
Thanks in advance for your help,
Fabrice DECROP LONGET
It may be helpful if you can provide more details about the SError information.
By the default, the TF-A MM mode and UEFI/EDK2 can work. Arm provides one reference software stack based on N1SDP board, which can work well.
We are not sure what is your current development platform, anyway, you can compare and do some analysis against our reference software stack.