[Tf-a-tests] How to write a Trusted Application in Cactus OS?

Hi all,

I want to write a TA which will be called from the Normal World and be handled by specific Cactus OS.

Specifically, to call the TA, I think I should pass (1) the ID of the TA (but I am not sure how to get the ID) (2) several parameters, which may be loaded into registers. Here may be a calling process.

ldr x0,=0xdeadbeef // loading ID ldr x1,=0x11111 // input parameters ldr x2,=0x22222 // input parameters smc #0

Then I think I should write a corresponding handler (of the TA) in Cactus OS. When we call "smc #0", EL3 will trap it, and route it to a specific TA.

However, I don't know how to do it. Can you provide some useful examples?

Sincerely, Wang Chenxu