How to check the enable status in ETM v3.3

Hi all,

I am trying to use the ETM on iMX53 qsb, which contains a Cortex-A8 processor. In the board, the trace result of the ETM is outputted to both ETB and TPIU via an ATB replicator, looks like the following figure,

I am going to enable the ETM and read the trace result from the ETM. Thus, I followed the example in http://infocenter.arm.com/help/topic/com.arm.doc.ihi0014q/IHI0014Q_etm_architecture_spec.pdf section 3.5.7 to configure the ETM, and enabled the ETB by setting the ETB control register. In this board, there is no funnel between the ETB and ETM, and also no programmable registers for the replicator, so I guess my configuration should work. 

However, it turns out that I cannot get any output from the ETB. I am not sure what has happened, and try to find out whether the ETM is working. Unlike the Trace Status Register in the ETM v4 specification, it seems that there is no register showing whether the trace unit is idle or not in the ETM v3.3 specification. The value of ETMSR register is 0x8 after i enabled the ETM, but i am not sure whether it indicates the ETM is working or not.

Is there anyone has experience on ETM v3.3 and know what is happening?

Appreciate for any help and discussion.

Best Regards,

Zhenyu