ETM:embedded Trace Macrocell

PTM:Program Flow Trace Macrocell

ETM-A7 macrocell提供Cortex-A7 MPcore的instruction和data的trace。

ETM and PTM-LMLPHP

再与Cortex-A7的连接过程中,需要连接ETM interface和PMU 接口。

ETM interface包括:instruction address,branch,exception,data address,data value等。

ETM内部实现DFT logic,提供DFTSE和DFTRSTDISABLE信号。

ETM内部的block diagram:

ETM and PTM-LMLPHP

PTM是基于Program Flow Trace(PFT)架构的,进行real-time instruction flow tracing的模块。

PTM会copy一份正在执行的code,然后只在一些program execution point进行trace,这样的点叫做waypoint。

Trace tools利用waypoint来follow program的execution。

一般的waypoint包括:

1)indirect branches,with target address and condition code;

2)direct branches with only the condition code;

3)exceptions

4)changes in processor security state

5)changes in processor instruction set state

可以自己config的point:

1)cycle count between traced waypoint

2)global system timestamps

3)target addresses for taken direct branches

PTM集成中的架构图:

ETM and PTM-LMLPHP

PTM模块内部的block diagram:

Processor input FIFO:buffers the output from processor trace interface until the execution of the

waypoint。

ETM and PTM-LMLPHP

Processor与CTI和PTM的连接:

ETM and PTM-LMLPHP

ETM and PTM-LMLPHP

04-26 02:37