SPRUHZ7K August 2015 – April 2024 AM5706 , AM5708 , AM5716 , AM5718 , AM5718-HIREL
DSP C66x CPU traffic initiated on the DSP MDMA port can be optionally routed through the DSP_MMU0 on the 32-bit MDMA address path. This is controlled in two levels :
For the DSP_MMU0 to operate, SW should enable it both at the DSP_SYSTEM global level and DSP_MMU0 local register level.
When enabling the DSP_MMU0, software must take care that no transactions are in flight through that MMU. This is typically handled by issueing a DSP "MFENCE" instruction operation. Note that the local enable bit inside the DSP_MMU0 must be configured as normal (refer to the Chapter 20, Memory Management Units.)
For more information on the MFENCE operation, refer to the section, C66x CPU Instruction Set of the TMS320C66x DSP CPU and Instruction Set ).
In addition, the DSP_MMU0 traffic can be aborted in case of a lockup via the DSP_SYS_MMU_CONFIG [8] MMU0_ABORT bit. In other words, this bit can be used to clear a hang condition that may occur if the DSP_MMU0 encounters a page fault that cannot be serviced.
For more information on device DSP_MMU0 functionality and register settings, refer to the Section 20.3, MMU Functional Description and Section 20.5, MMU Register Manual, in the chapter, Memory Management Units, respectively.