Hard Processor System Technical Reference Manual: Agilex™ 5 SoCs

ID 814346
Date 4/01/2024
Public
Document Table of Contents

15.5.1.3. DAP SWJ-DP Debug Clock Enable Request

The HPS uses the DAP’s CDBGPWRUPREQ/ACK signal to allow the debugger easy access to turn on clocks to the CoreSight subsystem. The debugger enables the CoreSight network clocks from the JTAG TCLK domain using the DAP’s built-in debug power up request without having to know the memory mapped location of debug clock enables within the HPS clock manager.

Use DAP SWJ-DP’s CDBGPWRUPREQ/ACK signals:

  • Driven by a register in the TCLK domain and must be synchronized before use.
  • Connect to the HPS clock manager and enable CoreSight subsystem clocks when the CDBGPWRUPREQ signal is asserted.
  • The CDBGPWRUPACK input can be used to acknowledge CDBGPWRUPREQ as Arm* recommends, or a pulse can be sent to the clock manager to request the clocks be enabled. If a pulse is used, tie the CDBGPWRUPACK input signal directly to the CDBGPWRUPREQ output signal.