Arria V Hard Processor System Technical Reference Manual

ID 683011
Date 12/02/2022
Public
Document Table of Contents

19.4.4.2. Hardware Reset

Each of the USB OTG controllers has one reset input from the reset manager. The reset signal is asserted during a cold or warm reset event. The reset manager holds the controllers in reset until software releases the resets. Software releases resets by clearing the appropriate USB bits in the Peripheral Module Reset Register (permodrst) in the HPS reset manager.

The reset input resets the following blocks:

  • The master and slave interface logic
  • The integrated DMA controller
  • The internal FIFO buffers
  • The CSR

The reset input is synchronized to the usb_mp_clk domain. The reset input is also synchronized to the ULPI clock within the USB OTG controller and is used to reset the ULPI PHY domain logic.