Idle and Reset of Peripherals - 2020.2 English

Zynq UltraScale+ MPSoC Software Developer Guide (UG1137)

Document ID
Release Date
2020.2 English

It is necessary to stop/complete any ongoing transaction by any IP or processor of the subsystem before resetting them. Otherwise, it may lead to hanging of the interconnect and eventually hanging of the entire system. Also, to ensure proper operation by the IP after reboot, it is best to reset them and bring them to post bootROM state.

PMU firmware implements peripheral idling and resetting for the PS IPs that can be idled / reset during the subsystem reset. The IPs that will be attempted to idled/reset is based on isolation configuration of the Vivado.

Build PMU firmware with the following idling flags to enable subsystem node idling and resetting:


Node Reset and Idle

During a subsystem restart, the PMU firmware makes sure that the associated PS peripheral nodes are idled and brought to reset state. Following is the list of currently supported PS peripherals that will undergo idle/reset, if they are part of the subsystem that is undergoing reset:

  • TTC
  • Ethernet/EMAC
  • I2C
  • SD
  • eMMC
  • QSPI
  • USB
  • DP
  • SATA

See GPIO reset to PL to understand the implication of GPIO reset.

Note: PS peripherals are idled prior to invoking resets for user invoked reboot of PS-only and system-reset command.