CRITICALITY

Medium

DESCRIPTION

All UART modules in the SoC do not acknowledge an idle request after enabling the module's DMA feature, even if the DMA is subsequently disabled. Thus, the UART module cannot be clock idled after enabling DMA with

• UART_SCR.DMA_MODE_CTL = 1 and UART_SCR.DMA_MODE_2 != 0
  

  OR

  
  
• UART_SCR.DMA_MODE_CTL = 0 and UART_FCR.DMA_MODE = 1

A consequence of this is that UARTx_CLKCTRL will remain in transition when trying to disable the module (UARTx_CLKCTRL = 0x10000) and the associated CLKACTIVITY bit will remain active.

WORKAROUND

Initiating a soft reset (UART_SYSC.SOFTRESET = 1) will allow the module to acknowledge the idle request.

REVISIONS IMPACTED

AM574x SR 1.0
AM576x SR 1.0

AM574x: 1.0

DRA75xP, DRA74xP, DRA77xP, DRA76xP: 1.0

TDA2Px: 1.0

AM576x: 1.0