SPRZ452I july 2018 – may 2023 AM6526 , AM6528 , AM6546 , AM6548
UART: Spurious UART Interrupts When Using DMA
Spurious UART interrupts may occur when DMA mode (UART_FCR[3] DMA_MODE) is enabled and DMA is used to read data from RX FIFO. The Interrupt Controller flags that a UART interrupt has occurred; however, the associated UART_IIR_UART[0] IT_PENDING bit remains set to 1, indicating that no interrupt is pending.
Acknowledge the spurious interrupts for every occurrence. The issue can be avoided by disabling Receive Data Interrupt (RDI) using the UART_IER_UART[0] RHR_IT bit; however, be aware that this also disables RX timeout interrupts, which may not be practical for all use cases.