WebOne way would be to poll and check the serial Rx buffer for data or check the value of hdmarx->Instance->CNDTR if changed from the default value of buffer size. The second option would be to use an IDLE interrupt to know if data is received, this can be done by adding a few lines in HAL_UART_IRQHandler WebThe three main components of this are: (1) dma-buf, representing a sg_table and exposed to userspace as a file descriptor to allow passing between devices, (2) fence, which provides a mechanism to signal when one device as finished access, and (3) reservation, which manages the shared or exclusive fence (s) associated with the buffer.
iMX8, enabling SDMA on UART1 causes problems - NXP Community
WebI've done the following on NXP IMX RT and Kinetis series, as well as STM chips: Most UART peripherals have a UART timeout or idle interrupt so I set up DMA to fill buffer and give me an interrupt when byte count is reached. The UART interrupt is set for idle or timeout. If I get a DMA interrupt, I need to get more data. WebThe callback doesn't care, but the DMA controller cares about this flag. I see a possible race condition here. If i set the DONE flag for a specific buffer descriptor before handling the data belonging to this buffer descriptor (aka running the callback function) the DMA script running at the same time could corrupt that data while being processed. flowy casual sleeveless dress
DMA buffer sharing in 3.3 [LWN.net]
Webmany small packets via UART - causing many dma transfers but in each only filling a fraction of a single buffer. Such a case may lead to the situation that DMA RX transfer is triggered … WebAug 7, 2024 · > then disabling the UART, disabling the DMA channel, reinitialize the DMA control structure, enable the DMA channel and then enable the UART is the correct method to cancel a previously known incomplete buffer. okay, that the answer.. To tell the truth I expected more elegant way.. Any case, thank you for the answer. I close the issue WebSo, rename this option to DEBUG_IMX27_UART and adjust dependencies in Kconfig and rename the definitions to IMX27 as further clean-up. This issue was discovered with ./scripts/checkkconfigsymbols.py, which reported that DEBUG_IMX21_IMX27_UART depends on the non-existing config SOC_IMX21. green county extension