On 11/11/2025 04:54, Alex Bennée wrote:
The datasheet doesn't explicitly say that TXFR_LEN has to be word aligned but the fact there is a DMA_D_WIDTH flag to select between 32 bit and 128 bit strongly implies that is how it works. The downstream
At the bottom of page 38, the datasheet [1] states "the DMA can deal with byte aligned transfers and will minimise bus traffic by buffering and packing misaligned accesses." IIUC, the *_WIDTH info fields are implied as maxima. [1] https://datasheets.raspberrypi.com/bcm2835/bcm2835-peripherals.pdf Regards, Yodel
rpi kernel also goes to efforts to not write sub-4 byte lengths so lets:
