Hi, Newer members of the KS3 family (after AM654) have support for burst_size configuration for each DMA channel. The HW default value is 64 bytes but on higher throughput channels it can be increased to 256 bytes (UCHANs) or 128 byes (HCHANs). Aligning the buffers and length of the transfer to the burst size also increases the throughput. Numbers gathered on j721e (UCHAN pair): echo 8000000 > /sys/module/dmatest/parameters/test_buf_size echo 2000 > /sys/module/dmatest/parameters/timeout echo 50 > /sys/module/dmatest/parameters/iterations echo 1 > /sys/module/dmatest/parameters/max_channels Prior to this patch: ~1.3 GB/s After this patch: ~1.8 GB/s with 1 byte alignment: ~1.7 GB/s The patches are on top of the AM64 support series: https://lore.kernel.org/lkml/20201208090440.31792-1-peter.ujfalusi@xxxxxx/ Regards, Peter --- Peter Ujfalusi (2): dmaengine: Extend the dmaengine_alignment for 128 and 256 bytes dmaengine: ti: k3-udma: Add support for burst_size configuration for mem2mem drivers/dma/ti/k3-udma.c | 115 ++++++++++++++++++++++++++++++++++++-- include/linux/dmaengine.h | 2 + 2 files changed, 112 insertions(+), 5 deletions(-) -- Peter Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
