For cache-incoherent DMA, dma_sync_single_for_cpu with DMA_FROM_DEVICE invalidates the cache, so no stale lines in the cache hide what the hardware had written to RAM. On the same systems, dma_sync_single_for_device with DMA_FROM_DEVICE also invalidates the cache, so no dirty lines from the CPU are evicted clobbering what the hardware had written to RAM. In rx_descs_init, the RX buffers need to be invalidated before transferring ownership to the network controller, therefore we should use dma_sync_single_for_device for clarity, even if it doesn't change behavior. Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> --- drivers/net/designware.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/designware.c b/drivers/net/designware.c index 183feba2ea5a..66f28b429dea 100644 --- a/drivers/net/designware.c +++ b/drivers/net/designware.c @@ -156,7 +156,7 @@ static void rx_descs_init(struct eth_device *dev) else desc_p->dmamac_cntl |= DESC_RXCTRL_RXCHAIN; - dma_sync_single_for_cpu(dev->parent, desc_p->dmamac_addr, + dma_sync_single_for_device(dev->parent, desc_p->dmamac_addr, CONFIG_ETH_BUFSIZE, DMA_FROM_DEVICE); desc_p->txrx_status = DESC_RXSTS_OWNBYDMA; } -- 2.39.2
