This code programs the next descriptor in the TX descriptor ring into the hardware as the last valid TX descriptor. The problem is that if the currenty descriptor is the last one in the array, the code will not wrap around correctly and use TX descriptor 0 again, but instead will use TX descriptor at address right past the TX descriptor ring, which is the first descriptor in the RX ring.
Fix this by adding the necessary wrap-around. Signed-off-by: Marek Vasut <[email protected]> Cc: Joe Hershberger <[email protected]> Cc: Patrice Chotard <[email protected]> Cc: Patrick Delaunay <[email protected]> Cc: Ramon Fried <[email protected]> Cc: Stephen Warren <[email protected]> --- drivers/net/dwc_eth_qos.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/dwc_eth_qos.c b/drivers/net/dwc_eth_qos.c index 4bce6d4290..c4f665bda9 100644 --- a/drivers/net/dwc_eth_qos.c +++ b/drivers/net/dwc_eth_qos.c @@ -1373,7 +1373,8 @@ static int eqos_send(struct udevice *dev, void *packet, int length) tx_desc->des3 = EQOS_DESC3_OWN | EQOS_DESC3_FD | EQOS_DESC3_LD | length; eqos->config->ops->eqos_flush_desc(tx_desc); - writel((ulong)(tx_desc + 1), &eqos->dma_regs->ch0_txdesc_tail_pointer); + writel((ulong)(&(eqos->tx_descs[eqos->tx_desc_idx])), + &eqos->dma_regs->ch0_txdesc_tail_pointer); for (i = 0; i < 1000000; i++) { eqos->config->ops->eqos_inval_desc(tx_desc); -- 2.25.1
