[PATCH v1 1/2] net: designware: eqos: fix receive issue with external switch

[Oleksij Rempel]

Do not drop packets with error status (CRC error, receive error, watchdog
timeout, or overflow) otherwise we wont be able to receive packets from
a switch with enabled tagging.

In case we have switch with tagging enabled, ingress packets will be
modified by the switch. Most probably this will affect CRC calculation,
so all incoming packets are dropped.

Setting FEP and FUP is recommended programming model described in
STM32MP157 reference manual. See "64.9.2 MTL initialization":

Signed-off-by: Oleksij Rempel <o.rempel at pengutronix.de>
---
 drivers/net/designware_eqos.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/designware_eqos.c b/drivers/net/designware_eqos.c
index 8d2a21c220..1f97d84880 100644
--- a/drivers/net/designware_eqos.c
+++ b/drivers/net/designware_eqos.c
@@ -112,6 +112,8 @@ struct eqos_mtl_regs {
 #define EQOS_MTL_RXQ0_OPERATION_MODE_RFA_MASK		0x3f
 #define EQOS_MTL_RXQ0_OPERATION_MODE_EHFC		BIT(7)
 #define EQOS_MTL_RXQ0_OPERATION_MODE_RSF		BIT(5)
+#define EQOS_MTL_RXQ0_OPERATION_MODE_FEP		BIT(4)
+#define EQOS_MTL_RXQ0_OPERATION_MODE_FUP		BIT(3)
 
 #define EQOS_MTL_RXQ0_DEBUG_PRXQ_SHIFT			16
 #define EQOS_MTL_RXQ0_DEBUG_PRXQ_MASK			0x7fff
@@ -433,7 +435,9 @@ static int eqos_start(struct eth_device *edev)
 
 	/* Enable Store and Forward mode for RX, since no jumbo frame */
 	setbits_le32(&eqos->mtl_regs->rxq0_operation_mode,
-		     EQOS_MTL_RXQ0_OPERATION_MODE_RSF);
+		     EQOS_MTL_RXQ0_OPERATION_MODE_RSF |
+		     EQOS_MTL_RXQ0_OPERATION_MODE_FEP |
+		     EQOS_MTL_RXQ0_OPERATION_MODE_FUP);
 
 	/* Transmit/Receive queue fifo size; use all RAM for 1 queue */
 	val = readl(&eqos->mac_regs->hw_feature1);
-- 
2.30.2