[PATCH net] net: enetc: fix wrong TPID registers and remove dead branch

[Wei Fang <wei.fang@nxp.com>]

Both PF and VF have rx-vlan-offload enabled, however, the PCVLANR1/2
registers are resources controlled by PF, so VF cannot access these
two registers. Fortunately, the hardware provides SICVLANR1/2 registers
for each SI to reflect the value of PCVLANR1/2 registers. Therefore,
use SICVLANR1/2 instead of PCVLANR1/2.

In addition, since ENETC_RXBD_FLAG_TPID is defined as GENMASK(1, 0),
the possible values are only 0, 1, 2, 3, so the default branch will
never be true, so remove the default branch.

Fixes: 827b6fd04651 ("net: enetc: fix incorrect TPID when receiving 802.1ad tagged packets")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
---
 drivers/net/ethernet/freescale/enetc/enetc.c    | 12 +++++-------
 drivers/net/ethernet/freescale/enetc/enetc_hw.h |  5 +++--
 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
index dcc3fbac3481..e4287725832e 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc.c
@@ -1375,6 +1375,7 @@ static void enetc_get_offloads(struct enetc_bdr *rx_ring,
 	}
 
 	if (le16_to_cpu(rxbd->r.flags) & ENETC_RXBD_FLAG_VLAN) {
+		struct enetc_hw *hw = &priv->si->hw;
 		__be16 tpid = 0;
 
 		switch (le16_to_cpu(rxbd->r.flags) & ENETC_RXBD_FLAG_TPID) {
@@ -1385,15 +1386,12 @@ static void enetc_get_offloads(struct enetc_bdr *rx_ring,
 			tpid = htons(ETH_P_8021AD);
 			break;
 		case 2:
-			tpid = htons(enetc_port_rd(&priv->si->hw,
-						   ENETC_PCVLANR1));
+			tpid = htons(enetc_rd_hot(hw, ENETC_SICVLANR1) &
+				     SICVLANR_ETYPE);
 			break;
 		case 3:
-			tpid = htons(enetc_port_rd(&priv->si->hw,
-						   ENETC_PCVLANR2));
-			break;
-		default:
-			break;
+			tpid = htons(enetc_rd_hot(hw, ENETC_SICVLANR2) &
+				     SICVLANR_ETYPE);
 		}
 
 		__vlan_hwaccel_put_tag(skb, tpid, le16_to_cpu(rxbd->r.vlan_opt));
diff --git a/drivers/net/ethernet/freescale/enetc/enetc_hw.h b/drivers/net/ethernet/freescale/enetc/enetc_hw.h
index 4098f01479bc..0385aa66a391 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_hw.h
+++ b/drivers/net/ethernet/freescale/enetc/enetc_hw.h
@@ -43,6 +43,9 @@
 
 #define ENETC_SIPMAR0	0x80
 #define ENETC_SIPMAR1	0x84
+#define ENETC_SICVLANR1	0x90
+#define ENETC_SICVLANR2	0x94
+#define  SICVLANR_ETYPE	GENMASK(15, 0)
 
 /* VF-PF Message passing */
 #define ENETC_DEFAULT_MSG_SIZE	1024	/* and max size */
@@ -178,8 +181,6 @@ enum enetc_bdr_type {TX, RX};
 #define ENETC_PSIPMAR0(n)	(0x0100 + (n) * 0x8) /* n = SI index */
 #define ENETC_PSIPMAR1(n)	(0x0104 + (n) * 0x8)
 #define ENETC_PVCLCTR		0x0208
-#define ENETC_PCVLANR1		0x0210
-#define ENETC_PCVLANR2		0x0214
 #define ENETC_VLAN_TYPE_C	BIT(0)
 #define ENETC_VLAN_TYPE_S	BIT(1)
 #define ENETC_PVCLCTR_OVTPIDL(bmp)	((bmp) & 0xff) /* VLAN_TYPE */
-- 
2.34.1