[PATCH v2 net-next 10/21] net: usb: aqc111: Add checksum offload support

[Igor Russkikh <Igor.Russkikh@xxxxxxxxxxxx>]

From: Dmitry Bezrukov <dmitry.bezrukov@xxxxxxxxxxxx>

Signed-off-by: Dmitry Bezrukov <dmitry.bezrukov@xxxxxxxxxxxx>
Signed-off-by: Igor Russkikh <igor.russkikh@xxxxxxxxxxxx>
---
 drivers/net/usb/aqc111.c | 38 ++++++++++++++++++++++++++++++++++++++
 drivers/net/usb/aqc111.h | 16 ++++++++++++++--
 2 files changed, 52 insertions(+), 2 deletions(-)

diff --git a/drivers/net/usb/aqc111.c b/drivers/net/usb/aqc111.c
index ae101b44a109..90061157b7ac 100644
--- a/drivers/net/usb/aqc111.c
+++ b/drivers/net/usb/aqc111.c
@@ -536,6 +536,26 @@ static void aqc111_configure_rx(struct usbnet *dev,
 	netdev_info(dev->net, "Link Speed %d, USB %d", link_speed, usb_host);
 }
 
+static void aqc111_configure_csum_offload(struct usbnet *dev)
+{
+	u8 reg8 = 0;
+
+	if (dev->net->features & NETIF_F_RXCSUM) {
+		reg8 |= SFR_RXCOE_IP | SFR_RXCOE_TCP | SFR_RXCOE_UDP |
+			SFR_RXCOE_TCPV6 | SFR_RXCOE_UDPV6;
+	}
+	aqc111_write_cmd(dev, AQ_ACCESS_MAC, SFR_RXCOE_CTL, 1, 1, &reg8);
+
+	reg8 = 0;
+	if (dev->net->features & NETIF_F_IP_CSUM)
+		reg8 |= SFR_TXCOE_IP | SFR_TXCOE_TCP | SFR_TXCOE_UDP;
+
+	if (dev->net->features & NETIF_F_IPV6_CSUM)
+		reg8 |= SFR_TXCOE_TCPV6 | SFR_TXCOE_UDPV6;
+
+	aqc111_write_cmd(dev, AQ_ACCESS_MAC, SFR_TXCOE_CTL, 1, 1, &reg8);
+}
+
 static int aqc111_link_reset(struct usbnet *dev)
 {
 	struct aqc111_data *aqc111_data = dev->driver_priv;
@@ -579,6 +599,8 @@ static int aqc111_link_reset(struct usbnet *dev)
 		aqc111_write16_cmd(dev, AQ_ACCESS_MAC, SFR_MEDIUM_STATUS_MODE,
 				   2, &reg16);
 
+		aqc111_configure_csum_offload(dev);
+
 		aqc111_read16_cmd(dev, AQ_ACCESS_MAC, SFR_MEDIUM_STATUS_MODE,
 				  2, &reg16);
 
@@ -704,6 +726,21 @@ static int aqc111_stop(struct usbnet *dev)
 	return 0;
 }
 
+static void aqc111_rx_checksum(struct sk_buff *skb, u64 *pkt_desc)
+{
+	u32 pkt_type = 0;
+
+	skb->ip_summed = CHECKSUM_NONE;
+	/* checksum error bit is set */
+	if (*pkt_desc & AQ_RX_PD_L4_ERR || *pkt_desc & AQ_RX_PD_L3_ERR)
+		return;
+
+	pkt_type = *pkt_desc & AQ_RX_PD_L4_TYPE_MASK;
+	/* It must be a TCP or UDP packet with a valid checksum */
+	if (pkt_type == AQ_RX_PD_L4_TCP || pkt_type == AQ_RX_PD_L4_UDP)
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+}
+
 static int aqc111_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
 {
 	struct sk_buff *new_skb = NULL;
@@ -782,6 +819,7 @@ static int aqc111_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
 		skb_set_tail_pointer(new_skb, new_skb->len);
 
 		new_skb->truesize = new_skb->len + sizeof(struct sk_buff);
+		aqc111_rx_checksum(new_skb, pkt_desc);
 
 		usbnet_skb_return(dev, new_skb);
 		if (pkt_count == 0)
diff --git a/drivers/net/usb/aqc111.h b/drivers/net/usb/aqc111.h
index aa0b37ebabae..20637fd58be3 100644
--- a/drivers/net/usb/aqc111.h
+++ b/drivers/net/usb/aqc111.h
@@ -63,8 +63,11 @@
 #define AQ_USB_SET_TIMEOUT		4000
 
 /* Feature. ********************************************/
-#define AQ_SUPPORT_FEATURE	(NETIF_F_SG)
-#define AQ_SUPPORT_HW_FEATURE	(NETIF_F_SG)
+#define AQ_SUPPORT_FEATURE	(NETIF_F_SG | NETIF_F_IP_CSUM |\
+				 NETIF_F_IPV6_CSUM | NETIF_F_RXCSUM)
+
+#define AQ_SUPPORT_HW_FEATURE	(NETIF_F_SG | NETIF_F_IP_CSUM |\
+				 NETIF_F_IPV6_CSUM | NETIF_F_RXCSUM)
 
 /* SFR Reg. ********************************************/
 
@@ -205,6 +208,15 @@ struct aqc111_data {
 #define AQ_RX_HW_PAD			0x02
 
 /* RX Packet Descriptor */
+#define AQ_RX_PD_L4_ERR		BIT(0)
+#define AQ_RX_PD_L3_ERR		BIT(1)
+#define AQ_RX_PD_L4_TYPE_MASK	0x1C
+#define AQ_RX_PD_L4_UDP		0x04
+#define AQ_RX_PD_L4_TCP		0x10
+#define AQ_RX_PD_L3_TYPE_MASK	0x60
+#define AQ_RX_PD_L3_IP		0x20
+#define AQ_RX_PD_L3_IP6		0x40
+
 #define AQ_RX_PD_RX_OK		BIT(11)
 #define AQ_RX_PD_DROP		BIT(31)
 #define AQ_RX_PD_LEN_MASK	0x7FFF0000
-- 
2.7.4