[PATCH net-next v5 12/14] net: ethernet: oa_tc6: add helper function to enable zero align rx frame

[Parthiban Veerasooran]

Zero align receive frame feature can be enabled to align all receive
ethernet frames data to start at the beginning of any receive data chunk
payload with a start word offset (SWO) of zero. Receive frames may begin
anywhere within the receive data chunk payload when this feature is not
enabled.

Signed-off-by: Parthiban Veerasooran <Parthiban.Veerasooran@xxxxxxxxxxxxx>
---
 drivers/net/ethernet/oa_tc6.c | 23 +++++++++++++++++++++++
 include/linux/oa_tc6.h        |  1 +
 2 files changed, 24 insertions(+)

diff --git a/drivers/net/ethernet/oa_tc6.c b/drivers/net/ethernet/oa_tc6.c
index 7f684b542bb1..9a60f25e8de6 100644
--- a/drivers/net/ethernet/oa_tc6.c
+++ b/drivers/net/ethernet/oa_tc6.c
@@ -23,6 +23,7 @@
 /* Configuration Register #0 */
 #define OA_TC6_REG_CONFIG0			0x0004
 #define CONFIG0_SYNC				BIT(15)
+#define CONFIG0_ZARFE_ENABLE			BIT(12)
 
 /* Status Register #0 */
 #define OA_TC6_REG_STATUS0			0x0008
@@ -1152,6 +1153,28 @@ static irqreturn_t oa_tc6_macphy_isr(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
+/**
+ * oa_tc6_zero_align_receive_frame_enable - function to enable zero align receive
+ * frame feature.
+ * @tc6: oa_tc6 struct.
+ *
+ * Return: 0 on success otherwise failed.
+ */
+int oa_tc6_zero_align_receive_frame_enable(struct oa_tc6 *tc6)
+{
+	u32 regval;
+	int ret;
+
+	ret = oa_tc6_read_register(tc6, OA_TC6_REG_CONFIG0, &regval);
+	if (ret)
+		return ret;
+
+	/* Set Zero-Align Receive Frame Enable */
+	regval |= CONFIG0_ZARFE_ENABLE;
+
+	return oa_tc6_write_register(tc6, OA_TC6_REG_CONFIG0, regval);
+}
+
 /**
  * oa_tc6_start_xmit - function for sending the tx skb which consists ethernet
  * frame.
diff --git a/include/linux/oa_tc6.h b/include/linux/oa_tc6.h
index 5c7811ac9cbe..15f58e3c56c7 100644
--- a/include/linux/oa_tc6.h
+++ b/include/linux/oa_tc6.h
@@ -21,3 +21,4 @@ int oa_tc6_read_register(struct oa_tc6 *tc6, u32 address, u32 *value);
 int oa_tc6_read_registers(struct oa_tc6 *tc6, u32 address, u32 value[],
 			  u8 length);
 netdev_tx_t oa_tc6_start_xmit(struct oa_tc6 *tc6, struct sk_buff *skb);
+int oa_tc6_zero_align_receive_frame_enable(struct oa_tc6 *tc6);
-- 
2.34.1