drivers: net: xgene: Add workaround for errata 10GE_1

This patch implements workaround for errata 10GE_1:
10Gb Ethernet port FIFO threshold default values are incorrect.

Signed-off-by: Quan Nguyen <qnguyen@apm.com>
Signed-off-by: Toan Le <toanle@apm.com>
Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Tested-by: Fushen Chen <fchen@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/apm/xgene/xgene_enet_xgmac.c

@@ -341,8 +341,15 @@ static void xgene_xgmac_init(struct xgene_enet_pdata *pdata)
 
 	xgene_enet_rd_csr(pdata, XG_RSIF_CONFIG_REG_ADDR, &data);
 	data |= CFG_RSIF_FPBUFF_TIMEOUT_EN;
+	/* Errata 10GE_1 - FIFO threshold default value incorrect */
+	RSIF_CLE_BUFF_THRESH_SET(&data, XG_RSIF_CLE_BUFF_THRESH);
 	xgene_enet_wr_csr(pdata, XG_RSIF_CONFIG_REG_ADDR, data);
 
+	/* Errata 10GE_1 - FIFO threshold default value incorrect */
+	xgene_enet_rd_csr(pdata, XG_RSIF_CONFIG1_REG_ADDR, &data);
+	RSIF_PLC_CLE_BUFF_THRESH_SET(&data, XG_RSIF_PLC_CLE_BUFF_THRESH);
+	xgene_enet_wr_csr(pdata, XG_RSIF_CONFIG1_REG_ADDR, data);
+
 	xgene_enet_rd_csr(pdata, XG_ENET_SPARE_CFG_REG_ADDR, &data);
 	data |= BIT(12);
 	xgene_enet_wr_csr(pdata, XG_ENET_SPARE_CFG_REG_ADDR, data);

drivers/net/ethernet/apm/xgene/xgene_enet_xgmac.h

@@ -65,6 +65,11 @@
 #define XG_DEF_PAUSE_THRES		0x390
 #define XG_DEF_PAUSE_OFF_THRES		0x2c0
 #define XG_RSIF_CONFIG_REG_ADDR		0x00a0
+#define XG_RSIF_CLE_BUFF_THRESH                0x3
+#define RSIF_CLE_BUFF_THRESH_SET(dst, val)     xgene_set_bits(dst, val, 0, 3)
+#define XG_RSIF_CONFIG1_REG_ADDR       0x00b8
+#define XG_RSIF_PLC_CLE_BUFF_THRESH    0x1
+#define RSIF_PLC_CLE_BUFF_THRESH_SET(dst, val) xgene_set_bits(dst, val, 0, 2)
 #define XCLE_BYPASS_REG0_ADDR           0x0160
 #define XCLE_BYPASS_REG1_ADDR           0x0164
 #define XG_CFG_BYPASS_ADDR		0x0204