bnx2x: Fix 578xx-KR 1G link

Fix a problem where 578xx-KR is unable to get link when connected to 1G link
partner. Two fixes were required:
One was to force CL37 sync_status low to prevent Warpcore from getting stuck in
CL73 parallel detect loop while link partner is sending.
Second fix was to enable auto-detect mode, thus allowing the Warpcore to select
the higher speed protocol between 10G-KR (over CL73), or go down to 1G over CL73
when there's indication for it.
Signed-off-by: Yaniv Rosner <yanivr@broadcom.com>
Signed-off-by: Ariel Elior <ariele@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c

@@ -3865,6 +3865,19 @@ static void bnx2x_warpcore_enable_AN_KR(struct bnx2x_phy *phy,
 
 		bnx2x_warpcore_enable_AN_KR2(phy, params, vars);
 	} else {
+		/* Enable Auto-Detect to support 1G over CL37 as well */
+		bnx2x_cl45_write(bp, phy, MDIO_WC_DEVAD,
+				 MDIO_WC_REG_SERDESDIGITAL_CONTROL1000X1, 0x10);
+
+		/* Force cl48 sync_status LOW to avoid getting stuck in CL73
+		 * parallel-detect loop when CL73 and CL37 are enabled.
+		 */
+		CL22_WR_OVER_CL45(bp, phy, MDIO_REG_BANK_AER_BLOCK,
+				  MDIO_AER_BLOCK_AER_REG, 0);
+		bnx2x_cl45_write(bp, phy, MDIO_WC_DEVAD,
+				 MDIO_WC_REG_RXB_ANA_RX_CONTROL_PCI, 0x0800);
+		bnx2x_set_aer_mmd(params, phy);
+
 		bnx2x_disable_kr2(params, vars, phy);
 	}
 

drivers/net/ethernet/broadcom/bnx2x/bnx2x_reg.h

@@ -7179,6 +7179,7 @@ Theotherbitsarereservedandshouldbezero*/
 #define MDIO_WC_REG_RX1_PCI_CTRL			0x80ca
 #define MDIO_WC_REG_RX2_PCI_CTRL			0x80da
 #define MDIO_WC_REG_RX3_PCI_CTRL			0x80ea
+#define MDIO_WC_REG_RXB_ANA_RX_CONTROL_PCI		0x80fa
 #define MDIO_WC_REG_XGXSBLK2_UNICORE_MODE_10G		0x8104
 #define MDIO_WC_REG_XGXS_STATUS3			0x8129
 #define MDIO_WC_REG_PAR_DET_10G_STATUS			0x8130