net: stmmac: dwmac-visconti: Fix clock configuration for RMII mode

[ Upstream commit 0959bc4 ]

Bit pattern of the ETHER_CLOCK_SEL register for RMII/MII mode should be fixed.
Also, some control bits should be modified with a specific sequence.

Fixes: b38dd98 ("net: stmmac: Add Toshiba Visconti SoCs glue driver")
Signed-off-by: Yuji Ishikawa <yuji2.ishikawa@toshiba.co.jp>
Reviewed-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/net/ethernet/stmicro/stmmac/dwmac-visconti.c

@@ -96,31 +96,41 @@ static void visconti_eth_fix_mac_speed(void *priv, unsigned int speed)
 	val |= ETHER_CLK_SEL_TX_O_E_N_IN;
 	writel(val, dwmac->reg + REG_ETHER_CLOCK_SEL);
 
+	/* Set Clock-Mux, Start clock, Set TX_O direction */
 	switch (dwmac->phy_intf_sel) {
 	case ETHER_CONFIG_INTF_RGMII:
 		val = clk_sel_val | ETHER_CLK_SEL_RX_CLK_EXT_SEL_RXC;
+		writel(val, dwmac->reg + REG_ETHER_CLOCK_SEL);
+
+		val |= ETHER_CLK_SEL_RX_TX_CLK_EN;
+		writel(val, dwmac->reg + REG_ETHER_CLOCK_SEL);
+
+		val &= ~ETHER_CLK_SEL_TX_O_E_N_IN;
+		writel(val, dwmac->reg + REG_ETHER_CLOCK_SEL);
 		break;
 	case ETHER_CONFIG_INTF_RMII:
 		val = clk_sel_val | ETHER_CLK_SEL_RX_CLK_EXT_SEL_DIV |
-			ETHER_CLK_SEL_TX_CLK_EXT_SEL_TXC | ETHER_CLK_SEL_TX_O_E_N_IN |
+			ETHER_CLK_SEL_TX_CLK_EXT_SEL_DIV | ETHER_CLK_SEL_TX_O_E_N_IN |
 			ETHER_CLK_SEL_RMII_CLK_SEL_RX_C;
+		writel(val, dwmac->reg + REG_ETHER_CLOCK_SEL);
+
+		val |= ETHER_CLK_SEL_RMII_CLK_RST;
+		writel(val, dwmac->reg + REG_ETHER_CLOCK_SEL);
+
+		val |= ETHER_CLK_SEL_RMII_CLK_EN | ETHER_CLK_SEL_RX_TX_CLK_EN;
+		writel(val, dwmac->reg + REG_ETHER_CLOCK_SEL);
 		break;
 	case ETHER_CONFIG_INTF_MII:
 	default:
 		val = clk_sel_val | ETHER_CLK_SEL_RX_CLK_EXT_SEL_RXC |
-			ETHER_CLK_SEL_TX_CLK_EXT_SEL_DIV | ETHER_CLK_SEL_TX_O_E_N_IN |
-			ETHER_CLK_SEL_RMII_CLK_EN;
+			ETHER_CLK_SEL_TX_CLK_EXT_SEL_TXC | ETHER_CLK_SEL_TX_O_E_N_IN;
+		writel(val, dwmac->reg + REG_ETHER_CLOCK_SEL);
+
+		val |= ETHER_CLK_SEL_RX_TX_CLK_EN;
+		writel(val, dwmac->reg + REG_ETHER_CLOCK_SEL);
 		break;
 	}
 
-	/* Start clock */
-	writel(val, dwmac->reg + REG_ETHER_CLOCK_SEL);
-	val |= ETHER_CLK_SEL_RX_TX_CLK_EN;
-	writel(val, dwmac->reg + REG_ETHER_CLOCK_SEL);
-
-	val &= ~ETHER_CLK_SEL_TX_O_E_N_IN;
-	writel(val, dwmac->reg + REG_ETHER_CLOCK_SEL);
-
 	spin_unlock_irqrestore(&dwmac->lock, flags);
 }