releases/5.16.5/net-stmmac-dwmac-visconti-fix-clock-configuration-fo.patch

From fb16a6e0a5f2ca8a93f597b4ba62ee1006d7408b Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Wed, 19 Jan 2022 13:46:48 +0900
Subject: net: stmmac: dwmac-visconti: Fix clock configuration for RMII mode

From: Yuji Ishikawa <yuji2.ishikawa@toshiba.co.jp>

[ Upstream commit 0959bc4bd4206433ed101a1332a23e93ad16ec77 ]

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: b38dd98ff8d0 ("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>
---
 .../ethernet/stmicro/stmmac/dwmac-visconti.c  | 32 ++++++++++++-------
 1 file changed, 21 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-visconti.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-visconti.c
index 43a446ceadf7a..dde5b772a5af7 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-visconti.c
+++ b/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);
 }
 
-- 
2.34.1