[PATCH v2 2/2] net: stmmac: dwmac-visconti: Fix clock configuration for RMII mode

From: Yuji Ishikawa
Date: Tue Jan 18 2022 - 23:54:09 EST


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@xxxxxxxxxxxxx>
Reviewed-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@xxxxxxxxxxxxx>
---
.../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 43a446cea..dde5b772a 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);
}

--
2.17.1