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[PATCH net-next 2/2] net: lan743x: add support for RMII interface

Thangaraj Samynathan posted 2 patches 6 days, 11 hours ago
[PATCH net-next 2/2] net: lan743x: add support for RMII interface
Posted by Thangaraj Samynathan 6 days, 11 hours ago 
Enable RMII interface in the lan743x driver for PHY and MAC
configuration.

- Select RMII interface in lan743x_phy_interface_select().
- Update phylink supported_interfaces and MAC capabilities.
- Enable RMII via RMII_CTL in lan743x_hardware_init().
- Define RMII_CTL register and enable bit in lan743x_main.h.

Signed-off-by: Thangaraj Samynathan <thangaraj.s@microchip.com>
---
 drivers/net/ethernet/microchip/lan743x_main.c | 18 ++++++++++++++++++
 drivers/net/ethernet/microchip/lan743x_main.h |  3 +++
 2 files changed, 21 insertions(+)

diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
index b7b1584d867d..86d35810460f 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.c
+++ b/drivers/net/ethernet/microchip/lan743x_main.c
@@ -1370,6 +1370,8 @@ static void lan743x_phy_interface_select(struct lan743x_adapter *adapter)
 
 	if (adapter->is_pci11x1x && adapter->is_sgmii_en)
 		adapter->phy_interface = PHY_INTERFACE_MODE_SGMII;
+	else if (adapter->is_pci11x1x && adapter->is_rmii_en)
+		adapter->phy_interface = PHY_INTERFACE_MODE_RMII;
 	else if (id_rev == ID_REV_ID_LAN7430_)
 		adapter->phy_interface = PHY_INTERFACE_MODE_GMII;
 	else if ((id_rev == ID_REV_ID_LAN7431_) && (data & MAC_CR_MII_EN_))
@@ -3158,6 +3160,13 @@ static int lan743x_phylink_create(struct lan743x_adapter *adapter)
 		__set_bit(PHY_INTERFACE_MODE_MII,
 			  adapter->phylink_config.supported_interfaces);
 		break;
+	case PHY_INTERFACE_MODE_RMII:
+		__set_bit(PHY_INTERFACE_MODE_RMII,
+			  adapter->phylink_config.supported_interfaces);
+		adapter->phylink_config.mac_capabilities &= ~MAC_1000FD;
+		adapter->phylink_config.lpi_capabilities = 0;
+		break;
+
 	default:
 		phy_interface_set_rgmii(adapter->phylink_config.supported_interfaces);
 	}
@@ -3165,6 +3174,9 @@ static int lan743x_phylink_create(struct lan743x_adapter *adapter)
 	memcpy(adapter->phylink_config.lpi_interfaces,
 	       adapter->phylink_config.supported_interfaces,
 	       sizeof(adapter->phylink_config.lpi_interfaces));
+	if (adapter->phy_interface == PHY_INTERFACE_MODE_RMII)
+		__clear_bit(PHY_INTERFACE_MODE_RMII,
+			    adapter->phylink_config.lpi_interfaces);
 
 	pl = phylink_create(&adapter->phylink_config, NULL,
 			    adapter->phy_interface, &lan743x_phylink_mac_ops);
@@ -3509,6 +3521,7 @@ static int lan743x_hardware_init(struct lan743x_adapter *adapter,
 {
 	struct lan743x_tx *tx;
 	u32 sgmii_ctl;
+	u32 rmii_ctl;
 	int index;
 	int ret;
 
@@ -3530,6 +3543,11 @@ static int lan743x_hardware_init(struct lan743x_adapter *adapter,
 			sgmii_ctl |= SGMII_CTL_SGMII_POWER_DN_;
 		}
 		lan743x_csr_write(adapter, SGMII_CTL, sgmii_ctl);
+		if (adapter->is_rmii_en) {
+			rmii_ctl = lan743x_csr_read(adapter, RMII_CTL);
+			rmii_ctl |= RMII_CTL_RMII_ENABLE_;
+			lan743x_csr_write(adapter, RMII_CTL, rmii_ctl);
+		}
 	} else {
 		adapter->max_tx_channels = LAN743X_MAX_TX_CHANNELS;
 		adapter->used_tx_channels = LAN743X_USED_TX_CHANNELS;
diff --git a/drivers/net/ethernet/microchip/lan743x_main.h b/drivers/net/ethernet/microchip/lan743x_main.h
index 1d7d37456553..03f3727ed8f7 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.h
+++ b/drivers/net/ethernet/microchip/lan743x_main.h
@@ -324,6 +324,9 @@
 #define MAC_WUCSR2_IPV6_TCPSYN_RCD_	BIT(5)
 #define MAC_WUCSR2_IPV4_TCPSYN_RCD_	BIT(4)
 
+#define RMII_CTL			(0x710)
+#define RMII_CTL_RMII_ENABLE_		BIT(0)
+
 #define SGMII_ACC			(0x720)
 #define SGMII_ACC_SGMII_BZY_		BIT(31)
 #define SGMII_ACC_SGMII_WR_		BIT(30)
-- 
2.34.1
Re: [PATCH net-next 2/2] net: lan743x: add support for RMII interface
Posted by Russell King (Oracle) 6 days, 8 hours ago 
On Fri, Mar 27, 2026 at 11:10:08AM +0530, Thangaraj Samynathan wrote:
> Enable RMII interface in the lan743x driver for PHY and MAC
> configuration.
> 
> - Select RMII interface in lan743x_phy_interface_select().
> - Update phylink supported_interfaces and MAC capabilities.
> - Enable RMII via RMII_CTL in lan743x_hardware_init().
> - Define RMII_CTL register and enable bit in lan743x_main.h.
> 
> Signed-off-by: Thangaraj Samynathan <thangaraj.s@microchip.com>
> ---
>  drivers/net/ethernet/microchip/lan743x_main.c | 18 ++++++++++++++++++
>  drivers/net/ethernet/microchip/lan743x_main.h |  3 +++
>  2 files changed, 21 insertions(+)
> 
> diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
> index b7b1584d867d..86d35810460f 100644
> --- a/drivers/net/ethernet/microchip/lan743x_main.c
> +++ b/drivers/net/ethernet/microchip/lan743x_main.c
> @@ -1370,6 +1370,8 @@ static void lan743x_phy_interface_select(struct lan743x_adapter *adapter)
>  
>  	if (adapter->is_pci11x1x && adapter->is_sgmii_en)
>  		adapter->phy_interface = PHY_INTERFACE_MODE_SGMII;
> +	else if (adapter->is_pci11x1x && adapter->is_rmii_en)
> +		adapter->phy_interface = PHY_INTERFACE_MODE_RMII;
>  	else if (id_rev == ID_REV_ID_LAN7430_)
>  		adapter->phy_interface = PHY_INTERFACE_MODE_GMII;
>  	else if ((id_rev == ID_REV_ID_LAN7431_) && (data & MAC_CR_MII_EN_))
> @@ -3158,6 +3160,13 @@ static int lan743x_phylink_create(struct lan743x_adapter *adapter)
>  		__set_bit(PHY_INTERFACE_MODE_MII,
>  			  adapter->phylink_config.supported_interfaces);
>  		break;
> +	case PHY_INTERFACE_MODE_RMII:
> +		__set_bit(PHY_INTERFACE_MODE_RMII,
> +			  adapter->phylink_config.supported_interfaces);
> +		adapter->phylink_config.mac_capabilities &= ~MAC_1000FD;

Phylink already knows that gigabit isn't supported with RMII. See
phy_caps_from_interface():

        case PHY_INTERFACE_MODE_REVRMII:
        case PHY_INTERFACE_MODE_RMII:
        case PHY_INTERFACE_MODE_SMII:
        case PHY_INTERFACE_MODE_REVMII:
        case PHY_INTERFACE_MODE_MII:
                link_caps |= BIT(LINK_CAPA_10HD) | BIT(LINK_CAPA_10FD);
                fallthrough;

        case PHY_INTERFACE_MODE_100BASEX:
                link_caps |= BIT(LINK_CAPA_100HD) | BIT(LINK_CAPA_100FD);
                break;

which is used by phylink_get_capabilities() to reduce the MAC
capabilities depending on the interface and rate matching.

The only case to do this is where the MAC really has no 1G support.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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Re: [PATCH net-next 2/2] net: lan743x: add support for RMII interface
Posted by Maxime Chevallier 6 days, 8 hours ago 
Hi,

On 27/03/2026 06:40, Thangaraj Samynathan wrote:
> Enable RMII interface in the lan743x driver for PHY and MAC
> configuration.
> 
> - Select RMII interface in lan743x_phy_interface_select().
> - Update phylink supported_interfaces and MAC capabilities.
> - Enable RMII via RMII_CTL in lan743x_hardware_init().
> - Define RMII_CTL register and enable bit in lan743x_main.h.
> 
> Signed-off-by: Thangaraj Samynathan <thangaraj.s@microchip.com>
> ---
>  drivers/net/ethernet/microchip/lan743x_main.c | 18 ++++++++++++++++++
>  drivers/net/ethernet/microchip/lan743x_main.h |  3 +++
>  2 files changed, 21 insertions(+)
> 
> diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
> index b7b1584d867d..86d35810460f 100644
> --- a/drivers/net/ethernet/microchip/lan743x_main.c
> +++ b/drivers/net/ethernet/microchip/lan743x_main.c
> @@ -1370,6 +1370,8 @@ static void lan743x_phy_interface_select(struct lan743x_adapter *adapter)
>  
>  	if (adapter->is_pci11x1x && adapter->is_sgmii_en)
>  		adapter->phy_interface = PHY_INTERFACE_MODE_SGMII;
> +	else if (adapter->is_pci11x1x && adapter->is_rmii_en)
> +		adapter->phy_interface = PHY_INTERFACE_MODE_RMII;
>  	else if (id_rev == ID_REV_ID_LAN7430_)
>  		adapter->phy_interface = PHY_INTERFACE_MODE_GMII;
>  	else if ((id_rev == ID_REV_ID_LAN7431_) && (data & MAC_CR_MII_EN_))
> @@ -3158,6 +3160,13 @@ static int lan743x_phylink_create(struct lan743x_adapter *adapter)
>  		__set_bit(PHY_INTERFACE_MODE_MII,
>  			  adapter->phylink_config.supported_interfaces);
>  		break;
> +	case PHY_INTERFACE_MODE_RMII:
> +		__set_bit(PHY_INTERFACE_MODE_RMII,
> +			  adapter->phylink_config.supported_interfaces);
> +		adapter->phylink_config.mac_capabilities &= ~MAC_1000FD;

Some followup should take care of removing the 1000FD cap for MII as
well. Same for the LPI caps, is there a similiar limitation for MII ?

Otherwise, this patch looks good to me so,

Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>	

Maxime
Re: [PATCH net-next 2/2] net: lan743x: add support for RMII interface
Posted by Maxime Chevallier 6 days, 7 hours ago 

On 27/03/2026 09:47, Maxime Chevallier wrote:
> Hi,
> 
> On 27/03/2026 06:40, Thangaraj Samynathan wrote:
>> Enable RMII interface in the lan743x driver for PHY and MAC
>> configuration.
>>
>> - Select RMII interface in lan743x_phy_interface_select().
>> - Update phylink supported_interfaces and MAC capabilities.
>> - Enable RMII via RMII_CTL in lan743x_hardware_init().
>> - Define RMII_CTL register and enable bit in lan743x_main.h.
>>
>> Signed-off-by: Thangaraj Samynathan <thangaraj.s@microchip.com>
>> ---
>>  drivers/net/ethernet/microchip/lan743x_main.c | 18 ++++++++++++++++++
>>  drivers/net/ethernet/microchip/lan743x_main.h |  3 +++
>>  2 files changed, 21 insertions(+)
>>
>> diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
>> index b7b1584d867d..86d35810460f 100644
>> --- a/drivers/net/ethernet/microchip/lan743x_main.c
>> +++ b/drivers/net/ethernet/microchip/lan743x_main.c
>> @@ -1370,6 +1370,8 @@ static void lan743x_phy_interface_select(struct lan743x_adapter *adapter)
>>  
>>  	if (adapter->is_pci11x1x && adapter->is_sgmii_en)
>>  		adapter->phy_interface = PHY_INTERFACE_MODE_SGMII;
>> +	else if (adapter->is_pci11x1x && adapter->is_rmii_en)
>> +		adapter->phy_interface = PHY_INTERFACE_MODE_RMII;
>>  	else if (id_rev == ID_REV_ID_LAN7430_)
>>  		adapter->phy_interface = PHY_INTERFACE_MODE_GMII;
>>  	else if ((id_rev == ID_REV_ID_LAN7431_) && (data & MAC_CR_MII_EN_))
>> @@ -3158,6 +3160,13 @@ static int lan743x_phylink_create(struct lan743x_adapter *adapter)
>>  		__set_bit(PHY_INTERFACE_MODE_MII,
>>  			  adapter->phylink_config.supported_interfaces);
>>  		break;
>> +	case PHY_INTERFACE_MODE_RMII:
>> +		__set_bit(PHY_INTERFACE_MODE_RMII,
>> +			  adapter->phylink_config.supported_interfaces);
>> +		adapter->phylink_config.mac_capabilities &= ~MAC_1000FD;
> 
> Some followup should take care of removing the 1000FD cap for MII as
> well.

Well as Russell says, no need for that :)


Maxime

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