net: fec: fix MDIO bus assignement for dual fec SoC's

On i.MX28, the MDIO bus is shared between the two FEC instances.
The driver makes sure that the second FEC uses the MDIO bus of the
first FEC. This is done conditionally if FEC_QUIRK_ENET_MAC is set.
However, in newer designs, such as Vybrid or i.MX6SX, each FEC MAC
has its own MDIO bus. Simply removing the quirk FEC_QUIRK_ENET_MAC
is not an option since other logic, triggered by this quirk, is
still needed.

Furthermore, there are board designs which use the same MDIO bus
for both PHY's even though the second bus would be available on the
SoC side. Such layout are popular since it saves pins on SoC side.
Due to the above quirk, those boards currently do work fine. The
boards in the mainline tree with such a layout are:
- Freescale Vybrid Tower with TWR-SER2 (vf610-twr.dts)
- Freescale i.MX6 SoloX SDB Board (imx6sx-sdb.dts)

This patch adds a new quirk FEC_QUIRK_SINGLE_MDIO for i.MX28, which
makes sure that the MDIO bus of the first FEC is used in any case.

However, the boards above do have a SoC with a MDIO bus for each FEC
instance. But the PHY's are not connected in a 1:1 configuration. A
proper device tree description is needed to allow the driver to
figure out where to find its PHY. This patch fixes that shortcoming
by adding a MDIO bus child node to the first FEC instance, along
with the two PHY's on that bus, and making use of the phy-handle
property to add a reference to the PHY's.

Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/arch/arm/boot/dts/imx6sx-sdb.dts b/arch/arm/boot/dts/imx6sx-sdb.dts
index 1e6e5cc1c14cf283fb8b3bd9321f44218fbe4fb3..8c1febd7e3f2757176d1ba0ab14450133010d177 100644 (file)
--- a/arch/arm/boot/dts/imx6sx-sdb.dts
+++ b/arch/arm/boot/dts/imx6sx-sdb.dts
@@ -159,13 +159,28 @@
        pinctrl-0 = <&pinctrl_enet1>;
        phy-supply = <&reg_enet_3v3>;
        phy-mode = "rgmii";
+       phy-handle = <&ethphy1>;
        status = "okay";
+
+       mdio {
+               #address-cells = <1>;
+               #size-cells = <0>;
+
+               ethphy1: ethernet-phy@0 {
+                       reg = <0>;
+               };
+
+               ethphy2: ethernet-phy@1 {
+                       reg = <1>;
+               };
+       };
 };
 
 &fec2 {
        pinctrl-names = "default";
        pinctrl-0 = <&pinctrl_enet2>;
        phy-mode = "rgmii";
+       phy-handle = <&ethphy2>;
        status = "okay";
 };
 

diff --git a/arch/arm/boot/dts/vf610-twr.dts b/arch/arm/boot/dts/vf610-twr.dts
index a0f762159cb26501b517a1af0d529da8abc42283..f2b64b1b00fa5231fc2493164fcc89f434687cd1 100644 (file)
--- a/arch/arm/boot/dts/vf610-twr.dts
+++ b/arch/arm/boot/dts/vf610-twr.dts
@@ -129,13 +129,28 @@
 
 &fec0 {
        phy-mode = "rmii";
+       phy-handle = <&ethphy0>;
        pinctrl-names = "default";
        pinctrl-0 = <&pinctrl_fec0>;
        status = "okay";
+
+       mdio {
+               #address-cells = <1>;
+               #size-cells = <0>;
+
+               ethphy0: ethernet-phy@0 {
+                       reg = <0>;
+               };
+
+               ethphy1: ethernet-phy@1 {
+                       reg = <1>;
+               };
+       };
 };
 
 &fec1 {
        phy-mode = "rmii";
+       phy-handle = <&ethphy1>;
        pinctrl-names = "default";
        pinctrl-0 = <&pinctrl_fec1>;
        status = "okay";

diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h
index 469691ad4a1ee25dda5ff9dbec0ef8735ae0f6bf..40132929daf7ac7713f2cd0f1f469656616fadfc 100644 (file)
--- a/drivers/net/ethernet/freescale/fec.h
+++ b/drivers/net/ethernet/freescale/fec.h
@@ -424,6 +424,8 @@ struct bufdesc_ex {
  * (40ns * 6).
  */
 #define FEC_QUIRK_BUG_CAPTURE          (1 << 10)
+/* Controller has only one MDIO bus */
+#define FEC_QUIRK_SINGLE_MDIO          (1 << 11)
 
 struct fec_enet_priv_tx_q {
        int index;

diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index dbcab1cecf68615ee203ceab32d73a3bd5cadfe7..bba87775419dc9c0d5adadcdda8c1e634dc8e04d 100644 (file)
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -91,7 +91,8 @@ static struct platform_device_id fec_devtype[] = {
                .driver_data = 0,
        }, {
                .name = "imx28-fec",
-               .driver_data = FEC_QUIRK_ENET_MAC | FEC_QUIRK_SWAP_FRAME,
+               .driver_data = FEC_QUIRK_ENET_MAC | FEC_QUIRK_SWAP_FRAME |
+                               FEC_QUIRK_SINGLE_MDIO,
        }, {
                .name = "imx6q-fec",
                .driver_data = FEC_QUIRK_ENET_MAC | FEC_QUIRK_HAS_GBIT |
@@ -1937,7 +1938,7 @@ static int fec_enet_mii_init(struct platform_device *pdev)
        int err = -ENXIO, i;
 
        /*
-        * The dual fec interfaces are not equivalent with enet-mac.
+        * The i.MX28 dual fec interfaces are not equal.
         * Here are the differences:
         *
         *  - fec0 supports MII & RMII modes while fec1 only supports RMII
@@ -1952,7 +1953,7 @@ static int fec_enet_mii_init(struct platform_device *pdev)
         * mdio interface in board design, and need to be configured by
         * fec0 mii_bus.
         */
-       if ((fep->quirks & FEC_QUIRK_ENET_MAC) && fep->dev_id > 0) {
+       if ((fep->quirks & FEC_QUIRK_SINGLE_MDIO) && fep->dev_id > 0) {
                /* fec1 uses fec0 mii_bus */
                if (mii_cnt && fec0_mii_bus) {
                        fep->mii_bus = fec0_mii_bus;
@@ -2015,7 +2016,7 @@ static int fec_enet_mii_init(struct platform_device *pdev)
        mii_cnt++;
 
        /* save fec0 mii_bus */
-       if (fep->quirks & FEC_QUIRK_ENET_MAC)
+       if (fep->quirks & FEC_QUIRK_SINGLE_MDIO)
                fec0_mii_bus = fep->mii_bus;
 
        return 0;