net: phy: bcm54811: Fix GMII/MII/MII-Lite selection

Software RGMII - GMII/MII/MII-Lite selection.

The bcm54811 PHY needs this bit to be configured in addition to hardware strapping of the PHY chip to desired mode.

This configuration step got lost during the refining of previous patch.

Changes in v2:
- Applied reviewers' comments
- Not setting RGMII RXD to RXC Skew in non-RGMII mode

Changes in v3:
- Specified target tree name

Kamil Horák - 2N (1):
net: phy: bcm54811: Fix GMII/MII/MII-Lite selection

 drivers/net/phy/broadcom.c | 20 +++++++++++++++++++-
 include/linux/brcmphy.h    |  1 +
 2 files changed, 20 insertions(+), 1 deletion(-)

2.39.5

The Broadcom bcm54811 is hardware-strapped to select among RGMII and GMII/MII/MII-Lite modes. However, the corresponding bit, RGMII Enable in Miscellaneous Control Register must be also set to select desired RGMII or MII(-lite)/GMII mode.

---
 drivers/net/phy/broadcom.c | 20 +++++++++++++++++++-
 include/linux/brcmphy.h    |  1 +
 2 files changed, 20 insertions(+), 1 deletion(-)

index 3459a0e9d8b9..cb306f9e80cc 100644
@@ -405,7 +405,7 @@ static int bcm5481x_set_brrmode(struct phy_device *phydev, bool on)
 static int bcm54811_config_init(struct phy_device *phydev)
 {
 	struct bcm54xx_phy_priv *priv = phydev->priv;
-	int err, reg, exp_sync_ethernet;
+	int err, reg, exp_sync_ethernet, aux_rgmii_en;
 
 	/* Enable CLK125 MUX on LED4 if ref clock is enabled. */
 	if (!(phydev->dev_flags & PHY_BRCM_RX_REFCLK_UNUSED)) {

@@ -434,6 +434,24 @@ static int bcm54811_config_init(struct phy_device *phydev)
 	if (err < 0)
 		return err;
 
+	/* Enable RGMII if configured */
+	if (phy_interface_is_rgmii(phydev))
+		aux_rgmii_en = MII_BCM54XX_AUXCTL_SHDWSEL_MISC_RGMII_EN |
+			       MII_BCM54XX_AUXCTL_SHDWSEL_MISC_RGMII_SKEW_EN;
+	else
+		aux_rgmii_en = 0;
+
+	/* Also writing Reserved bits 6:5 because the documentation requires
+	 * them to be written to 0b11
+	 */
+	err = bcm54xx_auxctl_write(phydev,
+				   MII_BCM54XX_AUXCTL_SHDWSEL_MISC,
+				   MII_BCM54XX_AUXCTL_MISC_WREN |
+				   aux_rgmii_en |
+				   MII_BCM54XX_AUXCTL_SHDWSEL_MISC_RSVD);
+	if (err < 0)
+		return err;
+
 	return bcm5481x_set_brrmode(phydev, priv->brr_mode);
 }
 

index 15c35655f482..115a964f3006 100644
@@ -137,6 +137,7 @@
 
 #define MII_BCM54XX_AUXCTL_SHDWSEL_MISC			0x07
 #define MII_BCM54XX_AUXCTL_SHDWSEL_MISC_WIRESPEED_EN	0x0010
+#define MII_BCM54XX_AUXCTL_SHDWSEL_MISC_RSVD		0x0060
 #define MII_BCM54XX_AUXCTL_SHDWSEL_MISC_RGMII_EN	0x0080
 #define MII_BCM54XX_AUXCTL_SHDWSEL_MISC_RGMII_SKEW_EN	0x0100
 #define MII_BCM54XX_AUXCTL_MISC_FORCE_AMDIX		0x0200

2.39.5

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