net: dsa: mt7530: store port 5 SGMII capability of MT7531

Introduce the p5_sgmii field to store the information for whether port 5
has got SGMII or not. Instead of reading the MT7531_TOP_SIG_SR register
multiple times, the register will be read once and the value will be
stored on the p5_sgmii field. This saves unnecessary reads of the
register.

Move the comment about MT7531AE and MT7531BE to mt7531_setup(), where the
switch is identified.

Get rid of mt7531_dual_sgmii_supported() now that priv->p5_sgmii stores the
information. Address the code where mt7531_dual_sgmii_supported() is used.

Get rid of mt7531_is_rgmii_port() which just prints the opposite of
priv->p5_sgmii.

Instead of calling mt7531_pll_setup() then returning, do not call it if
port 5 is SGMII.

Remove P5_INTF_SEL_GMAC5_SGMII. The p5_interface_select enum is supposed to
represent the mode that port 5 is being used in, not the hardware
information of port 5. Set p5_intf_sel to P5_INTF_SEL_GMAC5 instead, if
port 5 is not dsa_is_unused_port().

Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
Acked-by: Daniel Golle <daniel@makrotopia.org>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20240122-for-netnext-mt7530-improvements-1-v3-3-042401f2b279@arinc9.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 16 insertions, 32 deletions

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index b282e526d709..cf61ff16f9aa 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -487,15 +487,6 @@ mt7530_pad_clk_setup(struct dsa_switch *ds, phy_interface_t interface)
 	return 0;
 }
 
-static bool mt7531_dual_sgmii_supported(struct mt7530_priv *priv)
-{
-	u32 val;
-
-	val = mt7530_read(priv, MT7531_TOP_SIG_SR);
-
-	return (val & PAD_DUAL_SGMII_EN) != 0;
-}
-
 static int
 mt7531_pad_setup(struct dsa_switch *ds, phy_interface_t interface)
 {
@@ -510,9 +501,6 @@ mt7531_pll_setup(struct mt7530_priv *priv)
 	u32 xtal;
 	u32 val;
 
-	if (mt7531_dual_sgmii_supported(priv))
-		return;
-
 	val = mt7530_read(priv, MT7531_CREV);
 	top_sig = mt7530_read(priv, MT7531_TOP_SIG_SR);
 	hwstrap = mt7530_read(priv, MT7531_HWTRAP);
@@ -920,8 +908,6 @@ static const char *p5_intf_modes(unsigned int p5_interface)
 		return "PHY P4";
 	case P5_INTF_SEL_GMAC5:
 		return "GMAC5";
-	case P5_INTF_SEL_GMAC5_SGMII:
-		return "GMAC5_SGMII";
 	default:
 		return "unknown";
 	}
@@ -2488,6 +2474,12 @@ mt7531_setup(struct dsa_switch *ds)
 		return -ENODEV;
 	}
 
+	/* MT7531AE has got two SGMII units. One for port 5, one for port 6.
+	 * MT7531BE has got only one SGMII unit which is for port 6.
+	 */
+	val = mt7530_read(priv, MT7531_TOP_SIG_SR);
+	priv->p5_sgmii = !!(val & PAD_DUAL_SGMII_EN);
+
 	/* all MACs must be forced link-down before sw reset */
 	for (i = 0; i < MT7530_NUM_PORTS; i++)
 		mt7530_write(priv, MT7530_PMCR_P(i), MT7531_FORCE_LNK);
@@ -2497,21 +2489,18 @@ mt7531_setup(struct dsa_switch *ds)
 		     SYS_CTRL_PHY_RST | SYS_CTRL_SW_RST |
 		     SYS_CTRL_REG_RST);
 
-	mt7531_pll_setup(priv);
-
-	if (mt7531_dual_sgmii_supported(priv)) {
-		priv->p5_intf_sel = P5_INTF_SEL_GMAC5_SGMII;
-
+	if (!priv->p5_sgmii) {
+		mt7531_pll_setup(priv);
+	} else {
 		/* Let ds->user_mii_bus be able to access external phy. */
 		mt7530_rmw(priv, MT7531_GPIO_MODE1, MT7531_GPIO11_RG_RXD2_MASK,
 			   MT7531_EXT_P_MDC_11);
 		mt7530_rmw(priv, MT7531_GPIO_MODE1, MT7531_GPIO12_RG_RXD3_MASK,
 			   MT7531_EXT_P_MDIO_12);
-	} else {
-		priv->p5_intf_sel = P5_INTF_SEL_GMAC5;
 	}
-	dev_dbg(ds->dev, "P5 support %s interface\n",
-		p5_intf_modes(priv->p5_intf_sel));
+
+	if (!dsa_is_unused_port(ds, 5))
+		priv->p5_intf_sel = P5_INTF_SEL_GMAC5;
 
 	mt7530_rmw(priv, MT7531_GPIO_MODE0, MT7531_GPIO0_MASK,
 		   MT7531_GPIO0_INTERRUPT);
@@ -2571,11 +2560,6 @@ static void mt7530_mac_port_get_caps(struct dsa_switch *ds, int port,
 	}
 }
 
-static bool mt7531_is_rgmii_port(struct mt7530_priv *priv, u32 port)
-{
-	return (port == 5) && (priv->p5_intf_sel != P5_INTF_SEL_GMAC5_SGMII);
-}
-
 static void mt7531_mac_port_get_caps(struct dsa_switch *ds, int port,
 				     struct phylink_config *config)
 {
@@ -2588,7 +2572,7 @@ static void mt7531_mac_port_get_caps(struct dsa_switch *ds, int port,
 		break;
 
 	case 5: /* 2nd cpu port supports either rgmii or sgmii/8023z */
-		if (mt7531_is_rgmii_port(priv, port)) {
+		if (!priv->p5_sgmii) {
 			phy_interface_set_rgmii(config->supported_interfaces);
 			break;
 		}
@@ -2655,7 +2639,7 @@ static int mt7531_rgmii_setup(struct mt7530_priv *priv, u32 port,
 {
 	u32 val;
 
-	if (!mt7531_is_rgmii_port(priv, port)) {
+	if (priv->p5_sgmii) {
 		dev_err(priv->dev, "RGMII mode is not available for port %d\n",
 			port);
 		return -EINVAL;
@@ -2899,7 +2883,7 @@ mt7531_cpu_port_config(struct dsa_switch *ds, int port)
 
 	switch (port) {
 	case 5:
-		if (mt7531_is_rgmii_port(priv, port))
+		if (!priv->p5_sgmii)
 			interface = PHY_INTERFACE_MODE_RGMII;
 		else
 			interface = PHY_INTERFACE_MODE_2500BASEX;
@@ -3051,7 +3035,7 @@ mt753x_setup(struct dsa_switch *ds)
 		mt7530_free_irq_common(priv);
 
 	if (priv->create_sgmii) {
-		ret = priv->create_sgmii(priv, mt7531_dual_sgmii_supported(priv));
+		ret = priv->create_sgmii(priv);
 		if (ret && priv->irq)
 			mt7530_free_irq(priv);
 	}