Openwrt/target/linux/ramips/patches-5.4/991-at803x.patch

From 924453aa9d2324e5611f8e2b71df746d8f0c79f1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20van=20Dorst?= <opensource@vdorst.com>
Date: Fri, 13 Nov 2020 16:11:32 +0100
Subject: [PATCH] net: phy: at803x: add support for SFP module in
 RGMII-to-x-base mode
MIME-Version: 1.0
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Content-Transfer-Encoding: 8bit

Signed-off-by: René van Dorst <opensource@vdorst.com>
---
 drivers/net/phy/at803x.c | 91 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 91 insertions(+)

--- a/drivers/net/phy/at803x.c
+++ b/drivers/net/phy/at803x.c
@@ -14,6 +14,8 @@
 #include <linux/etherdevice.h>
 #include <linux/of_gpio.h>
 #include <linux/gpio/consumer.h>
+#include <linux/sfp.h>
+#include <linux/phylink.h>
 
 #define AT803X_SPECIFIC_STATUS			0x11
 #define AT803X_SS_SPEED_MASK			(3 << 14)
@@ -53,9 +55,18 @@
 
 #define AT803X_MODE_CFG_MASK			0x0F
 #define AT803X_MODE_CFG_SGMII			0x01
+#define AT803X_MODE_CFG_BX1000_RGMII_50		0x02
+#define AT803X_MODE_CFG_BX1000_RGMII_75		0x03
+#define AT803X_MODE_FIBER			0x01
+#define AT803X_MODE_COPPER			0x00
 
 #define AT803X_PSSR			0x11	/*PHY-Specific Status Register*/
 #define AT803X_PSSR_MR_AN_COMPLETE	0x0200
+#define	 PSSR_LINK			BIT(10)
+#define	 PSSR_SYNC_STATUS		BIT(8)
+#define	 PSSR_DUPLEX			BIT(13)
+#define	 PSSR_SPEED_1000		BIT(15)
+#define	 PSSR_SPEED_100			BIT(14)
 
 #define AT803X_DEBUG_REG_0			0x00
 #define AT803X_DEBUG_RX_CLK_DLY_EN		BIT(15)
@@ -243,10 +254,72 @@ static int at803x_resume(struct phy_devi
 	return phy_modify(phydev, MII_BMCR, BMCR_PDOWN | BMCR_ISOLATE, 0);
 }
 
+static int at803x_mode(struct phy_device *phydev)
+{
+	int mode;
+
+	mode = phy_read(phydev, AT803X_REG_CHIP_CONFIG) & AT803X_MODE_CFG_MASK;
+
+	if (mode == AT803X_MODE_CFG_BX1000_RGMII_50 ||
+	    mode == AT803X_MODE_CFG_BX1000_RGMII_75)
+		return AT803X_MODE_FIBER;
+	return AT803X_MODE_COPPER;
+}
+
+static int at803x_sfp_insert(void *upstream, const struct sfp_eeprom_id *id)
+{
+	__ETHTOOL_DECLARE_LINK_MODE_MASK(at803x_support) = { 0, };
+	__ETHTOOL_DECLARE_LINK_MODE_MASK(support) = { 0, };
+	struct phy_device *phydev = upstream;
+	phy_interface_t iface;
+
+	phylink_set(at803x_support, 1000baseX_Full);
+	/* AT803x only support 1000baseX but SGMII works fine when module runs
+	 * at 1Gbit.
+	 */
+	phylink_set(at803x_support, 1000baseT_Full);
+
+	sfp_parse_support(phydev->sfp_bus, id, support);
+
+	// Limit to interfaces that both sides support
+	linkmode_and(support, support, at803x_support);
+
+	if (linkmode_empty(support))
+		goto unsupported_mode;
+
+	iface = sfp_select_interface(phydev->sfp_bus, support);
+
+	if (iface != PHY_INTERFACE_MODE_SGMII &&
+	    iface != PHY_INTERFACE_MODE_1000BASEX)
+		goto unsupported_mode;
+
+	dev_info(&phydev->mdio.dev, "SFP interface %s", phy_modes(iface));
+
+	return 0;
+
+unsupported_mode:
+	dev_info(&phydev->mdio.dev, "incompatible SFP module inserted;"
+		 "Only SGMII at 1Gbit/1000BASEX are supported!\n");
+	return -EINVAL;
+}
+
+static const struct sfp_upstream_ops at803x_sfp_ops = {
+	.attach = phy_sfp_attach,
+	.detach = phy_sfp_detach,
+	.module_insert = at803x_sfp_insert,
+};
+
 static int at803x_probe(struct phy_device *phydev)
 {
 	struct device *dev = &phydev->mdio.dev;
 	struct at803x_priv *priv;
+	int ret;
+
+	if (at803x_mode(phydev) == AT803X_MODE_FIBER) {
+		ret = phy_sfp_probe(phydev, &at803x_sfp_ops);
+		if (ret < 0)
+			return ret;
+	}
 
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
@@ -394,6 +467,10 @@ static int at803x_read_status(struct phy
 {
 	int ss, err, old_link = phydev->link;
 
+	/* Handle (Fiber) SGMII to RGMII mode */
+	if (at803x_mode(phydev) == AT803X_MODE_FIBER)
+		return genphy_c37_read_status(phydev);
+
 	/* Update the link, but return if there was an error */
 	err = genphy_update_link(phydev);
 	if (err)
@@ -448,6 +525,19 @@ static int at803x_read_status(struct phy
 	return 0;
 }
 
+static int at803x_config_aneg(struct phy_device *phydev)
+{
+	/* Handle (Fiber) SerDes to RGMII mode */
+	if (at803x_mode(phydev) == AT803X_MODE_FIBER) {
+		pr_warn("%s: fiber\n", __func__);
+		return genphy_c37_config_aneg(phydev);
+	}
+
+	pr_warn("%s: enter\n", __func__);
+
+	return genphy_config_aneg(phydev);
+}
+
 static struct phy_driver at803x_driver[] = {
 {
 	/* ATHEROS 8035 */
@@ -491,6 +581,7 @@ static struct phy_driver at803x_driver[]
 	.suspend		= at803x_suspend,
 	.resume			= at803x_resume,
 	/* PHY_GBIT_FEATURES */
+	.config_aneg		= at803x_config_aneg,
 	.read_status		= at803x_read_status,
 	.aneg_done		= at803x_aneg_done,
 	.ack_interrupt		= &at803x_ack_interrupt,