ar71xx: fix 100/10mbps ethernet link issues on mynet range extender

The mynet range extender hardware is suffering from ethernet
link loss when booting with a recent openwrt image. This only
happens on 100mbps links, with 1Gbps speed the link was fine.

The cause of the problem is that the AR8035 PHY (aka F1E)
requires turning on and off the special TX delay setting
depending on the speed of the link.

The 10mbps mode only needed the proper pll value, which was
extracted from the vendor code.

Reported-by: Pascal Paradis
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>

SVN-Revision: 45954

target/linux/ar71xx/files/arch/mips/ath79/mach-mynet-rext.c

@@ -14,6 +14,7 @@
 #include <linux/platform_device.h>
 #include <linux/ath9k_platform.h>
 #include <linux/ar8216_platform.h>
+#include <linux/platform_data/phy-at803x.h>
 
 #include <asm/mach-ath79/ar71xx_regs.h>
 
@@ -124,6 +125,21 @@ static struct gpio_keys_button mynet_rext_gpio_keys[] __initdata = {
 	},
 };
 
+static struct at803x_platform_data mynet_rext_at803x_data = {
+	.disable_smarteee = 0,
+	.enable_rgmii_rx_delay = 1,
+	.enable_rgmii_tx_delay = 0,
+	.fixup_rgmii_tx_delay = 1,
+};
+
+static struct mdio_board_info mynet_rext_mdio0_info[] = {
+        {
+                .bus_id = "ag71xx-mdio.0",
+                .phy_addr = 4,
+                .platform_data = &mynet_rext_at803x_data,
+        },
+};
+
 static void mynet_rext_get_mac(const char *name, char *mac)
 {
 	u8 *nvram = (u8 *) KSEG1ADDR(MYNET_REXT_NVRAM_ADDR);
@@ -169,12 +185,16 @@ static void __init mynet_rext_setup(void)
 
 	ath79_register_mdio(0, 0x0);
 
+	mdiobus_register_board_info(mynet_rext_mdio0_info,
+				    ARRAY_SIZE(mynet_rext_mdio0_info));
+
 	/* LAN */
 	mynet_rext_get_mac("et0macaddr=", ath79_eth0_data.mac_addr);
 
 	/* GMAC0 is connected to an external PHY on Port 4 */
 	ath79_eth0_data.phy_if_mode = PHY_INTERFACE_MODE_RGMII;
 	ath79_eth0_data.phy_mask = BIT(4);
+	ath79_eth0_pll_data.pll_10   = 0x00001313; /* athrs_mac.c */
 	ath79_eth0_pll_data.pll_1000 = 0x0e000000; /* athrs_mac.c */
 	ath79_eth0_data.mii_bus_dev = &ath79_mdio0_device.dev;
 	ath79_register_eth(0);

target/linux/ar71xx/patches-3.18/425-net-phy-at803x-allow-to-configure-via-pdata.patch

@@ -32,6 +32,14 @@
  #define AT803X_DEBUG_SYSTEM_MODE_CTRL		0x05
  #define AT803X_DEBUG_RGMII_TX_CLK_DLY		BIT(8)
  
+@@ -50,6 +60,7 @@ MODULE_LICENSE("GPL");
+ struct at803x_priv {
+ 	bool phy_reset:1;
+ 	struct gpio_desc *gpiod_reset;
++	int prev_speed;
+ };
+ 
+ struct at803x_context {
 @@ -61,6 +71,43 @@ struct at803x_context {
  	u16 led_control;
  };
@@ -120,16 +128,53 @@
  	return 0;
  }
  
+@@ -258,6 +334,8 @@ static int at803x_config_intr(struct phy
+ static void at803x_link_change_notify(struct phy_device *phydev)
+ {
+ 	struct at803x_priv *priv = phydev->priv;
++	struct at803x_platform_data *pdata;
++	pdata = dev_get_platdata(&phydev->dev);
+ 
+ 	/*
+ 	 * Conduct a hardware reset for AT8030 every time a link loss is
+@@ -287,6 +365,26 @@ static void at803x_link_change_notify(st
+ 		} else {
+ 			priv->phy_reset = false;
+ 		}
++	}
++	if (pdata->fixup_rgmii_tx_delay &&
++	    phydev->speed != priv->prev_speed) {
++		switch (phydev->speed) {
++		case SPEED_10:
++		case SPEED_100:
++			at803x_dbg_reg_set(phydev,
++				AT803X_DEBUG_SYSTEM_MODE_CTRL,
++				AT803X_DEBUG_RGMII_TX_CLK_DLY);
++			break;
++		case SPEED_1000:
++			at803x_dbg_reg_clr(phydev,
++				AT803X_DEBUG_SYSTEM_MODE_CTRL,
++				AT803X_DEBUG_RGMII_TX_CLK_DLY);
++			break;
++		default:
++			break;
++		}
++
++		priv->prev_speed = phydev->speed;
+ 	}
+ }
+ 
 --- /dev/null
 +++ b/include/linux/platform_data/phy-at803x.h
-@@ -0,0 +1,10 @@
+@@ -0,0 +1,11 @@
 +#ifndef _PHY_AT803X_PDATA_H
 +#define _PHY_AT803X_PDATA_H
 +
 +struct at803x_platform_data {
-+       int disable_smarteee:1;
-+       int enable_rgmii_tx_delay:1;
-+       int enable_rgmii_rx_delay:1;
++	int disable_smarteee:1;
++	int enable_rgmii_tx_delay:1;
++	int enable_rgmii_rx_delay:1;
++	int fixup_rgmii_tx_delay:1;
 +};
 +
 +#endif /* _PHY_AT803X_PDATA_H */