Subject: [PATCH,RFC] ep93xx_eth: conversion to phylib framework

From: Herbert Valerio Riedel <[email-masked]>
Date: Fri, 16 Nov 2007 10:38:20 +0100

Currently, the ep93xx_eth driver doesn't care about the PHY state,
but it should, in order to tell the MAC when full duplex operation is
required; failure to do so causes degraded performance on full duplex
links. This patch implements proper PHY handling via the phylib framework:

 - clean up ep93xx_mdio_{read,write} to conform to ep93xx manual
 - convert ep93xx_eth driver to phylib framework
 - set full duplex bit in configuration of MAC when FDX link detected
 - convert to use print_mac()

Signed-off-by: Herbert Valerio Riedel <[email-masked]>
Cc: Lennert Buytenhek <[email-masked]>
Cc: Andy Fleming <[email-masked]>
---
If you need me to split this patch, please let me know into 
what parts

 drivers/net/arm/Kconfig      |    1 +
 drivers/net/arm/ep93xx_eth.c |  354 +++++++++++++++++++++++++++++++++---------
 2 files changed, 282 insertions(+), 73 deletions(-)

diff --git a/drivers/net/arm/Kconfig b/drivers/net/arm/Kconfig
index f9cc2b6..5860175 100644
--- a/drivers/net/arm/Kconfig
+++ b/drivers/net/arm/Kconfig
@@ -44,6 +44,7 @@ config EP93XX_ETH
 	tristate "EP93xx Ethernet support"
 	depends on ARM && ARCH_EP93XX
 	select MII
+	select PHYLIB
 	help
 	  This is a driver for the ethernet hardware included in EP93xx CPUs.
 	  Say Y if you are building a kernel for EP93xx based devices.
diff --git a/drivers/net/arm/ep93xx_eth.c b/drivers/net/arm/ep93xx_eth.c
index 91a6590..6b9ac41 100644
--- a/drivers/net/arm/ep93xx_eth.c
+++ b/drivers/net/arm/ep93xx_eth.c
@@ -2,6 +2,7 @@
  * EP93xx ethernet network device driver
  * Copyright (C) 2006 Lennert Buytenhek <[email-masked]>
  * Dedicated to Marija Kulikova.
+ * Copyright (C) 2007 Herbert Valerio Riedel <[email-masked]>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -14,6 +15,7 @@
 #include <linux/kernel.h>
 #include <linux/netdevice.h>
 #include <linux/mii.h>
+#include <linux/phy.h>
 #include <linux/etherdevice.h>
 #include <linux/ethtool.h>
 #include <linux/init.h>
@@ -37,6 +39,8 @@
 #define  REG_RXCTL_DEFAULT	0x00073800
 #define REG_TXCTL		0x0004
 #define  REG_TXCTL_ENABLE	0x00000001
+#define REG_TESTCTL		0x0008
+#define  REG_TESTCTL_MFDX	0x00000040
 #define REG_MIICMD		0x0010
 #define  REG_MIICMD_READ	0x00008000
 #define  REG_MIICMD_WRITE	0x00004000
@@ -45,6 +49,9 @@
 #define  REG_MIISTS_BUSY	0x00000001
 #define REG_SELFCTL		0x0020
 #define  REG_SELFCTL_RESET	0x00000001
+#define  REG_SELFCTL_MDCDIV_MSK 0x00007e00
+#define  REG_SELFCTL_MDCDIV_OFS 9
+#define  REG_SELFCTL_PSPRS	0x00000100
 #define REG_INTEN		0x0024
 #define  REG_INTEN_TX		0x00000008
 #define  REG_INTEN_RX		0x00000007
@@ -174,8 +181,14 @@ struct ep93xx_priv
 
 	struct net_device_stats	stats;
 
-	struct mii_if_info	mii;
 	u8			mdc_divisor;
+	int			phy_supports_mfps:1;
+
+	struct mii_bus		mii_bus;
+	struct phy_device	*phy_dev;
+	int			speed;
+	int			duplex;
+	int			link;
 };
 
 #define rdb(ep, off)		__raw_readb((ep)->base_addr + (off))
@@ -185,8 +198,6 @@ struct ep93xx_priv
 #define wrw(ep, off, val)	__raw_writew((val), (ep)->base_addr + (off))
 #define wrl(ep, off, val)	__raw_writel((val), (ep)->base_addr + (off))
 
-static int ep93xx_mdio_read(struct net_device *dev, int phy_id, int reg);
-
 static struct net_device_stats *ep93xx_get_stats(struct net_device *dev)
 {
 	struct ep93xx_priv *ep = netdev_priv(dev);
@@ -542,12 +553,6 @@ static int ep93xx_start_hw(struct net_device *dev)
 		return 1;
 	}
 
-	wrl(ep, REG_SELFCTL, ((ep->mdc_divisor - 1) << 9));
-
-	/* Does the PHY support preamble suppress?  */
-	if ((ep93xx_mdio_read(dev, ep->mii.phy_id, MII_BMSR) & 0x0040) != 0)
-		wrl(ep, REG_SELFCTL, ((ep->mdc_divisor - 1) << 9) | (1 << 8));
-
 	/* Receive descriptor ring.  */
 	addr = ep->descs_dma_addr + offsetof(struct ep93xx_descs, rdesc);
 	wrl(ep, REG_RXDQBADD, addr);
@@ -631,12 +636,11 @@ static int ep93xx_open(struct net_device *dev)
 		return -ENOMEM;
 
 	if (is_zero_ether_addr(dev->dev_addr)) {
+		DECLARE_MAC_BUF(mac_buf);
+
 		random_ether_addr(dev->dev_addr);
-		printk(KERN_INFO "%s: generated random MAC address "
-			"%.2x:%.2x:%.2x:%.2x:%.2x:%.2x.\n", dev->name,
-			dev->dev_addr[0], dev->dev_addr[1],
-			dev->dev_addr[2], dev->dev_addr[3],
-			dev->dev_addr[4], dev->dev_addr[5]);
+		dev_info(&dev->dev, "generated random MAC address %s\n",
+			 print_mac(mac_buf, dev->dev_addr));
 	}
 
 	napi_enable(&ep->napi);
@@ -664,6 +668,8 @@ static int ep93xx_open(struct net_device *dev)
 
 	wrl(ep, REG_GIINTMSK, REG_GIINTMSK_ENABLE);
 
+	phy_start(ep->phy_dev);
+
 	netif_start_queue(dev);
 
 	return 0;
@@ -676,6 +682,9 @@ static int ep93xx_close(struct net_device *dev)
 	napi_disable(&ep->napi);
 	netif_stop_queue(dev);
 
+	if (ep->phy_dev)
+		phy_stop(ep->phy_dev);
+
 	wrl(ep, REG_GIINTMSK, 0);
 	free_irq(ep->irq, dev);
 	ep93xx_stop_hw(dev);
@@ -687,53 +696,103 @@ static int ep93xx_close(struct net_device *dev)
 static int ep93xx_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 {
 	struct ep93xx_priv *ep = netdev_priv(dev);
-	struct mii_ioctl_data *data = if_mii(ifr);
 
-	return generic_mii_ioctl(&ep->mii, data, cmd, NULL);
+	return phy_mii_ioctl(ep->phy_dev, if_mii(ifr), cmd);
 }
 
-static int ep93xx_mdio_read(struct net_device *dev, int phy_id, int reg)
+/* common MII transactions should take < 100 iterations */
+#define EP93XX_PHY_TIMEOUT 2000
+
+static int ep93xx_mdio_wait(struct mii_bus *bus)
 {
-	struct ep93xx_priv *ep = netdev_priv(dev);
-	int data;
-	int i;
+	struct ep93xx_priv *ep = bus->priv;
+	unsigned int timeout = EP93XX_PHY_TIMEOUT;
 
-	wrl(ep, REG_MIICMD, REG_MIICMD_READ | (phy_id << 5) | reg);
+	while ((rdl(ep, REG_MIISTS) & REG_MIISTS_BUSY)
+	      && timeout--)
+		cpu_relax();
 
-	for (i = 0; i < 10; i++) {
-		if ((rdl(ep, REG_MIISTS) & REG_MIISTS_BUSY) == 0)
-			break;
-		msleep(1);
+	if (timeout <= 0) {
+		dev_err(bus->dev, "MII operation timed out\n");
+		return -ETIMEDOUT;
 	}
 
-	if (i == 10) {
-		printk(KERN_INFO DRV_MODULE_NAME ": mdio read timed out\n");
-		data = 0xffff;
-	} else {
-		data = rdl(ep, REG_MIIDATA);
-	}
+	return 0;
+}
+
+
+static int ep93xx_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
+{
+	struct ep93xx_priv *ep = bus->priv;
+	u32 selfctl;
+	u32 data;
+
+	if (ep93xx_mdio_wait(bus) < 0)
+		return -ETIMEDOUT;
+
+	selfctl = rdl(ep, REG_SELFCTL);
+
+	if (ep->phy_supports_mfps)
+	  wrl(ep, REG_SELFCTL, selfctl | REG_SELFCTL_PSPRS);
+	else
+	  wrl(ep, REG_SELFCTL, selfctl & ~REG_SELFCTL_PSPRS);
+
+	wrl(ep, REG_MIICMD, REG_MIICMD_READ | (mii_id << 5) | regnum);
+
+	if (ep93xx_mdio_wait(bus) < 0)
+		return -ETIMEDOUT;
+
+	data =  rdl(ep, REG_MIIDATA);
+
+	wrl(ep, REG_SELFCTL, selfctl);
 
 	return data;
 }
 
-static void ep93xx_mdio_write(struct net_device *dev, int phy_id, int reg, int data)
+static int ep93xx_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
+			     u16 value)
 {
-	struct ep93xx_priv *ep = netdev_priv(dev);
-	int i;
+	struct ep93xx_priv *ep = bus->priv;
+	u32 selfctl;
 
-	wrl(ep, REG_MIIDATA, data);
-	wrl(ep, REG_MIICMD, REG_MIICMD_WRITE | (phy_id << 5) | reg);
+	if (ep93xx_mdio_wait(bus) < 0)
+		return -ETIMEDOUT;
 
-	for (i = 0; i < 10; i++) {
-		if ((rdl(ep, REG_MIISTS) & REG_MIISTS_BUSY) == 0)
-			break;
-		msleep(1);
-	}
+	selfctl = rdl(ep, REG_SELFCTL);
 
-	if (i == 10)
-		printk(KERN_INFO DRV_MODULE_NAME ": mdio write timed out\n");
+	if (ep->phy_supports_mfps)
+	  wrl(ep, REG_SELFCTL, selfctl | REG_SELFCTL_PSPRS);
+	else
+	  wrl(ep, REG_SELFCTL, selfctl & ~REG_SELFCTL_PSPRS);
+
+	wrl(ep, REG_MIIDATA, value);
+	wrl(ep, REG_MIICMD, REG_MIICMD_WRITE | (mii_id << 5) | regnum);
+
+	if (ep93xx_mdio_wait(bus) < 0)
+		return -ETIMEDOUT;
+
+	wrl(ep, REG_SELFCTL, selfctl);
+
+	return 0;
+}
+
+static int ep93xx_mdio_reset(struct mii_bus *bus)
+{
+	struct ep93xx_priv *ep = bus->priv;
+
+	u32 selfctl = rdl(ep, REG_SELFCTL);
+
+	selfctl &= ~(REG_SELFCTL_MDCDIV_MSK | REG_SELFCTL_PSPRS);
+
+	selfctl |= (ep->mdc_divisor - 1) << REG_SELFCTL_MDCDIV_OFS;
+	selfctl |= REG_SELFCTL_PSPRS;
+
+	wrl(ep, REG_SELFCTL, selfctl);
+
+	return 0;
 }
 
+
 static void ep93xx_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
 {
 	strcpy(info->driver, DRV_MODULE_NAME);
@@ -743,33 +802,30 @@ static void ep93xx_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *i
 static int ep93xx_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 {
 	struct ep93xx_priv *ep = netdev_priv(dev);
-	return mii_ethtool_gset(&ep->mii, cmd);
+	struct phy_device *phydev = ep->phy_dev;
+
+	if (!phydev)
+		return -ENODEV;
+
+	return phy_ethtool_gset(phydev, cmd);
 }
 
 static int ep93xx_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 {
 	struct ep93xx_priv *ep = netdev_priv(dev);
-	return mii_ethtool_sset(&ep->mii, cmd);
-}
+	struct phy_device *phydev = ep->phy_dev;
 
-static int ep93xx_nway_reset(struct net_device *dev)
-{
-	struct ep93xx_priv *ep = netdev_priv(dev);
-	return mii_nway_restart(&ep->mii);
-}
+	if (!phydev)
+		return -ENODEV;
 
-static u32 ep93xx_get_link(struct net_device *dev)
-{
-	struct ep93xx_priv *ep = netdev_priv(dev);
-	return mii_link_ok(&ep->mii);
+	return phy_ethtool_sset(phydev, cmd);
 }
 
 static struct ethtool_ops ep93xx_ethtool_ops = {
 	.get_drvinfo		= ep93xx_get_drvinfo,
 	.get_settings		= ep93xx_get_settings,
 	.set_settings		= ep93xx_set_settings,
-	.nway_reset		= ep93xx_nway_reset,
-	.get_link		= ep93xx_get_link,
+	.get_link		= ethtool_op_get_link,
 };
 
 struct net_device *ep93xx_dev_alloc(struct ep93xx_eth_data *data)
@@ -824,15 +880,127 @@ static int ep93xx_eth_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static void ep93xx_adjust_link(struct net_device *dev)
+{
+	struct ep93xx_priv *ep = netdev_priv(dev);
+	struct phy_device *phydev = ep->phy_dev;
+
+	int status_change = 0;
+
+	if (phydev->link) {
+		if ((ep->speed != phydev->speed) ||
+		    (ep->duplex != phydev->duplex)) {
+			/* speed and/or duplex state changed */
+			u32 testctl = rdl(ep, REG_TESTCTL);
+
+			if (DUPLEX_FULL == phydev->duplex)
+				testctl |= REG_TESTCTL_MFDX;
+			else
+				testctl &= ~(REG_TESTCTL_MFDX);
+
+			wrl(ep, REG_TESTCTL, testctl);
+
+			ep->speed = phydev->speed;
+			ep->duplex = phydev->duplex;
+			status_change = 1;
+		}
+	}
+
+	/* test for online/offline link transition */
+	if (phydev->link != ep->link) {
+		if (phydev->link) /* link went online */
+			netif_schedule(dev);
+		else { /* link went offline */
+			ep->speed = 0;
+			ep->duplex = -1;
+		}
+		ep->link = phydev->link;
+
+		status_change = 1;
+	}
+
+	if (status_change)
+		phy_print_status(phydev);
+}
+
+static int ep93xx_mii_probe(struct net_device *dev, int phy_addr)
+{
+	struct ep93xx_priv *ep = netdev_priv(dev);
+	struct phy_device *phydev = NULL;
+	int val;
+
+	if (phy_addr >= 0 && phy_addr < PHY_MAX_ADDR)
+		phydev = ep->mii_bus.phy_map[phy_addr];
+
+	if (!phydev) {
+		dev_info(&dev->dev,
+			 "PHY not found at specified address,"
+			 " trying autodetection\n");
+
+		/* find the first phy */
+		for (phy_addr = 0; phy_addr < PHY_MAX_ADDR; phy_addr++) {
+			if (ep->mii_bus.phy_map[phy_addr]) {
+				phydev = ep->mii_bus.phy_map[phy_addr];
+				break;
+			}
+		}
+	}
+
+	if (!phydev) {
+		dev_err(&dev->dev, "no PHY found\n");
+		return -ENODEV;
+	}
+
+	phydev = phy_connect(dev, phydev->dev.bus_id,
+			     ep93xx_adjust_link, 0, PHY_INTERFACE_MODE_MII);
+
+	if (IS_ERR(phydev)) {
+		dev_err(&dev->dev, "Could not attach to PHY\n");
+		return PTR_ERR(phydev);
+	}
+
+	ep->phy_supports_mfps = 0;
+
+	val = phy_read(phydev, MII_BMSR);
+	if (val < 0) {
+		dev_err(&phydev->dev, "failed to read MII register\n");
+		return val;
+	}
+
+	if (val & 0x0040) {
+		dev_info(&phydev->dev,
+			 "PHY supports MII frame preamble suppression\n");
+		ep->phy_supports_mfps = 1;
+	}
+
+	phydev->supported &= PHY_BASIC_FEATURES;
+
+	phydev->advertising = phydev->supported;
+
+	ep->link = 0;
+	ep->speed = 0;
+	ep->duplex = -1;
+	ep->phy_dev = phydev;
+
+	dev_info(&dev->dev, "attached PHY driver [%s] "
+		 "(mii_bus:phy_addr=%s, irq=%d)\n",
+		 phydev->drv->name, phydev->dev.bus_id, phydev->irq);
+
+	return 0;
+}
+
+
 static int ep93xx_eth_probe(struct platform_device *pdev)
 {
 	struct ep93xx_eth_data *data;
 	struct net_device *dev;
 	struct ep93xx_priv *ep;
-	int err;
+	DECLARE_MAC_BUF(mac_buf);
+	int err, i;
 
 	if (pdev == NULL)
 		return -ENODEV;
+
 	data = pdev->dev.platform_data;
 
 	dev = ep93xx_dev_alloc(data);
@@ -852,7 +1020,7 @@ static int ep93xx_eth_probe(struct platform_device *pdev)
 	if (ep->res == NULL) {
 		dev_err(&pdev->dev, "Could not reserve memory region\n");
 		err = -ENOMEM;
-		goto err_out;
+		goto err_out_request_mem_region;
 	}
 
 	ep->base_addr = ioremap(pdev->resource[0].start,
@@ -860,34 +1028,74 @@ static int ep93xx_eth_probe(struct platform_device *pdev)
 	if (ep->base_addr == NULL) {
 		dev_err(&pdev->dev, "Failed to ioremap ethernet registers\n");
 		err = -EIO;
-		goto err_out;
+		goto err_out_ioremap;
 	}
 	ep->irq = pdev->resource[1].start;
 
-	ep->mii.phy_id = data->phy_id;
-	ep->mii.phy_id_mask = 0x1f;
-	ep->mii.reg_num_mask = 0x1f;
-	ep->mii.dev = dev;
-	ep->mii.mdio_read = ep93xx_mdio_read;
-	ep->mii.mdio_write = ep93xx_mdio_write;
+	/* mdio/mii bus */
+	ep->mii_bus.name = "ep93xx_mii_bus";
+	ep->mii_bus.id = 0;
+
+	ep->mii_bus.read = ep93xx_mdio_read;
+	ep->mii_bus.write = ep93xx_mdio_write;
+	ep->mii_bus.reset = ep93xx_mdio_reset;
+
+	ep->mii_bus.phy_mask = 0;
+
+	ep->mii_bus.priv = ep;
+	ep->mii_bus.dev = &dev->dev;
+
+	ep->mii_bus.irq = kmalloc(sizeof(int)*PHY_MAX_ADDR, GFP_KERNEL);
+	if (NULL == ep->mii_bus.irq) {
+		dev_err(&pdev->dev, "Could not allocate memory\n");
+		err = -ENOMEM;
+		goto err_out_mii_bus_irq_kmalloc;
+	}
+
+	for (i = 0; i < PHY_MAX_ADDR; i++)
+		ep->mii_bus.irq[i] = PHY_POLL;
+
 	ep->mdc_divisor = 40;	/* Max HCLK 100 MHz, min MDIO clk 2.5 MHz.  */
+	ep->phy_supports_mfps = 0; /* probe without preamble suppression */
 
 	err = register_netdev(dev);
 	if (err) {
 		dev_err(&pdev->dev, "Failed to register netdev\n");
-		goto err_out;
+		goto err_out_register_netdev;
 	}
 
-	printk(KERN_INFO "%s: ep93xx on-chip ethernet, IRQ %d, "
-			 "%.2x:%.2x:%.2x:%.2x:%.2x:%.2x.\n", dev->name,
-			ep->irq, data->dev_addr[0], data->dev_addr[1],
-			data->dev_addr[2], data->dev_addr[3],
-			data->dev_addr[4], data->dev_addr[5]);
+	err = mdiobus_register(&ep->mii_bus);
+	if (err) {
+		dev_err(&dev->dev, "Could not register MII bus\n");
+		goto err_out_mdiobus_register;
+	}
+
+	err = ep93xx_mii_probe(dev, data->phy_id);
+	if (err) {
+		dev_err(&dev->dev, "failed to probe MII bus\n");
+		goto err_out_mii_probe;
+	}
+
+	dev_info(&dev->dev, "ep93xx on-chip ethernet, IRQ %d, %s\n",
+		 ep->irq, print_mac(mac_buf, dev->dev_addr));
 
 	return 0;
 
+err_out_mii_probe:
+	mdiobus_unregister(&ep->mii_bus);
+err_out_mdiobus_register:
+	unregister_netdev(dev);
+err_out_register_netdev:
+	kfree(ep->mii_bus.irq);
+err_out_mii_bus_irq_kmalloc:
+	iounmap(ep->base_addr);
+err_out_ioremap:
+	release_resource(ep->res);
+	kfree(ep->res);
+err_out_request_mem_region:
+	free_netdev(dev);
 err_out:
-	ep93xx_eth_remove(pdev);
+
 	return err;
 }
 
-- 
1.5.3.4