zynq-7000系列基于zynq-zed的MAC->MAC 的实现（fixed-link）

zynq-7000系列基于zynq-zed的MAC->MAC 的实现（fixed-link）

                             作者：卢浩  

                                     时间：2017.2.20

                                    转载请注明出处

                                                                

前言：在项目实际使用中，我们有一些应用可以省去以太网phy芯片的，这里我就拿zynq-zed开发板做评估测试。

在VIVADO工程中去掉以太网的MDIO MDC配置，这样就无法读取PHY状态了，因为mac->mac这种连接就是无phy模式下的通讯。

修改内核drivers/net/ethernet/cadence/macb.c文件

@@ -383,27 +383,37 @@ static int macb_mii_probe(struct net_device *dev

 int phy_irq; int ret; -phydev = phy_find_first(bp->mii_bus);-if (!phydev) {-netdev_err(dev, "no PHY found\n");-return -ENXIO;-}+if (bp->phy_node) {+phydev = of_phy_connect(dev, bp->phy_node,+&macb_handle_link_change, 0,+bp->phy_interface);+if (!phydev)+return -ENODEV;+} else {+phydev = phy_find_first(bp->mii_bus);+if (!phydev) {+netdev_err(dev, "no PHY found\n");+return -ENXIO;+} -pdata = dev_get_platdata(&bp->pdev->dev);-if (pdata && gpio_is_valid(pdata->phy_irq_pin)) {-ret = devm_gpio_request(&bp->pdev->dev, pdata->phy_irq_pin, "phy int");-if (!ret) {-phy_irq = gpio_to_irq(pdata->phy_irq_pin);-phydev->irq = (phy_irq < 0) ? PHY_POLL : phy_irq;+pdata = dev_get_platdata(&bp->pdev->dev);+if (pdata && gpio_is_valid(pdata->phy_irq_pin)) {+ret = devm_gpio_request(&bp->pdev->dev,+pdata->phy_irq_pin, "phy int");+if (!ret) {+phy_irq = gpio_to_irq(pdata->phy_irq_pin);+phydev->irq = (phy_irq < 0) ?+      PHY_POLL : phy_irq;+} }-} -/* attach the mac to the phy */-ret = phy_connect_direct(dev, phydev, &macb_handle_link_change,- bp->phy_interface);-if (ret) {-netdev_err(dev, "Could not attach to PHY\n");-return ret;+/* attach the mac to the phy */+ret = phy_connect_direct(dev, phydev, &macb_handle_link_change,+ bp->phy_interface);+if (ret) {+netdev_err(dev, "Could not attach to PHY\n");+return ret;+} }  /* mask with MAC supported features */ @@ -3461,14 +3471,21 @@ static int macb_probe(struct platform_device *pdev) macb_get_hwaddr(bp);  /* Power up the PHY if there is a GPIO reset */-phy_node =  of_get_next_available_child(np, NULL);-if (phy_node) {+phy_node = of_parse_phandle(np, "phy-handle", 0);+if (!phy_node && of_phy_is_fixed_link(np)) {+err = of_phy_register_fixed_link(np);+if (err < 0) {+dev_err(&pdev->dev, "broken fixed-link specification");+goto failed_phy;+}+phy_node = of_node_get(np);+bp->phy_node = phy_node;+} else { int gpio = of_get_named_gpio(phy_node, "reset-gpios", 0); if (gpio_is_valid(gpio)) bp->reset_gpio = gpio_to_desc(gpio); gpiod_set_value(bp->reset_gpio, GPIOD_OUT_HIGH); }-of_node_put(phy_node);  err = of_get_phy_mode(np); if (err < 0) { @@ -3518,6 +3535,9 @@ static int macb_probe(struct platform_device *pdev) err_out_free_netdev: free_netdev(dev); +failed_phy:+of_node_put(phy_node);+ err_disable_clocks: clk_disable_unprepare(tx_clk); clk_disable_unprepare(hclk); @@ -3547,6 +3567,7 @@ static int macb_remove(struct platform_device *pdev) clk_disable_unprepare(bp->tx_clk); clk_disable_unprepare(bp->hclk); clk_disable_unprepare(bp->pclk);+of_node_put(bp->phy_node); free_netdev(dev); } 

修改内核drivers/net/ethernet/cadence/macb.h文件

@@ -906,6 +906,7 @@ struct macb {

 struct mii_bus*mii_bus; struct phy_device*phy_dev;+struct device_node*phy_node; int link; int speed; int duplex;

在内核配置文件中添加如下配置：

CONFIG_ETHERNET
CONFIG_NET_CADENCE
CONFIG_MACB
CONFIG_NETDEVICES
CONFIG_HAS_DMA

在dts文件增加如下修改：

修改前：

 51 &gem0 {
 52         status = "okay";
 53         phy-mode = "rgmii-id";
 54         phy-handle = <&ethernet_phy>;
 55 
 56         ethernet_phy: ethernet-phy@0 {
 57                 reg = <0>;
 58         };
 59 };

修改后：

 55 &gem0 {
 56                   status = "okay";
 57                   phy-mode = "rgmii-id";
 58                   fixed-link {
 59                                speed = <1000>;
 60                                full-duplex;
 61                              };
 68   };

重新编译内核和dts文件。

上电启动zynq-zed开发板，对网卡进行测试，此时网卡被强制到1000M FULL模式。PHYADDR是0-31.