net: ftgmac100: Ungate RCLK for RMII on ASPEED MACs

The 50MHz RCLK has to be enabled before the RMII interface will function.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c
index 9b7af94..8243102 100644 (file)
--- a/drivers/net/ethernet/faraday/ftgmac100.c
+++ b/drivers/net/ethernet/faraday/ftgmac100.c
@@ -90,6 +90,9 @@ struct ftgmac100 {
        struct mii_bus *mii_bus;
        struct clk *clk;
 
+       /* AST2500/AST2600 RMII ref clock gate */
+       struct clk *rclk;
+
        /* Link management */
        int cur_speed;
        int cur_duplex;
@@ -1718,20 +1721,41 @@ static void ftgmac100_ncsi_handler(struct ncsi_dev *nd)
                   nd->link_up ? "up" : "down");
 }
 
-static void ftgmac100_setup_clk(struct ftgmac100 *priv)
+static int ftgmac100_setup_clk(struct ftgmac100 *priv)
 {
-       priv->clk = devm_clk_get(priv->dev, NULL);
-       if (IS_ERR(priv->clk))
-               return;
+       struct clk *clk;
+       int rc;
 
-       clk_prepare_enable(priv->clk);
+       clk = devm_clk_get(priv->dev, NULL /* MACCLK */);
+       if (IS_ERR(clk))
+               return PTR_ERR(clk);
+       priv->clk = clk;
+       rc = clk_prepare_enable(priv->clk);
+       if (rc)
+               return rc;
 
        /* Aspeed specifies a 100MHz clock is required for up to
         * 1000Mbit link speeds. As NCSI is limited to 100Mbit, 25MHz
         * is sufficient
         */
-       clk_set_rate(priv->clk, priv->use_ncsi ? FTGMAC_25MHZ :
-                       FTGMAC_100MHZ);
+       rc = clk_set_rate(priv->clk, priv->use_ncsi ? FTGMAC_25MHZ :
+                         FTGMAC_100MHZ);
+       if (rc)
+               goto cleanup_clk;
+
+       /* RCLK is for RMII, typically used for NCSI. Optional because its not
+        * necessary if it's the AST2400 MAC, or the MAC is configured for
+        * RGMII, or the controller is not an ASPEED-based controller.
+        */
+       priv->rclk = devm_clk_get_optional(priv->dev, "RCLK");
+       rc = clk_prepare_enable(priv->rclk);
+       if (!rc)
+               return 0;
+
+cleanup_clk:
+       clk_disable_unprepare(priv->clk);
+
+       return rc;
 }
 
 static int ftgmac100_probe(struct platform_device *pdev)
@@ -1853,8 +1877,11 @@ static int ftgmac100_probe(struct platform_device *pdev)
                        goto err_setup_mdio;
        }
 
-       if (priv->is_aspeed)
-               ftgmac100_setup_clk(priv);
+       if (priv->is_aspeed) {
+               err = ftgmac100_setup_clk(priv);
+               if (err)
+                       goto err_ncsi_dev;
+       }
 
        /* Default ring sizes */
        priv->rx_q_entries = priv->new_rx_q_entries = DEF_RX_QUEUE_ENTRIES;
@@ -1886,8 +1913,10 @@ static int ftgmac100_probe(struct platform_device *pdev)
 
        return 0;
 
-err_ncsi_dev:
 err_register_netdev:
+       clk_disable_unprepare(priv->rclk);
+       clk_disable_unprepare(priv->clk);
+err_ncsi_dev:
        ftgmac100_destroy_mdio(netdev);
 err_setup_mdio:
        iounmap(priv->base);
@@ -1909,6 +1938,7 @@ static int ftgmac100_remove(struct platform_device *pdev)
 
        unregister_netdev(netdev);
 
+       clk_disable_unprepare(priv->rclk);
        clk_disable_unprepare(priv->clk);
 
        /* There's a small chance the reset task will have been re-queued,