net: macb: Added ZynqMP-specific initialization

The GEM controllers on ZynqMP were missing some initialization steps which
are required in some cases when using SGMII mode, which uses the PS-GTR
transceivers managed by the phy-zynqmp driver.

The GEM core appears to need a hardware-level reset in order to work
properly in SGMII mode in cases where the GT reference clock was not
present at initial power-on. This can be done using a reset mapped to
the zynqmp-reset driver in the device tree.

Also, when in SGMII mode, the GEM driver needs to ensure the PHY is
initialized and powered on.

Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
index 9ddbee7de72b9f275d673cb95df2df6cf3dd9b3b..f0a7d8396a4aee1514a577866518e214dceab231 100644 (file)
--- a/drivers/net/ethernet/cadence/macb.h
+++ b/drivers/net/ethernet/cadence/macb.h
@@ -12,6 +12,7 @@
 #include <linux/ptp_clock_kernel.h>
 #include <linux/net_tstamp.h>
 #include <linux/interrupt.h>
+#include <linux/phy/phy.h>
 
 #if defined(CONFIG_ARCH_DMA_ADDR_T_64BIT) || defined(CONFIG_MACB_USE_HWSTAMP)
 #define MACB_EXT_DESC
@@ -1291,6 +1292,9 @@ struct macb {
        u32                     wol;
 
        struct macb_ptp_info    *ptp_info;      /* macb-ptp interface */
+
+       struct phy              *sgmii_phy;     /* for ZynqMP SGMII mode */
+
 #ifdef MACB_EXT_DESC
        uint8_t hw_dma_cap;
 #endif

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index a363da928e8b37dbfc134d6b96d4cf521dc0f008..1ce20bf52f727d21d870a69de9d0e8559cfcbf94 100644 (file)
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -34,7 +34,9 @@
 #include <linux/udp.h>
 #include <linux/tcp.h>
 #include <linux/iopoll.h>
+#include <linux/phy/phy.h>
 #include <linux/pm_runtime.h>
+#include <linux/reset.h>
 #include "macb.h"
 
 /* This structure is only used for MACB on SiFive FU540 devices */
@@ -2739,10 +2741,14 @@ static int macb_open(struct net_device *dev)
 
        macb_init_hw(bp);
 
-       err = macb_phylink_connect(bp);
+       err = phy_power_on(bp->sgmii_phy);
        if (err)
                goto reset_hw;
 
+       err = macb_phylink_connect(bp);
+       if (err)
+               goto phy_off;
+
        netif_tx_start_all_queues(dev);
 
        if (bp->ptp_info)
@@ -2750,6 +2756,9 @@ static int macb_open(struct net_device *dev)
 
        return 0;
 
+phy_off:
+       phy_power_off(bp->sgmii_phy);
+
 reset_hw:
        macb_reset_hw(bp);
        for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue)
@@ -2775,6 +2784,8 @@ static int macb_close(struct net_device *dev)
        phylink_stop(bp->phylink);
        phylink_disconnect_phy(bp->phylink);
 
+       phy_power_off(bp->sgmii_phy);
+
        spin_lock_irqsave(&bp->lock, flags);
        macb_reset_hw(bp);
        netif_carrier_off(dev);
@@ -4544,13 +4555,55 @@ static const struct macb_config np4_config = {
        .usrio = &macb_default_usrio,
 };
 
+static int zynqmp_init(struct platform_device *pdev)
+{
+       struct net_device *dev = platform_get_drvdata(pdev);
+       struct macb *bp = netdev_priv(dev);
+       int ret;
+
+       if (bp->phy_interface == PHY_INTERFACE_MODE_SGMII) {
+               /* Ensure PS-GTR PHY device used in SGMII mode is ready */
+               bp->sgmii_phy = devm_phy_get(&pdev->dev, "sgmii-phy");
+
+               if (IS_ERR(bp->sgmii_phy)) {
+                       ret = PTR_ERR(bp->sgmii_phy);
+                       dev_err_probe(&pdev->dev, ret,
+                                     "failed to get PS-GTR PHY\n");
+                       return ret;
+               }
+
+               ret = phy_init(bp->sgmii_phy);
+               if (ret) {
+                       dev_err(&pdev->dev, "failed to init PS-GTR PHY: %d\n",
+                               ret);
+                       return ret;
+               }
+       }
+
+       /* Fully reset GEM controller at hardware level using zynqmp-reset driver,
+        * if mapped in device tree.
+        */
+       ret = device_reset_optional(&pdev->dev);
+       if (ret) {
+               dev_err_probe(&pdev->dev, ret, "failed to reset controller");
+               phy_exit(bp->sgmii_phy);
+               return ret;
+       }
+
+       ret = macb_init(pdev);
+       if (ret)
+               phy_exit(bp->sgmii_phy);
+
+       return ret;
+}
+
 static const struct macb_config zynqmp_config = {
        .caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE |
                        MACB_CAPS_JUMBO |
                        MACB_CAPS_GEM_HAS_PTP | MACB_CAPS_BD_RD_PREFETCH,
        .dma_burst_length = 16,
        .clk_init = macb_clk_init,
-       .init = macb_init,
+       .init = zynqmp_init,
        .jumbo_max_len = 10240,
        .usrio = &macb_default_usrio,
 };
@@ -4767,7 +4820,7 @@ static int macb_probe(struct platform_device *pdev)
 
        err = macb_mii_init(bp);
        if (err)
-               goto err_out_free_netdev;
+               goto err_out_phy_exit;
 
        netif_carrier_off(dev);
 
@@ -4792,6 +4845,9 @@ err_out_unregister_mdio:
        mdiobus_unregister(bp->mii_bus);
        mdiobus_free(bp->mii_bus);
 
+err_out_phy_exit:
+       phy_exit(bp->sgmii_phy);
+
 err_out_free_netdev:
        free_netdev(dev);
 
@@ -4813,6 +4869,7 @@ static int macb_remove(struct platform_device *pdev)
 
        if (dev) {
                bp = netdev_priv(dev);
+               phy_exit(bp->sgmii_phy);
                mdiobus_unregister(bp->mii_bus);
                mdiobus_free(bp->mii_bus);