4 files changed, 153 insertions, 7 deletions

diff --git a/drivers/net/ethernet/qualcomm/emac/emac-mac.c b/drivers/net/ethernet/qualcomm/emac/emac-mac.c
index 33d7ff1f40e0..b991219862b1 100644
--- a/drivers/net/ethernet/qualcomm/emac/emac-mac.c
+++ b/drivers/net/ethernet/qualcomm/emac/emac-mac.c
@@ -951,12 +951,16 @@ static void emac_mac_rx_descs_refill(struct emac_adapter *adpt,
 static void emac_adjust_link(struct net_device *netdev)
 {
         struct emac_adapter *adpt = netdev_priv(netdev);
+        struct emac_sgmii *sgmii = &adpt->phy;
         struct phy_device *phydev = netdev->phydev;
 
-        if (phydev->link)
+        if (phydev->link) {
                 emac_mac_start(adpt);
-        else
+                sgmii->link_up(adpt);
+        } else {
+                sgmii->link_down(adpt);
                 emac_mac_stop(adpt);
+        }
 
         phy_print_status(phydev);
 }
diff --git a/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c b/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c
index b5269c4dd4ee..040b28977ee7 100644
--- a/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c
+++ b/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c
@@ -25,7 +25,9 @@
 #define EMAC_SGMII_PHY_SPEED_CFG1               0x0074
 #define EMAC_SGMII_PHY_IRQ_CMD                  0x00ac
 #define EMAC_SGMII_PHY_INTERRUPT_CLEAR          0x00b0
+#define EMAC_SGMII_PHY_INTERRUPT_MASK           0x00b4
 #define EMAC_SGMII_PHY_INTERRUPT_STATUS         0x00b8
+#define EMAC_SGMII_PHY_RX_CHK_STATUS            0x00d4
 
 #define FORCE_AN_TX_CFG                         BIT(5)
 #define FORCE_AN_RX_CFG                         BIT(4)
@@ -36,6 +38,8 @@
 #define SPDMODE_100                             BIT(0)
 #define SPDMODE_10                              0
 
+#define CDR_ALIGN_DET                           BIT(6)
+
 #define IRQ_GLOBAL_CLEAR                        BIT(0)
 
 #define DECODE_CODE_ERR                         BIT(7)
@@ -44,6 +48,7 @@
 #define SGMII_PHY_IRQ_CLR_WAIT_TIME             10
 
 #define SGMII_PHY_INTERRUPT_ERR         (DECODE_CODE_ERR | DECODE_DISP_ERR)
+#define SGMII_ISR_MASK                  (SGMII_PHY_INTERRUPT_ERR)
 
 #define SERDES_START_WAIT_TIMES                 100
 
@@ -96,6 +101,51 @@ static int emac_sgmii_irq_clear(struct emac_adapter *adpt, u32 irq_bits)
         return 0;
 }
 
+/* The number of decode errors that triggers a reset */
+#define DECODE_ERROR_LIMIT      2
+
+static irqreturn_t emac_sgmii_interrupt(int irq, void *data)
+{
+        struct emac_adapter *adpt = data;
+        struct emac_sgmii *phy = &adpt->phy;
+        u32 status;
+
+        status = readl(phy->base + EMAC_SGMII_PHY_INTERRUPT_STATUS);
+        status &= SGMII_ISR_MASK;
+        if (!status)
+                return IRQ_HANDLED;
+
+        /* If we get a decoding error and CDR is not locked, then try
+         * resetting the internal PHY.  The internal PHY uses an embedded
+         * clock with Clock and Data Recovery (CDR) to recover the
+         * clock and data.
+         */
+        if (status & SGMII_PHY_INTERRUPT_ERR) {
+                int count;
+
+                /* The SGMII is capable of recovering from some decode
+                 * errors automatically.  However, if we get multiple
+                 * decode errors in a row, then assume that something
+                 * is wrong and reset the interface.
+                 */
+                count = atomic_inc_return(&phy->decode_error_count);
+                if (count == DECODE_ERROR_LIMIT) {
+                        schedule_work(&adpt->work_thread);
+                        atomic_set(&phy->decode_error_count, 0);
+                }
+        } else {
+                /* We only care about consecutive decode errors. */
+                atomic_set(&phy->decode_error_count, 0);
+        }
+
+        if (emac_sgmii_irq_clear(adpt, status)) {
+                netdev_warn(adpt->netdev, "failed to clear SGMII interrupt\n");
+                schedule_work(&adpt->work_thread);
+        }
+
+        return IRQ_HANDLED;
+}
+
 static void emac_sgmii_reset_prepare(struct emac_adapter *adpt)
 {
         struct emac_sgmii *phy = &adpt->phy;
@@ -129,6 +179,68 @@ void emac_sgmii_reset(struct emac_adapter *adpt)
                            ret);
 }
 
+static int emac_sgmii_open(struct emac_adapter *adpt)
+{
+        struct emac_sgmii *sgmii = &adpt->phy;
+        int ret;
+
+        if (sgmii->irq) {
+                /* Make sure interrupts are cleared and disabled first */
+                ret = emac_sgmii_irq_clear(adpt, 0xff);
+                if (ret)
+                        return ret;
+                writel(0, sgmii->base + EMAC_SGMII_PHY_INTERRUPT_MASK);
+
+                ret = request_irq(sgmii->irq, emac_sgmii_interrupt, 0,
+                                  "emac-sgmii", adpt);
+                if (ret) {
+                        netdev_err(adpt->netdev,
+                                   "could not register handler for internal PHY\n");
+                        return ret;
+                }
+        }
+
+        return 0;
+}
+
+static int emac_sgmii_close(struct emac_adapter *adpt)
+{
+        struct emac_sgmii *sgmii = &adpt->phy;
+
+        /* Make sure interrupts are disabled */
+        writel(0, sgmii->base + EMAC_SGMII_PHY_INTERRUPT_MASK);
+        free_irq(sgmii->irq, adpt);
+
+        return 0;
+}
+
+/* The error interrupts are only valid after the link is up */
+static int emac_sgmii_link_up(struct emac_adapter *adpt)
+{
+        struct emac_sgmii *sgmii = &adpt->phy;
+        int ret;
+
+        /* Clear and enable interrupts */
+        ret = emac_sgmii_irq_clear(adpt, 0xff);
+        if (ret)
+                return ret;
+
+        writel(SGMII_ISR_MASK, sgmii->base + EMAC_SGMII_PHY_INTERRUPT_MASK);
+
+        return 0;
+}
+
+static int emac_sgmii_link_down(struct emac_adapter *adpt)
+{
+        struct emac_sgmii *sgmii = &adpt->phy;
+
+        /* Disable interrupts */
+        writel(0, sgmii->base + EMAC_SGMII_PHY_INTERRUPT_MASK);
+        synchronize_irq(sgmii->irq);
+
+        return 0;
+}
+
 static int emac_sgmii_acpi_match(struct device *dev, void *data)
 {
 #ifdef CONFIG_ACPI
@@ -139,7 +251,7 @@ static int emac_sgmii_acpi_match(struct device *dev, void *data)
                 {}
         };
         const struct acpi_device_id *id = acpi_match_device(match_table, dev);
-        emac_sgmii_initialize *initialize = data;
+        emac_sgmii_function *initialize = data;
 
         if (id) {
                 acpi_handle handle = ACPI_HANDLE(dev);
@@ -226,9 +338,14 @@ int emac_sgmii_config(struct platform_device *pdev, struct emac_adapter *adpt)
                         goto error_put_device;
                 }
 
-                phy->initialize = (emac_sgmii_initialize)match->data;
+                phy->initialize = (emac_sgmii_function)match->data;
         }
 
+        phy->open = emac_sgmii_open;
+        phy->close = emac_sgmii_close;
+        phy->link_up = emac_sgmii_link_up;
+        phy->link_down = emac_sgmii_link_down;
+
         /* Base address is the first address */
         res = platform_get_resource(sgmii_pdev, IORESOURCE_MEM, 0);
         if (!res) {
@@ -256,9 +373,12 @@ int emac_sgmii_config(struct platform_device *pdev, struct emac_adapter *adpt)
         if (ret)
                 goto error;
 
-        emac_sgmii_irq_clear(adpt, SGMII_PHY_INTERRUPT_ERR);
         emac_sgmii_link_init(adpt);
 
+        ret = platform_get_irq(sgmii_pdev, 0);
+        if (ret > 0)
+                phy->irq = ret;
+
         /* We've remapped the addresses, so we don't need the device any
          * more.  of_find_device_by_node() says we should release it.
          */
diff --git a/drivers/net/ethernet/qualcomm/emac/emac-sgmii.h b/drivers/net/ethernet/qualcomm/emac/emac-sgmii.h
index 4a8f6b174f4b..e7c0c3b2baa4 100644
--- a/drivers/net/ethernet/qualcomm/emac/emac-sgmii.h
+++ b/drivers/net/ethernet/qualcomm/emac/emac-sgmii.h
@@ -16,17 +16,29 @@
 struct emac_adapter;
 struct platform_device;
 
-typedef int (*emac_sgmii_initialize)(struct emac_adapter *adpt);
+typedef int (*emac_sgmii_function)(struct emac_adapter *adpt);
 
 /** emac_sgmii - internal emac phy
  * @base base address
  * @digital per-lane digital block
+ * @irq the interrupt number
+ * @decode_error_count reference count of consecutive decode errors
  * @initialize initialization function
+ * @open called when the driver is opened
+ * @close called when the driver is closed
+ * @link_up called when the link comes up
+ * @link_down called when the link comes down
  */
 struct emac_sgmii {
         void __iomem            *base;
         void __iomem            *digital;
-        emac_sgmii_initialize   initialize;
+        unsigned int            irq;
+        atomic_t                decode_error_count;
+        emac_sgmii_function     initialize;
+        emac_sgmii_function     open;
+        emac_sgmii_function     close;
+        emac_sgmii_function     link_up;
+        emac_sgmii_function     link_down;
 };
 
 int emac_sgmii_config(struct platform_device *pdev, struct emac_adapter *adpt);
diff --git a/drivers/net/ethernet/qualcomm/emac/emac.c b/drivers/net/ethernet/qualcomm/emac/emac.c
index 75305ad436d5..f519351ef3a2 100644
--- a/drivers/net/ethernet/qualcomm/emac/emac.c
+++ b/drivers/net/ethernet/qualcomm/emac/emac.c
@@ -280,6 +280,14 @@ static int emac_open(struct net_device *netdev)
                 return ret;
         }
 
+        ret = adpt->phy.open(adpt);
+        if (ret) {
+                emac_mac_down(adpt);
+                emac_mac_rx_tx_rings_free_all(adpt);
+                free_irq(irq->irq, irq);
+                return ret;
+        }
+
         return 0;
 }
 
@@ -290,6 +298,7 @@ static int emac_close(struct net_device *netdev)
 
         mutex_lock(&adpt->reset_lock);
 
+        adpt->phy.close(adpt);
         emac_mac_down(adpt);
         emac_mac_rx_tx_rings_free_all(adpt);
 
@@ -645,6 +654,7 @@ static int emac_probe(struct platform_device *pdev)
         adpt->msg_enable = EMAC_MSG_DEFAULT;
 
         phy = &adpt->phy;
+        atomic_set(&phy->decode_error_count, 0);
 
         mutex_init(&adpt->reset_lock);
         spin_lock_init(&adpt->stats.lock);