net: phy: marvell-88q2xxx: add interrupt support for link detection

Added .config_intr and .handle_interrupt callbacks. Whenever the link
goes up or down an interrupt will be triggered. Interrupts are configured
separately for 100/1000BASET1.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Dimitri Fedrau <dima.fedrau@gmail.com>
Link: https://lore.kernel.org/r/20240218075753.18067-7-dima.fedrau@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/phy/marvell-88q2xxx.c b/drivers/net/phy/marvell-88q2xxx.c
index 9829facde253374c6d2ad83c926e2117f20faee8..7c7517af346bd7450906cefd78c21a531c71c045 100644 (file)
--- a/drivers/net/phy/marvell-88q2xxx.c
+++ b/drivers/net/phy/marvell-88q2xxx.c
@@ -24,6 +24,19 @@
 #define MDIO_MMD_AN_MV_STAT2_100BT1            0x2000
 #define MDIO_MMD_AN_MV_STAT2_1000BT1           0x4000
 
+#define MDIO_MMD_PCS_MV_INT_EN                 32784
+#define MDIO_MMD_PCS_MV_INT_EN_LINK_UP         0x0040
+#define MDIO_MMD_PCS_MV_INT_EN_LINK_DOWN       0x0080
+#define MDIO_MMD_PCS_MV_INT_EN_100BT1          0x1000
+
+#define MDIO_MMD_PCS_MV_GPIO_INT_STAT                  32785
+#define MDIO_MMD_PCS_MV_GPIO_INT_STAT_LINK_UP          0x0040
+#define MDIO_MMD_PCS_MV_GPIO_INT_STAT_LINK_DOWN                0x0080
+#define MDIO_MMD_PCS_MV_GPIO_INT_STAT_100BT1_GEN       0x1000
+
+#define MDIO_MMD_PCS_MV_GPIO_INT_CTRL                  32787
+#define MDIO_MMD_PCS_MV_GPIO_INT_CTRL_TRI_DIS          0x0800
+
 #define MDIO_MMD_PCS_MV_100BT1_STAT1                   33032
 #define MDIO_MMD_PCS_MV_100BT1_STAT1_IDLE_ERROR                0x00ff
 #define MDIO_MMD_PCS_MV_100BT1_STAT1_JABBER            0x0100
@@ -38,6 +51,12 @@
 #define MDIO_MMD_PCS_MV_100BT1_STAT2_LINK      0x0004
 #define MDIO_MMD_PCS_MV_100BT1_STAT2_ANGE      0x0008
 
+#define MDIO_MMD_PCS_MV_100BT1_INT_EN                  33042
+#define MDIO_MMD_PCS_MV_100BT1_INT_EN_LINKEVENT                0x0400
+
+#define MDIO_MMD_PCS_MV_COPPER_INT_STAT                        33043
+#define MDIO_MMD_PCS_MV_COPPER_INT_STAT_LINKEVENT      0x0400
+
 #define MDIO_MMD_PCS_MV_RX_STAT                        33328
 
 struct mmd_val {
@@ -99,13 +118,15 @@ static int mv88q2xxx_read_link_gbit(struct phy_device *phydev)
 
        /* Read vendor specific Auto-Negotiation status register to get local
         * and remote receiver status according to software initialization
-        * guide.
+        * guide. However, when not in polling mode the local and remote
+        * receiver status are not evaluated due to the Marvell 88Q2xxx APIs.
         */
        ret = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_MMD_AN_MV_STAT);
        if (ret < 0) {
                return ret;
-       } else if ((ret & MDIO_MMD_AN_MV_STAT_LOCAL_RX) &&
-                  (ret & MDIO_MMD_AN_MV_STAT_REMOTE_RX)) {
+       } else if (((ret & MDIO_MMD_AN_MV_STAT_LOCAL_RX) &&
+                  (ret & MDIO_MMD_AN_MV_STAT_REMOTE_RX)) ||
+                  !phy_polling_mode(phydev)) {
                /* The link state is latched low so that momentary link
                 * drops can be detected. Do not double-read the status
                 * in polling mode to detect such short link drops except
@@ -145,7 +166,18 @@ static int mv88q2xxx_read_link_100m(struct phy_device *phydev)
         * the link was already down. In case we are not polling,
         * we always read the realtime status.
         */
-       if (!phy_polling_mode(phydev) || !phydev->link) {
+       if (!phy_polling_mode(phydev)) {
+               phydev->link = false;
+               ret = phy_read_mmd(phydev, MDIO_MMD_PCS,
+                                  MDIO_MMD_PCS_MV_100BT1_STAT2);
+               if (ret < 0)
+                       return ret;
+
+               if (ret & MDIO_MMD_PCS_MV_100BT1_STAT2_LINK)
+                       phydev->link = true;
+
+               return 0;
+       } else if (!phydev->link) {
                ret = phy_read_mmd(phydev, MDIO_MMD_PCS,
                                   MDIO_MMD_PCS_MV_100BT1_STAT1);
                if (ret < 0)
@@ -356,6 +388,79 @@ static int mv88q2xxx_get_sqi_max(struct phy_device *phydev)
        return 15;
 }
 
+static int mv88q2xxx_config_intr(struct phy_device *phydev)
+{
+       int ret;
+
+       if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
+               /* Enable interrupts for 1000BASE-T1 link up and down events
+                * and enable general interrupts for 100BASE-T1.
+                */
+               ret = phy_write_mmd(phydev, MDIO_MMD_PCS,
+                                   MDIO_MMD_PCS_MV_INT_EN,
+                                   MDIO_MMD_PCS_MV_INT_EN_LINK_UP |
+                                   MDIO_MMD_PCS_MV_INT_EN_LINK_DOWN |
+                                   MDIO_MMD_PCS_MV_INT_EN_100BT1);
+               if (ret < 0)
+                       return ret;
+
+               /* Enable interrupts for 100BASE-T1 link events */
+               return phy_write_mmd(phydev, MDIO_MMD_PCS,
+                                    MDIO_MMD_PCS_MV_100BT1_INT_EN,
+                                    MDIO_MMD_PCS_MV_100BT1_INT_EN_LINKEVENT);
+       } else {
+               ret = phy_write_mmd(phydev, MDIO_MMD_PCS,
+                                   MDIO_MMD_PCS_MV_INT_EN, 0);
+               if (ret < 0)
+                       return ret;
+
+               return phy_write_mmd(phydev, MDIO_MMD_PCS,
+                                    MDIO_MMD_PCS_MV_100BT1_INT_EN, 0);
+       }
+}
+
+static irqreturn_t mv88q2xxx_handle_interrupt(struct phy_device *phydev)
+{
+       bool trigger_machine = false;
+       int irq;
+
+       /* Before we can acknowledge the 100BT1 general interrupt, that is in
+        * the 1000BT1 interrupt status register, we have to acknowledge any
+        * interrupts that are related to it. Therefore we read first the 100BT1
+        * interrupt status register, followed by reading the 1000BT1 interrupt
+        * status register.
+        */
+
+       irq = phy_read_mmd(phydev, MDIO_MMD_PCS,
+                          MDIO_MMD_PCS_MV_COPPER_INT_STAT);
+       if (irq < 0) {
+               phy_error(phydev);
+               return IRQ_NONE;
+       }
+
+       /* Check link status for 100BT1 */
+       if (irq & MDIO_MMD_PCS_MV_COPPER_INT_STAT_LINKEVENT)
+               trigger_machine = true;
+
+       irq = phy_read_mmd(phydev, MDIO_MMD_PCS, MDIO_MMD_PCS_MV_GPIO_INT_STAT);
+       if (irq < 0) {
+               phy_error(phydev);
+               return IRQ_NONE;
+       }
+
+       /* Check link status for 1000BT1 */
+       if ((irq & MDIO_MMD_PCS_MV_GPIO_INT_STAT_LINK_UP) ||
+           (irq & MDIO_MMD_PCS_MV_GPIO_INT_STAT_LINK_DOWN))
+               trigger_machine = true;
+
+       if (!trigger_machine)
+               return IRQ_NONE;
+
+       phy_trigger_machine(phydev);
+
+       return IRQ_HANDLED;
+}
+
 static int mv88q222x_soft_reset(struct phy_device *phydev)
 {
        int ret;
@@ -422,6 +527,14 @@ static int mv88q222x_revb0_config_init(struct phy_device *phydev)
         */
        phydev->pma_extable = MDIO_PMA_EXTABLE_BT1;
 
+       /* Configure interrupt with default settings, output is driven low for
+        * active interrupt and high for inactive.
+        */
+       if (phy_interrupt_is_valid(phydev))
+               return phy_set_bits_mmd(phydev, MDIO_MMD_PCS,
+                                       MDIO_MMD_PCS_MV_GPIO_INT_CTRL,
+                                       MDIO_MMD_PCS_MV_GPIO_INT_CTRL_TRI_DIS);
+
        return 0;
 }
 
@@ -448,6 +561,8 @@ static struct phy_driver mv88q2xxx_driver[] = {
                .config_init            = mv88q222x_revb0_config_init,
                .read_status            = mv88q2xxx_read_status,
                .soft_reset             = mv88q222x_soft_reset,
+               .config_intr            = mv88q2xxx_config_intr,
+               .handle_interrupt       = mv88q2xxx_handle_interrupt,
                .set_loopback           = genphy_c45_loopback,
                .get_sqi                = mv88q2xxx_get_sqi,
                .get_sqi_max            = mv88q2xxx_get_sqi_max,