1 files changed, 174 insertions, 0 deletions

diff --git a/drivers/net/ethernet/ti/am65-cpsw-qos.c b/drivers/net/ethernet/ti/am65-cpsw-qos.c
index 7790d739e74e..816e73a3d6e4 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-qos.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-qos.c
@@ -4,6 +4,7 @@
  *
  * quality of service module includes:
  * Enhanced Scheduler Traffic (EST - P802.1Qbv/D2.2)
+ * Interspersed Express Traffic (IET - P802.3br/D2.0)
  */
 
 #include <linux/pm_runtime.h>
@@ -25,6 +26,8 @@ enum timer_act {
 	TACT_SKIP_PROG,		/* just buffer can be updated */
 };
 
+static void am65_cpsw_iet_change_preemptible_tcs(struct am65_cpsw_port *port, u8 preemptible_tcs);
+
 static u32
 am65_cpsw_qos_tx_rate_calc(u32 rate_mbps, unsigned long bus_freq)
 {
@@ -192,6 +195,8 @@ static void am65_cpsw_reset_tc_mqprio(struct net_device *ndev)
 
 	/* Reset all Queue priorities to 0 */
 	writel(0, port->port_base + AM65_CPSW_PN_REG_TX_PRI_MAP);
+
+	am65_cpsw_iet_change_preemptible_tcs(port, 0);
 }
 
 static int am65_cpsw_setup_mqprio(struct net_device *ndev, void *type_data)
@@ -254,6 +259,7 @@ static int am65_cpsw_setup_mqprio(struct net_device *ndev, void *type_data)
 	writel(tx_prio_map, port->port_base + AM65_CPSW_PN_REG_TX_PRI_MAP);
 
 	am65_cpsw_tx_pn_shaper_apply(port);
+	am65_cpsw_iet_change_preemptible_tcs(port, mqprio->preemptible_tcs);
 
 exit_put:
 	pm_runtime_put(common->dev);
@@ -261,6 +267,171 @@ exit_put:
 	return ret;
 }
 
+static int am65_cpsw_iet_set_verify_timeout_count(struct am65_cpsw_port *port)
+{
+	int verify_time_ms = port->qos.iet.verify_time_ms;
+	u32 val;
+
+	/* The number of wireside clocks contained in the verify
+	 * timeout counter. The default is 0x1312d0
+	 * (10ms at 125Mhz in 1G mode).
+	 */
+	val = 125 * HZ_PER_MHZ;	/* assuming 125MHz wireside clock */
+
+	val /= MILLIHZ_PER_HZ;		/* count per ms timeout */
+	val *= verify_time_ms;		/* count for timeout ms */
+
+	if (val > AM65_CPSW_PN_MAC_VERIFY_CNT_MASK)
+		return -EINVAL;
+
+	writel(val, port->port_base + AM65_CPSW_PN_REG_IET_VERIFY);
+
+	return 0;
+}
+
+static int am65_cpsw_iet_verify_wait(struct am65_cpsw_port *port)
+{
+	u32 ctrl, status;
+	int try;
+
+	try = 20;
+	do {
+		/* Reset the verify state machine by writing 1
+		 * to LINKFAIL
+		 */
+		ctrl = readl(port->port_base + AM65_CPSW_PN_REG_IET_CTRL);
+		ctrl |= AM65_CPSW_PN_IET_MAC_LINKFAIL;
+		writel(ctrl, port->port_base + AM65_CPSW_PN_REG_IET_CTRL);
+
+		/* Clear MAC_LINKFAIL bit to start Verify. */
+		ctrl = readl(port->port_base + AM65_CPSW_PN_REG_IET_CTRL);
+		ctrl &= ~AM65_CPSW_PN_IET_MAC_LINKFAIL;
+		writel(ctrl, port->port_base + AM65_CPSW_PN_REG_IET_CTRL);
+
+		msleep(port->qos.iet.verify_time_ms);
+
+		status = readl(port->port_base + AM65_CPSW_PN_REG_IET_STATUS);
+		if (status & AM65_CPSW_PN_MAC_VERIFIED)
+			return 0;
+
+		if (status & AM65_CPSW_PN_MAC_VERIFY_FAIL) {
+			netdev_dbg(port->ndev,
+				   "MAC Merge verify failed, trying again\n");
+			continue;
+		}
+
+		if (status & AM65_CPSW_PN_MAC_RESPOND_ERR) {
+			netdev_dbg(port->ndev, "MAC Merge respond error\n");
+			return -ENODEV;
+		}
+
+		if (status & AM65_CPSW_PN_MAC_VERIFY_ERR) {
+			netdev_dbg(port->ndev, "MAC Merge verify error\n");
+			return -ENODEV;
+		}
+	} while (try-- > 0);
+
+	netdev_dbg(port->ndev, "MAC Merge verify timeout\n");
+	return -ETIMEDOUT;
+}
+
+static void am65_cpsw_iet_set_preempt_mask(struct am65_cpsw_port *port, u8 preemptible_tcs)
+{
+	u32 val;
+
+	val = readl(port->port_base + AM65_CPSW_PN_REG_IET_CTRL);
+	val &= ~AM65_CPSW_PN_IET_MAC_PREMPT_MASK;
+	val |= AM65_CPSW_PN_IET_MAC_SET_PREEMPT(preemptible_tcs);
+	writel(val, port->port_base + AM65_CPSW_PN_REG_IET_CTRL);
+}
+
+/* enable common IET_ENABLE only if at least 1 port has rx IET enabled.
+ * UAPI doesn't allow tx enable without rx enable.
+ */
+void am65_cpsw_iet_common_enable(struct am65_cpsw_common *common)
+{
+	struct am65_cpsw_port *port;
+	bool rx_enable = false;
+	u32 val;
+	int i;
+
+	for (i = 0; i < common->port_num; i++) {
+		port = &common->ports[i];
+		val = readl(port->port_base + AM65_CPSW_PN_REG_CTL);
+		rx_enable = !!(val & AM65_CPSW_PN_CTL_IET_PORT_EN);
+		if (rx_enable)
+			break;
+	}
+
+	val = readl(common->cpsw_base + AM65_CPSW_REG_CTL);
+
+	if (rx_enable)
+		val |= AM65_CPSW_CTL_IET_EN;
+	else
+		val &= ~AM65_CPSW_CTL_IET_EN;
+
+	writel(val, common->cpsw_base + AM65_CPSW_REG_CTL);
+	common->iet_enabled = rx_enable;
+}
+
+/* CPSW does not have an IRQ to notify changes to the MAC Merge TX status
+ * (active/inactive), but the preemptible traffic classes should only be
+ * committed to hardware once TX is active. Resort to polling.
+ */
+void am65_cpsw_iet_commit_preemptible_tcs(struct am65_cpsw_port *port)
+{
+	u8 preemptible_tcs;
+	int err;
+	u32 val;
+
+	if (port->qos.link_speed == SPEED_UNKNOWN)
+		return;
+
+	val = readl(port->port_base + AM65_CPSW_PN_REG_CTL);
+	if (!(val & AM65_CPSW_PN_CTL_IET_PORT_EN))
+		return;
+
+	/* update common IET enable */
+	am65_cpsw_iet_common_enable(port->common);
+
+	/* update verify count */
+	err = am65_cpsw_iet_set_verify_timeout_count(port);
+	if (err) {
+		netdev_err(port->ndev, "couldn't set verify count: %d\n", err);
+		return;
+	}
+
+	val = readl(port->port_base + AM65_CPSW_PN_REG_IET_CTRL);
+	if (!(val & AM65_CPSW_PN_IET_MAC_DISABLEVERIFY)) {
+		err = am65_cpsw_iet_verify_wait(port);
+		if (err)
+			return;
+	}
+
+	preemptible_tcs = port->qos.iet.preemptible_tcs;
+	am65_cpsw_iet_set_preempt_mask(port, preemptible_tcs);
+}
+
+static void am65_cpsw_iet_change_preemptible_tcs(struct am65_cpsw_port *port, u8 preemptible_tcs)
+{
+	struct am65_cpsw_ndev_priv *priv = am65_ndev_to_priv(port->ndev);
+
+	port->qos.iet.preemptible_tcs = preemptible_tcs;
+	mutex_lock(&priv->mm_lock);
+	am65_cpsw_iet_commit_preemptible_tcs(port);
+	mutex_unlock(&priv->mm_lock);
+}
+
+static void am65_cpsw_iet_link_state_update(struct net_device *ndev)
+{
+	struct am65_cpsw_ndev_priv *priv = am65_ndev_to_priv(ndev);
+	struct am65_cpsw_port *port = am65_ndev_to_port(ndev);
+
+	mutex_lock(&priv->mm_lock);
+	am65_cpsw_iet_commit_preemptible_tcs(port);
+	mutex_unlock(&priv->mm_lock);
+}
+
 static int am65_cpsw_port_est_enabled(struct am65_cpsw_port *port)
 {
 	return port->qos.est_oper || port->qos.est_admin;
@@ -737,6 +908,7 @@ static int am65_cpsw_taprio_replace(struct net_device *ndev,
 
 	devm_kfree(&ndev->dev, port->qos.est_admin);
 	port->qos.est_admin = est_new;
+	am65_cpsw_iet_change_preemptible_tcs(port, taprio->mqprio.preemptible_tcs);
 
 	return 0;
 
@@ -1116,6 +1288,7 @@ void am65_cpsw_qos_link_up(struct net_device *ndev, int link_speed)
 
 	port->qos.link_speed = link_speed;
 	am65_cpsw_tx_pn_shaper_apply(port);
+	am65_cpsw_iet_link_state_update(ndev);
 
 	am65_cpsw_est_link_up(ndev, link_speed);
 	port->qos.link_down_time = 0;
@@ -1127,6 +1300,7 @@ void am65_cpsw_qos_link_down(struct net_device *ndev)
 
 	port->qos.link_speed = SPEED_UNKNOWN;
 	am65_cpsw_tx_pn_shaper_apply(port);
+	am65_cpsw_iet_link_state_update(ndev);
 
 	if (!port->qos.link_down_time)
 		port->qos.link_down_time = ktime_get();