Merge branch 'net-dsa-mv88e6xxx-accelerate-c45-scan'

Klaus Kudielka says:

====================
net: dsa: mv88e6xxx: accelerate C45 scan

Starting with commit 1a136ca2e089 ("net: mdio: scan bus based on bus
capabilities for C22 and C45"), mdiobus_scan_bus_c45() is being called on
buses with MDIOBUS_NO_CAP. On a Turris Omnia (Armada 385, 88E6176 switch),
this causes a significant increase of boot time, from 1.6 seconds, to 6.3
seconds. The boot time stated here is until start of /init.

Further testing revealed that the C45 scan is indeed expensive (around
2.7 seconds, due to a huge number of bus transactions), and called twice.

Two things were suggested:
(1) to move the expensive call of mv88e6xxx_mdios_register() from
    mv88e6xxx_probe() to mv88e6xxx_setup().
(2) to mask apparently non-existing phys during probing.

Before that:
Patch #1 prepares the driver to handle the movement of
mv88e6xxx_mdios_register() to mv88e6xxx_setup() for cross-chip DSA trees.
Patch #2 is preparatory code movement, without functional change.

With those changes, boot time on the Turris Omnia is back to normal.

Link: https://lore.kernel.org/lkml/449bde236c08d5ab5e54abd73b645d8b29955894.camel@gmail.com/
====================

Link: https://lore.kernel.org/r/20230315163846.3114-1-klaus.kudielka@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

2 files changed, 196 insertions, 205 deletions

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index 30383c4f8fd0..260e38c5c6e6 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -3680,185 +3680,6 @@ static int mv88e6390_setup_errata(struct mv88e6xxx_chip *chip)
 	return mv88e6xxx_software_reset(chip);
 }
 
-static void mv88e6xxx_teardown(struct dsa_switch *ds)
-{
-	mv88e6xxx_teardown_devlink_params(ds);
-	dsa_devlink_resources_unregister(ds);
-	mv88e6xxx_teardown_devlink_regions_global(ds);
-}
-
-static int mv88e6xxx_setup(struct dsa_switch *ds)
-{
-	struct mv88e6xxx_chip *chip = ds->priv;
-	u8 cmode;
-	int err;
-	int i;
-
-	chip->ds = ds;
-	ds->slave_mii_bus = mv88e6xxx_default_mdio_bus(chip);
-
-	/* Since virtual bridges are mapped in the PVT, the number we support
-	 * depends on the physical switch topology. We need to let DSA figure
-	 * that out and therefore we cannot set this at dsa_register_switch()
-	 * time.
-	 */
-	if (mv88e6xxx_has_pvt(chip))
-		ds->max_num_bridges = MV88E6XXX_MAX_PVT_SWITCHES -
-				      ds->dst->last_switch - 1;
-
-	mv88e6xxx_reg_lock(chip);
-
-	if (chip->info->ops->setup_errata) {
-		err = chip->info->ops->setup_errata(chip);
-		if (err)
-			goto unlock;
-	}
-
-	/* Cache the cmode of each port. */
-	for (i = 0; i < mv88e6xxx_num_ports(chip); i++) {
-		if (chip->info->ops->port_get_cmode) {
-			err = chip->info->ops->port_get_cmode(chip, i, &cmode);
-			if (err)
-				goto unlock;
-
-			chip->ports[i].cmode = cmode;
-		}
-	}
-
-	err = mv88e6xxx_vtu_setup(chip);
-	if (err)
-		goto unlock;
-
-	/* Must be called after mv88e6xxx_vtu_setup (which flushes the
-	 * VTU, thereby also flushing the STU).
-	 */
-	err = mv88e6xxx_stu_setup(chip);
-	if (err)
-		goto unlock;
-
-	/* Setup Switch Port Registers */
-	for (i = 0; i < mv88e6xxx_num_ports(chip); i++) {
-		if (dsa_is_unused_port(ds, i))
-			continue;
-
-		/* Prevent the use of an invalid port. */
-		if (mv88e6xxx_is_invalid_port(chip, i)) {
-			dev_err(chip->dev, "port %d is invalid\n", i);
-			err = -EINVAL;
-			goto unlock;
-		}
-
-		err = mv88e6xxx_setup_port(chip, i);
-		if (err)
-			goto unlock;
-	}
-
-	err = mv88e6xxx_irl_setup(chip);
-	if (err)
-		goto unlock;
-
-	err = mv88e6xxx_mac_setup(chip);
-	if (err)
-		goto unlock;
-
-	err = mv88e6xxx_phy_setup(chip);
-	if (err)
-		goto unlock;
-
-	err = mv88e6xxx_pvt_setup(chip);
-	if (err)
-		goto unlock;
-
-	err = mv88e6xxx_atu_setup(chip);
-	if (err)
-		goto unlock;
-
-	err = mv88e6xxx_broadcast_setup(chip, 0);
-	if (err)
-		goto unlock;
-
-	err = mv88e6xxx_pot_setup(chip);
-	if (err)
-		goto unlock;
-
-	err = mv88e6xxx_rmu_setup(chip);
-	if (err)
-		goto unlock;
-
-	err = mv88e6xxx_rsvd2cpu_setup(chip);
-	if (err)
-		goto unlock;
-
-	err = mv88e6xxx_trunk_setup(chip);
-	if (err)
-		goto unlock;
-
-	err = mv88e6xxx_devmap_setup(chip);
-	if (err)
-		goto unlock;
-
-	err = mv88e6xxx_pri_setup(chip);
-	if (err)
-		goto unlock;
-
-	/* Setup PTP Hardware Clock and timestamping */
-	if (chip->info->ptp_support) {
-		err = mv88e6xxx_ptp_setup(chip);
-		if (err)
-			goto unlock;
-
-		err = mv88e6xxx_hwtstamp_setup(chip);
-		if (err)
-			goto unlock;
-	}
-
-	err = mv88e6xxx_stats_setup(chip);
-	if (err)
-		goto unlock;
-
-unlock:
-	mv88e6xxx_reg_unlock(chip);
-
-	if (err)
-		return err;
-
-	/* Have to be called without holding the register lock, since
-	 * they take the devlink lock, and we later take the locks in
-	 * the reverse order when getting/setting parameters or
-	 * resource occupancy.
-	 */
-	err = mv88e6xxx_setup_devlink_resources(ds);
-	if (err)
-		return err;
-
-	err = mv88e6xxx_setup_devlink_params(ds);
-	if (err)
-		goto out_resources;
-
-	err = mv88e6xxx_setup_devlink_regions_global(ds);
-	if (err)
-		goto out_params;
-
-	return 0;
-
-out_params:
-	mv88e6xxx_teardown_devlink_params(ds);
-out_resources:
-	dsa_devlink_resources_unregister(ds);
-
-	return err;
-}
-
-static int mv88e6xxx_port_setup(struct dsa_switch *ds, int port)
-{
-	return mv88e6xxx_setup_devlink_regions_port(ds, port);
-}
-
-static void mv88e6xxx_port_teardown(struct dsa_switch *ds, int port)
-{
-	mv88e6xxx_teardown_devlink_regions_port(ds, port);
-}
-
 /* prod_id for switch families which do not have a PHY model number */
 static const u16 family_prod_id_table[] = {
 	[MV88E6XXX_FAMILY_6341] = MV88E6XXX_PORT_SWITCH_ID_PROD_6341,
@@ -3984,6 +3805,7 @@ static int mv88e6xxx_mdio_register(struct mv88e6xxx_chip *chip,
 	bus->read_c45 = mv88e6xxx_mdio_read_c45;
 	bus->write_c45 = mv88e6xxx_mdio_write_c45;
 	bus->parent = chip->dev;
+	bus->phy_mask = GENMASK(31, mv88e6xxx_num_ports(chip));
 
 	if (!external) {
 		err = mv88e6xxx_g2_irq_mdio_setup(chip, bus);
@@ -4027,9 +3849,9 @@ static void mv88e6xxx_mdios_unregister(struct mv88e6xxx_chip *chip)
 	}
 }
 
-static int mv88e6xxx_mdios_register(struct mv88e6xxx_chip *chip,
-				    struct device_node *np)
+static int mv88e6xxx_mdios_register(struct mv88e6xxx_chip *chip)
 {
+	struct device_node *np = chip->dev->of_node;
 	struct device_node *child;
 	int err;
 
@@ -4062,6 +3884,194 @@ static int mv88e6xxx_mdios_register(struct mv88e6xxx_chip *chip,
 	return 0;
 }
 
+static void mv88e6xxx_teardown(struct dsa_switch *ds)
+{
+	struct mv88e6xxx_chip *chip = ds->priv;
+
+	mv88e6xxx_teardown_devlink_params(ds);
+	dsa_devlink_resources_unregister(ds);
+	mv88e6xxx_teardown_devlink_regions_global(ds);
+	mv88e6xxx_mdios_unregister(chip);
+}
+
+static int mv88e6xxx_setup(struct dsa_switch *ds)
+{
+	struct mv88e6xxx_chip *chip = ds->priv;
+	u8 cmode;
+	int err;
+	int i;
+
+	err = mv88e6xxx_mdios_register(chip);
+	if (err)
+		return err;
+
+	chip->ds = ds;
+	ds->slave_mii_bus = mv88e6xxx_default_mdio_bus(chip);
+
+	/* Since virtual bridges are mapped in the PVT, the number we support
+	 * depends on the physical switch topology. We need to let DSA figure
+	 * that out and therefore we cannot set this at dsa_register_switch()
+	 * time.
+	 */
+	if (mv88e6xxx_has_pvt(chip))
+		ds->max_num_bridges = MV88E6XXX_MAX_PVT_SWITCHES -
+				      ds->dst->last_switch - 1;
+
+	mv88e6xxx_reg_lock(chip);
+
+	if (chip->info->ops->setup_errata) {
+		err = chip->info->ops->setup_errata(chip);
+		if (err)
+			goto unlock;
+	}
+
+	/* Cache the cmode of each port. */
+	for (i = 0; i < mv88e6xxx_num_ports(chip); i++) {
+		if (chip->info->ops->port_get_cmode) {
+			err = chip->info->ops->port_get_cmode(chip, i, &cmode);
+			if (err)
+				goto unlock;
+
+			chip->ports[i].cmode = cmode;
+		}
+	}
+
+	err = mv88e6xxx_vtu_setup(chip);
+	if (err)
+		goto unlock;
+
+	/* Must be called after mv88e6xxx_vtu_setup (which flushes the
+	 * VTU, thereby also flushing the STU).
+	 */
+	err = mv88e6xxx_stu_setup(chip);
+	if (err)
+		goto unlock;
+
+	/* Setup Switch Port Registers */
+	for (i = 0; i < mv88e6xxx_num_ports(chip); i++) {
+		if (dsa_is_unused_port(ds, i))
+			continue;
+
+		/* Prevent the use of an invalid port. */
+		if (mv88e6xxx_is_invalid_port(chip, i)) {
+			dev_err(chip->dev, "port %d is invalid\n", i);
+			err = -EINVAL;
+			goto unlock;
+		}
+
+		err = mv88e6xxx_setup_port(chip, i);
+		if (err)
+			goto unlock;
+	}
+
+	err = mv88e6xxx_irl_setup(chip);
+	if (err)
+		goto unlock;
+
+	err = mv88e6xxx_mac_setup(chip);
+	if (err)
+		goto unlock;
+
+	err = mv88e6xxx_phy_setup(chip);
+	if (err)
+		goto unlock;
+
+	err = mv88e6xxx_pvt_setup(chip);
+	if (err)
+		goto unlock;
+
+	err = mv88e6xxx_atu_setup(chip);
+	if (err)
+		goto unlock;
+
+	err = mv88e6xxx_broadcast_setup(chip, 0);
+	if (err)
+		goto unlock;
+
+	err = mv88e6xxx_pot_setup(chip);
+	if (err)
+		goto unlock;
+
+	err = mv88e6xxx_rmu_setup(chip);
+	if (err)
+		goto unlock;
+
+	err = mv88e6xxx_rsvd2cpu_setup(chip);
+	if (err)
+		goto unlock;
+
+	err = mv88e6xxx_trunk_setup(chip);
+	if (err)
+		goto unlock;
+
+	err = mv88e6xxx_devmap_setup(chip);
+	if (err)
+		goto unlock;
+
+	err = mv88e6xxx_pri_setup(chip);
+	if (err)
+		goto unlock;
+
+	/* Setup PTP Hardware Clock and timestamping */
+	if (chip->info->ptp_support) {
+		err = mv88e6xxx_ptp_setup(chip);
+		if (err)
+			goto unlock;
+
+		err = mv88e6xxx_hwtstamp_setup(chip);
+		if (err)
+			goto unlock;
+	}
+
+	err = mv88e6xxx_stats_setup(chip);
+	if (err)
+		goto unlock;
+
+unlock:
+	mv88e6xxx_reg_unlock(chip);
+
+	if (err)
+		goto out_mdios;
+
+	/* Have to be called without holding the register lock, since
+	 * they take the devlink lock, and we later take the locks in
+	 * the reverse order when getting/setting parameters or
+	 * resource occupancy.
+	 */
+	err = mv88e6xxx_setup_devlink_resources(ds);
+	if (err)
+		goto out_mdios;
+
+	err = mv88e6xxx_setup_devlink_params(ds);
+	if (err)
+		goto out_resources;
+
+	err = mv88e6xxx_setup_devlink_regions_global(ds);
+	if (err)
+		goto out_params;
+
+	return 0;
+
+out_params:
+	mv88e6xxx_teardown_devlink_params(ds);
+out_resources:
+	dsa_devlink_resources_unregister(ds);
+out_mdios:
+	mv88e6xxx_mdios_unregister(chip);
+
+	return err;
+}
+
+static int mv88e6xxx_port_setup(struct dsa_switch *ds, int port)
+{
+	return mv88e6xxx_setup_devlink_regions_port(ds, port);
+}
+
+static void mv88e6xxx_port_teardown(struct dsa_switch *ds, int port)
+{
+	mv88e6xxx_teardown_devlink_regions_port(ds, port);
+}
+
 static int mv88e6xxx_get_eeprom_len(struct dsa_switch *ds)
 {
 	struct mv88e6xxx_chip *chip = ds->priv;
@@ -7228,18 +7238,12 @@ static int mv88e6xxx_probe(struct mdio_device *mdiodev)
 	if (err)
 		goto out_g1_atu_prob_irq;
 
-	err = mv88e6xxx_mdios_register(chip, np);
-	if (err)
-		goto out_g1_vtu_prob_irq;
-
 	err = mv88e6xxx_register_switch(chip);
 	if (err)
-		goto out_mdio;
+		goto out_g1_vtu_prob_irq;
 
 	return 0;
 
-out_mdio:
-	mv88e6xxx_mdios_unregister(chip);
 out_g1_vtu_prob_irq:
 	mv88e6xxx_g1_vtu_prob_irq_free(chip);
 out_g1_atu_prob_irq:
@@ -7276,7 +7280,6 @@ static void mv88e6xxx_remove(struct mdio_device *mdiodev)
 
 	mv88e6xxx_phy_destroy(chip);
 	mv88e6xxx_unregister_switch(chip);
-	mv88e6xxx_mdios_unregister(chip);
 
 	mv88e6xxx_g1_vtu_prob_irq_free(chip);
 	mv88e6xxx_g1_atu_prob_irq_free(chip);
diff --git a/drivers/net/dsa/mv88e6xxx/global2.c b/drivers/net/dsa/mv88e6xxx/global2.c
index ed3b2f88e783..a26546d3d7b5 100644
--- a/drivers/net/dsa/mv88e6xxx/global2.c
+++ b/drivers/net/dsa/mv88e6xxx/global2.c
@@ -1176,31 +1176,19 @@ out:
 int mv88e6xxx_g2_irq_mdio_setup(struct mv88e6xxx_chip *chip,
 				struct mii_bus *bus)
 {
-	int phy, irq, err, err_phy;
+	int phy, irq;
 
 	for (phy = 0; phy < chip->info->num_internal_phys; phy++) {
 		irq = irq_find_mapping(chip->g2_irq.domain, phy);
-		if (irq < 0) {
-			err = irq;
-			goto out;
-		}
+		if (irq < 0)
+			return irq;
+
 		bus->irq[chip->info->phy_base_addr + phy] = irq;
 	}
 	return 0;
-out:
-	err_phy = phy;
-
-	for (phy = 0; phy < err_phy; phy++)
-		irq_dispose_mapping(bus->irq[phy]);
-
-	return err;
 }
 
 void mv88e6xxx_g2_irq_mdio_free(struct mv88e6xxx_chip *chip,
 				struct mii_bus *bus)
 {
-	int phy;
-
-	for (phy = 0; phy < chip->info->num_internal_phys; phy++)
-		irq_dispose_mapping(bus->irq[phy]);
 }