[PATCH net-next v4 0/4] net: dsa: mv88e6xxx: accelerate C45 scan

[PATCH net-next v4 0/4] net: dsa: mv88e6xxx: accelerate C45 scan

[Klaus Kudielka]

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/

v2:
Add cover letter
Extend the cleanup in mv88e6xxx_setup() to remove the mdio bus on failure 
Add patch "mask apparently non-existing phys during probing"

v3:
Add patch "don't dispose of Global2 IRQ mappings from mdiobus code"

v4:
Resubmit, this time hopefully with all subject prefixes correct
 
Klaus Kudielka (3):
  net: dsa: mv88e6xxx: re-order functions
  net: dsa: mv88e6xxx: move call to mv88e6xxx_mdios_register()
  net: dsa: mv88e6xxx: mask apparently non-existing phys during probing

Vladimir Oltean (1):
  net: dsa: mv88e6xxx: don't dispose of Global2 IRQ mappings from
    mdiobus code

 drivers/net/dsa/mv88e6xxx/chip.c    | 381 ++++++++++++++--------------
 drivers/net/dsa/mv88e6xxx/global2.c |  20 +-
 2 files changed, 196 insertions(+), 205 deletions(-)

-- 
2.39.2

[PATCH net-next v4 1/4] net: dsa: mv88e6xxx: don't dispose of Global2 IRQ mappings from mdiobus code

[Klaus Kudielka]

From: Vladimir Oltean <vladimir.oltean@nxp.com>

irq_find_mapping() does not need irq_dispose_mapping(), only
irq_create_mapping() does.

Calling irq_dispose_mapping() from mv88e6xxx_g2_irq_mdio_free() and from
the error path of mv88e6xxx_g2_irq_mdio_setup() effectively means that
the mdiobus logic (for internal PHY interrupts) is disposing of a
hwirq->virq mapping which it is not responsible of (but instead, the
function pair mv88e6xxx_g2_irq_setup() + mv88e6xxx_g2_irq_free() is).

With the current code structure, this isn't such a huge problem, because
mv88e6xxx_g2_irq_mdio_free() is called relatively close to the real
owner of the IRQ mappings:

mv88e6xxx_remove()
-> mv88e6xxx_unregister_switch()
-> mv88e6xxx_mdios_unregister()
   -> mv88e6xxx_g2_irq_mdio_free()
-> mv88e6xxx_g2_irq_free()

and the switch isn't 'live' in any way such that it would be able of
generating interrupts at this point (mv88e6xxx_unregister_switch() has
been called).

However, there is a desire to split mv88e6xxx_mdios_unregister() and
mv88e6xxx_g2_irq_free() such that mv88e6xxx_mdios_unregister() only gets
called from mv88e6xxx_teardown(). This is much more problematic, as can
be seen below.

In a cross-chip scenario (say 3 switches d0032004.mdio-mii:10,
d0032004.mdio-mii:11 and d0032004.mdio-mii:12 which form a single DSA
tree), it is possible to unbind the device driver from a single switch
(say d0032004.mdio-mii:10).

When that happens, mv88e6xxx_remove() will be called for just that one
switch, and this will call mv88e6xxx_unregister_switch() which will tear
down the entire tree (calling mv88e6xxx_teardown() for all 3 switches).

Assuming mv88e6xxx_mdios_unregister() was moved to mv88e6xxx_teardown(),
at this stage, all 3 switches will have called irq_dispose_mapping() on
their mdiobus virqs.

When we bind again the device driver to d0032004.mdio-mii:10,
mv88e6xxx_probe() is called for it, which calls dsa_register_switch().
The DSA tree is now complete again, and mv88e6xxx_setup() is called for
all 3 switches.

Also assuming that mv88e6xxx_mdios_register() is moved to
mv88e6xxx_setup() (the 2 assumptions go together), at this point,
d0032004.mdio-mii:11 and d0032004.mdio-mii:12 don't have an IRQ mapping
for the internal PHYs anymore, as they've disposed of it in
mv88e6xxx_teardown(). Whereas switch d0032004.mdio-mii:10 has re-created
it, because its code path comes from mv88e6xxx_probe().

Simply put, this change prepares the driver to handle the movement of
mv88e6xxx_mdios_register() to mv88e6xxx_setup() for cross-chip DSA trees.

Also, the code being deleted was partially wrong anyway (in a way which
may have hidden this other issue). mv88e6xxx_g2_irq_mdio_setup()
populates bus->irq[] starting with offset chip->info->phy_base_addr, but
the teardown path doesn't apply that offset too. So it disposes of virq
0 for phy = [ 0, phy_base_addr ).

All switch families have phy_base_addr = 0, except for MV88E6141 and
MV88E6341 which have it as 0x10. I guess those families would have
happened to work by mistake in cross-chip scenarios too.

I'm deleting the body of mv88e6xxx_g2_irq_mdio_free() but leaving its
call sites and prototype in place. This is because, if we ever need to
add back some teardown procedure in the future, it will be perhaps
error-prone to deduce the proper call sites again. Whereas like this,
no extra code should get generated, it shouldn't bother anybody.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
---

Notes:
    v3: Patch is new

 drivers/net/dsa/mv88e6xxx/global2.c | 20 ++++----------------
 1 file changed, 4 insertions(+), 16 deletions(-)

diff --git a/drivers/net/dsa/mv88e6xxx/global2.c b/drivers/net/dsa/mv88e6xxx/global2.c
index ed3b2f88e7..a26546d3d7 100644
--- a/drivers/net/dsa/mv88e6xxx/global2.c
+++ b/drivers/net/dsa/mv88e6xxx/global2.c
@@ -1176,31 +1176,19 @@ int mv88e6xxx_g2_irq_setup(struct mv88e6xxx_chip *chip)
 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]);
 }
-- 
2.39.2

[PATCH net-next v4 2/4] net: dsa: mv88e6xxx: re-order functions

[Klaus Kudielka]

Move mv88e6xxx_setup() below mv88e6xxx_mdios_register(), so that we are
able to call the latter one from here. Do the same thing for the
inverse functions.

Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
---
 drivers/net/dsa/mv88e6xxx/chip.c | 358 +++++++++++++++----------------
 1 file changed, 179 insertions(+), 179 deletions(-)

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index 0a5d6c7bb1..496015baac 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -3672,185 +3672,6 @@ 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,
@@ -4054,6 +3875,185 @@ static int mv88e6xxx_mdios_register(struct mv88e6xxx_chip *chip,
 	return 0;
 }
 
+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);
+}
+
 static int mv88e6xxx_get_eeprom_len(struct dsa_switch *ds)
 {
 	struct mv88e6xxx_chip *chip = ds->priv;
-- 
2.39.2

[PATCH net-next v4 3/4] net: dsa: mv88e6xxx: move call to mv88e6xxx_mdios_register()

[Klaus Kudielka]

Call the rather expensive mv88e6xxx_mdios_register() at the beginning of
mv88e6xxx_setup(). This avoids the double call via mv88e6xxx_probe()
during boot.

For symmetry, call mv88e6xxx_mdios_unregister() at the end of
mv88e6xxx_teardown().

Link: https://lore.kernel.org/lkml/449bde236c08d5ab5e54abd73b645d8b29955894.camel@gmail.com/
Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
---

Notes:
    v2: Extend the cleanup in mv88e6xxx_setup() to remove the mdio bus on failure

 drivers/net/dsa/mv88e6xxx/chip.c | 26 ++++++++++++++------------
 1 file changed, 14 insertions(+), 12 deletions(-)

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index 496015baac..29b0f3bb1c 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -3840,9 +3840,9 @@ 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;
 
@@ -3877,9 +3877,12 @@ static int mv88e6xxx_mdios_register(struct mv88e6xxx_chip *chip,
 
 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)
@@ -3889,6 +3892,10 @@ static int mv88e6xxx_setup(struct dsa_switch *ds)
 	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);
 
@@ -4015,7 +4022,7 @@ static int mv88e6xxx_setup(struct dsa_switch *ds)
 	mv88e6xxx_reg_unlock(chip);
 
 	if (err)
-		return 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
@@ -4024,7 +4031,7 @@ static int mv88e6xxx_setup(struct dsa_switch *ds)
 	 */
 	err = mv88e6xxx_setup_devlink_resources(ds);
 	if (err)
-		return err;
+		goto out_mdios;
 
 	err = mv88e6xxx_setup_devlink_params(ds);
 	if (err)
@@ -4040,6 +4047,8 @@ static int mv88e6xxx_setup(struct dsa_switch *ds)
 	mv88e6xxx_teardown_devlink_params(ds);
 out_resources:
 	dsa_devlink_resources_unregister(ds);
+out_mdios:
+	mv88e6xxx_mdios_unregister(chip);
 
 	return err;
 }
@@ -7220,18 +7229,12 @@ 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:
@@ -7268,7 +7271,6 @@ 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);
-- 
2.39.2

[PATCH net-next v4 4/4] net: dsa: mv88e6xxx: mask apparently non-existing phys during probing

[Klaus Kudielka]

To avoid excessive mdio bus transactions during probing, mask all phy
addresses that do not exist (there is a 1:1 mapping between switch port
number and phy address).

Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
---

Notes:
    v2: Patch is new

 drivers/net/dsa/mv88e6xxx/chip.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index 29b0f3bb1c..c52798d9ce 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -3797,6 +3797,7 @@ 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);
-- 
2.39.2

Re: [PATCH net-next v4 1/4] net: dsa: mv88e6xxx: don't dispose of Global2 IRQ mappings from mdiobus code

[Vladimir Oltean]

On Wed, Mar 15, 2023 at 05:38:43PM +0100, Klaus Kudielka wrote:
> From: Vladimir Oltean <vladimir.oltean@nxp.com>
> 
> Simply put, this change prepares the driver to handle the movement of
> mv88e6xxx_mdios_register() to mv88e6xxx_setup() for cross-chip DSA trees.
> 
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
> Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
> ---

Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>

No point in adding my Reviewed-by tag, since I wrote this patch...

Re: [PATCH net-next v4 2/4] net: dsa: mv88e6xxx: re-order functions

[Vladimir Oltean]

On Wed, Mar 15, 2023 at 05:38:44PM +0100, Klaus Kudielka wrote:
> Move mv88e6xxx_setup() below mv88e6xxx_mdios_register(), so that we are
> able to call the latter one from here. Do the same thing for the
> inverse functions.
> 
> Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>
> ---

Reviewed-by: Vladimir Oltean <olteanv@gmail.com>

Re: [PATCH net-next v4 3/4] net: dsa: mv88e6xxx: move call to mv88e6xxx_mdios_register()

[Vladimir Oltean]

On Wed, Mar 15, 2023 at 05:38:45PM +0100, Klaus Kudielka wrote:
> Call the rather expensive mv88e6xxx_mdios_register() at the beginning of
> mv88e6xxx_setup(). This avoids the double call via mv88e6xxx_probe()
> during boot.
> 
> For symmetry, call mv88e6xxx_mdios_unregister() at the end of
> mv88e6xxx_teardown().
> 
> Link: https://lore.kernel.org/lkml/449bde236c08d5ab5e54abd73b645d8b29955894.camel@gmail.com/
> Suggested-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>
> ---

Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com>

Re: [PATCH net-next v4 4/4] net: dsa: mv88e6xxx: mask apparently non-existing phys during probing

[Vladimir Oltean]

On Wed, Mar 15, 2023 at 05:38:46PM +0100, Klaus Kudielka wrote:
> To avoid excessive mdio bus transactions during probing, mask all phy
> addresses that do not exist (there is a 1:1 mapping between switch port
> number and phy address).
> 
> Suggested-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>
> ---

Reviewed-by: Vladimir Oltean <olteanv@gmail.com>

Note that on Turris MOX, the PHYs are described in the device tree, so
the MDIO bus is not auto-scanned and this patch has no effect, therefore
I won't add my Tested-by tag here.

Re: [PATCH net-next v4 1/4] net: dsa: mv88e6xxx: don't dispose of Global2 IRQ mappings from mdiobus code

[Florian Fainelli]

On 3/15/23 09:38, Klaus Kudielka wrote:
> From: Vladimir Oltean <vladimir.oltean@nxp.com>
> 
> irq_find_mapping() does not need irq_dispose_mapping(), only
> irq_create_mapping() does.
> 
> Calling irq_dispose_mapping() from mv88e6xxx_g2_irq_mdio_free() and from
> the error path of mv88e6xxx_g2_irq_mdio_setup() effectively means that
> the mdiobus logic (for internal PHY interrupts) is disposing of a
> hwirq->virq mapping which it is not responsible of (but instead, the
> function pair mv88e6xxx_g2_irq_setup() + mv88e6xxx_g2_irq_free() is).
> 
> With the current code structure, this isn't such a huge problem, because
> mv88e6xxx_g2_irq_mdio_free() is called relatively close to the real
> owner of the IRQ mappings:
> 
> mv88e6xxx_remove()
> -> mv88e6xxx_unregister_switch()
> -> mv88e6xxx_mdios_unregister()
>     -> mv88e6xxx_g2_irq_mdio_free()
> -> mv88e6xxx_g2_irq_free()
> 
> and the switch isn't 'live' in any way such that it would be able of
> generating interrupts at this point (mv88e6xxx_unregister_switch() has
> been called).
> 
> However, there is a desire to split mv88e6xxx_mdios_unregister() and
> mv88e6xxx_g2_irq_free() such that mv88e6xxx_mdios_unregister() only gets
> called from mv88e6xxx_teardown(). This is much more problematic, as can
> be seen below.
> 
> In a cross-chip scenario (say 3 switches d0032004.mdio-mii:10,
> d0032004.mdio-mii:11 and d0032004.mdio-mii:12 which form a single DSA
> tree), it is possible to unbind the device driver from a single switch
> (say d0032004.mdio-mii:10).
> 
> When that happens, mv88e6xxx_remove() will be called for just that one
> switch, and this will call mv88e6xxx_unregister_switch() which will tear
> down the entire tree (calling mv88e6xxx_teardown() for all 3 switches).
> 
> Assuming mv88e6xxx_mdios_unregister() was moved to mv88e6xxx_teardown(),
> at this stage, all 3 switches will have called irq_dispose_mapping() on
> their mdiobus virqs.
> 
> When we bind again the device driver to d0032004.mdio-mii:10,
> mv88e6xxx_probe() is called for it, which calls dsa_register_switch().
> The DSA tree is now complete again, and mv88e6xxx_setup() is called for
> all 3 switches.
> 
> Also assuming that mv88e6xxx_mdios_register() is moved to
> mv88e6xxx_setup() (the 2 assumptions go together), at this point,
> d0032004.mdio-mii:11 and d0032004.mdio-mii:12 don't have an IRQ mapping
> for the internal PHYs anymore, as they've disposed of it in
> mv88e6xxx_teardown(). Whereas switch d0032004.mdio-mii:10 has re-created
> it, because its code path comes from mv88e6xxx_probe().
> 
> Simply put, this change prepares the driver to handle the movement of
> mv88e6xxx_mdios_register() to mv88e6xxx_setup() for cross-chip DSA trees.
> 
> Also, the code being deleted was partially wrong anyway (in a way which
> may have hidden this other issue). mv88e6xxx_g2_irq_mdio_setup()
> populates bus->irq[] starting with offset chip->info->phy_base_addr, but
> the teardown path doesn't apply that offset too. So it disposes of virq
> 0 for phy = [ 0, phy_base_addr ).
> 
> All switch families have phy_base_addr = 0, except for MV88E6141 and
> MV88E6341 which have it as 0x10. I guess those families would have
> happened to work by mistake in cross-chip scenarios too.
> 
> I'm deleting the body of mv88e6xxx_g2_irq_mdio_free() but leaving its
> call sites and prototype in place. This is because, if we ever need to
> add back some teardown procedure in the future, it will be perhaps
> error-prone to deduce the proper call sites again. Whereas like this,
> no extra code should get generated, it shouldn't bother anybody.
> 
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
> Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH net-next v4 2/4] net: dsa: mv88e6xxx: re-order functions

[Florian Fainelli]

On 3/15/23 09:38, Klaus Kudielka wrote:
> Move mv88e6xxx_setup() below mv88e6xxx_mdios_register(), so that we are
> able to call the latter one from here. Do the same thing for the
> inverse functions.
> 
> Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH net-next v4 3/4] net: dsa: mv88e6xxx: move call to mv88e6xxx_mdios_register()

[Florian Fainelli]

On 3/15/23 09:38, Klaus Kudielka wrote:
> Call the rather expensive mv88e6xxx_mdios_register() at the beginning of
> mv88e6xxx_setup(). This avoids the double call via mv88e6xxx_probe()
> during boot.
> 
> For symmetry, call mv88e6xxx_mdios_unregister() at the end of
> mv88e6xxx_teardown().
> 
> Link: https://lore.kernel.org/lkml/449bde236c08d5ab5e54abd73b645d8b29955894.camel@gmail.com/
> Suggested-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH net-next v4 4/4] net: dsa: mv88e6xxx: mask apparently non-existing phys during probing

[Florian Fainelli]

On 3/15/23 09:38, Klaus Kudielka wrote:
> To avoid excessive mdio bus transactions during probing, mask all phy
> addresses that do not exist (there is a 1:1 mapping between switch port
> number and phy address).
> 
> Suggested-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH net-next v4 0/4] net: dsa: mv88e6xxx: accelerate C45 scan

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net-next.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Wed, 15 Mar 2023 17:38:42 +0100 you wrote:
> 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.
> 
> [...]

Here is the summary with links:
  - [net-next,v4,1/4] net: dsa: mv88e6xxx: don't dispose of Global2 IRQ mappings from mdiobus code
    https://git.kernel.org/netdev/net-next/c/b1a2de9ccfe6
  - [net-next,v4,2/4] net: dsa: mv88e6xxx: re-order functions
    https://git.kernel.org/netdev/net-next/c/f1bee740fa82
  - [net-next,v4,3/4] net: dsa: mv88e6xxx: move call to mv88e6xxx_mdios_register()
    https://git.kernel.org/netdev/net-next/c/2cb0658d4f88
  - [net-next,v4,4/4] net: dsa: mv88e6xxx: mask apparently non-existing phys during probing
    https://git.kernel.org/netdev/net-next/c/2c7e46edbd03

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html

Re: [PATCH net-next v4 4/4] net: dsa: mv88e6xxx: mask apparently non-existing phys during probing

[Marek Behún]

On Wed, 15 Mar 2023 17:38:46 +0100
Klaus Kudielka <klaus.kudielka@gmail.com> wrote:

> To avoid excessive mdio bus transactions during probing, mask all phy
> addresses that do not exist (there is a 1:1 mapping between switch port
> number and phy address).
> 
> Suggested-by: Andrew Lunn <andrew@lunn.ch>
> Signed-off-by: Klaus Kudielka <klaus.kudielka@gmail.com>
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>
> ---
> 
> Notes:
>     v2: Patch is new
> 
>  drivers/net/dsa/mv88e6xxx/chip.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
> index 29b0f3bb1c..c52798d9ce 100644
> --- a/drivers/net/dsa/mv88e6xxx/chip.c
> +++ b/drivers/net/dsa/mv88e6xxx/chip.c
> @@ -3797,6 +3797,7 @@ 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));

shouldnt this be
  GENMASK(31, mv88e6xxx_num_ports(chip) + chip->info->phy_base_addr) |
  GENMASK(chip->info->phy_base_addr, 0)
?
Or alternatively
  ~GENMASK(chip->info->phy_base_addr + mv88e6xxx_num_ports(chip),
           chip->info->phy_base_addr)

Marek

Re: [PATCH net-next v4 4/4] net: dsa: mv88e6xxx: mask apparently non-existing phys during probing

[Vladimir Oltean]

On Sun, Mar 19, 2023 at 11:06:06AM +0100, Marek Behún wrote:
> > +	bus->phy_mask = GENMASK(31, mv88e6xxx_num_ports(chip));
> 
> shouldnt this be
>   GENMASK(31, mv88e6xxx_num_ports(chip) + chip->info->phy_base_addr) |
>   GENMASK(chip->info->phy_base_addr, 0)
> ?
> Or alternatively
>   ~GENMASK(chip->info->phy_base_addr + mv88e6xxx_num_ports(chip),
>            chip->info->phy_base_addr)

Good point. Would you mind sending a patch? I prefer the second variant BTW.

Re: [PATCH net-next v4 4/4] net: dsa: mv88e6xxx: mask apparently non-existing phys during probing

[Vladimir Oltean]

On Sun, Mar 19, 2023 at 11:06:06AM +0100, Marek Behún wrote:
>   ~GENMASK(chip->info->phy_base_addr + mv88e6xxx_num_ports(chip),
>            chip->info->phy_base_addr)

But it needs to be ~GENMASK(base + num - 1, base), no?