diff mbox series

[net-next,4/4] net: dsa: mv88e6xxx: improve 88e6352 serdes statistics detection

Message ID E1nFcCK-006WN0-Do@rmk-PC.armlinux.org.uk (mailing list archive)
State Accepted
Commit 7f7d32bc2608075bba1055b0c8dcd8499643a814
Delegated to: Netdev Maintainers
Headers show
Series net: dsa: mv88e6xxx: convert to phylink_generic_validate() | expand

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netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers success CCed 7 of 7 maintainers
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
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netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 83 lines checked
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netdev/source_inline success Was 0 now: 0

Commit Message

Russell King (Oracle) Feb. 3, 2022, 1:30 p.m. UTC 
The decision whether to report serdes statistics currently depends on
the cached C_Mode value for the port, read at probe time or updated by
configuration. However, port 4 can be in "automedia" mode when it is
used as a serdes port, meaning it switches between the internal PHY and
the serdes, changing the read-only C_Mode value depending on which
first gains link. Consequently, the C_Mode value read at probe does not
accurately reflect whether the port has the serdes associated with it.

In "net: dsa: mv88e6xxx: add mv88e6352_g2_scratch_port_has_serdes()",
we added a way to read the hardware configuration to determine which
port has the serdes associated with it. Use this to determine which
port reports the serdes statistics.

Reviewed-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
 drivers/net/dsa/mv88e6xxx/serdes.c | 43 ++++++++++++++++--------------
 1 file changed, 23 insertions(+), 20 deletions(-)

Comments

Andrew Lunn Feb. 3, 2022, 1:53 p.m. UTC | #1 
On Thu, Feb 03, 2022 at 01:30:52PM +0000, Russell King (Oracle) wrote:
> The decision whether to report serdes statistics currently depends on
> the cached C_Mode value for the port, read at probe time or updated by
> configuration. However, port 4 can be in "automedia" mode when it is
> used as a serdes port, meaning it switches between the internal PHY and
> the serdes, changing the read-only C_Mode value depending on which
> first gains link. Consequently, the C_Mode value read at probe does not
> accurately reflect whether the port has the serdes associated with it.
> 
> In "net: dsa: mv88e6xxx: add mv88e6352_g2_scratch_port_has_serdes()",
> we added a way to read the hardware configuration to determine which
> port has the serdes associated with it. Use this to determine which
> port reports the serdes statistics.
> 
> Reviewed-by: Marek Behún <kabel@kernel.org>
> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew
diff mbox series

Patch

diff --git a/drivers/net/dsa/mv88e6xxx/serdes.c b/drivers/net/dsa/mv88e6xxx/serdes.c
index 2b05ead515cd..6a177bf654ee 100644
--- a/drivers/net/dsa/mv88e6xxx/serdes.c
+++ b/drivers/net/dsa/mv88e6xxx/serdes.c
@@ -272,14 +272,6 @@  int mv88e6352_serdes_get_lane(struct mv88e6xxx_chip *chip, int port)
 	return lane;
 }
 
-static bool mv88e6352_port_has_serdes(struct mv88e6xxx_chip *chip, int port)
-{
-	if (mv88e6xxx_serdes_get_lane(chip, port) >= 0)
-		return true;
-
-	return false;
-}
-
 struct mv88e6352_serdes_hw_stat {
 	char string[ETH_GSTRING_LEN];
 	int sizeof_stat;
@@ -293,20 +285,24 @@  static struct mv88e6352_serdes_hw_stat mv88e6352_serdes_hw_stats[] = {
 
 int mv88e6352_serdes_get_sset_count(struct mv88e6xxx_chip *chip, int port)
 {
-	if (mv88e6352_port_has_serdes(chip, port))
-		return ARRAY_SIZE(mv88e6352_serdes_hw_stats);
+	int err;
 
-	return 0;
+	err = mv88e6352_g2_scratch_port_has_serdes(chip, port);
+	if (err <= 0)
+		return err;
+
+	return ARRAY_SIZE(mv88e6352_serdes_hw_stats);
 }
 
 int mv88e6352_serdes_get_strings(struct mv88e6xxx_chip *chip,
 				 int port, uint8_t *data)
 {
 	struct mv88e6352_serdes_hw_stat *stat;
-	int i;
+	int err, i;
 
-	if (!mv88e6352_port_has_serdes(chip, port))
-		return 0;
+	err = mv88e6352_g2_scratch_port_has_serdes(chip, port);
+	if (err <= 0)
+		return err;
 
 	for (i = 0; i < ARRAY_SIZE(mv88e6352_serdes_hw_stats); i++) {
 		stat = &mv88e6352_serdes_hw_stats[i];
@@ -348,11 +344,12 @@  int mv88e6352_serdes_get_stats(struct mv88e6xxx_chip *chip, int port,
 {
 	struct mv88e6xxx_port *mv88e6xxx_port = &chip->ports[port];
 	struct mv88e6352_serdes_hw_stat *stat;
+	int i, err;
 	u64 value;
-	int i;
 
-	if (!mv88e6352_port_has_serdes(chip, port))
-		return 0;
+	err = mv88e6352_g2_scratch_port_has_serdes(chip, port);
+	if (err <= 0)
+		return err;
 
 	BUILD_BUG_ON(ARRAY_SIZE(mv88e6352_serdes_hw_stats) >
 		     ARRAY_SIZE(mv88e6xxx_port->serdes_stats));
@@ -419,8 +416,13 @@  unsigned int mv88e6352_serdes_irq_mapping(struct mv88e6xxx_chip *chip, int port)
 
 int mv88e6352_serdes_get_regs_len(struct mv88e6xxx_chip *chip, int port)
 {
-	if (!mv88e6352_port_has_serdes(chip, port))
-		return 0;
+	int err;
+
+	mv88e6xxx_reg_lock(chip);
+	err = mv88e6352_g2_scratch_port_has_serdes(chip, port);
+	mv88e6xxx_reg_unlock(chip);
+	if (err <= 0)
+		return err;
 
 	return 32 * sizeof(u16);
 }
@@ -432,7 +434,8 @@  void mv88e6352_serdes_get_regs(struct mv88e6xxx_chip *chip, int port, void *_p)
 	int err;
 	int i;
 
-	if (!mv88e6352_port_has_serdes(chip, port))
+	err = mv88e6352_g2_scratch_port_has_serdes(chip, port);
+	if (err <= 0)
 		return;
 
 	for (i = 0 ; i < 32; i++) {