On 11.06.2023 10:23, Arınç ÜNAL wrote:

On 10.06.2023 20:55, Vladimir Oltean wrote:

quoted

On Sat, Jun 10, 2023 at 01:57:27PM +0300, Arınç ÜNAL wrote:

quoted

I was able to confirm all user ports of the MT7531BE switch transmit/receive
traffic to/from the SGMII CPU port and computer fine after getting rid of
priv->info->cpu_port_config().

Tried all user ports being affine to the RGMII CPU port, that works too.

https://github.com/arinc9/linux/commit/4e79313a95d45950cab526456ef0030286ba4d4e

Did you do black-box testing after removing the code, or were you
also able to independently confirm that the configurations done by
cpu_port_config() were later overwritten? I'm trying to disambiguate
between "works by coincidence" and "works because the analysis was
correct".

I did my testing, merely to make sure we didn't miss anything as Russell already stated that the configuration from cpu_port_config() is later overwritten.

I could put some dev_info around to confirm the code path that overwrites the configuration.

I have finally tested this.

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index a4468468b53c..7b60a67d016a 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c

@@ -968,9 +968,11 @@ mt753x_cpu_port_enable(struct dsa_switch *ds, int port)
  
  	/* Setup max capability of CPU port at first */
  	if (priv->info->cpu_port_config) {
+		dev_info(priv->dev, "running cpu_port_config()\n");
  		ret = priv->info->cpu_port_config(ds, port);
  		if (ret)
  			return ret;
+		dev_info(priv->dev, "cpu_port_config() ran\n");
  	}
  
  	/* Enable Mediatek header mode on the cpu port */

@@ -1024,6 +1026,9 @@ mt7530_port_enable(struct dsa_switch *ds, int port,
  		   priv->ports[port].pm);
  	mt7530_clear(priv, MT7530_PMCR_P(port), PMCR_LINK_SETTINGS_MASK);
  
+	if ((port == 5 || port == 6) && dsa_port_is_cpu(dp))
+		dev_info(priv->dev, "MT7530_PMCR_P%d PMCR_LINK_SETTINGS_MASK is cleared\n", port);
+
  	mutex_unlock(&priv->reg_mutex);
  
  	return 0;

@@ -2693,6 +2698,9 @@ mt753x_phylink_mac_config(struct dsa_switch *ds, int port, unsigned int mode,
  	mcr_new |= PMCR_IFG_XMIT(1) | PMCR_MAC_MODE | PMCR_BACKOFF_EN |
  		   PMCR_BACKPR_EN | PMCR_FORCE_MODE_ID(priv->id);
  
+	if ((port == 5 && dsa_is_cpu_port(ds, 5)) || (port == 6 && dsa_is_cpu_port(ds, 6)))
+		dev_info(priv->dev, "MT7530_PMCR_P%d PMCR_CPU_PORT_SETTING equivalent is set\n", port);
+
  	/* Are we connected to external phy */
  	if (port == 5 && dsa_is_user_port(ds, 5))
  		mcr_new |= PMCR_EXT_PHY;

@@ -2760,6 +2768,9 @@ static void mt753x_phylink_mac_link_up(struct dsa_switch *ds, int port,
  	}
  
  	mt7530_set(priv, MT7530_PMCR_P(port), mcr);
+
+	if ((port == 5 && dsa_is_cpu_port(ds, 5)) || (port == 6 && dsa_is_cpu_port(ds, 6)))
+		dev_info(priv->dev, "MT7530_PMCR_P%d PMCR_LINK_SETTINGS_MASK equivalent is set\n", port);
  }
  
  static int

@@ -2796,6 +2807,9 @@ mt7531_cpu_port_config(struct dsa_switch *ds, int port)
  
  	mt7530_write(priv, MT7530_PMCR_P(port),
  		     PMCR_CPU_PORT_SETTING(priv->id));
+
+	dev_info(priv->dev, "MT7530_PMCR_P%d PMCR_CPU_PORT_SETTING is set\n", port);
+
  	mt753x_phylink_mac_link_up(ds, port, MLO_AN_FIXED, interface, NULL,
  				   speed, DUPLEX_FULL, true, true);
  

[    1.763066] mt7530-mdio mdio-bus:00: running cpu_port_config()
[    1.769237] mt7530-mdio mdio-bus:00: MT7530_PMCR_P5 PMCR_CPU_PORT_SETTING is set
[    1.776724] mt7530-mdio mdio-bus:00: MT7530_PMCR_P5 PMCR_LINK_SETTINGS_MASK equivalent is set
[    1.785254] mt7530-mdio mdio-bus:00: cpu_port_config() ran
[    1.792098] mt7530-mdio mdio-bus:00: running cpu_port_config()
[    1.798019] mt7530-mdio mdio-bus:00: MT7530_PMCR_P6 PMCR_CPU_PORT_SETTING is set
[    1.805502] mt7530-mdio mdio-bus:00: MT7530_PMCR_P6 PMCR_LINK_SETTINGS_MASK equivalent is set
[    1.814023] mt7530-mdio mdio-bus:00: cpu_port_config() ran
[    1.844941] mt7530-mdio mdio-bus:00: MT7530_PMCR_P5 PMCR_LINK_SETTINGS_MASK is cleared
[    1.852972] mt7530-mdio mdio-bus:00: configuring for fixed/rgmii link mode
[    1.859944] mt7530-mdio mdio-bus:00: MT7530_PMCR_P5 PMCR_CPU_PORT_SETTING equivalent is set
[    1.868658] mt7530-mdio mdio-bus:00: MT7530_PMCR_P5 PMCR_LINK_SETTINGS_MASK equivalent is set
[    1.868913] mt7530-mdio mdio-bus:00: MT7530_PMCR_P6 PMCR_LINK_SETTINGS_MASK is cleared
[    1.877190] mt7530-mdio mdio-bus:00: Link is Up - 1Gbps/Full - flow control rx/tx
[    1.885179] mt7530-mdio mdio-bus:00: configuring for fixed/2500base-x link mode
[    1.899973] mt7530-mdio mdio-bus:00: MT7530_PMCR_P6 PMCR_CPU_PORT_SETTING equivalent is set
[    1.910147] mt7530-mdio mdio-bus:00: MT7530_PMCR_P6 PMCR_LINK_SETTINGS_MASK equivalent is set
[    1.918681] mt7530-mdio mdio-bus:00: Link is Up - 2.5Gbps/Full - flow control rx/tx
[    1.920654] mt7530-mdio mdio-bus:00 wan (uninitialized): PHY [mt7530-0:00] driver [MediaTek MT7531 PHY] (irq=137)
[    1.948453] mt7530-mdio mdio-bus:00 lan0 (uninitialized): PHY [mt7530-0:01] driver [MediaTek MT7531 PHY] (irq=138)
[    1.970382] mt7530-mdio mdio-bus:00 lan1 (uninitialized): PHY [mt7530-0:02] driver [MediaTek MT7531 PHY] (irq=139)
[    1.992423] mt7530-mdio mdio-bus:00 lan2 (uninitialized): PHY [mt7530-0:03] driver [MediaTek MT7531 PHY] (irq=140)
[    2.014310] mt7530-mdio mdio-bus:00 lan3 (uninitialized): PHY [mt7530-0:04] driver [MediaTek MT7531 PHY] (irq=141)
[    2.025396] mtk_soc_eth 1b100000.ethernet eth1: entered promiscuous mode
[    2.032160] mtk_soc_eth 1b100000.ethernet eth0: entered promiscuous mode
[    2.038912] DSA: tree 0 setup

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