[PATCH net v3] net: ngbe: Fix phy mode set to external phy

[PATCH net v3] net: ngbe: Fix phy mode set to external phy

[Mengyuan Lou]

The MAC only has add the TX delay and it can not be modified.
MAC and PHY are both set the TX delay cause transmission problems.
So just disable TX delay in PHY, when use rgmii to attach to
external phy, set PHY_INTERFACE_MODE_RGMII_RXID to phy drivers.
And it is does not matter to internal phy.

Fixes: bc2426d74aa3 ("net: ngbe: convert phylib to phylink")
Signed-off-by: Mengyuan Lou <mengyuanlou@net-swift.com>
Cc: stable@vger.kernel.org # 6.3+
---
v3:
-Rebase the fix commit for net.
v2:
-Add a comment for the code modification.
-Add the problem in commit messages.
https://lore.kernel.org/netdev/E9C427FDDCF0CBC3+20240812103025.42417-1-mengyuanlou@net-swift.com/
v1:
https://lore.kernel.org/netdev/C1587837D62D1BC0+20240806082520.29193-1-mengyuanlou@net-swift.com/

 drivers/net/ethernet/wangxun/ngbe/ngbe_mdio.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/wangxun/ngbe/ngbe_mdio.c b/drivers/net/ethernet/wangxun/ngbe/ngbe_mdio.c
index ec54b18c5fe7..a5e9b779c44d 100644
--- a/drivers/net/ethernet/wangxun/ngbe/ngbe_mdio.c
+++ b/drivers/net/ethernet/wangxun/ngbe/ngbe_mdio.c
@@ -124,8 +124,12 @@ static int ngbe_phylink_init(struct wx *wx)
 				   MAC_SYM_PAUSE | MAC_ASYM_PAUSE;
 	config->mac_managed_pm = true;
 
-	phy_mode = PHY_INTERFACE_MODE_RGMII_ID;
-	__set_bit(PHY_INTERFACE_MODE_RGMII_ID, config->supported_interfaces);
+	/* The MAC only has add the Tx delay and it can not be modified.
+	 * So just disable TX delay in PHY, and it is does not matter to
+	 * internal phy.
+	 */
+	phy_mode = PHY_INTERFACE_MODE_RGMII_RXID;
+	__set_bit(PHY_INTERFACE_MODE_RGMII_RXID, config->supported_interfaces);
 
 	phylink = phylink_create(config, NULL, phy_mode, &ngbe_mac_ops);
 	if (IS_ERR(phylink))
-- 
2.43.2

Re: [PATCH net v3] net: ngbe: Fix phy mode set to external phy

[Jacob Keller]

On 8/19/2024 8:04 PM, Mengyuan Lou wrote:
> The MAC only has add the TX delay and it can not be modified.
> MAC and PHY are both set the TX delay cause transmission problems.
> So just disable TX delay in PHY, when use rgmii to attach to
> external phy, set PHY_INTERFACE_MODE_RGMII_RXID to phy drivers.
> And it is does not matter to internal phy.
> 
> Fixes: bc2426d74aa3 ("net: ngbe: convert phylib to phylink")
> Signed-off-by: Mengyuan Lou <mengyuanlou@net-swift.com>
> Cc: stable@vger.kernel.org # 6.3+
> ---
> v3:
> -Rebase the fix commit for net.
> v2:
> -Add a comment for the code modification.
> -Add the problem in commit messages.
> https://lore.kernel.org/netdev/E9C427FDDCF0CBC3+20240812103025.42417-1-mengyuanlou@net-swift.com/
> v1:
> https://lore.kernel.org/netdev/C1587837D62D1BC0+20240806082520.29193-1-mengyuanlou@net-swift.com/
> 
>  drivers/net/ethernet/wangxun/ngbe/ngbe_mdio.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/wangxun/ngbe/ngbe_mdio.c b/drivers/net/ethernet/wangxun/ngbe/ngbe_mdio.c
> index ec54b18c5fe7..a5e9b779c44d 100644
> --- a/drivers/net/ethernet/wangxun/ngbe/ngbe_mdio.c
> +++ b/drivers/net/ethernet/wangxun/ngbe/ngbe_mdio.c
> @@ -124,8 +124,12 @@ static int ngbe_phylink_init(struct wx *wx)
>  				   MAC_SYM_PAUSE | MAC_ASYM_PAUSE;
>  	config->mac_managed_pm = true;
>  
> -	phy_mode = PHY_INTERFACE_MODE_RGMII_ID;
> -	__set_bit(PHY_INTERFACE_MODE_RGMII_ID, config->supported_interfaces);
> +	/* The MAC only has add the Tx delay and it can not be modified.
> +	 * So just disable TX delay in PHY, and it is does not matter to
> +	 * internal phy.
> +	 */

The language of the comment seems a bit weird to me. It makes more sense
if it read "as it does not matter to the internal PHY".

That being said, its a bit of a nit. With our without changing the comment:

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>

> +	phy_mode = PHY_INTERFACE_MODE_RGMII_RXID;
> +	__set_bit(PHY_INTERFACE_MODE_RGMII_RXID, config->supported_interfaces);
>  
>  	phylink = phylink_create(config, NULL, phy_mode, &ngbe_mac_ops);
>  	if (IS_ERR(phylink))

Re: [PATCH net v3] net: ngbe: Fix phy mode set to external phy

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net.git (main)
by Paolo Abeni <pabeni@redhat.com>:

On Tue, 20 Aug 2024 11:04:25 +0800 you wrote:
> The MAC only has add the TX delay and it can not be modified.
> MAC and PHY are both set the TX delay cause transmission problems.
> So just disable TX delay in PHY, when use rgmii to attach to
> external phy, set PHY_INTERFACE_MODE_RGMII_RXID to phy drivers.
> And it is does not matter to internal phy.
> 
> Fixes: bc2426d74aa3 ("net: ngbe: convert phylib to phylink")
> Signed-off-by: Mengyuan Lou <mengyuanlou@net-swift.com>
> Cc: stable@vger.kernel.org # 6.3+
> 
> [...]

Here is the summary with links:
  - [net,v3] net: ngbe: Fix phy mode set to external phy
    https://git.kernel.org/netdev/net/c/f2916c83d746

You are awesome, thank you!
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