Re: [PATCH net-next v3 3/6] net: hisilicon: add support for hisi_femac core on Hi3798MV200

[Yang Xiwen]

On 2/20/2024 10:47 PM, Maxime Chevallier wrote:
> Hello,
>
> On Tue, 20 Feb 2024 03:57:38 +0800
> Yang Xiwen via B4 Relay <devnull+forbidden405.outlook.com@xxxxxxxxxx>
> wrote:
>
> > From: Yang Xiwen <forbidden405@xxxxxxxxxxx>
> >
> > Register the sub MDIO bus if it is found. Also implement the internal
> > PHY reset procedure as needed.
> >
> > Note it's unable to put the MDIO bus node outside of MAC controller
> > (i.e. at the same level in the parent bus node). Because we need to
> > control all clocks and resets in FEMAC driver due to the phy reset
> > procedure. So the clocks can't be assigned to MDIO bus device, which is
> > an essential resource for the MDIO bus to work.
> >
> > No backward compatibility is maintained since the only existing
> > user(Hi3516DV300) has not received any updates from HiSilicon for about
> > 8 years already. And till today, no mainline dts for this SoC is found.
> > It seems unlikely that there are still existing mainline Hi3516DV300
> > users. The effort to maintain the old binding seems gain a little.
> >
> > Signed-off-by: Yang Xiwen <forbidden405@xxxxxxxxxxx>
> Besides what Andrew and Simon already mentionned, I have a few other
> small comments :
>
> [...]
>
> > @@ -797,23 +816,22 @@ static int hisi_femac_drv_probe(struct platform_device *pdev)
> >   		goto out_free_netdev;
> >   	}
> >   
> > -	priv->clk = devm_clk_get(&pdev->dev, NULL);
> > -	if (IS_ERR(priv->clk)) {
> > -		dev_err(dev, "failed to get clk\n");
> > -		ret = -ENODEV;
> > +	ret = devm_clk_bulk_get_all(&pdev->dev, &priv->clks);
> > +	if (ret < 0 || ret != CLK_NUM) {
> > +		dev_err(dev, "failed to get clk bulk: %d\n", ret);
> >   		goto out_free_netdev;
> >   	}
> >   
> > -	ret = clk_prepare_enable(priv->clk);
> > +	ret = clk_bulk_prepare_enable(CLK_NUM, priv->clks);
> >   	if (ret) {
> > -		dev_err(dev, "failed to enable clk %d\n", ret);
> > +		dev_err(dev, "failed to enable clk bulk: %d\n", ret);
> >   		goto out_free_netdev;
> >   	}
> >   
> >   	priv->mac_rst = devm_reset_control_get(dev, "mac");
> >   	if (IS_ERR(priv->mac_rst)) {
> >   		ret = PTR_ERR(priv->mac_rst);
> > -		goto out_disable_clk;
> > +		goto out_free_netdev;
> When you return here (or even later), you are missing a call to
> "clk_bulk_disable_unprepare" in the cleanup path


I didn't notice that. Originally i'm using devm_clk_get_enabled() so 
it's not needed.


Maybe we can add a devm_clk_bulk_get_prepared_enabled() API to clk 
framework too.


> >   	}
> >   	hisi_femac_core_reset(priv);
> >   
> > @@ -826,15 +844,34 @@ static int hisi_femac_drv_probe(struct platform_device *pdev)
> >   						 priv->phy_reset_delays,
> >   						 DELAYS_NUM);
> >   		if (ret)
> > -			goto out_disable_clk;
> > +			goto out_free_netdev;
> >   		hisi_femac_phy_reset(priv);
> >   	}
> >   
> > +	// Register the optional MDIO bus
> I think this comment style should be avoided, in favor of C-style
> comments ( /* blabla */ )


Will fix in next release.


> > +	for_each_available_child_of_node(node, mdio_np) {
> > +		if (of_node_name_prefix(mdio_np, "mdio")) {
> > +			priv->mdio_pdev = of_platform_device_create(mdio_np, NULL, dev);
> > +			of_node_put(mdio_np);
> > +			if (!priv->mdio_pdev) {
> > +				dev_err(dev, "failed to register MDIO bus device\n");
> > +				ret = -ENODEV;
> > +				goto out_free_netdev;
> > +			}
> > +			mdio_registered = true;
> > +			break;
> > +		}
> > +		of_node_put(mdio_np);
> > +	}
> > +
> > +	if (!mdio_registered)
> > +		dev_warn(dev, "MDIO subnode not found. This is usually a bug.\n");
> > +
> >   	phy = of_phy_get_and_connect(ndev, node, hisi_femac_adjust_link);
> >   	if (!phy) {
> >   		dev_err(dev, "connect to PHY failed!\n");
> >   		ret = -ENODEV;
> > -		goto out_disable_clk;
> > +		goto out_unregister_mdio_bus;
> >   	}
> >   
> >   	phy_attached_print(phy, "phy_id=0x%.8lx, phy_mode=%s\n",
> Thanks,
>
> Maxime


--
Regards,
Yang Xiwen