Re: [PATCH v5 8/8] net: stmmac: qcom-ethqos: add support for sa8255p

On Tue, Nov 11, 2025 at 12:48 PM Simon Horman <[email protected]> wrote:
>
> On Fri, Nov 07, 2025 at 11:29:58AM +0100, Bartosz Golaszewski wrote:
> > From: Bartosz Golaszewski <[email protected]>
>
> ...
>
> > +static int qcom_ethqos_pd_init(struct platform_device *pdev, void *priv)
> > +{
> > +     struct qcom_ethqos *ethqos = priv;
> > +     int ret;
> > +
> > +     /*
> > +      * Enable functional clock to prevent DMA reset after timeout due
> > +      * to no PHY clock being enabled after the hardware block has been
> > +      * power cycled. The actual configuration will be adjusted once
> > +      * ethqos_fix_mac_speed() is called.
> > +      */
> > +     ethqos_set_func_clk_en(ethqos);
> > +
> > +     ret = qcom_ethqos_domain_on(ethqos, ETHQOS_PD_CORE);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = qcom_ethqos_domain_on(ethqos, ETHQOS_PD_MDIO);
> > +     if (ret) {
> > +             qcom_ethqos_domain_off(ethqos, ETHQOS_PD_CORE);
> > +             return ret;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static void qcom_ethqos_pd_exit(struct platform_device *pdev, void *data)
> > +{
> > +     struct qcom_ethqos *ethqos = data;
> > +
> > +     qcom_ethqos_domain_off(ethqos, ETHQOS_PD_MDIO);
> > +     qcom_ethqos_domain_off(ethqos, ETHQOS_PD_CORE);
> > +}
> > +
> >  static void ethqos_ptp_clk_freq_config(struct stmmac_priv *priv)
> >  {
> >       struct plat_stmmacenet_data *plat_dat = priv->plat;
>
> ...
>
> > @@ -852,28 +993,63 @@ static int qcom_ethqos_probe(struct platform_device *pdev)
> >       ethqos->rgmii_config_loopback_en = drv_data->rgmii_config_loopback_en;
> >       ethqos->has_emac_ge_3 = drv_data->has_emac_ge_3;
> >       ethqos->needs_sgmii_loopback = drv_data->needs_sgmii_loopback;
> > -
> > -     ethqos->pm.link_clk = devm_clk_get(dev, clk_name);
> > -     if (IS_ERR(ethqos->pm.link_clk))
> > -             return dev_err_probe(dev, PTR_ERR(ethqos->pm.link_clk),
> > -                                  "Failed to get link_clk\n");
> > -
> > -     ret = ethqos_clks_config(ethqos, true);
> > -     if (ret)
> > -             return ret;
> > -
> > -     ret = devm_add_action_or_reset(dev, ethqos_clks_disable, ethqos);
> > -     if (ret)
> > -             return ret;
> > -
> > -     ethqos->pm.serdes_phy = devm_phy_optional_get(dev, "serdes");
> > -     if (IS_ERR(ethqos->pm.serdes_phy))
> > -             return dev_err_probe(dev, PTR_ERR(ethqos->pm.serdes_phy),
> > -                                  "Failed to get serdes phy\n");
> > -
> > -     ethqos->set_serdes_speed = ethqos_set_serdes_speed_phy;
> >       ethqos->serdes_speed = SPEED_1000;
> > -     ethqos_update_link_clk(ethqos, SPEED_1000);
> > +
> > +     if (pm_data && pm_data->use_domains) {
> > +             ethqos->set_serdes_speed = ethqos_set_serdes_speed_pd;
> > +
> > +             ret = devm_pm_domain_attach_list(dev, &pm_data->pd,
> > +                                              &ethqos->pd.pd_list);
> > +             if (ret < 0)
> > +                     return dev_err_probe(dev, ret, "Failed to attach power domains\n");
> > +
> > +             plat_dat->clks_config = ethqos_pd_clks_config;
> > +             plat_dat->serdes_powerup = qcom_ethqos_pd_serdes_powerup;
> > +             plat_dat->serdes_powerdown = qcom_ethqos_pd_serdes_powerdown;
> > +             plat_dat->exit = qcom_ethqos_pd_exit;
>
> Hi Bartosz,
>
> It seems that the intention of this is to ensure
> that domains turned on by qcom_ethqos_pd_init()
> are turned off again on exit or clean-up in error paths.
>
> > +             plat_dat->init = qcom_ethqos_pd_init;
> > +             plat_dat->clk_ptp_rate = pm_data->clk_ptp_rate;
> > +
> > +             ret = qcom_ethqos_pd_init(pdev, ethqos);
> > +             if (ret)
> > +                     return ret;
>
> And here those domains are turned on.
>
> > +
> > +             ret = qcom_ethqos_domain_on(ethqos, ETHQOS_PD_SERDES);
> > +             if (ret)
>
> But it seems that if we reach this error path then the cleanup is not
> performed. This is because plat_dat and thus it's exit callback are
> registered until the call to devm_stmmac_pltfr_probe() towards the end of
> this function.

We can only reach this if devm_stmmac_pltfr_probe() fails. Yeah it
probably warrants a devres action.

Bartosz