[PATCH v4 2/2] ethernet: eswin: Add eic7700 ethernet driver

[李志]

Dear Russell King,

In last week’s reply, we addressed two questions.
The main question now is whether it makes sense to use
devm_clk_bulk_get_optional() in the next patch.

Could you please share your thoughts or specific suggestions on this?
Thanks for your time and guidance.

Li Zhi
Eswin Computing


> -----原始邮件-----
> 发件人: "Russell King (Oracle)" <linux at armlinux.org.uk>
> 发送时间:2025-08-27 16:24:51 (星期三)
> 收件人: weishangjuan at eswincomputing.com
> 抄送: devicetree at vger.kernel.org, andrew+netdev at lunn.ch, davem at davemloft.net, edumazet at google.com, kuba at kernel.org, pabeni at redhat.com, robh at kernel.org, krzk+dt at kernel.org, conor+dt at kernel.org, linux-arm-kernel at lists.infradead.org, mcoquelin.stm32 at gmail.com, alexandre.torgue at foss.st.com, yong.liang.choong at linux.intel.com, vladimir.oltean at nxp.com, faizal.abdul.rahim at linux.intel.com, prabhakar.mahadev-lad.rj at bp.renesas.com, inochiama at gmail.com, jan.petrous at oss.nxp.com, jszhang at kernel.org, p.zabel at pengutronix.de, boon.khai.ng at altera.com, 0x1207 at gmail.com, netdev at vger.kernel.org, linux-kernel at vger.kernel.org, linux-stm32 at st-md-mailman.stormreply.com, ningyu at eswincomputing.com, linmin at eswincomputing.com, lizhi2 at eswincomputing.com
> 主题: Re: [PATCH v4 2/2] ethernet: eswin: Add eic7700 ethernet driver
> 
> On Wed, Aug 27, 2025 at 04:14:17PM +0800, weishangjuan at eswincomputing.com wrote:
> > +struct eic7700_qos_priv {
> > +	struct device *dev;
> > +	struct regmap *hsp_regmap;
> > +	struct clk *clk_tx;
> 
> Consider putting a pointer to the plat_dat here instead of clk_tx.
> 
> > +	struct clk *clk_axi;
> > +	struct clk *clk_cfg;
> 
> Consider moving these into plat_dat->clks.
> 
> > +	u32 tx_delay_ps;
> > +	u32 rx_delay_ps;
> > +};
> > +
> > +/**
> > + * eic7700_apply_delay - Update TX or RX delay bits in delay parameter value.
> > + * @delay_ps: Delay in picoseconds (capped at 12.7ns).
> > + * @reg:      Pointer to register value to modify.
> > + * @is_rx:    True for RX delay (bits 30:24), false for TX delay (bits 14:8).
> > + *
> > + * Converts delay to 0.1ns units, caps at 0x7F, and sets appropriate bits.
> > + * Only RX or TX bits are updated; other bits remain unchanged.
> > + */
> > +static inline void eic7700_apply_delay(u32 delay_ps, u32 *reg, bool is_rx)
> > +{
> > +	if (!reg)
> > +		return;
> > +
> > +	u32 val = min(delay_ps / 100, EIC7700_MAX_DELAY_UNIT);
> > +
> > +	if (is_rx) {
> > +		*reg &= ~EIC7700_ETH_RX_ADJ_DELAY;
> > +		*reg |= (val << 24) & EIC7700_ETH_RX_ADJ_DELAY;
> > +	} else {
> > +		*reg &= ~EIC7700_ETH_TX_ADJ_DELAY;
> > +		*reg |= (val << 8) & EIC7700_ETH_TX_ADJ_DELAY;
> > +	}
> > +}
> > +
> > +static int eic7700_clks_config(void *priv, bool enabled)
> > +{
> > +	struct eic7700_qos_priv *dwc = (struct eic7700_qos_priv *)priv;
> > +	int ret = 0;
> > +
> > +	if (enabled) {
> > +		ret = clk_prepare_enable(dwc->clk_tx);
> > +		if (ret < 0) {
> > +			dev_err(dwc->dev, "Failed to enable tx clock: %d\n",
> > +				ret);
> > +			goto err;
> > +		}
> > +
> > +		ret = clk_prepare_enable(dwc->clk_axi);
> > +		if (ret < 0) {
> > +			dev_err(dwc->dev, "Failed to enable axi clock: %d\n",
> > +				ret);
> > +			goto err_tx;
> > +		}
> > +
> > +		ret = clk_prepare_enable(dwc->clk_cfg);
> > +		if (ret < 0) {
> > +			dev_err(dwc->dev, "Failed to enable cfg clock: %d\n",
> > +				ret);
> > +			goto err_axi;
> > +		}
> 
> You can then use clk_bulk_prepare_enable() here without the complex
> unwinding if one enable fails.
> 
> > +	} else {
> > +		clk_disable_unprepare(dwc->clk_tx);
> > +		clk_disable_unprepare(dwc->clk_axi);
> > +		clk_disable_unprepare(dwc->clk_cfg);
> 
> and clk_bulk_disable_unprepare() here.
> 
> > +	}
> > +	return ret;
> > +
> > +err_axi:
> > +	clk_disable_unprepare(dwc->clk_axi);
> > +err_tx:
> > +	clk_disable_unprepare(dwc->clk_tx);
> > +err:
> > +	return ret;
> > +}
> > +
> > +static int eic7700_dwmac_probe(struct platform_device *pdev)
> > +{
> > +	struct plat_stmmacenet_data *plat_dat;
> > +	struct stmmac_resources stmmac_res;
> > +	struct eic7700_qos_priv *dwc_priv;
> > +	u32 eth_axi_lp_ctrl_offset;
> > +	u32 eth_phy_ctrl_offset;
> > +	u32 eth_phy_ctrl_regset;
> > +	u32 eth_rxd_dly_offset;
> > +	u32 eth_dly_param = 0;
> > +	int ret;
> > +
> > +	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
> > +	if (ret)
> > +		return dev_err_probe(&pdev->dev, ret,
> > +				"failed to get resources\n");
> > +
> > +	plat_dat = devm_stmmac_probe_config_dt(pdev, stmmac_res.mac);
> > +	if (IS_ERR(plat_dat))
> > +		return dev_err_probe(&pdev->dev, PTR_ERR(plat_dat),
> > +				"dt configuration failed\n");
> > +
> > +	dwc_priv = devm_kzalloc(&pdev->dev, sizeof(*dwc_priv), GFP_KERNEL);
> > +	if (!dwc_priv)
> > +		return -ENOMEM;
> > +
> > +	dwc_priv->dev = &pdev->dev;
> > +
> > +	/* Read rx-internal-delay-ps and update rx_clk delay */
> > +	if (!of_property_read_u32(pdev->dev.of_node,
> > +				  "rx-internal-delay-ps",
> > +				  &dwc_priv->rx_delay_ps)) {
> > +		eic7700_apply_delay(dwc_priv->rx_delay_ps,
> > +				    &eth_dly_param, true);
> > +	} else {
> > +		dev_warn(&pdev->dev, "can't get rx-internal-delay-ps\n");
> > +	}
> > +
> > +	/* Read tx-internal-delay-ps and update tx_clk delay */
> > +	if (!of_property_read_u32(pdev->dev.of_node,
> > +				  "tx-internal-delay-ps",
> > +				  &dwc_priv->tx_delay_ps)) {
> > +		eic7700_apply_delay(dwc_priv->tx_delay_ps,
> > +				    &eth_dly_param, false);
> > +	} else {
> > +		dev_warn(&pdev->dev, "can't get tx-internal-delay-ps\n");
> > +	}
> > +
> > +	dwc_priv->hsp_regmap =
> > +		syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
> > +						"eswin,hsp-sp-csr");
> > +	if (IS_ERR(dwc_priv->hsp_regmap))
> > +		return dev_err_probe(&pdev->dev,
> > +				PTR_ERR(dwc_priv->hsp_regmap),
> > +				"Failed to get hsp-sp-csr regmap\n");
> > +
> > +	ret = of_property_read_u32_index(pdev->dev.of_node,
> > +					 "eswin,hsp-sp-csr",
> > +					 1, &eth_phy_ctrl_offset);
> > +	if (ret)
> > +		return dev_err_probe(&pdev->dev,
> > +				ret,
> > +				"can't get eth_phy_ctrl_offset\n");
> > +
> > +	regmap_read(dwc_priv->hsp_regmap, eth_phy_ctrl_offset,
> > +		    &eth_phy_ctrl_regset);
> > +	eth_phy_ctrl_regset |=
> > +		(EIC7700_ETH_TX_CLK_SEL | EIC7700_ETH_PHY_INTF_SELI);
> > +	regmap_write(dwc_priv->hsp_regmap, eth_phy_ctrl_offset,
> > +		     eth_phy_ctrl_regset);
> > +
> > +	ret = of_property_read_u32_index(pdev->dev.of_node,
> > +					 "eswin,hsp-sp-csr",
> > +					 2, &eth_axi_lp_ctrl_offset);
> > +	if (ret)
> > +		return dev_err_probe(&pdev->dev,
> > +				ret,
> > +				"can't get eth_axi_lp_ctrl_offset\n");
> > +
> > +	regmap_write(dwc_priv->hsp_regmap, eth_axi_lp_ctrl_offset,
> > +		     EIC7700_ETH_CSYSREQ_VAL);
> > +
> > +	ret = of_property_read_u32_index(pdev->dev.of_node,
> > +					 "eswin,hsp-sp-csr",
> > +					 3, &eth_rxd_dly_offset);
> > +	if (ret)
> > +		return dev_err_probe(&pdev->dev,
> > +				ret,
> > +				"can't get eth_rxd_dly_offset\n");
> > +
> > +	regmap_write(dwc_priv->hsp_regmap, eth_rxd_dly_offset,
> > +		     eth_dly_param);
> > +
> > +	dwc_priv->clk_tx = devm_clk_get(&pdev->dev, "tx");
> > +	if (IS_ERR(dwc_priv->clk_tx))
> > +		return dev_err_probe(&pdev->dev,
> > +				PTR_ERR(dwc_priv->clk_tx),
> > +				"error getting tx clock\n");
> > +
> > +	dwc_priv->clk_axi = devm_clk_get(&pdev->dev, "axi");
> > +	if (IS_ERR(dwc_priv->clk_axi))
> > +		return dev_err_probe(&pdev->dev,
> > +				PTR_ERR(dwc_priv->clk_axi),
> > +				"error getting axi clock\n");
> > +
> > +	dwc_priv->clk_cfg = devm_clk_get(&pdev->dev, "cfg");
> > +	if (IS_ERR(dwc_priv->clk_cfg))
> > +		return dev_err_probe(&pdev->dev,
> > +				PTR_ERR(dwc_priv->clk_cfg),
> > +				"error getting cfg clock\n");
> 
> These then become devm_clk_bulk_get_all().
> 
> > +
> > +	ret = eic7700_clks_config(dwc_priv, true);
> > +	if (ret)
> > +		return dev_err_probe(&pdev->dev,
> > +				ret,
> > +				"error enable clock\n");
> 
> Maybe even devm_clk_bulk_get_all_enabled() which will omit this
> step...
> 
> > +
> > +	plat_dat->clk_tx_i = dwc_priv->clk_tx;
> > +	plat_dat->set_clk_tx_rate = stmmac_set_clk_tx_rate;
> > +	plat_dat->bsp_priv = dwc_priv;
> > +	plat_dat->clks_config = eic7700_clks_config;
> > +
> > +	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
> > +	if (ret) {
> > +		eic7700_clks_config(dwc_priv, false);
> 
> ... and means you don't need this call...
> 
> > +		return dev_err_probe(&pdev->dev,
> > +				ret,
> > +				"Failed to driver probe\n");
> > +	}
> > +
> > +	return ret;
> > +}
> > +
> > +static void eic7700_dwmac_remove(struct platform_device *pdev)
> > +{
> > +	struct eic7700_qos_priv *dwc_priv = get_stmmac_bsp_priv(&pdev->dev);
> > +
> > +	stmmac_pltfr_remove(pdev);
> > +	eic7700_clks_config(dwc_priv, false);
> > +}
> 
> ... and you can remove this function entirely ...
> 
> > +
> > +static const struct of_device_id eic7700_dwmac_match[] = {
> > +	{ .compatible = "eswin,eic7700-qos-eth" },
> > +	{ }
> > +};
> > +MODULE_DEVICE_TABLE(of, eic7700_dwmac_match);
> > +
> > +static struct platform_driver eic7700_dwmac_driver = {
> > +	.probe  = eic7700_dwmac_probe,
> > +	.remove = eic7700_dwmac_remove,
> 
> ... replacing this with stmmac_pltfr_remove().
> 
> Thanks.
> 
> -- 
> RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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