Re: [net-next v2 4/5] net: stmmac: starfive: Add JHB100 SGMII interface

[Minda Chen]

> 
> > -----Original Message-----
> > From: Minda Chen <minda.chen@xxxxxxxxxxxxxxxx>
> > Sent: Friday, April 17, 2026 8:15 AM
> > To: Alexandre Torgue <alexandre.torgue@xxxxxxxxxxx>; Andrew Lunn
> > <andrew+netdev@xxxxxxx>; David S . Miller <davem@xxxxxxxxxxxxx>; Eric
> > Dumazet <edumazet@xxxxxxxxxx>; Jakub Kicinski <kuba@xxxxxxxxxx>; Paolo
> > Abeni <pabeni@xxxxxxxxxx>; Maxime Coquelin
> > <mcoquelin.stm32@xxxxxxxxx>; Emil Renner Berthing
> > <emil.renner.berthing@xxxxxxxxxxxxx>; Rob Herring
> > <robh+dt@xxxxxxxxxx>; Krzysztof Kozlowski <krzk+dt@xxxxxxxxxx>; Conor
> > Dooley <conor@xxxxxxxxxx>; netdev@xxxxxxxxxxxxxxx
> > Cc: linux-kernel@xxxxxxxxxxxxxxx; linux-stm32@st-md-
> > mailman.stormreply.com; devicetree@xxxxxxxxxxxxxxx; Minda Chen
> > <minda.chen@xxxxxxxxxxxxxxxx>
> > Subject: [net-next v2 4/5] net: stmmac: starfive: Add JHB100 SGMII
> > interface
> >
> > Add JHB100 compatible and SGMII support. JHB100 soc contains 2 SGMII
> > interfaces and integrated with serdes PHY. SGMII with split TX/RX MAC
> > clock and need to set 2. 5M/25M/125M TX/RX clock rate in
> > 10M/100M/1000M speed mode. Signed-off-by:
> > Add JHB100 compatible and SGMII support. JHB100 soc contains
> > 2 SGMII interfaces and integrated with serdes PHY. SGMII with split
> > TX/RX MAC clock and need to set 2.5M/25M/125M TX/RX clock rate in
> > 10M/100M/1000M speed mode.
> >
> > Signed-off-by: Minda Chen <minda.chen@xxxxxxxxxxxxxxxx>
> > ---
> >  .../ethernet/stmicro/stmmac/dwmac-starfive.c  | 54
> > ++++++++++++++-----
> >  1 file changed, 42 insertions(+), 12 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-starfive.c
> > b/drivers/net/ethernet/stmicro/stmmac/dwmac-starfive.c
> > index 16b955a6d77b..91698c763dac 100644
> > --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-starfive.c
> > +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-starfive.c
> > @@ -26,6 +26,7 @@ struct starfive_dwmac_data {  struct starfive_dwmac {
> >  	struct device *dev;
> >  	const struct starfive_dwmac_data *data;
> > +	struct clk *sgmii_rx;
> >  };
> >
> >  static int starfive_dwmac_set_mode(struct plat_stmmacenet_data
> > *plat_dat) @@ -68,6 +69,24 @@ static int
> > starfive_dwmac_set_mode(struct plat_stmmacenet_data *plat_dat)
> >  	return 0;
> >  }
> >
> > +static int stmmac_starfive_sgmii_set_clk_rate(void *bsp_priv, struct
> > +clk
> > *clk_tx_i,
> > +					      phy_interface_t interface, int
> > speed) {
> 
> phy_interface_t interface is likely unused in stmmac_starfive_sgmii_set_clk_rate
> → may need __maybe_unused or (void)interface to avoid
> -Werror=unused-parameter on strict builds.
> 
Okay . Thanks for review!

> > +	struct starfive_dwmac *dwmac = (void *)bsp_priv;
> > +	long rate = rgmii_clock(speed);
> > +	int ret;
> > +
> > +	/* MAC clock rate the same as RGMII */
> > +	if (rate < 0)
> > +		return 0;
> > +
> > +	ret = clk_set_rate(clk_tx_i, rate);
> > +	if (ret)
> > +		return ret;
> > +
> > +	return clk_set_rate(dwmac->sgmii_rx, rate); }
> > +
> >  static int starfive_dwmac_probe(struct platform_device *pdev)  {
> >  	struct plat_stmmacenet_data *plat_dat; @@ -102,24 +121,34 @@ static
> > int starfive_dwmac_probe(struct platform_device *pdev)
> >  		return dev_err_probe(&pdev->dev, PTR_ERR(clk_gtx),
> >  				     "error getting gtx clock\n");
> >
> > -	/* Generally, the rgmii_tx clock is provided by the internal clock,
> > -	 * which needs to match the corresponding clock frequency according
> > -	 * to different speeds. If the rgmii_tx clock is provided by the
> > -	 * external rgmii_rxin, there is no need to configure the clock
> > -	 * internally, because rgmii_rxin will be adaptively adjusted.
> > -	 */
> > -	if (!device_property_read_bool(&pdev->dev, "starfive,tx-use-rgmii-
> > clk"))
> > -		plat_dat->set_clk_tx_rate = stmmac_set_clk_tx_rate;
> > +	if (plat_dat->phy_interface == PHY_INTERFACE_MODE_SGMII) {
> > +		dwmac->sgmii_rx = devm_clk_get_enabled(&pdev->dev,
> > "sgmii_rx");
> > +		if (IS_ERR(dwmac->sgmii_rx))
> > +			return dev_err_probe(&pdev->dev,
> > +					     PTR_ERR(dwmac->sgmii_rx),
> > +					     "error getting sgmii rx clock\n");
> > +		plat_dat->set_clk_tx_rate =
> > stmmac_starfive_sgmii_set_clk_rate;
> > +	} else {
> > +		/*
> > +		 * Generally, the rgmii_tx clock is provided by the internal
> > clock,
> > +		 * which needs to match the corresponding clock frequency
> > according
> > +		 * to different speeds. If the rgmii_tx clock is provided by the
> > +		 * external rgmii_rxin, there is no need to configure the clock
> > +		 * internally, because rgmii_rxin will be adaptively adjusted.
> > +		 */
> > +		if (!device_property_read_bool(&pdev->dev, "starfive,tx-use-
> > rgmii-clk"))
> > +			plat_dat->set_clk_tx_rate = stmmac_set_clk_tx_rate;
> > +
> > +		err = starfive_dwmac_set_mode(plat_dat);
> > +		if (err)
> > +			return err;
> > +	}
> >
> >  	dwmac->dev = &pdev->dev;
> >  	plat_dat->flags |= STMMAC_FLAG_EN_TX_LPI_CLK_PHY_CAP;
> >  	plat_dat->bsp_priv = dwmac;
> >  	plat_dat->dma_cfg->dche = true;
> >
> > -	err = starfive_dwmac_set_mode(plat_dat);
> > -	if (err)
> > -		return err;
> > -
> >  	return stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);  }
> >
> > @@ -130,6 +159,7 @@ static const struct starfive_dwmac_data
> > jh7100_data = {  static const struct of_device_id starfive_dwmac_match[] = {
> >  	{ .compatible = "starfive,jh7100-dwmac", .data = &jh7100_data },
> >  	{ .compatible = "starfive,jh7110-dwmac" },
> > +	{ .compatible = "starfive,jhb100-dwmac" },
> >  	{ /* sentinel */ }
> >  };
> >  MODULE_DEVICE_TABLE(of, starfive_dwmac_match);
> > --
> > 2.17.1
> >
> Reviewed-by: Sai Krishna <saikrishnag@xxxxxxxxxxx>