Re: [PATCH v2 2/2] ethernet: stmmac: dwmac-rk: Add GMAC support for RK3576

[Detlev Casanova <detlev.casanova@collabora.com>]

On Friday, 9 August 2024 09:16:44 EDT Heiko Stübner wrote:
> Hi Detlev,
> 
> Am Donnerstag, 8. August 2024, 19:00:18 CEST schrieb Detlev Casanova:
> > From: David Wu <david.wu@rock-chips.com>
> > 
> > Add constants and callback functions for the dwmac on RK3576 soc.
> > 
> > Signed-off-by: David Wu <david.wu@rock-chips.com>
> > [rebase, extracted bindings]
> > Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
> > ---
> > 
> >  .../net/ethernet/stmicro/stmmac/dwmac-rk.c    | 156 ++++++++++++++++++
> >  1 file changed, 156 insertions(+)
> > 
> > diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> > b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c index
> > 7ae04d8d291c8..e1fa8fc9f4012 100644
> > --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> > +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
> > @@ -1116,6 +1116,161 @@ static const struct rk_gmac_ops rk3568_ops = {
> > 
> >  	},
> >  
> >  };
> > 

[...]

> > +/* SDGMAC_GRF */
> > +#define RK3576_GRF_GMAC_CON0			0X0020
> > +#define RK3576_GRF_GMAC_CON1			0X0024
> > +
> > +#define RK3576_GMAC_RMII_MODE			GRF_BIT(3)
> > +#define RK3576_GMAC_RGMII_MODE			GRF_CLR_BIT(3)
> > +
> > +#define RK3576_GMAC_CLK_SELET_IO		GRF_BIT(7)
> > +#define RK3576_GMAC_CLK_SELET_CRU		GRF_CLR_BIT(7)
> 
> nit: typos _CLK_SELECT_ ... missing the C in select

Ack

> > +
> > +#define RK3576_GMAC_CLK_RMII_DIV2		GRF_BIT(5)
> > +#define RK3576_GMAC_CLK_RMII_DIV20		GRF_CLR_BIT(5)
> 
> I think those are backwards
> The TRM says bit[5]=0: 25MHz (DIV2) and bit[5]=1: 2.5MHz (DIV20)
> 
> I guess nobody also on Rockchip's side tested a RMII phy on those controllrs

Can't be sure about that. An error in the TRM is not impossible either, as for 
rk3588, it is also bit[5]=0: DIV20 and bit[5]=1: DIV2. I can switch them to 
match the TRM though, we may never now.

> > +
> > +#define RK3576_GMAC_CLK_RGMII_DIV1		\
> > +			(GRF_CLR_BIT(6) | GRF_CLR_BIT(5))
> > +#define RK3576_GMAC_CLK_RGMII_DIV5		\
> > +			(GRF_BIT(6) | GRF_BIT(5))
> > +#define RK3576_GMAC_CLK_RGMII_DIV50		\
> > +			(GRF_BIT(6) | GRF_CLR_BIT(5))
> > +
> 
> in contrast, these are correct and match the TRM
> 
> > +#define RK3576_GMAC_CLK_RMII_GATE		GRF_BIT(4)
> > +#define RK3576_GMAC_CLK_RMII_NOGATE		GRF_CLR_BIT(4)
> > +
> > +static void rk3576_set_to_rgmii(struct rk_priv_data *bsp_priv,
> > +				int tx_delay, int rx_delay)
> > +{
> > +	struct device *dev = &bsp_priv->pdev->dev;
> > +	unsigned int offset_con;
> > +
> > +	if (IS_ERR(bsp_priv->grf) || IS_ERR(bsp_priv->php_grf)) {
> > +		dev_err(dev, "Missing rockchip,grf or rockchip,php_grf 
property\n");
> > +		return;
> > +	}
> > +
> > +	offset_con = bsp_priv->id == 1 ? RK3576_GRF_GMAC_CON1 :
> > +					 RK3576_GRF_GMAC_CON0;
> > +
> > +	regmap_write(bsp_priv->grf, offset_con, RK3576_GMAC_RGMII_MODE);
> > +
> > +	offset_con = bsp_priv->id == 1 ? RK3576_VCCIO0_1_3_IOC_CON4 :
> > +					 
RK3576_VCCIO0_1_3_IOC_CON2;
> > +
> > +	/* m0 && m1 delay enabled */
> > +	regmap_write(bsp_priv->php_grf, offset_con,
> > +		     DELAY_ENABLE(RK3576, tx_delay, rx_delay));
> > +	regmap_write(bsp_priv->php_grf, offset_con + 0x4,
> > +		     DELAY_ENABLE(RK3576, tx_delay, rx_delay));
> > +
> > +	/* m0 && m1 delay value */
> > +	regmap_write(bsp_priv->php_grf, offset_con,
> > +		     RK3576_GMAC_CLK_TX_DL_CFG(tx_delay) |
> > +		     RK3576_GMAC_CLK_RX_DL_CFG(rx_delay));
> > +	regmap_write(bsp_priv->php_grf, offset_con + 0x4,
> > +		     RK3576_GMAC_CLK_TX_DL_CFG(tx_delay) |
> > +		     RK3576_GMAC_CLK_RX_DL_CFG(rx_delay));
> > +}
> > +
> > +static void rk3576_set_to_rmii(struct rk_priv_data *bsp_priv)
> > +{
> > +	struct device *dev = &bsp_priv->pdev->dev;
> > +	unsigned int offset_con;
> > +
> > +	if (IS_ERR(bsp_priv->php_grf)) {
> > +		dev_err(dev, "%s: Missing rockchip,php_grf property\n", 
__func__);
> > +		return;
> > +	}
> > +
> > +	offset_con = bsp_priv->id == 1 ? RK3576_GRF_GMAC_CON1 :
> > +					 RK3576_GRF_GMAC_CON0;
> > +
> > +	regmap_write(bsp_priv->grf, offset_con, RK3576_GMAC_RMII_MODE);
> > +}
> > +
> > +static void rk3576_set_gmac_speed(struct rk_priv_data *bsp_priv, int
> > speed) +{
> > +	struct device *dev = &bsp_priv->pdev->dev;
> > +	unsigned int val = 0, offset_con;
> > +
> > +	switch (speed) {
> > +	case 10:
> > +		if (bsp_priv->phy_iface == PHY_INTERFACE_MODE_RMII)
> > +			val = RK3576_GMAC_CLK_RMII_DIV20;
> > +		else
> > +			val = RK3576_GMAC_CLK_RGMII_DIV50;
> 
> 		val = bsp_priv->phy_iface == PHY_INTERFACE_MODE_RMII ?
> 				RK3576_GMAC_CLK_RMII_DIV20 :
> 				RK3576_GMAC_CLK_RGMII_DIV50;
> perhaps?

This way matches how it is written in rk3588_set_gmac_speed(). I find that 
having similar code for similar functions helps reading and understanding it 
better (although I agree that your suggestion looks better).

I'd rather keep it like it is for now if that's ok.

> > +		break;
> > +	case 100:
> > +		if (bsp_priv->phy_iface == PHY_INTERFACE_MODE_RMII)
> > +			val = RK3576_GMAC_CLK_RMII_DIV2;
> > +		else
> > +			val = RK3576_GMAC_CLK_RGMII_DIV5;
> 
> same as above?
> 
> > +		break;
> > +	case 1000:
> > +		if (bsp_priv->phy_iface != PHY_INTERFACE_MODE_RMII)
> > +			val = RK3576_GMAC_CLK_RGMII_DIV1;
> > +		else
> > +			goto err;
> 
> 		if (bsp_priv->phy_iface == PHY_INTERFACE_MODE_RMII)
> 			goto err;
> 
> 		val = RK3576_GMAC_CLK_RGMII_DIV1;
> 
> > +		break;
> > +	default:
> > +		goto err;
> > +	}
> > +
> > +	offset_con = bsp_priv->id == 1 ? RK3576_GRF_GMAC_CON1 :
> > +					 RK3576_GRF_GMAC_CON0;
> > +
> > +	regmap_write(bsp_priv->grf, offset_con, val);
> > +
> > +	return;
> > +err:
> > +	dev_err(dev, "unknown speed value for GMAC speed=%d", speed);
> > +}
> > +
> > +static void rk3576_set_clock_selection(struct rk_priv_data *bsp_priv,
> > bool input, +				       bool enable)
> > +{
> > +	unsigned int val = input ? RK3576_GMAC_CLK_SELET_IO :
> > +				   RK3576_GMAC_CLK_SELET_CRU;
> > +	unsigned int offset_con;
> > +
> > +	val |= enable ? RK3576_GMAC_CLK_RMII_NOGATE :
> > +			RK3576_GMAC_CLK_RMII_GATE;
> > +
> > +	offset_con = bsp_priv->id == 1 ? RK3576_GRF_GMAC_CON1 :
> > +					 RK3576_GRF_GMAC_CON0;
> 
> nit: alignment of both looks like it could be nicer

That's strange, the alignments looks good in vim and git diff. It also looks 
nice on the archive: https://lore.kernel.org/linux-rockchip/
20240808170113.82775-3-detlev.casanova@collabora.com/
 

Regards,
Detlev