[PATCH 3/8] net: dwc_eth_qos: Add option "snps,reset-gpio" phy-rst gpio for stm32

[Patrice CHOTARD <patrice.chotard@st.com>]

Hi David

On 4/30/20 12:36 PM, David Wu wrote:
> It can be seen that most of the Socs using STM mac, "snps,reset-gpio"
> gpio is used, adding this option makes reset function more general.
>
> Signed-off-by: David Wu <david.wu@rock-chips.com>
> ---
>
>  drivers/net/dwc_eth_qos.c | 40 ++++++++++++++++++++++++++++++++++-----
>  1 file changed, 35 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/dwc_eth_qos.c b/drivers/net/dwc_eth_qos.c
> index 16988f6bdc..06a8d924a7 100644
> --- a/drivers/net/dwc_eth_qos.c
> +++ b/drivers/net/dwc_eth_qos.c
> @@ -298,6 +298,7 @@ struct eqos_priv {
>  	struct eqos_tegra186_regs *tegra186_regs;
>  	struct reset_ctl reset_ctl;
>  	struct gpio_desc phy_reset_gpio;
> +	u32 reset_delays[3];
>  	struct clk clk_master_bus;
>  	struct clk clk_rx;
>  	struct clk clk_ptp_ref;
> @@ -701,6 +702,15 @@ static int eqos_start_resets_stm32(struct udevice *dev)
>  
>  	debug("%s(dev=%p):\n", __func__, dev);
>  	if (dm_gpio_is_valid(&eqos->phy_reset_gpio)) {
> +		ret = dm_gpio_set_value(&eqos->phy_reset_gpio, 0);
> +		if (ret < 0) {
> +			pr_err("dm_gpio_set_value(phy_reset, deassert) failed: %d",
> +			       ret);
> +			return ret;
> +		}
> +
> +		udelay(eqos->reset_delays[0]);
> +
not related to this patch subject
>  		ret = dm_gpio_set_value(&eqos->phy_reset_gpio, 1);
>  		if (ret < 0) {
>  			pr_err("dm_gpio_set_value(phy_reset, assert) failed: %d",
> @@ -708,7 +718,7 @@ static int eqos_start_resets_stm32(struct udevice *dev)
>  			return ret;
>  		}
>  
> -		udelay(2);
> +		udelay(eqos->reset_delays[1]);
>  
>  		ret = dm_gpio_set_value(&eqos->phy_reset_gpio, 0);
>  		if (ret < 0) {
> @@ -716,6 +726,8 @@ static int eqos_start_resets_stm32(struct udevice *dev)
>  			       ret);
>  			return ret;
>  		}
> +
> +		udelay(eqos->reset_delays[2]);
>  	}
>  	debug("%s: OK\n", __func__);
>  
> @@ -1065,16 +1077,16 @@ static int eqos_start(struct udevice *dev)
>  	val |= EQOS_DMA_MODE_SWR;
>  	writel(val, &eqos->dma_regs->mode);
>  	limit = eqos->config->swr_wait / 10;
> -	while (limit--) {
> +	do {
>  		if (!(readl(&eqos->dma_regs->mode) & EQOS_DMA_MODE_SWR))
>  			break;
>  		mdelay(10000);
> -	}
> +	} while (limit--);
why are you updating this ? it's not related to the purpose of this patch
>  
>  	if (limit < 0) {
>  		pr_err("EQOS_DMA_MODE_SWR stuck");
> -		goto err_stop_clks;
> -		return -ETIMEDOUT;
> +		ret = -ETIMEDOUT;
> +		goto err_stop_resets;
ditto
>  	}
>  
>  	ret = eqos->config->ops->eqos_calibrate_pads(dev);
> @@ -1712,11 +1724,29 @@ static int eqos_probe_resources_stm32(struct udevice *dev)
>  		if (ret)
>  			pr_warn("gpio_request_by_name(phy reset) not provided %d",
>  				ret);
> +		else
> +			eqos->reset_delays[1] = 2;
this is not the correct place to set default value. It must be set in case we can't get value from DT below
>  
>  		eqos->phyaddr = ofnode_read_u32_default(phandle_args.node,
>  							"reg", -1);
>  	}
>  
> +	if (!dm_gpio_is_valid(&eqos->phy_reset_gpio)) {
> +		int reset_flags = GPIOD_IS_OUT;
> +
> +		if (dev_read_bool(dev, "snps,reset-active-low"))
> +			reset_flags |= GPIOD_ACTIVE_LOW;
> +
> +		ret = gpio_request_by_name(dev, "snps,reset-gpio", 0,
> +					   &eqos->phy_reset_gpio, reset_flags);
> +		if (ret == 0)
> +			ret = dev_read_u32_array(dev, "snps,reset-delays-us",
> +						 eqos->reset_delays, 3);
in case "snps,reset-delays-us" is not in present DT, all resets-delays are set to 0, see my remark above
> +		else
> +			pr_warn("gpio_request_by_name(snps,reset-gpio) failed: %d",
> +				ret);
> +	}
> +
>  	debug("%s: OK\n", __func__);
>  	return 0;
>