Re: [PATCH 4/5] net: stmmac: Add glue layer for Loongson-1 SoC

[Simon Horman <horms@kernel.org>]

On Sat, Aug 12, 2023 at 11:11:34PM +0800, Keguang Zhang wrote:
> This glue driver is created based on the arch-code
> implemented earlier with the platform-specific settings.
> 
> Use syscon for SYSCON register access.
> 
> Partialy based on the previous work by Serge Semin.
> 
> Signed-off-by: Keguang Zhang <keguang.zhang@gmail.com>

...

Hi Keguang Zhang,

some minor feedback from my side.

> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson1.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson1.c

...

> +const struct reg_field ls1b_dwmac_syscon_regfields[] = {
> +	[GMAC1_USE_UART1]	= REG_FIELD(LS1X_SYSCON0, 4, 4),
> +	[GMAC1_USE_UART0]	= REG_FIELD(LS1X_SYSCON0, 3, 3),
> +	[GMAC1_SHUT]		= REG_FIELD(LS1X_SYSCON1, 13, 13),
> +	[GMAC0_SHUT]		= REG_FIELD(LS1X_SYSCON1, 12, 12),
> +	[GMAC1_USE_TXCLK]	= REG_FIELD(LS1X_SYSCON1, 3, 3),
> +	[GMAC0_USE_TXCLK]	= REG_FIELD(LS1X_SYSCON1, 2, 2),
> +	[GMAC1_USE_PWM23]	= REG_FIELD(LS1X_SYSCON1, 1, 1),
> +	[GMAC0_USE_PWM01]	= REG_FIELD(LS1X_SYSCON1, 0, 0)
> +};

nit: Perhaps ls1b_dwmac_syscon_regfields should be static.

> +
> +const struct reg_field ls1c_dwmac_syscon_regfields[] = {
> +	[GMAC_SHUT]		= REG_FIELD(LS1X_SYSCON0, 6, 6),
> +	[PHY_INTF_SELI]		= REG_FIELD(LS1X_SYSCON1, 28, 30)
> +};

Likewise, perhaps ls1c_dwmac_syscon_regfields should be static.

...

> +static const struct of_device_id ls1x_dwmac_syscon_match[] = {
> +	{ .compatible = "loongson,ls1b-syscon", .data = &ls1b_dwmac_syscon },
> +	{ .compatible = "loongson,ls1c-syscon", .data = &ls1c_dwmac_syscon },
> +	{ }
> +};o

I am seeing a warning about ls1x_dwmac_syscon_match being unused.
I think this is due to CONFIG_OF being unset.

> +
> +static int ls1x_dwmac_probe(struct platform_device *pdev)
> +{
> +	struct plat_stmmacenet_data *plat_dat;
> +	struct stmmac_resources stmmac_res;
> +	struct device_node *syscon_np;
> +	const struct of_device_id *match;
> +	struct regmap *regmap;
> +	struct ls1x_dwmac *dwmac;
> +	const struct ls1x_dwmac_syscon *syscon;
> +	size_t size;
> +	int ret;
> +
> +	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
> +	if (ret)
> +		return ret;
> +
> +	/* Probe syscon */
> +	syscon_np = of_parse_phandle(pdev->dev.of_node, "syscon", 0);
> +	if (!syscon_np)
> +		return -ENODEV;
> +
> +	match = of_match_node(ls1x_dwmac_syscon_match, syscon_np);
> +	if (!match) {
> +		of_node_put(syscon_np);
> +		return -EINVAL;
> +	}
> +	syscon = (const struct ls1x_dwmac_syscon *)match->data;
> +
> +	regmap = syscon_node_to_regmap(syscon_np);
> +	of_node_put(syscon_np);
> +	if (IS_ERR(regmap)) {
> +		ret = PTR_ERR(regmap);
> +		dev_err(&pdev->dev, "Unable to map syscon: %d\n", ret);
> +		return ret;
> +	}
> +
> +	size = syscon->nr_reg_fields * sizeof(struct regmap_field *);
> +	dwmac = devm_kzalloc(&pdev->dev, sizeof(*dwmac) + size, GFP_KERNEL);
> +	if (!dwmac)
> +		return -ENOMEM;
> +
> +	plat_dat = stmmac_probe_config_dt(pdev, stmmac_res.mac);
> +	if (IS_ERR(plat_dat)) {
> +		dev_err(&pdev->dev, "dt configuration failed\n");
> +		return PTR_ERR(plat_dat);
> +	}
> +
> +	plat_dat->bsp_priv = dwmac;
> +	plat_dat->init = ls1x_dwmac_init;
> +	dwmac->dev = &pdev->dev;
> +	dwmac->plat_dat = plat_dat;
> +	dwmac->syscon = syscon;
> +	dwmac->regmap = regmap;
> +
> +	ret = stmmac_pltfr_probe(pdev, plat_dat, &stmmac_res);
> +	if (ret)
> +		goto err_remove_config_dt;
> +
> +	return 0;
> +
> +err_remove_config_dt:
> +	if (pdev->dev.of_node)
> +		stmmac_remove_config_dt(pdev, plat_dat);
> +
> +	return ret;
> +}

...