Re: [PATCH net-next v2 5/6] net: stmmac: add support for RZ/N1 GMAC

["Russell King (Oracle)" <linux@armlinux.org.uk>]

On Wed, Feb 08, 2023 at 05:42:02PM +0100, Clément Léger wrote:
> Add support for Renesas RZ/N1 GMAC. This support uses a custom PCS (MIIC)
> which is handle by parsing the pcs-handle device tree property.
> 
> Signed-off-by: Clément Léger <clement.leger@bootlin.com>
> ---
>  drivers/net/ethernet/stmicro/stmmac/Kconfig   |  11 ++
>  drivers/net/ethernet/stmicro/stmmac/Makefile  |   1 +
>  .../net/ethernet/stmicro/stmmac/dwmac-rzn1.c  | 120 ++++++++++++++++++
>  3 files changed, 132 insertions(+)
>  create mode 100644 drivers/net/ethernet/stmicro/stmmac/dwmac-rzn1.c
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/Kconfig b/drivers/net/ethernet/stmicro/stmmac/Kconfig
> index f77511fe4e87..be5429b7e192 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/Kconfig
> +++ b/drivers/net/ethernet/stmicro/stmmac/Kconfig
> @@ -153,6 +153,17 @@ config DWMAC_ROCKCHIP
>  	  This selects the Rockchip RK3288 SoC glue layer support for
>  	  the stmmac device driver.
>  
> +config DWMAC_RZN1
> +	tristate "Renesas RZ/N1 dwmac support"
> +	default ARCH_RZN1
> +	depends on OF && (ARCH_RZN1 || COMPILE_TEST)
> +	select PCS_RZN1_MIIC
> +	help
> +	  Support for Ethernet controller on Renesas RZ/N1 SoC family.
> +
> +	  This selects the Renesas RZ/N1 SoC glue layer support for
> +	  the stmmac device driver.
> +
>  config DWMAC_SOCFPGA
>  	tristate "SOCFPGA dwmac support"
>  	default ARCH_INTEL_SOCFPGA
> diff --git a/drivers/net/ethernet/stmicro/stmmac/Makefile b/drivers/net/ethernet/stmicro/stmmac/Makefile
> index 057e4bab5c08..53a0f74c1cb5 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/Makefile
> +++ b/drivers/net/ethernet/stmicro/stmmac/Makefile
> @@ -22,6 +22,7 @@ obj-$(CONFIG_DWMAC_MESON)	+= dwmac-meson.o dwmac-meson8b.o
>  obj-$(CONFIG_DWMAC_OXNAS)	+= dwmac-oxnas.o
>  obj-$(CONFIG_DWMAC_QCOM_ETHQOS)	+= dwmac-qcom-ethqos.o
>  obj-$(CONFIG_DWMAC_ROCKCHIP)	+= dwmac-rk.o
> +obj-$(CONFIG_DWMAC_RZN1)	+= dwmac-rzn1.o
>  obj-$(CONFIG_DWMAC_SOCFPGA)	+= dwmac-altr-socfpga.o
>  obj-$(CONFIG_DWMAC_STI)		+= dwmac-sti.o
>  obj-$(CONFIG_DWMAC_STM32)	+= dwmac-stm32.o
> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-rzn1.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-rzn1.c
> new file mode 100644
> index 000000000000..82118d8cb50e
> --- /dev/null
> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-rzn1.c
> @@ -0,0 +1,120 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (C) 2022 Schneider-Electric
> + *
> + * Clément Léger <clement.leger@bootlin.com>
> + */
> +
> +#include <linux/of.h>
> +#include <linux/pcs-rzn1-miic.h>
> +#include <linux/phylink.h>
> +#include <linux/platform_device.h>
> +
> +#include "stmmac_platform.h"
> +#include "stmmac.h"
> +
> +struct rzn1_dwmac {
> +	struct phylink_pcs *pcs;
> +};

I don't understand why you need this...

> +
> +static int rzn1_dt_parse(struct device *dev, struct rzn1_dwmac *dwmac)

You could pass a pointer to struct plat_stmmacenet_data into here, and
have it fill in your new ->pcs directly, and save the extra devm
allocations.

> +{
> +	struct device_node *np = dev->of_node;
> +	struct device_node *pcs_node;
> +	struct phylink_pcs *pcs;
> +	int ret;
> +
> +	pcs_node = of_parse_phandle(np, "pcs-handle", 0);
> +	if (!pcs_node)
> +		return 0;
> +
> +	pcs = miic_create(dev, pcs_node);

Don't you need to put pcs_node?

> +	if (IS_ERR(pcs))
> +		return PTR_ERR(pcs);
> +
> +	ret = miic_early_setup(pcs, dev);
> +	if (ret) {
> +		miic_destroy(pcs);
> +		return ret;
> +	}
> +
> +	dwmac->pcs = pcs;
> +
> +	return 0;
> +}
> +
> +static int rzn1_dwmac_probe(struct platform_device *pdev)
> +{
> +	struct plat_stmmacenet_data *plat_dat;
> +	struct stmmac_resources stmmac_res;
> +	struct device *dev = &pdev->dev;
> +	struct rzn1_dwmac *dwmac;
> +	int ret;
> +
> +	ret = stmmac_get_platform_resources(pdev, &stmmac_res);
> +	if (ret)
> +		return ret;
> +
> +	plat_dat = stmmac_probe_config_dt(pdev, stmmac_res.mac);
> +	if (IS_ERR(plat_dat))
> +		return PTR_ERR(plat_dat);
> +
> +	dwmac = devm_kzalloc(dev, sizeof(*dwmac), GFP_KERNEL);
> +	if (!dwmac) {
> +		ret = -ENOMEM;
> +		goto err_remove_config_dt;
> +	}
> +
> +	ret = rzn1_dt_parse(dev, dwmac);
> +	if (ret)
> +		goto err_remove_config_dt;
> +
> +	plat_dat->bsp_priv = dwmac;

You could set this to point back to plat_dat.

> +	plat_dat->pcs = dwmac->pcs;
> +
> +	ret = stmmac_dvr_probe(dev, plat_dat, &stmmac_res);
> +	if (ret)
> +		goto err_free_pcs;
> +
> +	return 0;
> +
> +err_free_pcs:
> +	if (dwmac->pcs)
> +		miic_destroy(dwmac->pcs);
> +
> +err_remove_config_dt:
> +	stmmac_remove_config_dt(pdev, plat_dat);
> +
> +	return ret;
> +}
> +
> +static int rzn1_dwmac_remove(struct platform_device *pdev)
> +{
> +	struct rzn1_dwmac *dwmac = get_stmmac_bsp_priv(&pdev->dev);

... which means you get plat_dat back here...

> +	int ret = stmmac_dvr_remove(&pdev->dev);
> +
> +	if (dwmac->pcs)
> +		miic_destroy(dwmac->pcs);

and can still destroy the pcs.

-- 
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