[PATCH 1/4] net: ethernet: dwmac: add Ethernet glue logic for stm32 chip
Alexandre Torgue
alexandre.torgue at gmail.com
Mon Feb 22 06:50:46 PST 2016
2016-02-13 14:48 GMT+01:00 Joachim Eastwood <manabian at gmail.com>:
> On 3 February 2016 at 15:54, Alexandre TORGUE
> <alexandre.torgue at gmail.com> wrote:
>> stm324xx family chips support Synopsys MAC 3.510 IP.
>> This patch adds settings for logical glue logic:
>> -clocks
>> -mode selection MII or RMII.
>>
>> Signed-off-by: Alexandre TORGUE <alexandre.torgue at gmail.com>
>>
>> diff --git a/drivers/net/ethernet/stmicro/stmmac/Kconfig b/drivers/net/ethernet/stmicro/stmmac/Kconfig
>> index cec147d..a94dd15 100644
>> --- a/drivers/net/ethernet/stmicro/stmmac/Kconfig
>> +++ b/drivers/net/ethernet/stmicro/stmmac/Kconfig
>> @@ -114,6 +114,18 @@ config DWMAC_SUNXI
>> This selects Allwinner SoC glue layer support for the
>> stmmac device driver. This driver is used for A20/A31
>> GMAC ethernet controller.
>> +
>> +config DWMAC_STM32
>> + tristate "STM32 DWMAC support"
>> + default ARCH_STM32
>> + depends on OF
>> + select MFD_SYSCON
>> + ---help---
>> + Support for ethernet controller on STM32 SOCs.
>> +
>> + This selects STM32 SoC glue layer support for the stmmac
>> + device driver. This driver is used on for the STM32 series
>> + SOCs GMAC ethernet controller.
>> endif
>>
>> config STMMAC_PCI
>> diff --git a/drivers/net/ethernet/stmicro/stmmac/Makefile b/drivers/net/ethernet/stmicro/stmmac/Makefile
>> index b390161..9fb2061 100644
>> --- a/drivers/net/ethernet/stmicro/stmmac/Makefile
>> +++ b/drivers/net/ethernet/stmicro/stmmac/Makefile
>> @@ -14,6 +14,7 @@ obj-$(CONFIG_DWMAC_SOCFPGA) += dwmac-socfpga.o
>> obj-$(CONFIG_DWMAC_STI) += dwmac-sti.o
>> obj-$(CONFIG_DWMAC_SUNXI) += dwmac-sunxi.o
>> obj-$(CONFIG_DWMAC_GENERIC) += dwmac-generic.o
>> +obj-$(CONFIG_DWMAC_STM32) += dwmac-stm32.o
>
> Keep these sorted. There also a comment in the Makefile that states
> that the generic should always be last.
ok
>
>
>> stmmac-platform-objs:= stmmac_platform.o
>>
>> obj-$(CONFIG_STMMAC_PCI) += stmmac-pci.o
>> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c
>> new file mode 100644
>> index 0000000..56ccc20
>> --- /dev/null
>> +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-stm32.c
>> @@ -0,0 +1,177 @@
>> +/*
>> + * dwmac-stm32.c - DWMAC Specific Glue layer for STM32 MCU
>> + *
>> + * Copyright (C) Alexandre Torgue 2015
>> + * Author: Alexandre Torgue <alexandre.torgue at gmail.com>
>> + * License terms: GNU General Public License (GPL), version 2
>> + *
>> + */
>> +
>> +#include <linux/kernel.h>
>> +#include <linux/slab.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/stmmac.h>
>> +#include <linux/phy.h>
>> +#include <linux/mfd/syscon.h>
>> +#include <linux/module.h>
>> +#include <linux/regmap.h>
>> +#include <linux/clk.h>
>> +#include <linux/of.h>
>> +#include <linux/of_device.h>
>> +#include <linux/of_net.h>
>
> Consider sorting the includes.
ok
>
>> +
>> +#include "stmmac_platform.h"
>> +
>> +#define MII_PHY_SEL_MASK BIT(23)
>> +
>> +struct stm32_dwmac {
>> + int interface; /* MII interface */
>> + struct clk *clk_tx;
>> + struct clk *clk_rx;
>> + u32 mode_reg; /* MAC glue-logic mode register */
>> + struct device *dev;
>
> dev doesn't seem to be used anywhere.
ok
>
>> + struct regmap *regmap;
>> + u32 speed;
>> +};
>> +
>> +static int stm32_dwmac_init(struct platform_device *pdev, void *priv)
>> +{
>> + struct stm32_dwmac *dwmac = priv;
>> + struct regmap *regmap = dwmac->regmap;
>> + int ret, iface = dwmac->interface;
>> + u32 reg = dwmac->mode_reg;
>> + u32 val;
>> +
>> + if (dwmac->clk_tx)
>> + ret = clk_prepare_enable(dwmac->clk_tx);
>
> The clk API handles a NULL clk so you don't really need to check for it.
I agree
>
>
>> + if (ret)
>> + goto out;
>> +
>> + if (dwmac->clk_rx)
>> + ret = clk_prepare_enable(dwmac->clk_rx);
>
> Same here.
I agree
>
>
>> + if (ret)
>> + goto out_disable_clk_tx;
>> +
>> + val = (iface == PHY_INTERFACE_MODE_MII) ? 0 : 1;
>> + ret = regmap_update_bits(regmap, reg, MII_PHY_SEL_MASK, val);
>> + if (ret)
>> + goto out_disable_clk_tx_rx;
>> +
>> + return 0;
>> +
>> +out_disable_clk_tx_rx:
>> + clk_disable_unprepare(dwmac->clk_rx);
>> +out_disable_clk_tx:
>> + clk_disable_unprepare(dwmac->clk_tx);
>> +out:
>> + return ret;
>> +}
>> +
>> +static void stm32_dwmac_exit(struct platform_device *pdev, void *priv)
>> +{
>> + struct stm32_dwmac *dwmac = priv;
>> +
>> + if (dwmac->clk_tx)
>> + clk_disable_unprepare(dwmac->clk_tx);
>> + if (dwmac->clk_rx)
>> + clk_disable_unprepare(dwmac->clk_rx);
>
> Same here.
I agree
>
>
>> +}
>> +
>> +static int stm32_dwmac_parse_data(struct stm32_dwmac *dwmac,
>> + struct platform_device *pdev)
>> +{
>> + struct device *dev = &pdev->dev;
>> + struct device_node *np = dev->of_node;
>> + struct regmap *regmap;
>> + int err;
>> +
>> + if (!np)
>> + return -EINVAL;
>
> Can this ever happen?
> This is a DT only driver, right?
You're right. It is only DT.
>
>> +
>> + /* Get TX/RX clocks */
>> + dwmac->clk_tx = devm_clk_get(dev, "tx-clk");
>> + if (IS_ERR(dwmac->clk_tx)) {
>> + dev_warn(dev, "No tx clock provided...\n");
>> + dwmac->clk_tx = NULL;
>> + }
>> + dwmac->clk_rx = devm_clk_get(dev, "rx-clk");
>> + if (IS_ERR(dwmac->clk_rx)) {
>> + dev_warn(dev, "No rx clock provided...\n");
>> + dwmac->clk_rx = NULL;
>> + }
>> +
>> + /* Get mode register */
>> + regmap = syscon_regmap_lookup_by_phandle(np, "st,syscon");
>> + if (IS_ERR(regmap))
>> + return PTR_ERR(regmap);
>> +
>> + err = of_property_read_u32_index(np, "st,syscon", 1, &dwmac->mode_reg);
>> + if (err) {
>> + dev_err(dev, "Can't get sysconfig mode offset (%d)\n", err);
>> + return err;
>> + }
>> +
>> + dwmac->dev = dev;
>> + dwmac->interface = of_get_phy_mode(np);
>> + dwmac->regmap = regmap;
>> +
>> + return 0;
>> +}
>> +
>> +static int stm32_dwmac_probe(struct platform_device *pdev)
>> +{
>> + struct plat_stmmacenet_data *plat_dat;
>> + struct stmmac_resources stmmac_res;
>> + struct stm32_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(&pdev->dev, sizeof(*dwmac), GFP_KERNEL);
>> + if (!dwmac)
>> + return -ENOMEM;
>> +
>> + ret = stm32_dwmac_parse_data(dwmac, pdev);
>> + if (ret) {
>> + dev_err(&pdev->dev, "Unable to parse OF data\n");
>> + return ret;
>> + }
>> +
>> + plat_dat->bsp_priv = dwmac;
>> + plat_dat->init = stm32_dwmac_init;
>> + plat_dat->exit = stm32_dwmac_exit;
>
> Instead of using these callbacks could you rather implement the PM
> callbacks directly in this driver?
> I don't think it should add much code and it will make it look more
> like standard driver. This will also give you some more control and
> flexibility in your code.
I prefer to keep the code as it is. Glue layer is directly linked to
stmmac driver and I don't want to brake the link between the glue and
the stmmac driver.
>
>> +
>> + ret = stm32_dwmac_init(pdev, plat_dat->bsp_priv);
>> + if (ret)
>> + return ret;
>> +
>> + return stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
>> +}
>> +
>> +static const struct of_device_id stm32_dwmac_match[] = {
>> + { .compatible = "st,stm32-dwmac"},
>> + { }
>> +};
>> +MODULE_DEVICE_TABLE(of, stm32_dwmac_match);
>> +
>> +static struct platform_driver stm32_dwmac_driver = {
>> + .probe = stm32_dwmac_probe,
>> + .remove = stmmac_pltfr_remove,
>
> Could you implement the .remove callback in your driver instead of
> using stmmac_pltfr_remove?
> Same reasons as above.
As explain above, I prefere to keep the code as it is in order to not
remove glue layer before the stmmac driver.
>
>
>> + .driver = {
>> + .name = "stm32-dwmac",
>> + .pm = &stmmac_pltfr_pm_ops,
>> + .of_match_table = stm32_dwmac_match,
>> + },
>> +};
>> +module_platform_driver(stm32_dwmac_driver);
>> +
>> +MODULE_AUTHOR("Alexandre Torgue <alexandre.torgue at gmail.com>");
>> +MODULE_DESCRIPTION("STMicroelectronics MCU DWMAC Specific Glue layer");
>> +MODULE_LICENSE("GPL");
>
> Since you state:
>> + * License terms: GNU General Public License (GPL), version 2
>
> You might want to switch use: MODULE_LICENSE("GPL v2");
>
I agree.
>
> regards,
> Joachim Eastwood
Thanks Joachim for the review and remarks. Main will be corrected in
next patch version.
regards
Alexandre Torgue
More information about the linux-arm-kernel
mailing list