diff mbox

[v4,1/4] ethernet: arc: Add support for Rockchip SoC layer device tree bindings

Message ID 1409740036-8117-1-git-send-email-romain.perier@gmail.com
State New, archived
Headers show

Commit Message

Romain Perier Sept. 3, 2014, 10:27 a.m. UTC
This patch defines a platform glue layer for Rockchip SoCs which
support arc-emac driver. It ensures that regulator for the rmii is on
before trying to connect to the ethernet controller. It applies right
speed and mode changes to the grf when ethernet settings change.

Signed-off-by: Romain Perier <romain.perier@gmail.com>
---
 drivers/net/ethernet/arc/Kconfig         |  10 ++
 drivers/net/ethernet/arc/Makefile        |   1 +
 drivers/net/ethernet/arc/emac.h          |   4 +-
 drivers/net/ethernet/arc/emac_main.c     |   2 +
 drivers/net/ethernet/arc/emac_rockchip.c | 228 +++++++++++++++++++++++++++++++
 5 files changed, 244 insertions(+), 1 deletion(-)
 create mode 100644 drivers/net/ethernet/arc/emac_rockchip.c

Comments

Varka Bhadram Sept. 3, 2014, 10:42 a.m. UTC | #1
On 09/03/2014 03:57 PM, Romain Perier wrote:
> This patch defines a platform glue layer for Rockchip SoCs which
> support arc-emac driver. It ensures that regulator for the rmii is on
> before trying to connect to the ethernet controller. It applies right
> speed and mode changes to the grf when ethernet settings change.
>
> Signed-off-by: Romain Perier <romain.perier@gmail.com>
> ---
>   drivers/net/ethernet/arc/Kconfig         |  10 ++
>   drivers/net/ethernet/arc/Makefile        |   1 +
>   drivers/net/ethernet/arc/emac.h          |   4 +-
>   drivers/net/ethernet/arc/emac_main.c     |   2 +
>   drivers/net/ethernet/arc/emac_rockchip.c | 228 +++++++++++++++++++++++++++++++
>   5 files changed, 244 insertions(+), 1 deletion(-)
>   create mode 100644 drivers/net/ethernet/arc/emac_rockchip.c
>
> diff --git a/drivers/net/ethernet/arc/Kconfig b/drivers/net/ethernet/arc/Kconfig
> index 89e04fd..8e262e2 100644
> --- a/drivers/net/ethernet/arc/Kconfig
> +++ b/drivers/net/ethernet/arc/Kconfig
> @@ -32,4 +32,14 @@ config ARC_EMAC
>   	  non-standard on-chip ethernet device ARC EMAC 10/100 is used.
>   	  Say Y here if you have such a board.  If unsure, say N.
>   
> +config EMAC_ROCKCHIP
> +	tristate "Rockchip EMAC support"
> +	select ARC_EMAC_CORE
> +	depends on OF_IRQ && OF_NET && REGULATOR
> +	---help---
> +	  Support for Rockchip RK3066/RK3188 EMAC ethernet controllers.
> +	  This selects Rockchip SoC glue layer support for the
> +	  emac device driver. This driver is used for RK3066/RK3188
> +	  EMAC ethernet controller.
> +
>   endif # NET_VENDOR_ARC
> diff --git a/drivers/net/ethernet/arc/Makefile b/drivers/net/ethernet/arc/Makefile
> index 241bb80..79108af 100644
> --- a/drivers/net/ethernet/arc/Makefile
> +++ b/drivers/net/ethernet/arc/Makefile
> @@ -5,3 +5,4 @@
>   arc_emac-objs := emac_main.o emac_mdio.o
>   obj-$(CONFIG_ARC_EMAC_CORE) += arc_emac.o
>   obj-$(CONFIG_ARC_EMAC) += emac_arc.o
> +obj-$(CONFIG_EMAC_ROCKCHIP) += emac_rockchip.o
> diff --git a/drivers/net/ethernet/arc/emac.h b/drivers/net/ethernet/arc/emac.h
> index eb2ba67..dae1ac3 100644
> --- a/drivers/net/ethernet/arc/emac.h
> +++ b/drivers/net/ethernet/arc/emac.h
> @@ -123,9 +123,11 @@ struct buffer_state {
>    * @speed:	PHY's last set speed.
>    */
>   struct arc_emac_priv {
> -	/* Devices */
>   	const char *drv_name;
>   	const char *drv_version;
> +	void (*set_mac_speed)(void *priv, unsigned int speed);
> +
> +	/* Devices */
>   	struct device *dev;
>   	struct phy_device *phy_dev;
>   	struct mii_bus *bus;
> diff --git a/drivers/net/ethernet/arc/emac_main.c b/drivers/net/ethernet/arc/emac_main.c
> index b35c69e..a08f343 100644
> --- a/drivers/net/ethernet/arc/emac_main.c
> +++ b/drivers/net/ethernet/arc/emac_main.c
> @@ -48,6 +48,8 @@ static void arc_emac_adjust_link(struct net_device *ndev)
>   	if (priv->speed != phy_dev->speed) {
>   		priv->speed = phy_dev->speed;
>   		state_changed = 1;
> +		if (priv->set_mac_speed)
> +			priv->set_mac_speed(priv, priv->speed);
>   	}
>   
>   	if (priv->duplex != phy_dev->duplex) {
> diff --git a/drivers/net/ethernet/arc/emac_rockchip.c b/drivers/net/ethernet/arc/emac_rockchip.c
> new file mode 100644
> index 0000000..97dffbc
> --- /dev/null
> +++ b/drivers/net/ethernet/arc/emac_rockchip.c
> @@ -0,0 +1,228 @@
> +/**
> + * emac-rockchip.c - Rockchip EMAC specific glue layer
> + *
> + * Copyright (C) 2014 Romain Perier <romain.perier@gmail.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/etherdevice.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/module.h>
> +#include <linux/of_net.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
> +
> +#include "emac.h"
> +
> +#define DRV_NAME        "rockchip_emac"
> +#define DRV_VERSION     "1.0"
> +
> +#define GRF_MODE_MII		(1UL << 0)
> +#define GRF_MODE_RMII		(0UL << 0)
> +#define GRF_SPEED_10M		(0UL << 1)
> +#define GRF_SPEED_100M		(1UL << 1)
> +#define GRF_SPEED_ENABLE_BIT	(1UL << 17)
> +#define GRF_MODE_ENABLE_BIT	(1UL << 16)
> +
> +struct emac_rockchip_soc_data {
> +	int grf_offset;
> +};
> +
> +struct rockchip_priv_data {
> +	struct arc_emac_priv emac;
> +	struct regmap *grf;
> +	const struct emac_rockchip_soc_data *soc_data;
> +	struct regulator *regulator;
> +	struct clk *refclk;
> +};
> +
> +static const struct emac_rockchip_soc_data emac_rockchip_dt_data[] = {
> +	{ .grf_offset = 0x154 }, /* rk3066 */
> +	{ .grf_offset = 0x0a4 }, /* rk3188 */
> +};
> +
> +static const struct of_device_id emac_rockchip_dt_ids[] = {
> +	{ .compatible = "rockchip,rk3066-emac", .data = &emac_rockchip_dt_data[0] },
> +	{ .compatible = "rockchip,rk3188-emac", .data = &emac_rockchip_dt_data[1] },
> +	{ /* Sentinel */ }
> +};
> +

of_device_id 's should be above probe/remove functionalities of the driver because we are
using *emac_rockchip_dt_ids* in probe function.

MODULE_DEVICE_TABLE(of, ...) should immediately follows the *of_device_id*
  

> +static void emac_rockchip_set_mac_speed(void *priv, unsigned int speed)
> +{
> +	struct rockchip_priv_data *emac = priv;
> +	u32 data;
> +	int err = 0;
> +
> +	/* write-enable bits */
> +	data = GRF_SPEED_ENABLE_BIT;
> +
> +	switch(speed) {
> +	case 10:
> +		data |= GRF_SPEED_10M;
> +		break;
> +	case 100:
> +		data |= GRF_SPEED_100M;
> +		break;
> +	default:
> +		pr_err("speed %u not supported\n", speed);
> +		return;
> +	}
> +
> +	err = regmap_write(emac->grf, emac->soc_data->grf_offset, data);
> +	if (err)
> +		pr_err("unable to apply speed %u to grf (%d)\n", speed, err);
> +}
> +
> +static int emac_rockchip_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct net_device *ndev;
> +	struct rockchip_priv_data *priv;
> +	const struct of_device_id *match;
> +	u32 data;
> +	int err, interface;
> +
> +	if (!pdev->dev.of_node)
> +		return -ENODEV;
> +
> +	ndev = alloc_etherdev(sizeof(struct rockchip_priv_data));
> +	if (!ndev)
> +		return -ENOMEM;
> +	platform_set_drvdata(pdev, ndev);
> +	SET_NETDEV_DEV(ndev, dev);
> +
> +	priv = netdev_priv(ndev);
> +	priv->emac.drv_name = DRV_NAME;
> +	priv->emac.drv_version = DRV_VERSION;
> +	priv->emac.set_mac_speed = emac_rockchip_set_mac_speed;
> +
> +	interface = of_get_phy_mode(dev->of_node);
> +
> +	/* RK3066 and RK3188 SoCs only support RMII */
> +	if (interface != PHY_INTERFACE_MODE_RMII) {
> +		dev_err(dev, "unsupported phy interface mode %d\n", interface);
> +		err = -ENOTSUPP;
> +		goto out_netdev;
> +	}
> +
> +	priv->grf = syscon_regmap_lookup_by_phandle(dev->of_node, "rockchip,grf");
> +	if (IS_ERR(priv->grf)) {
> +		dev_err(dev, "failed to retrieve global register file from the device tree (%ld)\n", PTR_ERR(priv->grf));

debug message is so lengthy ...?

we can omit *from device tree*

dev_err(dev, "failed to get global register file");

> +		err = PTR_ERR(priv->grf);
> +		goto out_netdev;
> +	}
> +
> +	match = of_match_node(emac_rockchip_dt_ids, dev->of_node);
> +	priv->soc_data = match->data;
> +
> +	priv->emac.clk = devm_clk_get(dev, "hclk");
> +	if (IS_ERR(priv->emac.clk)) {
> +		dev_err(dev, "failed to retrieve host clock from device tree (%ld)\n", PTR_ERR(priv->emac.clk));
> +		

dto...

> err = PTR_ERR(priv->emac.clk);
> +		goto out_netdev;
> +	}
> +
> +	priv->refclk = devm_clk_get(dev, "macref");
> +	if (IS_ERR(priv->refclk)) {
> +		dev_err(dev, "failed to retrieve reference clock from device tree (%ld)\n", PTR_ERR(priv->refclk));

dto...

> +		err = PTR_ERR(priv->refclk);
> +		goto out_netdev;
> +	}
> +
> +	err = clk_prepare_enable(priv->refclk);
> +	if (err) {
> +		dev_err(dev, "failed to enable reference clock (%d)\n", err);
> +		goto out_netdev;
> +	}
> +
> +	/* Optional regulator for PHY */
> +	priv->regulator = devm_regulator_get_optional(dev, "phy");
> +	if (IS_ERR(priv->regulator)) {
> +		if (PTR_ERR(priv->regulator) == -EPROBE_DEFER)
> +			return -EPROBE_DEFER;
> +		dev_err(dev, "no regulator found\n");
> +		priv->regulator = NULL;
> +	}
> +
> +	if (priv->regulator) {
> +		err = regulator_enable(priv->regulator);
> +		if (err) {
> +			dev_err(dev, "failed to enable phy-supply (%d)\n", err);
> +			goto out_clk_disable;
> +		}
> +	}
> +
> +	err = arc_emac_probe(ndev, interface);
> +	if (err)
> +		goto out_regulator_disable;
> +
> +	/* write-enable bits */
> +	data = GRF_MODE_ENABLE_BIT | GRF_SPEED_ENABLE_BIT;
> +
> +	data |= GRF_SPEED_100M;
> +	data |= GRF_MODE_RMII;
> +
> +	err = regmap_write(priv->grf, priv->soc_data->grf_offset, data);
> +	if (err) {
> +		dev_err(dev, "unable to apply initial settings to grf (%d)\n", err);
> +		goto out_regulator_disable;
> +	}
> +
> +	/* RMII interface needs always a rate of 50MHz */
> +	err = clk_set_rate(priv->refclk, 50000000);
> +	if (err)
> +		dev_err(dev, "failed to change reference clock rate (%d)\n", err);
> +	return 0;
> +
> +out_regulator_disable:
> +	if (priv->regulator)
> +		regulator_disable(priv->regulator);
> +out_clk_disable:
> +	clk_unprepare_disable(priv->refclk);
> +out_netdev:
> +	free_netdev(ndev);
> +	return err;
> +}
> +
> +static int emac_rockchip_remove(struct platform_device *pdev)
> +{
> +	struct net_device *ndev = platform_get_drvdata(pdev);
> +	struct rockchip_priv_data *priv = netdev_priv(ndev);
> +	int err;
> +
> +	clk_disable_unprepare(priv->refclk);
> +
> +	if (priv->regulator)
> +		regulator_disable(priv->regulator);
> +
> +	err = arc_emac_remove(ndev);
> +	free_netdev(ndev);
> +	return err;
> +}
> +
> +MODULE_DEVICE_TABLE(of, emac_rockchip_dt_ids);
> +

should be after *struct of_device_id*

> +static struct platform_driver emac_rockchip_driver = {
> +	.probe = emac_rockchip_probe,
> +	.remove = emac_rockchip_remove,
> +	.driver = {
> +		.name = DRV_NAME,
> +		.of_match_table  = emac_rockchip_dt_ids,
> +	},
> +};
> +
> +module_platform_driver(emac_rockchip_driver);
> +
> +MODULE_AUTHOR("Romain Perier <romain.perier@gmail.com>");
> +MODULE_DESCRIPTION("Rockchip EMAC platform driver");
> +MODULE_LICENSE("GPL");

Thanks....
Arnd Bergmann Sept. 3, 2014, 11:14 a.m. UTC | #2
On Wednesday 03 September 2014 10:27:13 Romain Perier wrote:
> +static const struct emac_rockchip_soc_data emac_rockchip_dt_data[] = {
> +       { .grf_offset = 0x154 }, /* rk3066 */
> +       { .grf_offset = 0x0a4 }, /* rk3188 */
> +};
> +
> +static const struct of_device_id emac_rockchip_dt_ids[] = {
> +       { .compatible = "rockchip,rk3066-emac", .data = &emac_rockchip_dt_data[0] },
> +       { .compatible = "rockchip,rk3188-emac", .data = &emac_rockchip_dt_data[1] },
> +       { /* Sentinel */ }
> +};
> +
> 

One last question: is this the location given as .grf_offset the
only thing in grf that is potentially of concern to this driver?

If it is, you can change the binding to include the register number
in the syscon reference, like

	rockchip,grf = <&grf 0x154>;

and then read it from there, to simplify the code needed to get the
number from the device id.

	Arnd
Heiko Stuebner Sept. 3, 2014, 12:20 p.m. UTC | #3
Am Mittwoch, 3. September 2014, 13:14:54 schrieb Arnd Bergmann:
> On Wednesday 03 September 2014 10:27:13 Romain Perier wrote:
> > +static const struct emac_rockchip_soc_data emac_rockchip_dt_data[] = {
> > +       { .grf_offset = 0x154 }, /* rk3066 */
> > +       { .grf_offset = 0x0a4 }, /* rk3188 */
> > +};
> > +
> > +static const struct of_device_id emac_rockchip_dt_ids[] = {
> > +       { .compatible = "rockchip,rk3066-emac", .data =
> > &emac_rockchip_dt_data[0] }, +       { .compatible =
> > "rockchip,rk3188-emac", .data = &emac_rockchip_dt_data[1] }, +       { /*
> > Sentinel */ }
> > +};
> > +
> 
> One last question: is this the location given as .grf_offset the
> only thing in grf that is potentially of concern to this driver?
> 
> If it is, you can change the binding to include the register number
> in the syscon reference, like
> 
> 	rockchip,grf = <&grf 0x154>;
> 
> and then read it from there, to simplify the code needed to get the
> number from the device id.

I would disagree here :-)

Specific to the emac, there also exists a second register in the grf (0xa8 for 
the rk3188) that contains a field 

----
emac_newrcv_en - the selection of RMII receive selection
0: don't support the data package without header
1: support the data package without header
----

which we don't handle currently but somebody might want to in the future.
[There also is no documentation of this at all]


The dt maintainers also generally suggest to define compatibles for the 
individual socs anyway, even if only one is matched, so I don't see the 
necessity to encode this 2 times
	compatible = "rockchip,rk3188-emac", "rockchip,rk3066-emac";
	rockchip,grf = <&grf 0xa4>;

instead of the more flexible
	compatible = "rockchip,rk3188-emac";
	rockchip,grf = <&grf>;

which other rockchip drivers already use in this form.


Heiko
Arnd Bergmann Sept. 3, 2014, 12:50 p.m. UTC | #4
On Wednesday 03 September 2014 14:20:50 Heiko Stübner wrote:
> > 
> > One last question: is this the location given as .grf_offset the
> > only thing in grf that is potentially of concern to this driver?
> > 
> > If it is, you can change the binding to include the register number
> > in the syscon reference, like
> > 
> >       rockchip,grf = <&grf 0x154>;
> > 
> > and then read it from there, to simplify the code needed to get the
> > number from the device id.
> 
> I would disagree here 
> 
> Specific to the emac, there also exists a second register in the grf (0xa8 for 
> the rk3188) that contains a field 
> 
> ----
> emac_newrcv_en - the selection of RMII receive selection
> 0: don't support the data package without header
> 1: support the data package without header
> ----
> 
> which we don't handle currently but somebody might want to in the future.
> [There also is no documentation of this at all]

Ok, fair enough. If there is a chance that there would be more of these
fields that we may want to support in the future, the table approach
seems reasonable.

The main advantage of putting the register number into the syscon
reference is to support future models without driver changes, but
it's not clear if that's worth it.

	Arnd
diff mbox

Patch

diff --git a/drivers/net/ethernet/arc/Kconfig b/drivers/net/ethernet/arc/Kconfig
index 89e04fd..8e262e2 100644
--- a/drivers/net/ethernet/arc/Kconfig
+++ b/drivers/net/ethernet/arc/Kconfig
@@ -32,4 +32,14 @@  config ARC_EMAC
 	  non-standard on-chip ethernet device ARC EMAC 10/100 is used.
 	  Say Y here if you have such a board.  If unsure, say N.
 
+config EMAC_ROCKCHIP
+	tristate "Rockchip EMAC support"
+	select ARC_EMAC_CORE
+	depends on OF_IRQ && OF_NET && REGULATOR
+	---help---
+	  Support for Rockchip RK3066/RK3188 EMAC ethernet controllers.
+	  This selects Rockchip SoC glue layer support for the
+	  emac device driver. This driver is used for RK3066/RK3188
+	  EMAC ethernet controller.
+
 endif # NET_VENDOR_ARC
diff --git a/drivers/net/ethernet/arc/Makefile b/drivers/net/ethernet/arc/Makefile
index 241bb80..79108af 100644
--- a/drivers/net/ethernet/arc/Makefile
+++ b/drivers/net/ethernet/arc/Makefile
@@ -5,3 +5,4 @@ 
 arc_emac-objs := emac_main.o emac_mdio.o
 obj-$(CONFIG_ARC_EMAC_CORE) += arc_emac.o
 obj-$(CONFIG_ARC_EMAC) += emac_arc.o
+obj-$(CONFIG_EMAC_ROCKCHIP) += emac_rockchip.o
diff --git a/drivers/net/ethernet/arc/emac.h b/drivers/net/ethernet/arc/emac.h
index eb2ba67..dae1ac3 100644
--- a/drivers/net/ethernet/arc/emac.h
+++ b/drivers/net/ethernet/arc/emac.h
@@ -123,9 +123,11 @@  struct buffer_state {
  * @speed:	PHY's last set speed.
  */
 struct arc_emac_priv {
-	/* Devices */
 	const char *drv_name;
 	const char *drv_version;
+	void (*set_mac_speed)(void *priv, unsigned int speed);
+
+	/* Devices */
 	struct device *dev;
 	struct phy_device *phy_dev;
 	struct mii_bus *bus;
diff --git a/drivers/net/ethernet/arc/emac_main.c b/drivers/net/ethernet/arc/emac_main.c
index b35c69e..a08f343 100644
--- a/drivers/net/ethernet/arc/emac_main.c
+++ b/drivers/net/ethernet/arc/emac_main.c
@@ -48,6 +48,8 @@  static void arc_emac_adjust_link(struct net_device *ndev)
 	if (priv->speed != phy_dev->speed) {
 		priv->speed = phy_dev->speed;
 		state_changed = 1;
+		if (priv->set_mac_speed)
+			priv->set_mac_speed(priv, priv->speed);
 	}
 
 	if (priv->duplex != phy_dev->duplex) {
diff --git a/drivers/net/ethernet/arc/emac_rockchip.c b/drivers/net/ethernet/arc/emac_rockchip.c
new file mode 100644
index 0000000..97dffbc
--- /dev/null
+++ b/drivers/net/ethernet/arc/emac_rockchip.c
@@ -0,0 +1,228 @@ 
+/**
+ * emac-rockchip.c - Rockchip EMAC specific glue layer
+ *
+ * Copyright (C) 2014 Romain Perier <romain.perier@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of_net.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+
+#include "emac.h"
+
+#define DRV_NAME        "rockchip_emac"
+#define DRV_VERSION     "1.0"
+
+#define GRF_MODE_MII		(1UL << 0)
+#define GRF_MODE_RMII		(0UL << 0)
+#define GRF_SPEED_10M		(0UL << 1)
+#define GRF_SPEED_100M		(1UL << 1)
+#define GRF_SPEED_ENABLE_BIT	(1UL << 17)
+#define GRF_MODE_ENABLE_BIT	(1UL << 16)
+
+struct emac_rockchip_soc_data {
+	int grf_offset;
+};
+
+struct rockchip_priv_data {
+	struct arc_emac_priv emac;
+	struct regmap *grf;
+	const struct emac_rockchip_soc_data *soc_data;
+	struct regulator *regulator;
+	struct clk *refclk;
+};
+
+static const struct emac_rockchip_soc_data emac_rockchip_dt_data[] = {
+	{ .grf_offset = 0x154 }, /* rk3066 */
+	{ .grf_offset = 0x0a4 }, /* rk3188 */
+};
+
+static const struct of_device_id emac_rockchip_dt_ids[] = {
+	{ .compatible = "rockchip,rk3066-emac", .data = &emac_rockchip_dt_data[0] },
+	{ .compatible = "rockchip,rk3188-emac", .data = &emac_rockchip_dt_data[1] },
+	{ /* Sentinel */ }
+};
+
+static void emac_rockchip_set_mac_speed(void *priv, unsigned int speed)
+{
+	struct rockchip_priv_data *emac = priv;
+	u32 data;
+	int err = 0;
+
+	/* write-enable bits */
+	data = GRF_SPEED_ENABLE_BIT;
+
+	switch(speed) {
+	case 10:
+		data |= GRF_SPEED_10M;
+		break;
+	case 100:
+		data |= GRF_SPEED_100M;
+		break;
+	default:
+		pr_err("speed %u not supported\n", speed);
+		return;
+	}
+
+	err = regmap_write(emac->grf, emac->soc_data->grf_offset, data);
+	if (err)
+		pr_err("unable to apply speed %u to grf (%d)\n", speed, err);
+}
+
+static int emac_rockchip_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct net_device *ndev;
+	struct rockchip_priv_data *priv;
+	const struct of_device_id *match;
+	u32 data;
+	int err, interface;
+
+	if (!pdev->dev.of_node)
+		return -ENODEV;
+
+	ndev = alloc_etherdev(sizeof(struct rockchip_priv_data));
+	if (!ndev)
+		return -ENOMEM;
+	platform_set_drvdata(pdev, ndev);
+	SET_NETDEV_DEV(ndev, dev);
+
+	priv = netdev_priv(ndev);
+	priv->emac.drv_name = DRV_NAME;
+	priv->emac.drv_version = DRV_VERSION;
+	priv->emac.set_mac_speed = emac_rockchip_set_mac_speed;
+
+	interface = of_get_phy_mode(dev->of_node);
+
+	/* RK3066 and RK3188 SoCs only support RMII */
+	if (interface != PHY_INTERFACE_MODE_RMII) {
+		dev_err(dev, "unsupported phy interface mode %d\n", interface);
+		err = -ENOTSUPP;
+		goto out_netdev;
+	}
+
+	priv->grf = syscon_regmap_lookup_by_phandle(dev->of_node, "rockchip,grf");
+	if (IS_ERR(priv->grf)) {
+		dev_err(dev, "failed to retrieve global register file from the device tree (%ld)\n", PTR_ERR(priv->grf));
+		err = PTR_ERR(priv->grf);
+		goto out_netdev;
+	}
+
+	match = of_match_node(emac_rockchip_dt_ids, dev->of_node);
+	priv->soc_data = match->data;
+
+	priv->emac.clk = devm_clk_get(dev, "hclk");
+	if (IS_ERR(priv->emac.clk)) {
+		dev_err(dev, "failed to retrieve host clock from device tree (%ld)\n", PTR_ERR(priv->emac.clk));
+		err = PTR_ERR(priv->emac.clk);
+		goto out_netdev;
+	}
+
+	priv->refclk = devm_clk_get(dev, "macref");
+	if (IS_ERR(priv->refclk)) {
+		dev_err(dev, "failed to retrieve reference clock from device tree (%ld)\n", PTR_ERR(priv->refclk));
+		err = PTR_ERR(priv->refclk);
+		goto out_netdev;
+	}
+
+	err = clk_prepare_enable(priv->refclk);
+	if (err) {
+		dev_err(dev, "failed to enable reference clock (%d)\n", err);
+		goto out_netdev;
+	}
+
+	/* Optional regulator for PHY */
+	priv->regulator = devm_regulator_get_optional(dev, "phy");
+	if (IS_ERR(priv->regulator)) {
+		if (PTR_ERR(priv->regulator) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+		dev_err(dev, "no regulator found\n");
+		priv->regulator = NULL;
+	}
+
+	if (priv->regulator) {
+		err = regulator_enable(priv->regulator);
+		if (err) {
+			dev_err(dev, "failed to enable phy-supply (%d)\n", err);
+			goto out_clk_disable;
+		}
+	}
+
+	err = arc_emac_probe(ndev, interface);
+	if (err)
+		goto out_regulator_disable;
+
+	/* write-enable bits */
+	data = GRF_MODE_ENABLE_BIT | GRF_SPEED_ENABLE_BIT;
+
+	data |= GRF_SPEED_100M;
+	data |= GRF_MODE_RMII;
+
+	err = regmap_write(priv->grf, priv->soc_data->grf_offset, data);
+	if (err) {
+		dev_err(dev, "unable to apply initial settings to grf (%d)\n", err);
+		goto out_regulator_disable;
+	}
+
+	/* RMII interface needs always a rate of 50MHz */
+	err = clk_set_rate(priv->refclk, 50000000);
+	if (err)
+		dev_err(dev, "failed to change reference clock rate (%d)\n", err);
+	return 0;
+
+out_regulator_disable:
+	if (priv->regulator)
+		regulator_disable(priv->regulator);
+out_clk_disable:
+	clk_unprepare_disable(priv->refclk);
+out_netdev:
+	free_netdev(ndev);
+	return err;
+}
+
+static int emac_rockchip_remove(struct platform_device *pdev)
+{
+	struct net_device *ndev = platform_get_drvdata(pdev);
+	struct rockchip_priv_data *priv = netdev_priv(ndev);
+	int err;
+
+	clk_disable_unprepare(priv->refclk);
+
+	if (priv->regulator)
+		regulator_disable(priv->regulator);
+
+	err = arc_emac_remove(ndev);
+	free_netdev(ndev);
+	return err;
+}
+
+MODULE_DEVICE_TABLE(of, emac_rockchip_dt_ids);
+
+static struct platform_driver emac_rockchip_driver = {
+	.probe = emac_rockchip_probe,
+	.remove = emac_rockchip_remove,
+	.driver = {
+		.name = DRV_NAME,
+		.of_match_table  = emac_rockchip_dt_ids,
+	},
+};
+
+module_platform_driver(emac_rockchip_driver);
+
+MODULE_AUTHOR("Romain Perier <romain.perier@gmail.com>");
+MODULE_DESCRIPTION("Rockchip EMAC platform driver");
+MODULE_LICENSE("GPL");