[PATCH 1/4] net: ethernet: arc: Probe emac after set RMII clock

[PATCH 1/4] net: ethernet: arc: Probe emac after set RMII clock

[Xing Zheng]

After enter arc_emac_probe, emac will get_phy_id, phy_poll_reset and
other connecting PHY via mdiobus_read, so we need to set correct
ref clock rate for emac before probe emac.

Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
---

 drivers/net/ethernet/arc/emac_rockchip.c |   11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/arc/emac_rockchip.c b/drivers/net/ethernet/arc/emac_rockchip.c
index c31c740..36e9eb1 100644
--- a/drivers/net/ethernet/arc/emac_rockchip.c
+++ b/drivers/net/ethernet/arc/emac_rockchip.c
@@ -164,10 +164,6 @@ static int emac_rockchip_probe(struct platform_device *pdev)
 		}
 	}
 
-	err = arc_emac_probe(ndev, interface);
-	if (err)
-		goto out_regulator_disable;
-
 	/* write-enable bits */
 	data = GRF_MODE_ENABLE_BIT | GRF_SPEED_ENABLE_BIT;
 
@@ -184,6 +180,13 @@ static int emac_rockchip_probe(struct platform_device *pdev)
 	err = clk_set_rate(priv->refclk, 50000000);
 	if (err)
 		dev_err(dev, "failed to change reference clock rate (%d)\n", err);
+
+	err = arc_emac_probe(ndev, interface);
+	if (err) {
+		dev_err(dev, "failed to probe arc emac (%d)\n", err);
+		goto out_regulator_disable;
+	}
+
 	return 0;
 
 out_regulator_disable:
-- 
1.7.9.5

[PATCH 2/4] net: ethernet: arc: Keep emac compatibility for more Rockchip SoCs

[Xing Zheng]

On the RK3066/RK3188, there was fixed GRF offset configuration to set emac
and fixed DIV2 mac TX/RX clock. So, we need to easily set and fit to other
SoCs (RK3036) which maybe have different GRF offset, and need adjust mac
TX/RX clock.

Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
---

 drivers/net/ethernet/arc/emac_rockchip.c |   66 ++++++++++++++++++++----------
 1 file changed, 44 insertions(+), 22 deletions(-)

diff --git a/drivers/net/ethernet/arc/emac_rockchip.c b/drivers/net/ethernet/arc/emac_rockchip.c
index 36e9eb1..d1a9c28 100644
--- a/drivers/net/ethernet/arc/emac_rockchip.c
+++ b/drivers/net/ethernet/arc/emac_rockchip.c
@@ -25,17 +25,13 @@
 #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)
+#define DRV_VERSION     "1.1"
 
 struct emac_rockchip_soc_data {
-	int grf_offset;
+	unsigned int grf_offset;
+	unsigned int grf_mode_offset;
+	unsigned int grf_speed_offset;
+	bool need_div_macclk;
 };
 
 struct rockchip_priv_data {
@@ -44,23 +40,22 @@ struct rockchip_priv_data {
 	const struct emac_rockchip_soc_data *soc_data;
 	struct regulator *regulator;
 	struct clk *refclk;
+	struct clk *macclk;
 };
 
 static void emac_rockchip_set_mac_speed(void *priv, unsigned int speed)
 {
 	struct rockchip_priv_data *emac = priv;
+	u32 speed_offset = emac->soc_data->grf_speed_offset;
 	u32 data;
 	int err = 0;
 
-	/* write-enable bits */
-	data = GRF_SPEED_ENABLE_BIT;
-
 	switch(speed) {
 	case 10:
-		data |= GRF_SPEED_10M;
+		data = (1 << (speed_offset + 16)) | (0 << speed_offset);
 		break;
 	case 100:
-		data |= GRF_SPEED_100M;
+		data = (1 << (speed_offset + 16)) | (1 << speed_offset);
 		break;
 	default:
 		pr_err("speed %u not supported\n", speed);
@@ -73,8 +68,14 @@ static void emac_rockchip_set_mac_speed(void *priv, unsigned int speed)
 }
 
 static const struct emac_rockchip_soc_data emac_rockchip_dt_data[] = {
-	{ .grf_offset = 0x154 }, /* rk3066 */
-	{ .grf_offset = 0x0a4 }, /* rk3188 */
+	{
+	  .grf_offset = 0x154,   .grf_mode_offset = 0,
+	  .grf_speed_offset = 1, .need_div_macclk = 0
+	}, /* rk3066 */
+	{
+	  .grf_offset = 0x0a4,   .grf_mode_offset = 0,
+	  .grf_speed_offset = 1, .need_div_macclk = 0
+	}, /* rk3188 */
 };
 
 static const struct of_device_id emac_rockchip_dt_ids[] = {
@@ -110,7 +111,7 @@ static int emac_rockchip_probe(struct platform_device *pdev)
 
 	interface = of_get_phy_mode(dev->of_node);
 
-	/* RK3066 and RK3188 SoCs only support RMII */
+	/* RK3036/RK3066/RK3188 SoCs only support RMII */
 	if (interface != PHY_INTERFACE_MODE_RMII) {
 		dev_err(dev, "unsupported phy interface mode %d\n", interface);
 		err = -ENOTSUPP;
@@ -164,11 +165,12 @@ static int emac_rockchip_probe(struct platform_device *pdev)
 		}
 	}
 
-	/* write-enable bits */
-	data = GRF_MODE_ENABLE_BIT | GRF_SPEED_ENABLE_BIT;
-
-	data |= GRF_SPEED_100M;
-	data |= GRF_MODE_RMII;
+	/* Set speed 100M */
+	data = (1 << (priv->soc_data->grf_speed_offset + 16)) |
+	       (1 << priv->soc_data->grf_speed_offset);
+	/* Set RMII mode */
+	data |= (1 << (priv->soc_data->grf_mode_offset + 16)) |
+		(0 << priv->soc_data->grf_mode_offset);
 
 	err = regmap_write(priv->grf, priv->soc_data->grf_offset, data);
 	if (err) {
@@ -181,6 +183,26 @@ static int emac_rockchip_probe(struct platform_device *pdev)
 	if (err)
 		dev_err(dev, "failed to change reference clock rate (%d)\n", err);
 
+	if (priv->soc_data->need_div_macclk) {
+		priv->macclk = devm_clk_get(dev, "macclk");
+		if (IS_ERR(priv->macclk)) {
+			dev_err(dev, "failed to retrieve mac clock (%ld)\n", PTR_ERR(priv->macclk));
+			err = PTR_ERR(priv->macclk);
+			goto out_regulator_disable;
+		}
+
+		err = clk_prepare_enable(priv->macclk);
+		if (err) {
+			dev_err(dev, "failed to enable mac clock (%d)\n", err);
+			goto out_regulator_disable;
+		}
+
+		/* RMII TX/RX needs always a rate of 25MHz */
+		err = clk_set_rate(priv->macclk, 25000000);
+		if (err)
+			dev_err(dev, "failed to change mac clock rate (%d)\n", err);
+	}
+
 	err = arc_emac_probe(ndev, interface);
 	if (err) {
 		dev_err(dev, "failed to probe arc emac (%d)\n", err);
-- 
1.7.9.5

[PATCH 3/4] net: ethernet: arc: Add support emac for RK3036

[Xing Zheng]

The RK3036's GRFs offset are different with RK3066/RK3188, and need to set
mac TX/RX clock before probe emac.

Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
---

 drivers/net/ethernet/arc/Kconfig         |    4 ++--
 drivers/net/ethernet/arc/emac_rockchip.c |    9 +++++++--
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/arc/Kconfig b/drivers/net/ethernet/arc/Kconfig
index 52a6b16..6890451 100644
--- a/drivers/net/ethernet/arc/Kconfig
+++ b/drivers/net/ethernet/arc/Kconfig
@@ -34,9 +34,9 @@ config EMAC_ROCKCHIP
 	select ARC_EMAC_CORE
 	depends on OF_IRQ && OF_NET && REGULATOR && HAS_DMA
 	---help---
-	  Support for Rockchip RK3066/RK3188 EMAC ethernet controllers.
+	  Support for Rockchip RK3036/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 device driver. This driver is used for RK3036/RK3066/RK3188
 	  EMAC ethernet controller.
 
 endif # NET_VENDOR_ARC
diff --git a/drivers/net/ethernet/arc/emac_rockchip.c b/drivers/net/ethernet/arc/emac_rockchip.c
index d1a9c28..2433eeb 100644
--- a/drivers/net/ethernet/arc/emac_rockchip.c
+++ b/drivers/net/ethernet/arc/emac_rockchip.c
@@ -69,6 +69,10 @@ static void emac_rockchip_set_mac_speed(void *priv, unsigned int speed)
 
 static const struct emac_rockchip_soc_data emac_rockchip_dt_data[] = {
 	{
+	  .grf_offset = 0x140,   .grf_mode_offset = 8,
+	  .grf_speed_offset = 9, .need_div_macclk = 1
+	}, /* rk3036 */
+	{
 	  .grf_offset = 0x154,   .grf_mode_offset = 0,
 	  .grf_speed_offset = 1, .need_div_macclk = 0
 	}, /* rk3066 */
@@ -79,8 +83,9 @@ static const struct emac_rockchip_soc_data emac_rockchip_dt_data[] = {
 };
 
 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] },
+	{ .compatible = "rockchip,rk3036-emac", .data = &emac_rockchip_dt_data[0] },
+	{ .compatible = "rockchip,rk3066-emac", .data = &emac_rockchip_dt_data[1] },
+	{ .compatible = "rockchip,rk3188-emac", .data = &emac_rockchip_dt_data[2] },
 	{ /* Sentinel */ }
 };
 
-- 
1.7.9.5

[PATCH 4/4] ARM: dts: rockchip: Add support emac for RK3036

[Xing Zheng]

This patch describe the emac, and we need to let mac clock under
the APLL which is able to provide the accurate 50MHz what mac_ref
need.

Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
---

 arch/arm/boot/dts/rk3036-evb.dts   |   25 +++++++++++++++++++++++++
 arch/arm/boot/dts/rk3036-kylin.dts |   23 +++++++++++++++++++++++
 arch/arm/boot/dts/rk3036.dtsi      |   32 ++++++++++++++++++++++++++++++++
 3 files changed, 80 insertions(+)

diff --git a/arch/arm/boot/dts/rk3036-evb.dts b/arch/arm/boot/dts/rk3036-evb.dts
index 28a0336..69b96e6 100644
--- a/arch/arm/boot/dts/rk3036-evb.dts
+++ b/arch/arm/boot/dts/rk3036-evb.dts
@@ -62,3 +62,28 @@
 &uart2 {
 	status = "okay";
 };
+
+&emac {
+	assigned-clocks = <&cru SCLK_MACPLL>;
+	assigned-clock-parents = <&cru PLL_APLL>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&emac_xfer>, <&emac_mdio>, <&rmii_rst>;
+	phy = <&phy0>;
+	status = "okay";
+
+	phy0: ethernet-phy@0 {
+		reg = <0>;
+	};
+};
+
+&pinctrl {
+	pcfg_output_high: pcfg-output-high {
+		output-high;
+	};
+
+	emac {
+		rmii_rst: rmii-rst {
+			rockchip,pins = <2 22 RK_FUNC_GPIO &pcfg_output_high>;
+		};
+	};
+};
diff --git a/arch/arm/boot/dts/rk3036-kylin.dts b/arch/arm/boot/dts/rk3036-kylin.dts
index 992f9ca..3fb1cfe 100644
--- a/arch/arm/boot/dts/rk3036-kylin.dts
+++ b/arch/arm/boot/dts/rk3036-kylin.dts
@@ -285,7 +285,24 @@
 	status = "okay";
 };
 
+&emac {
+	assigned-clocks = <&cru SCLK_MACPLL>;
+	assigned-clock-parents = <&cru PLL_APLL>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&emac_xfer>, <&emac_mdio>, <&rmii_rst>;
+	phy = <&phy0>;
+	status = "okay";
+
+	phy0: ethernet-phy@0 {
+		reg = <0>;
+	};
+};
+
 &pinctrl {
+	pcfg_output_high: pcfg-output-high {
+		output-high;
+	};
+
 	pmic {
 		pmic_int: pmic-int {
 			rockchip,pins = <2 2 RK_FUNC_GPIO &pcfg_pull_default>;
@@ -297,4 +314,10 @@
 			rockchip,pins = <2 7 RK_FUNC_1 &pcfg_pull_none>;
 		};
 	};
+
+	emac {
+		rmii_rst: rmii-rst {
+			rockchip,pins = <2 22 RK_FUNC_GPIO &pcfg_output_high>;
+		};
+	};
 };
diff --git a/arch/arm/boot/dts/rk3036.dtsi b/arch/arm/boot/dts/rk3036.dtsi
index b9567c1..0c09fb3 100644
--- a/arch/arm/boot/dts/rk3036.dtsi
+++ b/arch/arm/boot/dts/rk3036.dtsi
@@ -186,6 +186,20 @@
 		status = "disabled";
 	};
 
+	emac: ethernet@10200000 {
+		compatible = "rockchip,rk3036-emac", "snps,arc-emac";
+		reg = <0x10200000 0x4000>;
+		interrupts = <GIC_SPI 8 IRQ_TYPE_LEVEL_HIGH>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		rockchip,grf = <&grf>;
+		clocks = <&cru HCLK_MAC>, <&cru SCLK_MACREF>, <&cru SCLK_MAC>;
+		clock-names = "hclk", "macref", "macclk";
+		max-speed = <100>;
+		phy-mode = "rmii";
+		status = "disabled";
+	};
+
 	sdmmc: dwmmc@10214000 {
 		compatible = "rockchip,rk3036-dw-mshc", "rockchip,rk3288-dw-mshc";
 		reg = <0x10214000 0x4000>;
@@ -556,6 +570,24 @@
 			};
 		};
 
+		emac {
+			emac_xfer: emac-xfer {
+				rockchip,pins = <2 10 RK_FUNC_1 &pcfg_pull_none>, /* crs_dvalid */
+						<2 13 RK_FUNC_1 &pcfg_pull_none>, /* tx_en */
+						<2 14 RK_FUNC_1 &pcfg_pull_none>, /* mac_clk */
+						<2 15 RK_FUNC_1 &pcfg_pull_none>, /* rx_err */
+						<2 16 RK_FUNC_1 &pcfg_pull_none>, /* rxd1 */
+						<2 17 RK_FUNC_1 &pcfg_pull_none>, /* rxd0 */
+						<2 18 RK_FUNC_1 &pcfg_pull_none>, /* txd1 */
+						<2 19 RK_FUNC_1 &pcfg_pull_none>; /* txd0 */
+			};
+
+			emac_mdio: emac-mdio {
+				rockchip,pins = <2 12 RK_FUNC_1 &pcfg_pull_none>, /* mac_md */
+						<2 25 RK_FUNC_1 &pcfg_pull_none>; /* mac_mdclk */
+			};
+		};
+
 		i2c0 {
 			i2c0_xfer: i2c0-xfer {
 				rockchip,pins = <0 0 RK_FUNC_1 &pcfg_pull_none>,
-- 
1.7.9.5

Re: [PATCH 4/4] ARM: dts: rockchip: Add support emac for RK3036

[kbuild test robot]

[-- Attachment #1: Type: text/plain, Size: 941 bytes --]

Hi Xing,

[auto build test ERROR on rockchip/for-next]
[also build test ERROR on next-20151223]
[cannot apply to v4.4-rc6]

url:    https://github.com/0day-ci/linux/commits/Xing-Zheng/net-ethernet-arc-Probe-emac-after-set-RMII-clock/20151223-172442
base:   https://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip.git for-next
config: arm-allmodconfig (attached as .config)
reproduce:
        wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=arm 

All errors (new ones prefixed by >>):

>> Error: arch/arm/boot/dts/rk3036.dtsi:196.18-19 syntax error
   FATAL ERROR: Unable to parse input tree

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/octet-stream, Size: 54588 bytes --]

Re: [PATCH 4/4] ARM: dts: rockchip: Add support emac for RK3036

[Caesar Wang]

Hi Xing,

在 2015年12月23日 17:19, Xing Zheng 写道:
> This patch describe the emac, and we need to let mac clock under
> the APLL which is able to provide the accurate 50MHz what mac_ref
> need.
>
> Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
> ---
>
>   arch/arm/boot/dts/rk3036-evb.dts   |   25 +++++++++++++++++++++++++
>   arch/arm/boot/dts/rk3036-kylin.dts |   23 +++++++++++++++++++++++
>   arch/arm/boot/dts/rk3036.dtsi      |   32 ++++++++++++++++++++++++++++++++
>   3 files changed, 80 insertions(+)
>
> diff --git a/arch/arm/boot/dts/rk3036-evb.dts b/arch/arm/boot/dts/rk3036-evb.dts
> index 28a0336..69b96e6 100644
> --- a/arch/arm/boot/dts/rk3036-evb.dts
> +++ b/arch/arm/boot/dts/rk3036-evb.dts
> @@ -62,3 +62,28 @@
>   &uart2 {
>   	status = "okay";
>   };
> +
> +&emac {
> +	assigned-clocks = <&cru SCLK_MACPLL>;
> +	assigned-clock-parents = <&cru PLL_APLL>;
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&emac_xfer>, <&emac_mdio>, <&rmii_rst>;
> +	phy = <&phy0>;
> +	status = "okay";
> +
> +	phy0: ethernet-phy@0 {
> +		reg = <0>;
> +	};
> +};
> +
> +&pinctrl {
> +	pcfg_output_high: pcfg-output-high {
> +		output-high;
> +	};
> +

That's seem a new preperty for pinctrl on rk3036, we should submit it in 
rk3036 dtsi.

Do we are really need it?

GPIO2_C6 is pulled up in internal chip.
So, maybe you only do that:

rockchip,pins = <2 22 RK_FUNC_GPIO &pcfg_pull_default>;


> +	emac {
> +		rmii_rst: rmii-rst {
> +			rockchip,pins = <2 22 RK_FUNC_GPIO &pcfg_output_high>;
> +		};
> +	};
> +};
> diff --git a/arch/arm/boot/dts/rk3036-kylin.dts b/arch/arm/boot/dts/rk3036-kylin.dts
> index 992f9ca..3fb1cfe 100644
> --- a/arch/arm/boot/dts/rk3036-kylin.dts
> +++ b/arch/arm/boot/dts/rk3036-kylin.dts
> @@ -285,7 +285,24 @@
>   	status = "okay";
>   };
>   
> +&emac {
> +	assigned-clocks = <&cru SCLK_MACPLL>;
> +	assigned-clock-parents = <&cru PLL_APLL>;
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&emac_xfer>, <&emac_mdio>, <&rmii_rst>;
> +	phy = <&phy0>;
> +	status = "okay";
> +
> +	phy0: ethernet-phy@0 {
> +		reg = <0>;
> +	};
> +};
> +
>   &pinctrl {
> +	pcfg_output_high: pcfg-output-high {
> +		output-high;
> +	};
> +
>   	pmic {
>   		pmic_int: pmic-int {
>   			rockchip,pins = <2 2 RK_FUNC_GPIO &pcfg_pull_default>;
> @@ -297,4 +314,10 @@
>   			rockchip,pins = <2 7 RK_FUNC_1 &pcfg_pull_none>;
>   		};
>   	};
> +
> +	emac {
> +		rmii_rst: rmii-rst {
> +			rockchip,pins = <2 22 RK_FUNC_GPIO &pcfg_output_high>;
> +		};
> +	};
>   };
> diff --git a/arch/arm/boot/dts/rk3036.dtsi b/arch/arm/boot/dts/rk3036.dtsi
> index b9567c1..0c09fb3 100644
> --- a/arch/arm/boot/dts/rk3036.dtsi
> +++ b/arch/arm/boot/dts/rk3036.dtsi
> @@ -186,6 +186,20 @@
>   		status = "disabled";
>   	};
>   
> +	emac: ethernet@10200000 {
> +		compatible = "rockchip,rk3036-emac", "snps,arc-emac";
> +		reg = <0x10200000 0x4000>;
> +		interrupts = <GIC_SPI 8 IRQ_TYPE_LEVEL_HIGH>;
> +		#address-cells = <1>;
> +		#size-cells = <0>;
> +		rockchip,grf = <&grf>;
> +		clocks = <&cru HCLK_MAC>, <&cru SCLK_MACREF>, <&cru SCLK_MAC>;
> +		clock-names = "hclk", "macref", "macclk";
> +		max-speed = <100>;
> +		phy-mode = "rmii";
> +		status = "disabled";
> +	};
> +
>   	sdmmc: dwmmc@10214000 {
>   		compatible = "rockchip,rk3036-dw-mshc", "rockchip,rk3288-dw-mshc";
>   		reg = <0x10214000 0x4000>;
> @@ -556,6 +570,24 @@
>   			};
>   		};
>   
> +		emac {
> +			emac_xfer: emac-xfer {
> +				rockchip,pins = <2 10 RK_FUNC_1 &pcfg_pull_none>, /* crs_dvalid */
> +						<2 13 RK_FUNC_1 &pcfg_pull_none>, /* tx_en */
> +						<2 14 RK_FUNC_1 &pcfg_pull_none>, /* mac_clk */
> +						<2 15 RK_FUNC_1 &pcfg_pull_none>, /* rx_err */
> +						<2 16 RK_FUNC_1 &pcfg_pull_none>, /* rxd1 */
> +						<2 17 RK_FUNC_1 &pcfg_pull_none>, /* rxd0 */
> +						<2 18 RK_FUNC_1 &pcfg_pull_none>, /* txd1 */
> +						<2 19 RK_FUNC_1 &pcfg_pull_none>; /* txd0 */
> +			};
> +
> +			emac_mdio: emac-mdio {
> +				rockchip,pins = <2 12 RK_FUNC_1 &pcfg_pull_none>, /* mac_md */
> +						<2 25 RK_FUNC_1 &pcfg_pull_none>; /* mac_mdclk */
> +			};
> +		};
> +
>   		i2c0 {
>   			i2c0_xfer: i2c0-xfer {
>   				rockchip,pins = <0 0 RK_FUNC_1 &pcfg_pull_none>,


-- 
Thanks,
Caesar

Re: [PATCH 1/4] net: ethernet: arc: Probe emac after set RMII clock

[David Miller]

I only see 3 patches in this series.

Furthermore, you failed to provide a proper "[PATCH 0/4] xxx" posting
providing a high level description of what this series is doing, and
how it is doing it, and why.

Thanks.

Re: [PATCH 1/4] net: ethernet: arc: Probe emac after set RMII clock

[Xing Zheng]

Hi David,
Sorry, I missed the cover letter.
I have added it and resent the patchset.

Thanks.

- Xing Zheng

On 2015年12月28日 13:14, David Miller wrote:
> I only see 3 patches in this series.
>
> Furthermore, you failed to provide a proper "[PATCH 0/4] xxx" posting
> providing a high level description of what this series is doing, and
> how it is doing it, and why.
>
> Thanks.
>
>
>