diff mbox series

[1/3] net: mdio-ipq4019: Add mdio reset function

Message ID 20210729125358.5227-1-luoj@codeaurora.org
State New
Headers show
Series [1/3] net: mdio-ipq4019: Add mdio reset function | expand

Commit Message

Jie Luo July 29, 2021, 12:53 p.m. UTC
Support PHY reset function and MDIO clock frequency configuration.

Signed-off-by: Luo Jie <luoj@codeaurora.org>
---
 drivers/net/mdio/Kconfig        |  1 +
 drivers/net/mdio/mdio-ipq4019.c | 71 +++++++++++++++++++++++++++++++++
 2 files changed, 72 insertions(+)

Comments

Andrew Lunn July 29, 2021, 1:26 p.m. UTC | #1
Hi Luo

For a patchset, netdev wants to see a patch 0/X which describes the
big picture. What is the patchset as a whole doing.

> +static int ipq_mdio_reset(struct mii_bus *bus)
> +{
> +	struct ipq4019_mdio_data *priv = bus->priv;
> +	struct device *dev = bus->parent;
> +	struct gpio_desc *reset_gpio;
> +	u32 val;
> +	int i, ret;
> +
> +	/* To indicate CMN_PLL that ethernet_ldo has been ready if needed */
> +	if (!IS_ERR(priv->eth_ldo_rdy)) {
> +		val = readl(priv->eth_ldo_rdy);
> +		val |= BIT(0);
> +		writel(val, priv->eth_ldo_rdy);
> +		fsleep(QCA_PHY_SET_DELAY_US);
> +	}
> +
> +	/* Reset GEPHY if need */
> +	if (!IS_ERR(priv->reset_ctrl)) {
> +		reset_control_assert(priv->reset_ctrl);
> +		fsleep(QCA_PHY_SET_DELAY_US);
> +		reset_control_deassert(priv->reset_ctrl);
> +		fsleep(QCA_PHY_SET_DELAY_US);
> +	}

What exactly is being reset here? Which is GEPHY?

The MDIO bus master driver should not be touching any Ethernet
PHYs. All it provides is a bus, nothing more.

> +
> +	/* Configure MDIO clock frequency */
> +	if (!IS_ERR(priv->mdio_clk)) {
> +		ret = clk_set_rate(priv->mdio_clk, QCA_MDIO_CLK_RATE);
> +		if (ret)
> +			return ret;
> +
> +		ret = clk_prepare_enable(priv->mdio_clk);
> +		if (ret)
> +			return ret;
> +	}

> +
> +	/* Reset PHYs by gpio pins */
> +	for (i = 0; i < gpiod_count(dev, "phy-reset"); i++) {
> +		reset_gpio = gpiod_get_index_optional(dev, "phy-reset", i, GPIOD_OUT_HIGH);
> +		if (IS_ERR(reset_gpio))
> +			continue;
> +		gpiod_set_value_cansleep(reset_gpio, 0);
> +		fsleep(QCA_PHY_SET_DELAY_US);
> +		gpiod_set_value_cansleep(reset_gpio, 1);
> +		fsleep(QCA_PHY_SET_DELAY_US);
> +		gpiod_put(reset_gpio);
> +	}

No, there is common code in phylib to do that.

>  static int ipq4019_mdio_probe(struct platform_device *pdev)
>  {
>  	struct ipq4019_mdio_data *priv;
>  	struct mii_bus *bus;
> +	struct resource *res;
>  	int ret;
>  
>  	bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*priv));
> @@ -182,14 +244,23 @@ static int ipq4019_mdio_probe(struct platform_device *pdev)
>  		return -ENOMEM;
>  
>  	priv = bus->priv;
> +	priv->eth_ldo_rdy = IOMEM_ERR_PTR(-EINVAL);
>  
>  	priv->membase = devm_platform_ioremap_resource(pdev, 0);
>  	if (IS_ERR(priv->membase))
>  		return PTR_ERR(priv->membase);
>  
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> +	if (res)
> +		priv->eth_ldo_rdy = devm_ioremap_resource(&pdev->dev, res);
> +
> +	priv->reset_ctrl = devm_reset_control_get_exclusive(&pdev->dev, "gephy_mdc_rst");
> +	priv->mdio_clk = devm_clk_get(&pdev->dev, "gcc_mdio_ahb_clk");

You probably want to use devm_clk_get_optional().

    Andrew
Jie Luo Aug. 2, 2021, 5:56 a.m. UTC | #2
On 2021-07-29 21:15, Andrew Lunn wrote:
> On Thu, Jul 29, 2021 at 08:53:57PM +0800, Luo Jie wrote:

>> mdio_ipq driver supports more SOCs such as ipq40xx, ipq807x,

>> ipq60xx and ipq50xx.

>> 

>> Signed-off-by: Luo Jie <luoj@codeaurora.org>

>> ---

>>  drivers/net/mdio/Kconfig                      |  6 +-

>>  drivers/net/mdio/Makefile                     |  2 +-

>>  .../net/mdio/{mdio-ipq4019.c => mdio-ipq.c}   | 66 

>> +++++++++----------

>>  3 files changed, 37 insertions(+), 37 deletions(-)

>>  rename drivers/net/mdio/{mdio-ipq4019.c => mdio-ipq.c} (81%)

> 

> Hi Luo

> 

> We don't rename files unless there is a very good reason. It makes

> back porting of fixes harder in stable. There are plenty of examples

> of files with device specific names, but supporting a broad range of

> devices. Take for example lm75, at24.

> 

> Hi Andrew

> Thanks for the comments, will update the patch set to keep the name 

> unchanged.

> 

>> -config MDIO_IPQ4019

>> -	tristate "Qualcomm IPQ4019 MDIO interface support"

>> +config MDIO_IPQ

>> +	tristate "Qualcomm IPQ MDIO interface support"

>>  	depends on HAS_IOMEM && OF_MDIO

>>  	depends on GPIOLIB && COMMON_CLK && RESET_CONTROLLER

>>  	help

>>  	  This driver supports the MDIO interface found in Qualcomm

>> -	  IPQ40xx series Soc-s.

>> +	  IPQ40xx, IPQ60XX, IPQ807X and IPQ50XX series Soc-s.

> 

> Please leave the MDIO_IPQ4019 unchanged, so we don't break backwards

> compatibility, but the changes to the text are O.K.

> 

> will correct it in the next patch set.

> 

>> @@ -31,38 +31,38 @@

>>  /* 0 = Clause 22, 1 = Clause 45 */

>>  #define MDIO_MODE_C45				BIT(8)

>> 

>> -#define IPQ4019_MDIO_TIMEOUT	10000

>> -#define IPQ4019_MDIO_SLEEP		10

>> +#define IPQ_MDIO_TIMEOUT	10000

>> +#define IPQ_MDIO_SLEEP		10

> 

> This sort of mass rename will also make back porting fixes

> harder. Please don't do it.

> 

> will keep it unchanged in the next patch set.

> 

>> -static const struct of_device_id ipq4019_mdio_dt_ids[] = {

>> +static const struct of_device_id ipq_mdio_dt_ids[] = {

>>  	{ .compatible = "qcom,ipq4019-mdio" },

>> +	{ .compatible = "qcom,ipq-mdio" },

>>  	{ }

>>  };

> 

> Such a generic name is not a good idea. It appears this driver is not

> compatible with the IPQ8064? It is O.K. to add more specific

> compatibles. So you could add

> 

> qcom,ipq40xx, qcom,ipq60xx, qcom,ipq807x and qcom,ipq50xx.

> 

> But really, there is no need. Take for example snps,dwmac-mdio, which

> is used in all sorts of devices.

> 

>    Andrew


> Hi Andrew, yes, this driver is not compatible with IPQ8064, but it is 

> compatible with

> the new chipset such as ipq807x, ipq60xx and ipq50xx, will take your 

> suggestion in

> the next patch set, thanks for the comments.

>
Jie Luo Aug. 2, 2021, 6:46 a.m. UTC | #3
On 2021-07-29 21:26, Andrew Lunn wrote:
> Hi Luo

> 

> For a patchset, netdev wants to see a patch 0/X which describes the

> big picture. What is the patchset as a whole doing.

> 

> Hi Andrew,

> Thanks for reminder, will provide it in the next patch set.

> 

>> +static int ipq_mdio_reset(struct mii_bus *bus)

>> +{

>> +	struct ipq4019_mdio_data *priv = bus->priv;

>> +	struct device *dev = bus->parent;

>> +	struct gpio_desc *reset_gpio;

>> +	u32 val;

>> +	int i, ret;

>> +

>> +	/* To indicate CMN_PLL that ethernet_ldo has been ready if needed */

>> +	if (!IS_ERR(priv->eth_ldo_rdy)) {

>> +		val = readl(priv->eth_ldo_rdy);

>> +		val |= BIT(0);

>> +		writel(val, priv->eth_ldo_rdy);

>> +		fsleep(QCA_PHY_SET_DELAY_US);

>> +	}

>> +

>> +	/* Reset GEPHY if need */

>> +	if (!IS_ERR(priv->reset_ctrl)) {

>> +		reset_control_assert(priv->reset_ctrl);

>> +		fsleep(QCA_PHY_SET_DELAY_US);

>> +		reset_control_deassert(priv->reset_ctrl);

>> +		fsleep(QCA_PHY_SET_DELAY_US);

>> +	}

> 

> What exactly is being reset here? Which is GEPHY?

> 

> The MDIO bus master driver should not be touching any Ethernet

> PHYs. All it provides is a bus, nothing more.

> 

> The GEPHY is the embedded Giga Ethernet PHY in the chipset IPQ50xx, 

> there is a dedicated MDIO bus for this internal PHY.

> what the reset function does here is for resetting this dedicated MDIO 

> bus and this embedded PHY DSP hardware.

> because this dedicated MDIO bus is only connected with this internal 

> PHY on chip set IPQ50xx, so i put this

> code in the MDIO reset function.

> 

>> +

>> +	/* Configure MDIO clock frequency */

>> +	if (!IS_ERR(priv->mdio_clk)) {

>> +		ret = clk_set_rate(priv->mdio_clk, QCA_MDIO_CLK_RATE);

>> +		if (ret)

>> +			return ret;

>> +

>> +		ret = clk_prepare_enable(priv->mdio_clk);

>> +		if (ret)

>> +			return ret;

>> +	}

> 

>> +

>> +	/* Reset PHYs by gpio pins */

>> +	for (i = 0; i < gpiod_count(dev, "phy-reset"); i++) {

>> +		reset_gpio = gpiod_get_index_optional(dev, "phy-reset", i, 

>> GPIOD_OUT_HIGH);

>> +		if (IS_ERR(reset_gpio))

>> +			continue;

>> +		gpiod_set_value_cansleep(reset_gpio, 0);

>> +		fsleep(QCA_PHY_SET_DELAY_US);

>> +		gpiod_set_value_cansleep(reset_gpio, 1);

>> +		fsleep(QCA_PHY_SET_DELAY_US);

>> +		gpiod_put(reset_gpio);

>> +	}

> 

> No, there is common code in phylib to do that.

> 

> Hi Andrew,

> The common code in phylib for resetting PHY by GPIO pin is high active, 

> which is not suitable for the PHY reset here.

> for resetting the PHY, calling gpiod_set_value_cansleep(reset_gpio, 1), 

> then gpiod_set_value_cansleep(reset_gpio, 0).

> but as for resetting the PHY by GPIO pin in IPQ chipset, this is the 

> opposite process(low active) from the phylib code,

> which needs to set the GPIO output value to 0, then to 1 for reset as 

> the code above.

> 

>>  static int ipq4019_mdio_probe(struct platform_device *pdev)

>>  {

>>  	struct ipq4019_mdio_data *priv;

>>  	struct mii_bus *bus;

>> +	struct resource *res;

>>  	int ret;

>> 

>>  	bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*priv));

>> @@ -182,14 +244,23 @@ static int ipq4019_mdio_probe(struct 

>> platform_device *pdev)

>>  		return -ENOMEM;

>> 

>>  	priv = bus->priv;

>> +	priv->eth_ldo_rdy = IOMEM_ERR_PTR(-EINVAL);

>> 

>>  	priv->membase = devm_platform_ioremap_resource(pdev, 0);

>>  	if (IS_ERR(priv->membase))

>>  		return PTR_ERR(priv->membase);

>> 

>> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);

>> +	if (res)

>> +		priv->eth_ldo_rdy = devm_ioremap_resource(&pdev->dev, res);

>> +

>> +	priv->reset_ctrl = devm_reset_control_get_exclusive(&pdev->dev, 

>> "gephy_mdc_rst");

>> +	priv->mdio_clk = devm_clk_get(&pdev->dev, "gcc_mdio_ahb_clk");

> 

> You probably want to use devm_clk_get_optional().

> 

>     Andrew

> 

> thanks for the comment, will update it in the next patch set.
diff mbox series

Patch

diff --git a/drivers/net/mdio/Kconfig b/drivers/net/mdio/Kconfig
index 99a6c13a11af..06a605ffb950 100644
--- a/drivers/net/mdio/Kconfig
+++ b/drivers/net/mdio/Kconfig
@@ -169,6 +169,7 @@  config MDIO_OCTEON
 config MDIO_IPQ4019
 	tristate "Qualcomm IPQ4019 MDIO interface support"
 	depends on HAS_IOMEM && OF_MDIO
+	depends on GPIOLIB && COMMON_CLK && RESET_CONTROLLER
 	help
 	  This driver supports the MDIO interface found in Qualcomm
 	  IPQ40xx series Soc-s.
diff --git a/drivers/net/mdio/mdio-ipq4019.c b/drivers/net/mdio/mdio-ipq4019.c
index 9cd71d896963..01f5b9393537 100644
--- a/drivers/net/mdio/mdio-ipq4019.c
+++ b/drivers/net/mdio/mdio-ipq4019.c
@@ -11,6 +11,9 @@ 
 #include <linux/of_mdio.h>
 #include <linux/phy.h>
 #include <linux/platform_device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/reset.h>
+#include <linux/clk.h>
 
 #define MDIO_MODE_REG				0x40
 #define MDIO_ADDR_REG				0x44
@@ -31,8 +34,16 @@ 
 #define IPQ4019_MDIO_TIMEOUT	10000
 #define IPQ4019_MDIO_SLEEP		10
 
+/* MDIO clock source frequency is fixed to 100M */
+#define QCA_MDIO_CLK_RATE	100000000
+
+#define QCA_PHY_SET_DELAY_US	100000
+
 struct ipq4019_mdio_data {
 	void __iomem	*membase;
+	void __iomem *eth_ldo_rdy;
+	struct reset_control *reset_ctrl;
+	struct clk *mdio_clk;
 };
 
 static int ipq4019_mdio_wait_busy(struct mii_bus *bus)
@@ -171,10 +182,61 @@  static int ipq4019_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
 	return 0;
 }
 
+static int ipq_mdio_reset(struct mii_bus *bus)
+{
+	struct ipq4019_mdio_data *priv = bus->priv;
+	struct device *dev = bus->parent;
+	struct gpio_desc *reset_gpio;
+	u32 val;
+	int i, ret;
+
+	/* To indicate CMN_PLL that ethernet_ldo has been ready if needed */
+	if (!IS_ERR(priv->eth_ldo_rdy)) {
+		val = readl(priv->eth_ldo_rdy);
+		val |= BIT(0);
+		writel(val, priv->eth_ldo_rdy);
+		fsleep(QCA_PHY_SET_DELAY_US);
+	}
+
+	/* Reset GEPHY if need */
+	if (!IS_ERR(priv->reset_ctrl)) {
+		reset_control_assert(priv->reset_ctrl);
+		fsleep(QCA_PHY_SET_DELAY_US);
+		reset_control_deassert(priv->reset_ctrl);
+		fsleep(QCA_PHY_SET_DELAY_US);
+	}
+
+	/* Configure MDIO clock frequency */
+	if (!IS_ERR(priv->mdio_clk)) {
+		ret = clk_set_rate(priv->mdio_clk, QCA_MDIO_CLK_RATE);
+		if (ret)
+			return ret;
+
+		ret = clk_prepare_enable(priv->mdio_clk);
+		if (ret)
+			return ret;
+	}
+
+	/* Reset PHYs by gpio pins */
+	for (i = 0; i < gpiod_count(dev, "phy-reset"); i++) {
+		reset_gpio = gpiod_get_index_optional(dev, "phy-reset", i, GPIOD_OUT_HIGH);
+		if (IS_ERR(reset_gpio))
+			continue;
+		gpiod_set_value_cansleep(reset_gpio, 0);
+		fsleep(QCA_PHY_SET_DELAY_US);
+		gpiod_set_value_cansleep(reset_gpio, 1);
+		fsleep(QCA_PHY_SET_DELAY_US);
+		gpiod_put(reset_gpio);
+	}
+
+	return 0;
+}
+
 static int ipq4019_mdio_probe(struct platform_device *pdev)
 {
 	struct ipq4019_mdio_data *priv;
 	struct mii_bus *bus;
+	struct resource *res;
 	int ret;
 
 	bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*priv));
@@ -182,14 +244,23 @@  static int ipq4019_mdio_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	priv = bus->priv;
+	priv->eth_ldo_rdy = IOMEM_ERR_PTR(-EINVAL);
 
 	priv->membase = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(priv->membase))
 		return PTR_ERR(priv->membase);
 
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (res)
+		priv->eth_ldo_rdy = devm_ioremap_resource(&pdev->dev, res);
+
+	priv->reset_ctrl = devm_reset_control_get_exclusive(&pdev->dev, "gephy_mdc_rst");
+	priv->mdio_clk = devm_clk_get(&pdev->dev, "gcc_mdio_ahb_clk");
+
 	bus->name = "ipq4019_mdio";
 	bus->read = ipq4019_mdio_read;
 	bus->write = ipq4019_mdio_write;
+	bus->reset = ipq_mdio_reset;
 	bus->parent = &pdev->dev;
 	snprintf(bus->id, MII_BUS_ID_SIZE, "%s%d", pdev->name, pdev->id);