2020-03-25 15:07:18

by Philippe Schenker

[permalink] [raw]
Subject: [PATCH 1/2] net: phy: micrel.c: add rgmii interface delay possibility to ksz9131

The KSZ9131 provides DLL controlled delays on RXC and TXC lines. This
patch makes use of those delays. The information which delays should
be enabled or disabled comes from the interface names, documented in
ethernet-controller.yaml:

rgmii: Disable RXC and TXC delays
rgmii-id: Enable RXC and TXC delays
rgmii-txid: Enable only TXC delay, disable RXC delay
rgmii-rxid: Enable onlx RXC delay, disable TXC delay

Signed-off-by: Philippe Schenker <[email protected]>
---

drivers/net/phy/micrel.c | 45 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 45 insertions(+)

diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
index 63dedec0433d..d3ad09774847 100644
--- a/drivers/net/phy/micrel.c
+++ b/drivers/net/phy/micrel.c
@@ -704,6 +704,48 @@ static int ksz9131_of_load_skew_values(struct phy_device *phydev,
return phy_write_mmd(phydev, 2, reg, newval);
}

+/* MMD Address 0x2 */
+#define KSZ9131RN_RXC_DLL_CTRL 76
+#define KSZ9131RN_TXC_DLL_CTRL 77
+#define KSZ9131RN_DLL_CTRL_BYPASS BIT_MASK(12)
+#define KSZ9131RN_DLL_ENABLE_DELAY 0
+#define KSZ9131RN_DLL_DISABLE_DELAY BIT(12)
+
+static int ksz9131_config_rgmii_delay(struct phy_device *phydev)
+{
+ int ret;
+ u16 rxcdll_val, txcdll_val;
+
+ switch (phydev->interface) {
+ case PHY_INTERFACE_MODE_RGMII:
+ rxcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
+ txcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
+ break;
+ case PHY_INTERFACE_MODE_RGMII_ID:
+ rxcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
+ txcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
+ break;
+ case PHY_INTERFACE_MODE_RGMII_RXID:
+ rxcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
+ txcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
+ break;
+ case PHY_INTERFACE_MODE_RGMII_TXID:
+ rxcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
+ txcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
+ break;
+ default:
+ return 0;
+ }
+
+ ret = phy_modify_mmd_changed(phydev, 2, KSZ9131RN_RXC_DLL_CTRL,
+ KSZ9131RN_DLL_CTRL_BYPASS, rxcdll_val);
+ if (ret < 0)
+ return ret;
+
+ return phy_modify_mmd_changed(phydev, 2, KSZ9131RN_TXC_DLL_CTRL,
+ KSZ9131RN_DLL_CTRL_BYPASS, txcdll_val);
+}
+
static int ksz9131_config_init(struct phy_device *phydev)
{
const struct device *dev = &phydev->mdio.dev;
@@ -730,6 +772,9 @@ static int ksz9131_config_init(struct phy_device *phydev)
if (!of_node)
return 0;

+ if (phy_interface_is_rgmii(phydev))
+ ksz9131_config_rgmii_delay(phydev);
+
ret = ksz9131_of_load_skew_values(phydev, of_node,
MII_KSZ9031RN_CLK_PAD_SKEW, 5,
clk_skews, 2);
--
2.26.0


2020-03-25 15:24:45

by Heiner Kallweit

[permalink] [raw]
Subject: Re: [PATCH 1/2] net: phy: micrel.c: add rgmii interface delay possibility to ksz9131

On 25.03.2020 16:03, Philippe Schenker wrote:
> The KSZ9131 provides DLL controlled delays on RXC and TXC lines. This
> patch makes use of those delays. The information which delays should
> be enabled or disabled comes from the interface names, documented in
> ethernet-controller.yaml:
>
> rgmii: Disable RXC and TXC delays
> rgmii-id: Enable RXC and TXC delays
> rgmii-txid: Enable only TXC delay, disable RXC delay
> rgmii-rxid: Enable onlx RXC delay, disable TXC delay
>
> Signed-off-by: Philippe Schenker <[email protected]>
> ---
>
> drivers/net/phy/micrel.c | 45 ++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 45 insertions(+)
>
> diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
> index 63dedec0433d..d3ad09774847 100644
> --- a/drivers/net/phy/micrel.c
> +++ b/drivers/net/phy/micrel.c
> @@ -704,6 +704,48 @@ static int ksz9131_of_load_skew_values(struct phy_device *phydev,
> return phy_write_mmd(phydev, 2, reg, newval);
> }
>
> +/* MMD Address 0x2 */
> +#define KSZ9131RN_RXC_DLL_CTRL 76
> +#define KSZ9131RN_TXC_DLL_CTRL 77
> +#define KSZ9131RN_DLL_CTRL_BYPASS BIT_MASK(12)
> +#define KSZ9131RN_DLL_ENABLE_DELAY 0
> +#define KSZ9131RN_DLL_DISABLE_DELAY BIT(12)
> +
> +static int ksz9131_config_rgmii_delay(struct phy_device *phydev)
> +{
> + int ret;
> + u16 rxcdll_val, txcdll_val;
> +

Reverse xmas tree order please.

> + switch (phydev->interface) {
> + case PHY_INTERFACE_MODE_RGMII:
> + rxcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
> + txcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
> + break;
> + case PHY_INTERFACE_MODE_RGMII_ID:
> + rxcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
> + txcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
> + break;
> + case PHY_INTERFACE_MODE_RGMII_RXID:
> + rxcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
> + txcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
> + break;
> + case PHY_INTERFACE_MODE_RGMII_TXID:
> + rxcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
> + txcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
> + break;
> + default:
> + return 0;
> + }
> +
> + ret = phy_modify_mmd_changed(phydev, 2, KSZ9131RN_RXC_DLL_CTRL,
> + KSZ9131RN_DLL_CTRL_BYPASS, rxcdll_val);
> + if (ret < 0)
> + return ret;
> +
> + return phy_modify_mmd_changed(phydev, 2, KSZ9131RN_TXC_DLL_CTRL,
> + KSZ9131RN_DLL_CTRL_BYPASS, txcdll_val);

phy_modify_mmd_changed() returns 1 if the register value was changed,
and that's not what you want here. Simply use phy_modify_mmd() in both
occurrences. And your function has a return value, but it's not used by
the caller.

> +}
> +
> static int ksz9131_config_init(struct phy_device *phydev)
> {
> const struct device *dev = &phydev->mdio.dev;
> @@ -730,6 +772,9 @@ static int ksz9131_config_init(struct phy_device *phydev)
> if (!of_node)
> return 0;
>
> + if (phy_interface_is_rgmii(phydev))
> + ksz9131_config_rgmii_delay(phydev);
> +
> ret = ksz9131_of_load_skew_values(phydev, of_node,
> MII_KSZ9031RN_CLK_PAD_SKEW, 5,
> clk_skews, 2);
>

2020-03-25 15:29:21

by Heiner Kallweit

[permalink] [raw]
Subject: Re: [PATCH 1/2] net: phy: micrel.c: add rgmii interface delay possibility to ksz9131

On 25.03.2020 16:03, Philippe Schenker wrote:
> The KSZ9131 provides DLL controlled delays on RXC and TXC lines. This
> patch makes use of those delays. The information which delays should
> be enabled or disabled comes from the interface names, documented in
> ethernet-controller.yaml:
>
> rgmii: Disable RXC and TXC delays
> rgmii-id: Enable RXC and TXC delays
> rgmii-txid: Enable only TXC delay, disable RXC delay
> rgmii-rxid: Enable onlx RXC delay, disable TXC delay
>
> Signed-off-by: Philippe Schenker <[email protected]>
> ---
>
> drivers/net/phy/micrel.c | 45 ++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 45 insertions(+)
>
> diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
> index 63dedec0433d..d3ad09774847 100644
> --- a/drivers/net/phy/micrel.c
> +++ b/drivers/net/phy/micrel.c
> @@ -704,6 +704,48 @@ static int ksz9131_of_load_skew_values(struct phy_device *phydev,
> return phy_write_mmd(phydev, 2, reg, newval);
> }
>
> +/* MMD Address 0x2 */
> +#define KSZ9131RN_RXC_DLL_CTRL 76
> +#define KSZ9131RN_TXC_DLL_CTRL 77
> +#define KSZ9131RN_DLL_CTRL_BYPASS BIT_MASK(12)
> +#define KSZ9131RN_DLL_ENABLE_DELAY 0
> +#define KSZ9131RN_DLL_DISABLE_DELAY BIT(12)
> +
> +static int ksz9131_config_rgmii_delay(struct phy_device *phydev)
> +{
> + int ret;
> + u16 rxcdll_val, txcdll_val;
> +
> + switch (phydev->interface) {
> + case PHY_INTERFACE_MODE_RGMII:
> + rxcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
> + txcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
> + break;
> + case PHY_INTERFACE_MODE_RGMII_ID:
> + rxcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
> + txcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
> + break;
> + case PHY_INTERFACE_MODE_RGMII_RXID:
> + rxcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
> + txcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
> + break;
> + case PHY_INTERFACE_MODE_RGMII_TXID:
> + rxcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
> + txcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
> + break;
> + default:
> + return 0;
> + }
> +
> + ret = phy_modify_mmd_changed(phydev, 2, KSZ9131RN_RXC_DLL_CTRL,

Using a constant for the device address would be good.

Last but not least your patch misses the net-next annotation
(except you consider it a fix, then the net annotation and
a Fixes tag would be needed).

> + KSZ9131RN_DLL_CTRL_BYPASS, rxcdll_val);
> + if (ret < 0)
> + return ret;
> +
> + return phy_modify_mmd_changed(phydev, 2, KSZ9131RN_TXC_DLL_CTRL,
> + KSZ9131RN_DLL_CTRL_BYPASS, txcdll_val);
> +}
> +
> static int ksz9131_config_init(struct phy_device *phydev)
> {
> const struct device *dev = &phydev->mdio.dev;
> @@ -730,6 +772,9 @@ static int ksz9131_config_init(struct phy_device *phydev)
> if (!of_node)
> return 0;
>
> + if (phy_interface_is_rgmii(phydev))
> + ksz9131_config_rgmii_delay(phydev);
> +
> ret = ksz9131_of_load_skew_values(phydev, of_node,
> MII_KSZ9031RN_CLK_PAD_SKEW, 5,
> clk_skews, 2);
>

2020-03-25 15:48:15

by Philippe Schenker

[permalink] [raw]
Subject: Re: [PATCH 1/2] net: phy: micrel.c: add rgmii interface delay possibility to ksz9131

On Wed, 2020-03-25 at 16:24 +0100, Heiner Kallweit wrote:
> On 25.03.2020 16:03, Philippe Schenker wrote:
> > The KSZ9131 provides DLL controlled delays on RXC and TXC lines.
> > This
> > patch makes use of those delays. The information which delays should
> > be enabled or disabled comes from the interface names, documented in
> > ethernet-controller.yaml:
> >
> > rgmii: Disable RXC and TXC delays
> > rgmii-id: Enable RXC and TXC delays
> > rgmii-txid: Enable only TXC delay, disable RXC delay
> > rgmii-rxid: Enable onlx RXC delay, disable TXC delay
> >
> > Signed-off-by: Philippe Schenker <[email protected]>
> > ---
> >
> > drivers/net/phy/micrel.c | 45
> > ++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 45 insertions(+)
> >
> > diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
> > index 63dedec0433d..d3ad09774847 100644
> > --- a/drivers/net/phy/micrel.c
> > +++ b/drivers/net/phy/micrel.c
> > @@ -704,6 +704,48 @@ static int ksz9131_of_load_skew_values(struct
> > phy_device *phydev,
> > return phy_write_mmd(phydev, 2, reg, newval);
> > }
> >
> > +/* MMD Address 0x2 */
> > +#define KSZ9131RN_RXC_DLL_CTRL 76
> > +#define KSZ9131RN_TXC_DLL_CTRL 77
> > +#define KSZ9131RN_DLL_CTRL_BYPASS BIT_MASK(12)
> > +#define KSZ9131RN_DLL_ENABLE_DELAY 0
> > +#define KSZ9131RN_DLL_DISABLE_DELAY BIT(12)
> > +
> > +static int ksz9131_config_rgmii_delay(struct phy_device *phydev)
> > +{
> > + int ret;
> > + u16 rxcdll_val, txcdll_val;
> > +
>
> Reverse xmas tree order please.
>
> > + switch (phydev->interface) {
> > + case PHY_INTERFACE_MODE_RGMII:
> > + rxcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
> > + txcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
> > + break;
> > + case PHY_INTERFACE_MODE_RGMII_ID:
> > + rxcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
> > + txcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
> > + break;
> > + case PHY_INTERFACE_MODE_RGMII_RXID:
> > + rxcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
> > + txcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
> > + break;
> > + case PHY_INTERFACE_MODE_RGMII_TXID:
> > + rxcdll_val = KSZ9131RN_DLL_DISABLE_DELAY;
> > + txcdll_val = KSZ9131RN_DLL_ENABLE_DELAY;
> > + break;
> > + default:
> > + return 0;
> > + }
> > +
> > + ret = phy_modify_mmd_changed(phydev, 2, KSZ9131RN_RXC_DLL_CTRL,
> > + KSZ9131RN_DLL_CTRL_BYPASS,
> > rxcdll_val);
> > + if (ret < 0)
> > + return ret;
> > +
> > + return phy_modify_mmd_changed(phydev, 2, KSZ9131RN_TXC_DLL_CTRL,
> > + KSZ9131RN_DLL_CTRL_BYPASS,
> > txcdll_val);
>
> phy_modify_mmd_changed() returns 1 if the register value was changed,
> and that's not what you want here. Simply use phy_modify_mmd() in both
> occurrences. And your function has a return value, but it's not used
> by
> the caller.

Thanks for your feedback, I'll send a v2 with those fixes.
>
> > +}
> > +
> > static int ksz9131_config_init(struct phy_device *phydev)
> > {
> > const struct device *dev = &phydev->mdio.dev;
> > @@ -730,6 +772,9 @@ static int ksz9131_config_init(struct phy_device
> > *phydev)
> > if (!of_node)
> > return 0;
> >
> > + if (phy_interface_is_rgmii(phydev))
> > + ksz9131_config_rgmii_delay(phydev);
> > +
> > ret = ksz9131_of_load_skew_values(phydev, of_node,
> > MII_KSZ9031RN_CLK_PAD_SKEW, 5,
> > clk_skews, 2);
> >