Re: [PATCH v1 2/2] net: phy: motorcomm: Add pad drive strength cfg support

From: Guo Samin
Date: Wed Apr 26 2023 - 20:55:28 EST


Re: [PATCH v1 2/2] net: phy: motorcomm: Add pad drive strength cfg support
From: Frank Sae <Frank.Sae@xxxxxxxxxxxxxx>
to: Samin Guo <samin.guo@xxxxxxxxxxxxxxxx>, <linux-kernel@xxxxxxxxxxxxxxx>, <devicetree@xxxxxxxxxxxxxxx>, <netdev@xxxxxxxxxxxxxxx>, Peter Geis <pgwipeout@xxxxxxxxx>
data: 2023/4/26

>
>
> On 2023/4/26 14:35, Samin Guo wrote:
>> The motorcomm phy (YT8531) supports the ability to adjust the drive
>> strength of the rx_clk/rx_data, and the default strength may not be
>> suitable for all boards. So add configurable options to better match
>> the boards.(e.g. StarFive VisionFive 2)
>>
>> Signed-off-by: Samin Guo <samin.guo@xxxxxxxxxxxxxxxx>
>> ---
>> drivers/net/phy/motorcomm.c | 32 ++++++++++++++++++++++++++++++++
>> 1 file changed, 32 insertions(+)
>>
>> diff --git a/drivers/net/phy/motorcomm.c b/drivers/net/phy/motorcomm.c
>> index 2fa5a90e073b..08f28ed83e60 100644
>> --- a/drivers/net/phy/motorcomm.c
>> +++ b/drivers/net/phy/motorcomm.c
>> @@ -236,6 +236,11 @@
>> */
>> #define YTPHY_WCR_TYPE_PULSE BIT(0)
>>
>> +#define YTPHY_PAD_DRIVE_STRENGTH_REG 0xA010
>> +#define YTPHY_RGMII_RXC_DS GENMASK(15, 13)
>> +#define YTPHY_RGMII_RXD_DS GENMASK(5, 4) /* Bit 1 and 0 of rgmii_rxd_ds */
>> +#define YTPHY_RGMII_RXD_DS2 BIT(12) /* Bit 2 of rgmii_rxd_ds */
>> +
>
> Please change YTPHY_RGMII_XXX to YT8531_RGMII_XXX. YT8521's reg (0xA010) is not same as this.
> Keep bit order.

will fix.

>
>> #define YTPHY_SYNCE_CFG_REG 0xA012
>> #define YT8521_SCR_SYNCE_ENABLE BIT(5)
>> /* 1b0 output 25m clock
>> @@ -1495,6 +1500,7 @@ static int yt8531_config_init(struct phy_device *phydev)
>> {
>> struct device_node *node = phydev->mdio.dev.of_node;
>> int ret;
>> + u32 val;
>>
>> ret = ytphy_rgmii_clk_delay_config_with_lock(phydev);
>> if (ret < 0)
>> @@ -1518,6 +1524,32 @@ static int yt8531_config_init(struct phy_device *phydev)
>> return ret;
>> }
>>
>> + if (!of_property_read_u32(node, "rx-clk-driver-strength", &val)) {
>
> Please check the val of "val", add the handle of default value.
>
Will fix it in the next version, thanks.
>> + ret = ytphy_modify_ext_with_lock(phydev,
>> + YTPHY_PAD_DRIVE_STRENGTH_REG,
>> + YTPHY_RGMII_RXC_DS,
>> + FIELD_PREP(YTPHY_RGMII_RXC_DS, val));
>> + if (ret < 0)
>> + return ret;
>> + }
>> +
>> + if (!of_property_read_u32(node, "rx-data-driver-strength", &val)) {
>> + if (val > FIELD_MAX(YTPHY_RGMII_RXD_DS)) {
>> + val &= FIELD_MAX(YTPHY_RGMII_RXD_DS);
>> + val = FIELD_PREP(YTPHY_RGMII_RXD_DS, val);
>> + val |= YTPHY_RGMII_RXD_DS2;
>> + } else {
>> + val = FIELD_PREP(YTPHY_RGMII_RXD_DS, val);
>> + }
>> +
>> + ret = ytphy_modify_ext_with_lock(phydev,
>> + YTPHY_PAD_DRIVE_STRENGTH_REG,
>> + YTPHY_RGMII_RXD_DS | YTPHY_RGMII_RXD_DS2,
>> + val);
>> + if (ret < 0)
>> + return ret;
>> + }
>> +
>> return 0;
>> }
>>