[PATCH v2 1/2] phy: mv88e61xx: add support for RGMII TX/RX delay

[Chris Packham]

(Note: viewing on mobile device so my comment below could be wrong)

On Mon, 4 Jan 2021, 9:35 AM Pawel Dembicki, <paweldembicki at gmail.com> wrote:

> Clock delay in RGMII is required for some boards.
>
> Clock delay is read from phy-mode dts property. Delay is configured via
> proper bits in PORT_REG_PHYS_CTRL register.
>
> Cc: Chris Packham <judge.packham at gmail.com>
> Cc: Joe Hershberger <joe.hershberger at ni.com>
> Cc: Anatolij Gustschin <agust at denx.de>
> Cc: Tim Harvey <tharvey at gateworks.com>
> Cc: Tom Rini <trini at konsulko.com>
> Signed-off-by: Pawel Dembicki <paweldembicki at gmail.com>
> ---
> Changes in v2:
> - change source info about delay: from hardcode to phy-mode propoperty in
> dts
>
>  drivers/net/phy/mv88e61xx.c | 62 ++++++++++++++++++++++++++++++++++++-
>  1 file changed, 61 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/phy/mv88e61xx.c b/drivers/net/phy/mv88e61xx.c
> index 7eff37b244..70adec6578 100644
> --- a/drivers/net/phy/mv88e61xx.c
> +++ b/drivers/net/phy/mv88e61xx.c
> @@ -97,6 +97,8 @@
>  #define PORT_REG_STATUS_CMODE_1000BASE_X       0x9
>  #define PORT_REG_STATUS_CMODE_SGMII            0xa
>
> +#define PORT_REG_PHYS_CTRL_RGMII_RX_DELAY      BIT(15)
> +#define PORT_REG_PHYS_CTRL_RGMII_TX_DELAY      BIT(14)
>  #define PORT_REG_PHYS_CTRL_PCS_AN_EN   BIT(10)
>  #define PORT_REG_PHYS_CTRL_PCS_AN_RST  BIT(9)
>  #define PORT_REG_PHYS_CTRL_FC_VALUE    BIT(7)
> @@ -729,7 +731,45 @@ unforce:
>  static int mv88e61xx_fixed_port_setup(struct phy_device *phydev, u8 port)
>  {
>         struct mv88e61xx_phy_priv *priv = phydev->priv;
> -       int val;
> +       ofnode node;
> +       const char *str;
> +       int val, phy_mode;
> +       u32 phy_handle;
> +
> +       if (!ofnode_valid(phydev->node)) {
> +               node = dev_ofnode(phydev->dev);
> +               phy_handle = ofnode_read_u32_default(node, "phy-handle",
> -ENXIO);
> +
> +               if (phy_handle == -ENXIO) {
> +                       node = ofnode_first_subnode(node);
> +
> +                       while (ofnode_valid(node)) {
> +                               phy_handle = ofnode_read_u32_default(node,
> "phy-handle", -ENXIO);
> +                               if (phy_handle != -ENXIO)
> +                                       break;
> +                               node = ofnode_next_subnode(node);
> +                       }
> +               }
> +
> +               if (phy_handle != -ENXIO)
> +                       node = ofnode_get_by_phandle(phy_handle);
> +               else
> +                       node = ofnode_null();
> +       } else {
> +               node = phy_get_ofnode(phydev);
> +       }
> +
> +       node = ofnode_find_subnode(node, "ports");
> +       node = ofnode_first_subnode(node);
> +
> +       while (ofnode_valid(node)) {
> +               u8 port_no = (u8)ofnode_read_u32_default(node, "reg", -1);
> +
> +               if (port_no == port)
> +                       break;
> +
> +               node = ofnode_next_subnode(node);
> +       }
>
>         val = mv88e61xx_port_read(phydev, port, PORT_REG_PHYS_CTRL);
>         if (val < 0)
> @@ -754,6 +794,26 @@ static int mv88e61xx_fixed_port_setup(struct
> phy_device *phydev, u8 port)
>                 val |= PORT_REG_PHYS_CTRL_LINK_VALUE |
>                        PORT_REG_PHYS_CTRL_LINK_FORCE;
>

Should the 2 bits be cleared before we set them. In case there is config
from an earlier boot stage or eeprom?


> +       if (ofnode_valid(node)) {
> +               str = ofnode_read_string(node, "phy-mode");
> +               if (str)
> +                       phy_mode = phy_get_interface_by_name(str);
>

This would probably be the sensible place to clear the bits as we know we
have a phy-mode at this point.

+               switch (phy_mode) {
> +               case PHY_INTERFACE_MODE_RGMII_ID:
> +                       val |= PORT_REG_PHYS_CTRL_RGMII_RX_DELAY;
> +                       val |= PORT_REG_PHYS_CTRL_RGMII_TX_DELAY;
> +                       break;
> +               case PHY_INTERFACE_MODE_RGMII_RXID:
> +                       val |= PORT_REG_PHYS_CTRL_RGMII_RX_DELAY;
> +                       break;
> +               case PHY_INTERFACE_MODE_RGMII_TXID:
> +                       val |= PORT_REG_PHYS_CTRL_RGMII_TX_DELAY;
> +                       break;
> +               default:
> +                       break;
> +               }
> +       }
> +
>         return mv88e61xx_port_write(phydev, port, PORT_REG_PHYS_CTRL,
>                                    val);
>  }
> --
> 2.25.1
>
>