On 19/02/2019 07:18, Vinod Koul wrote:
> Per "Documentation/devicetree/bindings/net/ethernet.txt" RGMII mode
> should not have delay in PHY whereas RGMII_ID and RGMII_RXID/RGMII_TXID
> can have delay in phy.
PHY or phy? :-)
> So disable the delay only for RGMII mode and enable for other modes.
> Also treat the default case as disabled delays.
>
> Fixes: cd28d1d6e52e: ("net: phy: at803x: Disable phy delay for RGMII mode")
> Reported-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
> Reviewed-by: Niklas Cassel <niklas.cassel@xxxxxxxxxx>
> Tested-by: Peter Ujfalusi <peter.ujflausi@xxxxxx>
> Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
> ---
> drivers/net/phy/at803x.c | 47 ++++++++++++++++++++++++++++++----------
> 1 file changed, 36 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
> index c6e7d800fd7a..dc1b13f7fc12 100644
> --- a/drivers/net/phy/at803x.c
> +++ b/drivers/net/phy/at803x.c
> @@ -110,6 +110,18 @@ static int at803x_debug_reg_mask(struct phy_device *phydev, u16 reg,
> return phy_write(phydev, AT803X_DEBUG_DATA, val);
> }
>
> +static int at803x_enable_rx_delay(struct phy_device *phydev)
> +{
> + return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0, 0,
> + AT803X_DEBUG_RX_CLK_DLY_EN);
> +}
> +
> +static int at803x_enable_tx_delay(struct phy_device *phydev)
> +{
> + return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_5, 0,
> + AT803X_DEBUG_TX_CLK_DLY_EN);
> +}
> +
> static int at803x_disable_rx_delay(struct phy_device *phydev)
> {
> return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0,
> @@ -255,23 +267,36 @@ static int at803x_config_init(struct phy_device *phydev)
> if (ret < 0)
> return ret;
>
> - if (phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID ||
> - phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
> - phydev->interface == PHY_INTERFACE_MODE_RGMII) {
> - ret = at803x_disable_rx_delay(phydev);
> + /* The hardware register default is RX and TX delay enabled, so lets
> + * first disable the RX and TX delays in phy and enable them based
> + * on the mode selected
> + */
"let's" (let us)
For the record, AFAIR, the default is not *quite* RX and TX enabled:
https://www.spinics.net/lists/netdev/msg444527.html
RX: enabled at HW reset
TX: disabled at HW reset, but retains value after SW reset
> + ret = at803x_disable_rx_delay(phydev);
> + if (ret < 0)
> + return ret;
> + ret = at803x_disable_tx_delay(phydev);
> + if (ret < 0)
> + return ret;
> +
> + if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
> + phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID) {
> + /* If RGMII_ID or RGMII_RXID are specified enable RX delay,
> + * otherwise keep it disabled
> + */
> + ret = at803x_enable_rx_delay(phydev);
> if (ret < 0)
> return ret;
> }
>
> - if (phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID ||
> - phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
> - phydev->interface == PHY_INTERFACE_MODE_RGMII) {
> - ret = at803x_disable_tx_delay(phydev);
> - if (ret < 0)
> - return ret;
> + if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
> + phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID) {
> + /* If RGMII_ID or RGMII_TXID are specified enable TX delay,
> + * otherwise keep it disabled
> + */
> + ret = at803x_enable_tx_delay(phydev);
> }
>
> - return 0;
> + return ret;
> }
IMO, the asymmetry in error handling for RX and TX is unfortunate.
Didn't you like the way it was done in my old patch? :-)
https://www.spinics.net/lists/netdev/msg445053.html
Regards.
