The GMAC1 controller in the RZN1 IP requires the RX MII clock signal to be started before it initializes its own hardware, thus before it calls phylink_start. Implement the pcs_pre_init() callback so that the RX clock signal can be enabled early if necessary. Reported-by: Clément Léger <clement.leger@xxxxxxxxxxx> Link: https://lore.kernel.org/linux-arm-kernel/20230116103926.276869-4-clement.leger@xxxxxxxxxxx/ Signed-off-by: Romain Gantois <romain.gantois@xxxxxxxxxxx> Reviewed-by: Andrew Lunn <andrew@xxxxxxx> --- drivers/net/pcs/pcs-rzn1-miic.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/drivers/net/pcs/pcs-rzn1-miic.c b/drivers/net/pcs/pcs-rzn1-miic.c index 4bd66fdde367..d0a722d43368 100644 --- a/drivers/net/pcs/pcs-rzn1-miic.c +++ b/drivers/net/pcs/pcs-rzn1-miic.c @@ -279,10 +279,38 @@ static int miic_validate(struct phylink_pcs *pcs, unsigned long *supported, return -EINVAL; } +static int miic_pre_init(struct phylink_pcs *pcs) +{ + struct miic_port *miic_port = phylink_pcs_to_miic_port(pcs); + struct miic *miic = miic_port->miic; + u32 val, mask; + + /* Start RX clock if required */ + if (pcs->rxc_always_on) { + /* In MII through mode, the clock signals will be driven by the + * external PHY, which might not be initialized yet. Set RMII + * as default mode to ensure that a reference clock signal is + * generated. + */ + miic_port->interface = PHY_INTERFACE_MODE_RMII; + + val = FIELD_PREP(MIIC_CONVCTRL_CONV_MODE, CONV_MODE_RMII) | + FIELD_PREP(MIIC_CONVCTRL_CONV_SPEED, CONV_MODE_100MBPS); + mask = MIIC_CONVCTRL_CONV_MODE | MIIC_CONVCTRL_CONV_SPEED; + + miic_reg_rmw(miic, MIIC_CONVCTRL(miic_port->port), mask, val); + + miic_converter_enable(miic, miic_port->port, 1); + } + + return 0; +} + static const struct phylink_pcs_ops miic_phylink_ops = { .pcs_validate = miic_validate, .pcs_config = miic_config, .pcs_link_up = miic_link_up, + .pcs_pre_init = miic_pre_init, }; struct phylink_pcs *miic_create(struct device *dev, struct device_node *np) -- 2.44.0
