Re: [PATCH net-next 3/5] net: lan966x: add port module support

Russell King (Oracle)
2021-11-17T09:54:38Z

Hi,

On Wed, Nov 17, 2021 at 10:18:56AM +0100, Horatiu Vultur wrote:
> +static void lan966x_phylink_mac_link_state(struct phylink_config *config,
> + struct phylink_link_state *state)
> +{
> +}
> +
> +static void lan966x_phylink_mac_aneg_restart(struct phylink_config *config)
> +{
> +}

Since you always attach a PCS, it is not necessary to provide stubs
for these functions.

> +static int lan966x_pcs_config(struct phylink_pcs *pcs,
> + unsigned int mode,
> + phy_interface_t interface,
> + const unsigned long *advertising,
> + bool permit_pause_to_mac)
> +{
> + struct lan966x_port *port = lan966x_pcs_to_port(pcs);
> + struct lan966x_port_config config;
> + int ret;
> +
> + memset(&config, 0, sizeof(config));
> +
> + config = port->config;
> + config.portmode = interface;
> + config.inband = phylink_autoneg_inband(mode);
> + config.autoneg = phylink_test(advertising, Autoneg);
> + if (phylink_test(advertising, Pause))
> + config.pause_adv |= ADVERTISE_1000XPAUSE;
> + if (phylink_test(advertising, Asym_Pause))
> + config.pause_adv |= ADVERTISE_1000XPSE_ASYM;

There are patches around that add
phylink_mii_c22_pcs_encode_advertisement() which will create the C22
advertisement for you. It would be good to get that patch merged so
people can use it. That should also eliminate lan966x_get_aneg_word(),
although I notice you need to set ADVERTISE_LPACK as well (can you
check that please? Hardware should be managing that bit as it should
only be set once the hardware has received the link partner's
advertisement.)

> +static void decode_cl37_word(u16 lp_abil, uint16_t ld_abil,
> + struct lan966x_port_status *status)
> +{
> + status->link = !(lp_abil & ADVERTISE_RFAULT) && status->link;
> + status->an_complete = true;
> + status->duplex = (ADVERTISE_1000XFULL & lp_abil) ?
> + DUPLEX_FULL : DUPLEX_UNKNOWN;
> +
> + if ((ld_abil & ADVERTISE_1000XPAUSE) &&
> + (lp_abil & ADVERTISE_1000XPAUSE)) {
> + status->pause = MLO_PAUSE_RX | MLO_PAUSE_TX;
> + } else if ((ld_abil & ADVERTISE_1000XPSE_ASYM) &&
> + (lp_abil & ADVERTISE_1000XPSE_ASYM)) {
> + status->pause |= (lp_abil & ADVERTISE_1000XPAUSE) ?
> + MLO_PAUSE_TX : 0;
> + status->pause |= (ld_abil & ADVERTISE_1000XPAUSE) ?
> + MLO_PAUSE_RX : 0;
> + } else {
> + status->pause = MLO_PAUSE_NONE;
> + }
> +}

We already have phylink_decode_c37_word() which will decode this for
you, although it would need to be exported. Please re-use this code.

> +
> +static void decode_sgmii_word(u16 lp_abil, struct lan966x_port_status *status)
> +{
> + status->an_complete = true;
> + if (!(lp_abil & LPA_SGMII_LINK)) {
> + status->link = false;
> + return;
> + }
> +
> + switch (lp_abil & LPA_SGMII_SPD_MASK) {
> + case LPA_SGMII_10:
> + status->speed = SPEED_10;
> + break;
> + case LPA_SGMII_100:
> + status->speed = SPEED_100;
> + break;
> + case LPA_SGMII_1000:
> + status->speed = SPEED_1000;
> + break;
> + default:
> + status->link = false;
> + return;
> + }
> + if (lp_abil & LPA_SGMII_FULL_DUPLEX)
> + status->duplex = DUPLEX_FULL;
> + else
> + status->duplex = DUPLEX_HALF;
> +}

The above mentioned function will also handle SGMII as well.

> +int lan966x_port_pcs_set(struct lan966x_port *port,
> + struct lan966x_port_config *config)
> +{
> + struct lan966x *lan966x = port->lan966x;
> + bool sgmii = false, inband_aneg = false;
> + int err;
> +
> + lan966x_port_link_down(port);
> +
> + if (config->inband) {
> + if (config->portmode == PHY_INTERFACE_MODE_SGMII ||
> + config->portmode == PHY_INTERFACE_MODE_QSGMII)
> + inband_aneg = true; /* Cisco-SGMII in-band-aneg */
> + else if (config->portmode == PHY_INTERFACE_MODE_1000BASEX &&
> + config->autoneg)
> + inband_aneg = true; /* Clause-37 in-band-aneg */
> +
> + if (config->speed > 0) {
> + err = phy_set_speed(port->serdes, config->speed);
> + if (err)
> + return err;
> + }
> +
> + } else {
> + sgmii = true; /* Phy is connnected to the MAC */

This looks weird. SGMII can be in-band as well (and technically is
in-band in its as-specified form.)

> + }
> +
> + /* Choose SGMII or 1000BaseX/2500BaseX PCS mode */
> + lan_rmw(DEV_PCS1G_MODE_CFG_SGMII_MODE_ENA_SET(sgmii),
> + DEV_PCS1G_MODE_CFG_SGMII_MODE_ENA,
> + lan966x, DEV_PCS1G_MODE_CFG(port->chip_port));

With the code as you have it, what this means is if we specify
SGMII + in-band, we end up configuring the port to be in 1000BaseX
mode, so it's incapable of 10 and 100M speeds. This seems incorrect.

Thanks.

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