Re: [PATCH v2 1/2] net: dsa: lantiq: allow to use all GPHYs on xRX300 and xRX330

From: Vladimir Oltean
Date: Sun Dec 06 2020 - 13:55:37 EST


On Sun, Dec 06, 2020 at 02:27:12PM +0100, Aleksander Jan Bajkowski wrote:
> This patch allows to use all PHYs on GRX300 and GRX330. The ARX300 has 3
> and the GRX330 has 4 integrated PHYs connected to different ports compared
> to VRX200.
>
> Port configurations:
>
> xRX200:
> GMAC0: RGMII/MII/REVMII/RMII port
> GMAC1: RGMII/MII/REVMII/RMII port
> GMAC2: GPHY0 (GMII)
> GMAC3: GPHY0 (MII)
> GMAC4: GPHY1 (GMII)
> GMAC5: GPHY1 (MII) or RGMII port
>
> xRX300:
> GMAC0: RGMII port
> GMAC1: GPHY2 (GMII)
> GMAC2: GPHY0 (GMII)
> GMAC3: GPHY0 (MII)
> GMAC4: GPHY1 (GMII)
> GMAC5: GPHY1 (MII) or RGMII port
>
> xRX330:
> GMAC0: RGMII/GMII/RMII port
> GMAC1: GPHY2 (GMII)
> GMAC2: GPHY0 (GMII)
> GMAC3: GPHY0 (MII) or GPHY3 (GMII)
> GMAC4: GPHY1 (GMII)
> GMAC5: GPHY1 (MII) or RGMII/RMII port

When you say GMII/MII when you are talking to the GPHY ports, what you
are really talking about is 1000Base-T vs 100Base-TX, right?

How about xRX330, does that really expose the full parallel GMAC pinout
on GMAC0?

>
> Tested on D-Link DWR966 with OpenWRT.
>
> Signed-off-by: Aleksander Jan Bajkowski <olek2@xxxxx>
> ---
> drivers/net/dsa/lantiq_gswip.c | 170 +++++++++++++++++++++++++++------
> 1 file changed, 141 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/net/dsa/lantiq_gswip.c b/drivers/net/dsa/lantiq_gswip.c
> index 09701c17f3f6..4c8f611ed397 100644
> --- a/drivers/net/dsa/lantiq_gswip.c
> +++ b/drivers/net/dsa/lantiq_gswip.c
> @@ -94,6 +94,7 @@
> /* GSWIP MII Registers */
> #define GSWIP_MII_CFG0 0x00
> #define GSWIP_MII_CFG1 0x02
> +#define GSWIP_MII_CFG3 0xc3
> #define GSWIP_MII_CFG5 0x04
> #define GSWIP_MII_CFG_EN BIT(14)
> #define GSWIP_MII_CFG_LDCLKDIS BIT(12)
> @@ -102,6 +103,7 @@
> #define GSWIP_MII_CFG_MODE_RMIIP 0x2
> #define GSWIP_MII_CFG_MODE_RMIIM 0x3
> #define GSWIP_MII_CFG_MODE_RGMII 0x4
> +#define GSWIP_MII_CFG_MODE_GMII 0x9
> #define GSWIP_MII_CFG_MODE_MASK 0xf
> #define GSWIP_MII_CFG_RATE_M2P5 0x00
> #define GSWIP_MII_CFG_RATE_M25 0x10
> @@ -222,6 +224,7 @@
> struct gswip_hw_info {
> int max_ports;
> int cpu_port;
> + struct dsa_switch_ops *ops;
> };
>
> struct xway_gphy_match_data {
> @@ -392,12 +395,19 @@ static void gswip_mii_mask(struct gswip_priv *priv, u32 clear, u32 set,
> static void gswip_mii_mask_cfg(struct gswip_priv *priv, u32 clear, u32 set,
> int port)
> {
> + struct device_node *np = priv->ds->dev->of_node;
> +
> switch (port) {
> case 0:
> gswip_mii_mask(priv, clear, set, GSWIP_MII_CFG0);
> break;
> case 1:
> - gswip_mii_mask(priv, clear, set, GSWIP_MII_CFG1);
> + if (of_device_is_compatible(np, "lantiq,xrx200-gswip"))
> + gswip_mii_mask(priv, clear, set, GSWIP_MII_CFG1);
> + break;
> + case 3:
> + if (of_device_is_compatible(np, "lantiq,xrx330-gswip"))
> + gswip_mii_mask(priv, clear, set, GSWIP_MII_CFG3);
> break;
> case 5:
> gswip_mii_mask(priv, clear, set, GSWIP_MII_CFG5);
> @@ -1409,12 +1419,40 @@ static int gswip_port_fdb_dump(struct dsa_switch *ds, int port,
> return 0;
> }
>
> -static void gswip_phylink_validate(struct dsa_switch *ds, int port,
> - unsigned long *supported,
> - struct phylink_link_state *state)
> +static void gswip_phylink_set_capab(unsigned long *supported, struct phylink_link_state *state)
> {
> __ETHTOOL_DECLARE_LINK_MODE_MASK(mask) = { 0, };
>
> + /* Allow all the expected bits */
> + phylink_set(mask, Autoneg);
> + phylink_set_port_modes(mask);
> + phylink_set(mask, Pause);
> + phylink_set(mask, Asym_Pause);
> +
> + /* With the exclusion of MII and Reverse MII, we support Gigabit,
> + * including Half duplex
> + */
> + if (state->interface != PHY_INTERFACE_MODE_MII &&
> + state->interface != PHY_INTERFACE_MODE_REVMII) {
> + phylink_set(mask, 1000baseT_Full);
> + phylink_set(mask, 1000baseT_Half);
> + }
> +
> + phylink_set(mask, 10baseT_Half);
> + phylink_set(mask, 10baseT_Full);
> + phylink_set(mask, 100baseT_Half);
> + phylink_set(mask, 100baseT_Full);
> +
> + bitmap_and(supported, supported, mask,
> + __ETHTOOL_LINK_MODE_MASK_NBITS);
> + bitmap_and(state->advertising, state->advertising, mask,
> + __ETHTOOL_LINK_MODE_MASK_NBITS);
> +}
> +
> +static void gswip_xrx200_phylink_validate(struct dsa_switch *ds, int port,
> + unsigned long *supported,
> + struct phylink_link_state *state)
> +{
> switch (port) {
> case 0:
> case 1:
> @@ -1441,37 +1479,56 @@ static void gswip_phylink_validate(struct dsa_switch *ds, int port,
> return;
> }
>
> - /* Allow all the expected bits */
> - phylink_set(mask, Autoneg);
> - phylink_set_port_modes(mask);
> - phylink_set(mask, Pause);
> - phylink_set(mask, Asym_Pause);
> + gswip_phylink_set_capab(supported, state);
>
> - /* With the exclusion of MII and Reverse MII, we support Gigabit,
> - * including Half duplex
> - */
> - if (state->interface != PHY_INTERFACE_MODE_MII &&
> - state->interface != PHY_INTERFACE_MODE_REVMII) {
> - phylink_set(mask, 1000baseT_Full);
> - phylink_set(mask, 1000baseT_Half);
> + return;
> +
> +unsupported:
> + bitmap_zero(supported, __ETHTOOL_LINK_MODE_MASK_NBITS);
> + dev_err(ds->dev, "Unsupported interface '%s' for port %d\n",
> + phy_modes(state->interface), port);
> +}
> +
> +static void gswip_xrx300_phylink_validate(struct dsa_switch *ds, int port,
> + unsigned long *supported,
> + struct phylink_link_state *state)
> +{
> + __ETHTOOL_DECLARE_LINK_MODE_MASK(mask) = { 0, };
> +
> + switch (port) {
> + case 0:
> + if (!phy_interface_mode_is_rgmii(state->interface) &&
> + state->interface != PHY_INTERFACE_MODE_GMII &&
> + state->interface != PHY_INTERFACE_MODE_RMII)
> + goto unsupported;
> + break;
> + case 1:
> + case 2:
> + case 3:
> + case 4:
> + if (state->interface != PHY_INTERFACE_MODE_INTERNAL)
> + goto unsupported;
> + break;
> + case 5:
> + if (!phy_interface_mode_is_rgmii(state->interface) &&
> + state->interface != PHY_INTERFACE_MODE_INTERNAL &&
> + state->interface != PHY_INTERFACE_MODE_RMII)
> + goto unsupported;
> + break;
> + default:
> + bitmap_zero(supported, __ETHTOOL_LINK_MODE_MASK_NBITS);
> + dev_err(ds->dev, "Unsupported port: %i\n", port);
> + return;
> }

I think there is a pre-existing issue in gswip_phylink_validate in that
when state->interface == PHY_INTERFACE_MODE_NA, this triggers the "goto
unsupported" code path, when it should instead report all supported link
modes. phylink calls phylink_validate() with PHY_INTERFACE_MODE_NA when
the MII protocol is not known off-hand but depends on what is attached /
what that is configured to advertise.

In your case I think it is a bit unlikely to have a clause 45 PHY that
changes MII protocol dynamically, or an SFP module attached directly to
your GMAC, given that on the port without an internal PHY you only have
parallel interfaces and not a SERDES (note that there still exist RGMII
PHYs - see RTL8211FS - that have an optical media side and can therefore
be connected to an SFP cage, but I don't really know how phylink deals
with those given the structure of sfp_select_interface). So it is mainly
a question of API compliance. Do we want to allow drivers to ignore
something than the API requires, because the driver writers know that
the code path will not be executed in real life.

>
> - phylink_set(mask, 10baseT_Half);
> - phylink_set(mask, 10baseT_Full);
> - phylink_set(mask, 100baseT_Half);
> - phylink_set(mask, 100baseT_Full);
> + gswip_phylink_set_capab(supported, state);
>
> - bitmap_and(supported, supported, mask,
> - __ETHTOOL_LINK_MODE_MASK_NBITS);
> - bitmap_and(state->advertising, state->advertising, mask,
> - __ETHTOOL_LINK_MODE_MASK_NBITS);
> return;
>
> unsupported:
> bitmap_zero(supported, __ETHTOOL_LINK_MODE_MASK_NBITS);
> dev_err(ds->dev, "Unsupported interface '%s' for port %d\n",
> phy_modes(state->interface), port);
> - return;
> }
>
> static void gswip_phylink_mac_config(struct dsa_switch *ds, int port,
> @@ -1500,6 +1557,9 @@ static void gswip_phylink_mac_config(struct dsa_switch *ds, int port,
> case PHY_INTERFACE_MODE_RGMII_TXID:
> miicfg |= GSWIP_MII_CFG_MODE_RGMII;
> break;
> + case PHY_INTERFACE_MODE_GMII:
> + miicfg |= GSWIP_MII_CFG_MODE_GMII;
> + break;
> default:
> dev_err(ds->dev,
> "Unsupported interface: %d\n", state->interface);
> @@ -1614,7 +1674,7 @@ static int gswip_get_sset_count(struct dsa_switch *ds, int port, int sset)
> return ARRAY_SIZE(gswip_rmon_cnt);
> }
>
> -static const struct dsa_switch_ops gswip_switch_ops = {
> +static const struct dsa_switch_ops gswip_xrx200_switch_ops = {
> .get_tag_protocol = gswip_get_tag_protocol,
> .setup = gswip_setup,
> .port_enable = gswip_port_enable,
> @@ -1630,7 +1690,32 @@ static const struct dsa_switch_ops gswip_switch_ops = {
> .port_fdb_add = gswip_port_fdb_add,
> .port_fdb_del = gswip_port_fdb_del,
> .port_fdb_dump = gswip_port_fdb_dump,
> - .phylink_validate = gswip_phylink_validate,
> + .phylink_validate = gswip_xrx200_phylink_validate,
> + .phylink_mac_config = gswip_phylink_mac_config,
> + .phylink_mac_link_down = gswip_phylink_mac_link_down,
> + .phylink_mac_link_up = gswip_phylink_mac_link_up,
> + .get_strings = gswip_get_strings,
> + .get_ethtool_stats = gswip_get_ethtool_stats,
> + .get_sset_count = gswip_get_sset_count,
> +};
> +
> +static const struct dsa_switch_ops gswip_xrx300_switch_ops = {
> + .get_tag_protocol = gswip_get_tag_protocol,
> + .setup = gswip_setup,
> + .port_enable = gswip_port_enable,
> + .port_disable = gswip_port_disable,
> + .port_bridge_join = gswip_port_bridge_join,
> + .port_bridge_leave = gswip_port_bridge_leave,
> + .port_fast_age = gswip_port_fast_age,
> + .port_vlan_filtering = gswip_port_vlan_filtering,
> + .port_vlan_prepare = gswip_port_vlan_prepare,
> + .port_vlan_add = gswip_port_vlan_add,
> + .port_vlan_del = gswip_port_vlan_del,
> + .port_stp_state_set = gswip_port_stp_state_set,
> + .port_fdb_add = gswip_port_fdb_add,
> + .port_fdb_del = gswip_port_fdb_del,
> + .port_fdb_dump = gswip_port_fdb_dump,
> + .phylink_validate = gswip_xrx300_phylink_validate,
> .phylink_mac_config = gswip_phylink_mac_config,
> .phylink_mac_link_down = gswip_phylink_mac_link_down,
> .phylink_mac_link_up = gswip_phylink_mac_link_up,
> @@ -1859,7 +1944,7 @@ static int gswip_gphy_fw_list(struct gswip_priv *priv,
> static int gswip_probe(struct platform_device *pdev)
> {
> struct gswip_priv *priv;
> - struct device_node *mdio_np, *gphy_fw_np;
> + struct device_node *np, *mdio_np, *gphy_fw_np;
> struct device *dev = &pdev->dev;
> int err;
> int i;
> @@ -1892,10 +1977,28 @@ static int gswip_probe(struct platform_device *pdev)
> priv->ds->dev = dev;
> priv->ds->num_ports = priv->hw_info->max_ports;
> priv->ds->priv = priv;
> - priv->ds->ops = &gswip_switch_ops;
> + priv->ds->ops = priv->hw_info->ops;
> priv->dev = dev;
> version = gswip_switch_r(priv, GSWIP_VERSION);
>
> + np = dev->of_node;
> + switch (version) {
> + case GSWIP_VERSION_2_0:
> + case GSWIP_VERSION_2_1:
> + if (!of_device_is_compatible(np, "lantiq,xrx200-gswip"))
> + return -EINVAL;
> + break;
> + case GSWIP_VERSION_2_2:
> + case GSWIP_VERSION_2_2_ETC:
> + if (!of_device_is_compatible(np, "lantiq,xrx300-gswip") &&
> + !of_device_is_compatible(np, "lantiq,xrx330-gswip"))
> + return -EINVAL;
> + break;
> + default:
> + dev_err(dev, "unknown GSWIP version: 0x%x", version);
> + return -ENOENT;
> + }
> +
> /* bring up the mdio bus */
> gphy_fw_np = of_get_compatible_child(dev->of_node, "lantiq,gphy-fw");
> if (gphy_fw_np) {
> @@ -1973,10 +2076,19 @@ static int gswip_remove(struct platform_device *pdev)
> static const struct gswip_hw_info gswip_xrx200 = {
> .max_ports = 7,
> .cpu_port = 6,
> + .ops = &gswip_xrx200_switch_ops,
> +};
> +
> +static const struct gswip_hw_info gswip_xrx300 = {
> + .max_ports = 7,
> + .cpu_port = 6,
> + .ops = &gswip_xrx300_switch_ops,
> };
>
> static const struct of_device_id gswip_of_match[] = {
> { .compatible = "lantiq,xrx200-gswip", .data = &gswip_xrx200 },
> + { .compatible = "lantiq,xrx300-gswip", .data = &gswip_xrx300 },
> + { .compatible = "lantiq,xrx330-gswip", .data = &gswip_xrx300 },
> {},
> };
> MODULE_DEVICE_TABLE(of, gswip_of_match);
> --
> 2.20.1
>