Re: [PATCH] net: ftgmac100: Support phyless operation
From: Florian Fainelli <f.fainelli@gmail.com>
Date: 2021-02-18 04:03:58
Also in:
lkml
On 2/17/2021 7:40 PM, William A. Kennington III wrote:
We have BMC to BMC connections that lack a PHY in between but don't want to use the NC-SI state machinery of the kernel. Instead, allow for an option to disable the phy detection and mdio logic. Signed-off-by: William A. Kennington III <redacted>
The way drivers deal with MAC to MAC connection is to use a fixed-link
Device Tree node that just presents hard coded link parameters. This
provides an emulation for the PHY library as well as user-space and
requires little Ethernet MAC driver changes other than doing something
along these lines:
/* Fetch the PHY phandle */
priv->phy_dn = of_parse_phandle(dn, "phy-handle", 0);
/* In the case of a fixed PHY, the DT node associated
* to the PHY is the Ethernet MAC DT node.
*/
if (!priv->phy_dn && of_phy_is_fixed_link(dn)) {
ret = of_phy_register_fixed_link(dn);
if (ret)
return ret;
priv->phy_dn = of_node_get(dn);
}
Can this work for you here?
quoted hunk ↗ jump to hunk
--- .../devicetree/bindings/net/ftgmac100.txt | 2 ++ drivers/net/ethernet/faraday/ftgmac100.c | 30 +++++++++++-------- 2 files changed, 19 insertions(+), 13 deletions(-)diff --git a/Documentation/devicetree/bindings/net/ftgmac100.txt b/Documentation/devicetree/bindings/net/ftgmac100.txt index 29234021f601..22c729c5fd3e 100644 --- a/Documentation/devicetree/bindings/net/ftgmac100.txt +++ b/Documentation/devicetree/bindings/net/ftgmac100.txt@@ -19,6 +19,8 @@ Optional properties: - phy-mode: See ethernet.txt file in the same directory. If the property is absent, "rgmii" is assumed. Supported values are "rgmii*" and "rmii" for aspeed parts. Other (unknown) parts will accept any value. +- no-phy: Disable any MDIO or PHY connection logic and assume the interface + is always up. - use-ncsi: Use the NC-SI stack instead of an MDIO PHY. Currently assumes rmii (100bT) but kept as a separate property in case NC-SI grows support for a gigabit link.diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c index 88bfe2107938..f2cf190654c8 100644 --- a/drivers/net/ethernet/faraday/ftgmac100.c +++ b/drivers/net/ethernet/faraday/ftgmac100.c@@ -1467,18 +1467,18 @@ static int ftgmac100_open(struct net_device *netdev) return err; } - /* When using NC-SI we force the speed to 100Mbit/s full duplex, + /* When PHYless we force the speed to 100Mbit/s full duplex, * * Otherwise we leave it set to 0 (no link), the link * message from the PHY layer will handle setting it up to * something else if needed. */ - if (priv->use_ncsi) { - priv->cur_duplex = DUPLEX_FULL; - priv->cur_speed = SPEED_100; - } else { + if (netdev->phydev) { priv->cur_duplex = 0; priv->cur_speed = 0; + } else { + priv->cur_duplex = DUPLEX_FULL; + priv->cur_speed = SPEED_100; } /* Reset the hardware */@@ -1506,14 +1506,16 @@ static int ftgmac100_open(struct net_device *netdev) if (netdev->phydev) { /* If we have a PHY, start polling */ phy_start(netdev->phydev); - } else if (priv->use_ncsi) { - /* If using NC-SI, set our carrier on and start the stack */ + } else { + /* If PHYless, set our carrier on and start the stack */ netif_carrier_on(netdev); - /* Start the NCSI device */ - err = ncsi_start_dev(priv->ndev); - if (err) - goto err_ncsi; + if (priv->use_ncsi) { + /* Start the NCSI device */ + err = ncsi_start_dev(priv->ndev); + if (err) + goto err_ncsi; + } } return 0;@@ -1725,8 +1727,8 @@ static int ftgmac100_setup_clk(struct ftgmac100 *priv) * 1000Mbit link speeds. As NCSI is limited to 100Mbit, 25MHz * is sufficient */ - rc = clk_set_rate(priv->clk, priv->use_ncsi ? FTGMAC_25MHZ : - FTGMAC_100MHZ); + rc = clk_set_rate(priv->clk, priv->netdev->phydev ? FTGMAC_100MHZ : + FTGMAC_25MHZ); if (rc) goto cleanup_clk;@@ -1837,6 +1839,8 @@ static int ftgmac100_probe(struct platform_device *pdev) priv->ndev = ncsi_register_dev(netdev, ftgmac100_ncsi_handler); if (!priv->ndev) goto err_phy_connect; + } else if (np && of_get_property(np, "no-phy", NULL)) { + dev_info(&pdev->dev, "Using PHYless interface\n"); } else if (np && of_get_property(np, "phy-handle", NULL)) { struct phy_device *phy;
-- Florian