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net: bcmgenet: Patch PHY interface for dedicated PHY driver

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When we are using a dedicated PHY driver (not the Generic PHY driver)
chances are that it is going to configure RGMII delays and do that in a
way that is incompatible with our incorrect interpretation of the
phy_interface value.

Add a quirk in order to reverse the PHY_INTERFACE_MODE_RGMII to the
value of PHY_INTERFACE_MODE_RGMII_ID such that the MAC continues to be
configured the way it used to be, but the PHY driver can account for
adding delays. Conversely when PHY_INTERFACE_MODE_RGMII_TXID is
specified, return PHY_INTERFACE_MODE_RGMII_RXID to the PHY since we will
have enabled a TXC MAC delay (id_mode_dis=0, meaning there is a delay
inserted).

This is not considered a bug fix at this point since it only affects
Broadcom STB platforms shipping with a Device Tree blob that is not
updatable in the field (quite a few devices out there) and which was
generated using the scripted Device Tree environment shipped with those
platforms' SDK.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Florian Fainelli 2021-09-17 14:55:38 -07:00 committed by David S. Miller
parent 0efcc3f201
commit b972b54a68
1 changed files with 36 additions and 2 deletions
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38
drivers/net/ethernet/broadcom/genet/bcmmii.c
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@ -286,6 +286,7 @@ int bcmgenet_mii_probe(struct net_device *dev)
struct bcmgenet_priv *priv = netdev_priv(dev);
struct device *kdev = &priv->pdev->dev;
struct device_node *dn = kdev->of_node;
phy_interface_t phy_iface = priv->phy_interface;
struct phy_device *phydev;
u32 phy_flags = 0;
int ret;
@ -300,9 +301,42 @@ int bcmgenet_mii_probe(struct net_device *dev)
priv->old_duplex = -1;
priv->old_pause = -1;
/* This is an ugly quirk but we have not been correctly interpreting
* the phy_interface values and we have done that across different
* drivers, so at least we are consistent in our mistakes.
*
* When the Generic PHY driver is in use either the PHY has been
* strapped or programmed correctly by the boot loader so we should
* stick to our incorrect interpretation since we have validated it.
*
* Now when a dedicated PHY driver is in use, we need to reverse the
* meaning of the phy_interface_mode values to something that the PHY
* driver will interpret and act on such that we have two mistakes
* canceling themselves so to speak. We only do this for the two
* modes that GENET driver officially supports on Broadcom STB chips:
* PHY_INTERFACE_MODE_RGMII and PHY_INTERFACE_MODE_RGMII_TXID. Other
* modes are not *officially* supported with the boot loader and the
* scripted environment generating Device Tree blobs for those
* platforms.
*
* Note that internal PHY, MoCA and fixed-link configurations are not
* affected because they use different phy_interface_t values or the
* Generic PHY driver.
*/
switch (priv->phy_interface) {
case PHY_INTERFACE_MODE_RGMII:
phy_iface = PHY_INTERFACE_MODE_RGMII_ID;
break;
case PHY_INTERFACE_MODE_RGMII_TXID:
phy_iface = PHY_INTERFACE_MODE_RGMII_RXID;
break;
default:
break;
}
if (dn) {
phydev = of_phy_connect(dev, priv->phy_dn, bcmgenet_mii_setup,
phy_flags, priv->phy_interface);
phy_flags, phy_iface);
if (!phydev) {
pr_err("could not attach to PHY\n");
return -ENODEV;
@ -332,7 +366,7 @@ int bcmgenet_mii_probe(struct net_device *dev)
phydev->dev_flags = phy_flags;
ret = phy_connect_direct(dev, phydev, bcmgenet_mii_setup,
priv->phy_interface);
phy_iface);
if (ret) {
pr_err("could not attach to PHY\n");
return -ENODEV;