6.6-stable review patch. If anyone has any objections, please let me know.
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From: Vladimir Oltean vladimir.oltean@nxp.com
[ Upstream commit 734f06db599f66d6a159c78abfdbadfea3b7d43b ]
Since commit 5d93cfcf7360 ("net: dpaa: Convert to phylink"), we support the "10gbase-r" phy-mode through a driver-based conversion of "xgmii", but we still don't actually support it when the device tree specifies "10gbase-r" proper.
This is because boards such as LS1046A-RDB do not define pcs-handle-names (for whatever reason) in the ethernet@f0000 device tree node, and the code enters through this code path:
err = of_property_match_string(mac_node, "pcs-handle-names", "xfi"); // code takes neither branch and falls through if (err >= 0) { (...) } else if (err != -EINVAL && err != -ENODATA) { goto _return_fm_mac_free; }
(...)
/* For compatibility, if pcs-handle-names is missing, we assume this * phy is the first one in pcsphy-handle */ err = of_property_match_string(mac_node, "pcs-handle-names", "sgmii"); if (err == -EINVAL || err == -ENODATA) pcs = memac_pcs_create(mac_node, 0); // code takes this branch else if (err < 0) goto _return_fm_mac_free; else pcs = memac_pcs_create(mac_node, err);
// A default PCS is created and saved in "pcs"
// This determination fails and mistakenly saves the default PCS // memac->sgmii_pcs instead of memac->xfi_pcs, because at this // stage, mac_dev->phy_if == PHY_INTERFACE_MODE_10GBASER. if (err && mac_dev->phy_if == PHY_INTERFACE_MODE_XGMII) memac->xfi_pcs = pcs; else memac->sgmii_pcs = pcs;
In other words, in the absence of pcs-handle-names, the default xfi_pcs assignment logic only works when in the device tree we have PHY_INTERFACE_MODE_XGMII.
By reversing the order between the fallback xfi_pcs assignment and the "xgmii" overwrite with "10gbase-r", we are able to support both values in the device tree, with identical behavior.
Currently, it is impossible to make the s/xgmii/10gbase-r/ device tree conversion, because it would break forward compatibility (new device tree with old kernel). The only way to modify existing device trees to phy-interface-mode = "10gbase-r" is to fix stable kernels to accept this value and handle it properly.
One reason why the conversion is desirable is because with pre-phylink kernels, the Aquantia PHY driver used to warn about the improper use of PHY_INTERFACE_MODE_XGMII [1]. It is best to have a single (latest) device tree that works with all supported stable kernel versions.
Note that the blamed commit does not constitute a regression per se. Older stable kernels like 6.1 still do not work with "10gbase-r", but for a different reason. That is a battle for another time.
[1] https://lore.kernel.org/netdev/20240214-ls1046-dts-use-10gbase-r-v1-1-8c2d68...
Fixes: 5d93cfcf7360 ("net: dpaa: Convert to phylink") Signed-off-by: Vladimir Oltean vladimir.oltean@nxp.com Reviewed-by: Sean Anderson sean.anderson@seco.com Acked-by: Madalin Bucur madalin.bucur@oss.nxp.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- .../net/ethernet/freescale/fman/fman_memac.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/drivers/net/ethernet/freescale/fman/fman_memac.c b/drivers/net/ethernet/freescale/fman/fman_memac.c index 3b75cc543be93..76e5181789cb9 100644 --- a/drivers/net/ethernet/freescale/fman/fman_memac.c +++ b/drivers/net/ethernet/freescale/fman/fman_memac.c @@ -1074,6 +1074,14 @@ int memac_initialization(struct mac_device *mac_dev, unsigned long capabilities; unsigned long *supported;
+ /* The internal connection to the serdes is XGMII, but this isn't + * really correct for the phy mode (which is the external connection). + * However, this is how all older device trees say that they want + * 10GBASE-R (aka XFI), so just convert it for them. + */ + if (mac_dev->phy_if == PHY_INTERFACE_MODE_XGMII) + mac_dev->phy_if = PHY_INTERFACE_MODE_10GBASER; + mac_dev->phylink_ops = &memac_mac_ops; mac_dev->set_promisc = memac_set_promiscuous; mac_dev->change_addr = memac_modify_mac_address; @@ -1140,7 +1148,7 @@ int memac_initialization(struct mac_device *mac_dev, * (and therefore that xfi_pcs cannot be set). If we are defaulting to * XGMII, assume this is for XFI. Otherwise, assume it is for SGMII. */ - if (err && mac_dev->phy_if == PHY_INTERFACE_MODE_XGMII) + if (err && mac_dev->phy_if == PHY_INTERFACE_MODE_10GBASER) memac->xfi_pcs = pcs; else memac->sgmii_pcs = pcs; @@ -1154,14 +1162,6 @@ int memac_initialization(struct mac_device *mac_dev, goto _return_fm_mac_free; }
- /* The internal connection to the serdes is XGMII, but this isn't - * really correct for the phy mode (which is the external connection). - * However, this is how all older device trees say that they want - * 10GBASE-R (aka XFI), so just convert it for them. - */ - if (mac_dev->phy_if == PHY_INTERFACE_MODE_XGMII) - mac_dev->phy_if = PHY_INTERFACE_MODE_10GBASER; - /* TODO: The following interface modes are supported by (some) hardware * but not by this driver: * - 1000BASE-KX