From 9b357ea52523f935acec153cea20f7a4fe704b48 Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Tue, 24 Jun 2025 12:53:32 +0200 Subject: dt-bindings: net: ti: k3-am654-cpsw-nuss: update phy-mode in example k3-am65-cpsw-nuss controllers have a fixed internal TX delay, so RXID mode is not actually possible and will result in a warning from the driver going forward. Signed-off-by: Matthias Schiffer Reviewed-by: Maxime Chevallier Reviewed-by: Andrew Lunn Acked-by: Rob Herring (Arm) Reviewed-by: Siddharth Vadapalli Link: https://patch.msgid.link/f9b5e84fcaf565506ed86cf1838444c2bc47334f.1750756583.git.matthias.schiffer@ew.tq-group.com Signed-off-by: Paolo Abeni --- Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml b/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml index 7b3d948f187d..a959c1d7e643 100644 --- a/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml +++ b/Documentation/devicetree/bindings/net/ti,k3-am654-cpsw-nuss.yaml @@ -284,7 +284,7 @@ examples: ti,syscon-efuse = <&mcu_conf 0x200>; phys = <&phy_gmii_sel 1>; - phy-mode = "rgmii-rxid"; + phy-mode = "rgmii-id"; phy-handle = <&phy0>; }; }; -- cgit v1.2.3 From ca13b249f291f4920466638d1adbfb3f9c8db6e9 Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Tue, 24 Jun 2025 12:53:33 +0200 Subject: net: ethernet: ti: am65-cpsw: fixup PHY mode for fixed RGMII TX delay All am65-cpsw controllers have a fixed TX delay, so the PHY interface mode must be fixed up to account for this. Modes that claim to a delay on the PCB can't actually work. Warn people to update their Device Trees if one of the unsupported modes is specified. Signed-off-by: Matthias Schiffer Reviewed-by: Maxime Chevallier Reviewed-by: Andrew Lunn Reviewed-by: Siddharth Vadapalli Link: https://patch.msgid.link/9b3fb1fbf719bef30702192155c6413cd5de5dcf.1750756583.git.matthias.schiffer@ew.tq-group.com Signed-off-by: Paolo Abeni --- drivers/net/ethernet/ti/am65-cpsw-nuss.c | 27 +++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c index f20d1ff192ef..519757e618ad 100644 --- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c +++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c @@ -2602,6 +2602,7 @@ static int am65_cpsw_nuss_init_slave_ports(struct am65_cpsw_common *common) return -ENOENT; for_each_child_of_node(node, port_np) { + phy_interface_t phy_if; struct am65_cpsw_port *port; u32 port_id; @@ -2667,14 +2668,36 @@ static int am65_cpsw_nuss_init_slave_ports(struct am65_cpsw_common *common) /* get phy/link info */ port->slave.port_np = of_node_get(port_np); - ret = of_get_phy_mode(port_np, &port->slave.phy_if); + ret = of_get_phy_mode(port_np, &phy_if); if (ret) { dev_err(dev, "%pOF read phy-mode err %d\n", port_np, ret); goto of_node_put; } - ret = phy_set_mode_ext(port->slave.ifphy, PHY_MODE_ETHERNET, port->slave.phy_if); + /* CPSW controllers supported by this driver have a fixed + * internal TX delay in RGMII mode. Fix up PHY mode to account + * for this and warn about Device Trees that claim to have a TX + * delay on the PCB. + */ + switch (phy_if) { + case PHY_INTERFACE_MODE_RGMII_ID: + phy_if = PHY_INTERFACE_MODE_RGMII_RXID; + break; + case PHY_INTERFACE_MODE_RGMII_TXID: + phy_if = PHY_INTERFACE_MODE_RGMII; + break; + case PHY_INTERFACE_MODE_RGMII: + case PHY_INTERFACE_MODE_RGMII_RXID: + dev_warn(dev, + "RGMII mode without internal TX delay unsupported; please fix your Device Tree\n"); + break; + default: + break; + } + + port->slave.phy_if = phy_if; + ret = phy_set_mode_ext(port->slave.ifphy, PHY_MODE_ETHERNET, phy_if); if (ret) goto of_node_put; -- cgit v1.2.3 From e02adac7c84bf2883ce5d5a828a03871c0c1d4f9 Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Tue, 24 Jun 2025 12:53:34 +0200 Subject: checkpatch: check for comment explaining rgmii(|-rxid|-txid) PHY modes Historically, the RGMII PHY modes specified in Device Trees have been used inconsistently, often referring to the usage of delays on the PHY side rather than describing the board; many drivers still implement this incorrectly. Require a comment in Devices Trees using these modes (usually mentioning that the delay is realized on the PCB), so we can avoid adding more incorrect uses (or will at least notice which drivers still need to be fixed). Suggested-by: Andrew Lunn Signed-off-by: Matthias Schiffer Reviewed-by: Andrew Lunn Link: https://patch.msgid.link/bc112b8aa510cf9df9ab33178d122f234d0aebf7.1750756583.git.matthias.schiffer@ew.tq-group.com Signed-off-by: Paolo Abeni --- Documentation/dev-tools/checkpatch.rst | 9 +++++++++ scripts/checkpatch.pl | 12 ++++++++++++ 2 files changed, 21 insertions(+) diff --git a/Documentation/dev-tools/checkpatch.rst b/Documentation/dev-tools/checkpatch.rst index 76bd0ddb0041..d5c47e560324 100644 --- a/Documentation/dev-tools/checkpatch.rst +++ b/Documentation/dev-tools/checkpatch.rst @@ -495,6 +495,15 @@ Comments See: https://lore.kernel.org/lkml/20131006222342.GT19510@leaf/ + **UNCOMMENTED_RGMII_MODE** + Historically, the RGMII PHY modes specified in Device Trees have been + used inconsistently, often referring to the usage of delays on the PHY + side rather than describing the board. + + PHY modes "rgmii", "rgmii-rxid" and "rgmii-txid" modes require the clock + signal to be delayed on the PCB; this unusual configuration should be + described in a comment. If they are not (meaning that the delay is realized + internally in the MAC or PHY), "rgmii-id" is the correct PHY mode. Commit message -------------- diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 664f7b7a622c..f597734d83cc 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -3741,6 +3741,18 @@ sub process { } } +# Check for RGMII phy-mode with delay on PCB + if ($realfile =~ /\.(dts|dtsi|dtso)$/ && + $line =~ /^\+\s*(phy-mode|phy-connection-type)\s*=\s*"/ && + !ctx_has_comment($first_line, $linenr)) { + my $prop = $1; + my $mode = get_quoted_string($line, $rawline); + if ($mode =~ /^"rgmii(?:|-rxid|-txid)"$/) { + WARN("UNCOMMENTED_RGMII_MODE", + "$prop $mode without comment -- delays on the PCB should be described, otherwise use \"rgmii-id\"\n" . $herecurr); + } + } + # check for using SPDX license tag at beginning of files if ($realline == $checklicenseline) { if ($rawline =~ /^[ \+]\s*\#\!\s*\//) { -- cgit v1.2.3