--- /dev/null
+From d9fa3835bb8913757c74af96fa8db0d621e2e980 Mon Sep 17 00:00:00 2001
+From: Jonas Gorski <jonas.gorski@gmail.com>
+Date: Mon, 9 Jun 2025 11:18:24 +0200
+Subject: [PATCH] net: dsa: b53: bcm531x5: fix cpu rgmii mode interpretation
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+b53_adjust_531x5_rgmii() incorrectly enable delays in rgmii mode, but
+disables them in rgmii-id mode. Only rgmii-txid is correctly handled.
+
+Fix this by correctly enabling rx delay in rgmii-rxid and rgmii-id
+modes, and tx delay in rgmii-txid and rgmii-id modes.
+
+Since b53_adjust_531x5_rgmii() is only called for fixed-link ports,
+these are usually used as the CPU port, connected to a MAC. This means
+the chip is assuming the role of the PHY and enabling delays is
+expected.
+
+Since this has the potential to break existing setups, add a config
+options to treat rgmii as rgmii-id, and enable it by default.
+
+I only made the quirk fixup rgmii to rgmii-id, but not rgmii-id to
+rgmii, or no delays for rgmii-rxid. My reasoning is that
+
+a) Boards not requiring internal delays are probably rather seldom, so I
+ considered the likelyhood requiring/wrongly specifying rgmii-id when
+ they need rgmii as very unlikely.
+ And if they understand the difference enough to know to use the
+ "wrong" mode, they would have hopefully noticed the discrepancy and
+ reported the issue by now.
+b) I don't want to require new users to wrongly use rgmii to get
+ rgmii-id behavior with the quirk enabled.
+
+Fixes: 967dd82ffc52 ("net: dsa: b53: Add support for Broadcom RoboSwitch")
+Reported-by: Álvaro Fernández Rojas <noltari@gmail.com>
+Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
+---
+ drivers/net/dsa/b53/Kconfig | 10 ++++++++++
+ drivers/net/dsa/b53/b53_common.c | 33 +++++++++++++++++++++++---------
+ 2 files changed, 34 insertions(+), 9 deletions(-)
+
+--- a/drivers/net/dsa/b53/Kconfig
++++ b/drivers/net/dsa/b53/Kconfig
+@@ -47,3 +47,13 @@ config B53_SERDES
+ default ARCH_BCM_NSP
+ help
+ Select to enable support for SerDes on e.g: Northstar Plus SoCs.
++
++config B53_QUIRK_IMP_RGMII_IMPLIES_DELAYS
++ bool "Treat RGMII as RGMII-ID for CPU port"
++ depends on B53
++ default y
++ help
++ Select to enable RGMII delays also in RGMII (no ID) mode for the CPU
++ port to mirror old driver behavior.
++ Enable this if your board wrongly uses RGMII instead of RGMII-ID as
++ the phy interface, but actually requires internal delays enabled.
+--- a/drivers/net/dsa/b53/b53_common.c
++++ b/drivers/net/dsa/b53/b53_common.c
+@@ -1426,6 +1426,16 @@ static void b53_adjust_531x5_rgmii(struc
+ else
+ off = B53_RGMII_CTRL_P(port);
+
++ if (IS_ENABLED(CONFIG_B53_QUIRK_IMP_RGMII_IMPLIES_DELAYS) &&
++ interface == PHY_INTERFACE_MODE_RGMII) {
++ /* Older driver versions incorrectly applied delays in
++ * PHY_INTERFACE_MODE_RGMII mode.
++ *
++ * So fixup the interface to match the old behavior.
++ */
++ interface = PHY_INTERFACE_MODE_RGMII_ID;
++ }
++
+ /* Configure the port RGMII clock delay by DLL disabled and
+ * tx_clk aligned timing (restoring to reset defaults)
+ */
+@@ -1437,19 +1447,24 @@ static void b53_adjust_531x5_rgmii(struc
+ * account for this internal delay that is inserted, otherwise
+ * the switch won't be able to receive correctly.
+ *
++ * PHY_INTERFACE_MODE_RGMII_RXID means RX internal delay, make
++ * sure that we enable the port RX clock internal sampling delay
++ * to account for this internal delay that is inserted, otherwise
++ * the switch won't be able to send correctly.
++ *
++ * PHY_INTERFACE_MODE_RGMII_ID means both RX and TX internal delay,
++ * make sure that we enable delays for both.
++ *
+ * PHY_INTERFACE_MODE_RGMII means that we are not introducing
+ * any delay neither on transmission nor reception, so the
+- * BCM53125 must also be configured accordingly to account for
+- * the lack of delay and introduce
+- *
+- * The BCM53125 switch has its RX clock and TX clock control
+- * swapped, hence the reason why we modify the TX clock path in
+- * the "RGMII" case
++ * BCM53125 must also be configured accordingly.
+ */
+- if (interface == PHY_INTERFACE_MODE_RGMII_TXID)
++ if (interface == PHY_INTERFACE_MODE_RGMII_TXID ||
++ interface == PHY_INTERFACE_MODE_RGMII_ID)
+ rgmii_ctrl |= RGMII_CTRL_DLL_TXC;
+- if (interface == PHY_INTERFACE_MODE_RGMII)
+- rgmii_ctrl |= RGMII_CTRL_DLL_TXC | RGMII_CTRL_DLL_RXC;
++ if (interface == PHY_INTERFACE_MODE_RGMII_RXID ||
++ interface == PHY_INTERFACE_MODE_RGMII_ID)
++ rgmii_ctrl |= RGMII_CTRL_DLL_RXC;
+
+ if (dev->chip_id != BCM53115_DEVICE_ID)
+ rgmii_ctrl |= RGMII_CTRL_TIMING_SEL;
+++ /dev/null
-From eb9e6142ac5f42beee48c9ec8edf1da3a3d7ff81 Mon Sep 17 00:00:00 2001
-From: Jonas Gorski <jonas.gorski@gmail.com>
-Date: Thu, 5 Jun 2025 16:39:20 +0200
-Subject: [PATCH] net: dsa: b53: invert bcm531x5 rgmii delay heuristic
-MIME-Version: 1.0
-Content-Type: text/plain; charset=UTF-8
-Content-Transfer-Encoding: 8bit
-
-When configuring the RGMII port for BCM531x5, we are only doing so in
-MLO_AN_FIXED, i.e. fixed link mode. This implies this port is used as
-cpu port and thus connected to an ethernet mac, so the switch takes the
-role of the PHY.
-
-Therefore we need to enable delays when the interface mode is rgmii-id,
-and not rgmii. Enabling delays for rgmii is wrong in any case.
-
-Also update the comment with the incomplete sentence to match what we
-are now doing, and add a comment about rgmii-id.
-
-Luckily there are at least no in-tree users of rgmii or rgmii-id mode
-that would be affected, as the only user with a defined link mode uses
-rgmii-txid, which we already handle correctly.
-
-Fixes: 967dd82ffc52 ("net: dsa: b53: Add support for Broadcom RoboSwitch")
-Reported-by: Álvaro Fernández Rojas <noltari@gmail.com>
-Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
----
- drivers/net/dsa/b53/b53_common.c | 13 ++++++-------
- 1 file changed, 6 insertions(+), 7 deletions(-)
-
---- a/drivers/net/dsa/b53/b53_common.c
-+++ b/drivers/net/dsa/b53/b53_common.c
-@@ -1363,16 +1363,15 @@ static void b53_adjust_531x5_rgmii(struc
- *
- * PHY_INTERFACE_MODE_RGMII means that we are not introducing
- * any delay neither on transmission nor reception, so the
-- * BCM53125 must also be configured accordingly to account for
-- * the lack of delay and introduce
-- *
-- * The BCM53125 switch has its RX clock and TX clock control
-- * swapped, hence the reason why we modify the TX clock path in
-- * the "RGMII" case
-+ * BCM53125 must also be configured accordingly, and not enable
-+ * either delay.
-+ *
-+ * PHY_INTERFACE_MODE_RGMII_ID means both TX internal delay and RX
-+ * interal delay, so enable delay on both paths.
- */
- if (interface == PHY_INTERFACE_MODE_RGMII_TXID)
- rgmii_ctrl |= RGMII_CTRL_DLL_TXC;
-- if (interface == PHY_INTERFACE_MODE_RGMII)
-+ if (interface == PHY_INTERFACE_MODE_RGMII_ID)
- rgmii_ctrl |= RGMII_CTRL_DLL_TXC | RGMII_CTRL_DLL_RXC;
-
- if (dev->chip_id != BCM53115_DEVICE_ID)
projects / thirdparty / openwrt.git / commitdiff
