[openwrt/openwrt] realtek: dsa: rtl931x: Fix port L2 table flushing

[LEDE Commits]

robimarko pushed a commit to openwrt/openwrt.git, branch main:
https://git.openwrt.org/84b7057fe3a83b32b69da4beb26d3f9d81a75213

commit 84b7057fe3a83b32b69da4beb26d3f9d81a75213
Author: Sven Eckelmann <se at simonwunderlich.de>
AuthorDate: Thu Oct 16 11:06:08 2025 +0200

    realtek: dsa: rtl931x: Fix port L2 table flushing
    
    The DSA driver must flush the HW FDB when a port changes from
    learning/forwarding to disabled/blocking/listening.
    
    But the implementation for RTL931x was writing the port information
    starting at bit 11 (bit 11 of the second 32-bit L2_TBL_FLUSH_CTRL
    register). But this offset is the AGG_VID and not the port. The actual
    position is 43 (bit 11 of the first register).
    
    As result, the FDB was always only flushed for the port 0 and not for the
    selected port.
    
    Fixes: 9ed609705481 ("realtek: Add HW support for RTL931X for PIE, L2 and STP aging")
    Signed-off-by: Sven Eckelmann <se at simonwunderlich.de>
    Link: https://github.com/openwrt/openwrt/pull/20422
    Signed-off-by: Robert Marko <robimarko at gmail.com>
---
 .../realtek/files-6.12/drivers/net/dsa/rtl83xx/dsa.c      | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/target/linux/realtek/files-6.12/drivers/net/dsa/rtl83xx/dsa.c b/target/linux/realtek/files-6.12/drivers/net/dsa/rtl83xx/dsa.c
index 3e698683bd..9e274f357b 100644
--- a/target/linux/realtek/files-6.12/drivers/net/dsa/rtl83xx/dsa.c
+++ b/target/linux/realtek/files-6.12/drivers/net/dsa/rtl83xx/dsa.c
@@ -1709,15 +1709,20 @@ void rtl83xx_fast_age(struct dsa_switch *ds, int port)
 	mutex_unlock(&priv->reg_mutex);
 }
 
-static void rtl931x_fast_age(struct dsa_switch *ds, int port)
+static void rtldsa_931x_fast_age(struct dsa_switch *ds, int port)
 {
 	struct rtl838x_switch_priv *priv = ds->priv;
+	u32 val;
 
-	pr_info("%s port %d\n", __func__, port);
 	mutex_lock(&priv->reg_mutex);
-	sw_w32(port << 11, RTL931X_L2_TBL_FLUSH_CTRL + 4);
 
-	sw_w32(BIT(24) | BIT(28), RTL931X_L2_TBL_FLUSH_CTRL);
+	sw_w32(0, RTL931X_L2_TBL_FLUSH_CTRL + 4);
+
+	val = 0;
+	val |= port << 11;
+	val |= BIT(24); /* compare port id */
+	val |= BIT(28); /* status - trigger flush */
+	sw_w32(val, RTL931X_L2_TBL_FLUSH_CTRL);
 
 	do { } while (sw_r32(RTL931X_L2_TBL_FLUSH_CTRL) & BIT (28));
 
@@ -1729,7 +1734,7 @@ static void rtl930x_fast_age(struct dsa_switch *ds, int port)
 	struct rtl838x_switch_priv *priv = ds->priv;
 
 	if (priv->family_id == RTL9310_FAMILY_ID)
-		return rtl931x_fast_age(ds, port);
+		return rtldsa_931x_fast_age(ds, port);
 
 	pr_debug("FAST AGE port %d\n", port);
 	mutex_lock(&priv->reg_mutex);