Merge branch 'net-dsa-b53-minor-fdb-related-fixes'

Jonas Gorski says:

====================
net: dsa: b53: minor fdb related fixes

While investigating and fixing/implenting proper ARL support for
bcm63xx, I encountered multiple minor issues in the current ARL
implementation:

* The ARL multicast support was not properly enabled for older chips,
  and instead a potentially reserved bit was toggled.
* While traversing the ARL table, "Search done" triggered one final
  entry which will be invalid for 4 ARL bin chips, and failed to stop
  the search on chips with only one result register.
* For chips where we have only one result register, we only traversed at
  most half the maximum entries.

I also had a fix for IVL_SVL_SELECT which is only valid for some chips,
but since this would only have an effect for !vlan_enabled, and we
always have that enabled, it isn't really worth fixing (and rather drop
the !vlan_enabled paths).
====================

Link: https://patch.msgid.link/20251102100758.28352-1-jonas.gorski@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: kuba-moo

drivers/net/dsa/b53/b53_common.c

@@ -371,11 +371,11 @@ static void b53_set_forwarding(struct b53_device *dev, int enable)
 		 * frames should be flooded or not.
 		 */
 		b53_read8(dev, B53_CTRL_PAGE, B53_IP_MULTICAST_CTRL, &mgmt);
-		mgmt |= B53_UC_FWD_EN | B53_MC_FWD_EN | B53_IPMC_FWD_EN;
+		mgmt |= B53_UC_FWD_EN | B53_MC_FWD_EN | B53_IP_MC;
 		b53_write8(dev, B53_CTRL_PAGE, B53_IP_MULTICAST_CTRL, mgmt);
 	} else {
 		b53_read8(dev, B53_CTRL_PAGE, B53_IP_MULTICAST_CTRL, &mgmt);
-		mgmt |= B53_IP_MCAST_25;
+		mgmt |= B53_IP_MC;
 		b53_write8(dev, B53_CTRL_PAGE, B53_IP_MULTICAST_CTRL, mgmt);
 	}
 }
@@ -2037,7 +2037,7 @@ static int b53_arl_search_wait(struct b53_device *dev)
 	do {
 		b53_read8(dev, B53_ARLIO_PAGE, offset, &reg);
 		if (!(reg & ARL_SRCH_STDN))
-			return 0;
+			return -ENOENT;
 
 		if (reg & ARL_SRCH_VLID)
 			return 0;
@@ -2087,13 +2087,16 @@ static int b53_fdb_copy(int port, const struct b53_arl_entry *ent,
 int b53_fdb_dump(struct dsa_switch *ds, int port,
 		 dsa_fdb_dump_cb_t *cb, void *data)
 {
+	unsigned int count = 0, results_per_hit = 1;
 	struct b53_device *priv = ds->priv;
 	struct b53_arl_entry results[2];
-	unsigned int count = 0;
 	u8 offset;
 	int ret;
 	u8 reg;
 
+	if (priv->num_arl_bins > 2)
+		results_per_hit = 2;
+
 	mutex_lock(&priv->arl_mutex);
 
 	if (is5325(priv) || is5365(priv))
@@ -2115,7 +2118,7 @@ int b53_fdb_dump(struct dsa_switch *ds, int port,
 		if (ret)
 			break;
 
-		if (priv->num_arl_bins > 2) {
+		if (results_per_hit == 2) {
 			b53_arl_search_rd(priv, 1, &results[1]);
 			ret = b53_fdb_copy(port, &results[1], cb, data);
 			if (ret)
@@ -2125,7 +2128,7 @@ int b53_fdb_dump(struct dsa_switch *ds, int port,
 				break;
 		}
 
-	} while (count++ < b53_max_arl_entries(priv) / 2);
+	} while (count++ < b53_max_arl_entries(priv) / results_per_hit);
 
 	mutex_unlock(&priv->arl_mutex);
 

drivers/net/dsa/b53/b53_regs.h

@@ -111,8 +111,7 @@
 
 /* IP Multicast control (8 bit) */
 #define B53_IP_MULTICAST_CTRL		0x21
-#define  B53_IP_MCAST_25		BIT(0)
-#define  B53_IPMC_FWD_EN		BIT(1)
+#define  B53_IP_MC			BIT(0)
 #define  B53_UC_FWD_EN			BIT(6)
 #define  B53_MC_FWD_EN			BIT(7)