Merge branch 'net-dsa-b53-fix-bcm5325-support'

Álvaro Fernández Rojas says:

====================
net: dsa: b53: fix BCM5325 support

These patches get the BCM5325 switch working with b53.

The existing brcm legacy tag only works with BCM63xx switches.
We need to add a new legacy tag for BCM5325 and BCM5365 switches, which
require including the FCS and length.

I'm not really sure that everything here is correct since I don't work for
Broadcom and all this is based on the public datasheet available for the
BCM5325 and my own experiments with a Huawei HG556a (BCM6358).

Both sets of patches have been merged due to the change requested by Jonas
about BRCM_HDR register access depending on legacy tags.
====================

Link: https://patch.msgid.link/20250614080000.1884236-1-noltari@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

7 files changed, 408 insertions, 89 deletions

diff --git a/drivers/net/dsa/b53/Kconfig b/drivers/net/dsa/b53/Kconfig
index ebaa4a80d544..915008e8eff5 100644
--- a/drivers/net/dsa/b53/Kconfig
+++ b/drivers/net/dsa/b53/Kconfig
@@ -5,6 +5,7 @@ menuconfig B53
 	select NET_DSA_TAG_NONE
 	select NET_DSA_TAG_BRCM
 	select NET_DSA_TAG_BRCM_LEGACY
+	select NET_DSA_TAG_BRCM_LEGACY_FCS
 	select NET_DSA_TAG_BRCM_PREPEND
 	help
 	  This driver adds support for Broadcom managed switch chips. It supports
diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c
index dc2f4adac9bc..46978757c972 100644
--- a/drivers/net/dsa/b53/b53_common.c
+++ b/drivers/net/dsa/b53/b53_common.c
@@ -361,18 +361,23 @@ static void b53_set_forwarding(struct b53_device *dev, int enable)
 
 	b53_write8(dev, B53_CTRL_PAGE, B53_SWITCH_MODE, mgmt);
 
-	/* Include IMP port in dumb forwarding mode
-	 */
-	b53_read8(dev, B53_CTRL_PAGE, B53_SWITCH_CTRL, &mgmt);
-	mgmt |= B53_MII_DUMB_FWDG_EN;
-	b53_write8(dev, B53_CTRL_PAGE, B53_SWITCH_CTRL, mgmt);
-
-	/* Look at B53_UC_FWD_EN and B53_MC_FWD_EN to decide whether
-	 * 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;
-	b53_write8(dev, B53_CTRL_PAGE, B53_IP_MULTICAST_CTRL, mgmt);
+	if (!is5325(dev)) {
+		/* Include IMP port in dumb forwarding mode */
+		b53_read8(dev, B53_CTRL_PAGE, B53_SWITCH_CTRL, &mgmt);
+		mgmt |= B53_MII_DUMB_FWDG_EN;
+		b53_write8(dev, B53_CTRL_PAGE, B53_SWITCH_CTRL, mgmt);
+
+		/* Look at B53_UC_FWD_EN and B53_MC_FWD_EN to decide whether
+		 * 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;
+		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;
+		b53_write8(dev, B53_CTRL_PAGE, B53_IP_MULTICAST_CTRL, mgmt);
+	}
 }
 
 static void b53_enable_vlan(struct b53_device *dev, int port, bool enable,
@@ -487,6 +492,9 @@ static int b53_flush_arl(struct b53_device *dev, u8 mask)
 {
 	unsigned int i;
 
+	if (is5325(dev))
+		return 0;
+
 	b53_write8(dev, B53_CTRL_PAGE, B53_FAST_AGE_CTRL,
 		   FAST_AGE_DONE | FAST_AGE_DYNAMIC | mask);
 
@@ -511,6 +519,9 @@ out:
 
 static int b53_fast_age_port(struct b53_device *dev, int port)
 {
+	if (is5325(dev))
+		return 0;
+
 	b53_write8(dev, B53_CTRL_PAGE, B53_FAST_AGE_PORT_CTRL, port);
 
 	return b53_flush_arl(dev, FAST_AGE_PORT);
@@ -518,6 +529,9 @@ static int b53_fast_age_port(struct b53_device *dev, int port)
 
 static int b53_fast_age_vlan(struct b53_device *dev, u16 vid)
 {
+	if (is5325(dev))
+		return 0;
+
 	b53_write16(dev, B53_CTRL_PAGE, B53_FAST_AGE_VID_CTRL, vid);
 
 	return b53_flush_arl(dev, FAST_AGE_VLAN);
@@ -529,6 +543,10 @@ void b53_imp_vlan_setup(struct dsa_switch *ds, int cpu_port)
 	unsigned int i;
 	u16 pvlan;
 
+	/* BCM5325 CPU port is at 8 */
+	if ((is5325(dev) || is5365(dev)) && cpu_port == B53_CPU_PORT_25)
+		cpu_port = B53_CPU_PORT;
+
 	/* Enable the IMP port to be in the same VLAN as the other ports
 	 * on a per-port basis such that we only have Port i and IMP in
 	 * the same VLAN.
@@ -546,12 +564,24 @@ static void b53_port_set_ucast_flood(struct b53_device *dev, int port,
 {
 	u16 uc;
 
-	b53_read16(dev, B53_CTRL_PAGE, B53_UC_FLOOD_MASK, &uc);
-	if (unicast)
-		uc |= BIT(port);
-	else
-		uc &= ~BIT(port);
-	b53_write16(dev, B53_CTRL_PAGE, B53_UC_FLOOD_MASK, uc);
+	if (is5325(dev)) {
+		if (port == B53_CPU_PORT_25)
+			port = B53_CPU_PORT;
+
+		b53_read16(dev, B53_IEEE_PAGE, B53_IEEE_UCAST_DLF, &uc);
+		if (unicast)
+			uc |= BIT(port) | B53_IEEE_UCAST_DROP_EN;
+		else
+			uc &= ~BIT(port);
+		b53_write16(dev, B53_IEEE_PAGE, B53_IEEE_UCAST_DLF, uc);
+	} else {
+		b53_read16(dev, B53_CTRL_PAGE, B53_UC_FLOOD_MASK, &uc);
+		if (unicast)
+			uc |= BIT(port);
+		else
+			uc &= ~BIT(port);
+		b53_write16(dev, B53_CTRL_PAGE, B53_UC_FLOOD_MASK, uc);
+	}
 }
 
 static void b53_port_set_mcast_flood(struct b53_device *dev, int port,
@@ -559,19 +589,31 @@ static void b53_port_set_mcast_flood(struct b53_device *dev, int port,
 {
 	u16 mc;
 
-	b53_read16(dev, B53_CTRL_PAGE, B53_MC_FLOOD_MASK, &mc);
-	if (multicast)
-		mc |= BIT(port);
-	else
-		mc &= ~BIT(port);
-	b53_write16(dev, B53_CTRL_PAGE, B53_MC_FLOOD_MASK, mc);
+	if (is5325(dev)) {
+		if (port == B53_CPU_PORT_25)
+			port = B53_CPU_PORT;
 
-	b53_read16(dev, B53_CTRL_PAGE, B53_IPMC_FLOOD_MASK, &mc);
-	if (multicast)
-		mc |= BIT(port);
-	else
-		mc &= ~BIT(port);
-	b53_write16(dev, B53_CTRL_PAGE, B53_IPMC_FLOOD_MASK, mc);
+		b53_read16(dev, B53_IEEE_PAGE, B53_IEEE_MCAST_DLF, &mc);
+		if (multicast)
+			mc |= BIT(port) | B53_IEEE_MCAST_DROP_EN;
+		else
+			mc &= ~BIT(port);
+		b53_write16(dev, B53_IEEE_PAGE, B53_IEEE_MCAST_DLF, mc);
+	} else {
+		b53_read16(dev, B53_CTRL_PAGE, B53_MC_FLOOD_MASK, &mc);
+		if (multicast)
+			mc |= BIT(port);
+		else
+			mc &= ~BIT(port);
+		b53_write16(dev, B53_CTRL_PAGE, B53_MC_FLOOD_MASK, mc);
+
+		b53_read16(dev, B53_CTRL_PAGE, B53_IPMC_FLOOD_MASK, &mc);
+		if (multicast)
+			mc |= BIT(port);
+		else
+			mc &= ~BIT(port);
+		b53_write16(dev, B53_CTRL_PAGE, B53_IPMC_FLOOD_MASK, mc);
+	}
 }
 
 static void b53_port_set_learning(struct b53_device *dev, int port,
@@ -579,6 +621,9 @@ static void b53_port_set_learning(struct b53_device *dev, int port,
 {
 	u16 reg;
 
+	if (is5325(dev))
+		return;
+
 	b53_read16(dev, B53_CTRL_PAGE, B53_DIS_LEARNING, &reg);
 	if (learning)
 		reg &= ~BIT(port);
@@ -615,6 +660,19 @@ int b53_setup_port(struct dsa_switch *ds, int port)
 	if (dsa_is_user_port(ds, port))
 		b53_set_eap_mode(dev, port, EAP_MODE_SIMPLIFIED);
 
+	if (is5325(dev) &&
+	    in_range(port, 1, 4)) {
+		u8 reg;
+
+		b53_read8(dev, B53_CTRL_PAGE, B53_PD_MODE_CTRL_25, &reg);
+		reg &= ~PD_MODE_POWER_DOWN_PORT(0);
+		if (dsa_is_unused_port(ds, port))
+			reg |= PD_MODE_POWER_DOWN_PORT(port);
+		else
+			reg &= ~PD_MODE_POWER_DOWN_PORT(port);
+		b53_write8(dev, B53_CTRL_PAGE, B53_PD_MODE_CTRL_25, reg);
+	}
+
 	return 0;
 }
 EXPORT_SYMBOL(b53_setup_port);
@@ -713,6 +771,11 @@ void b53_brcm_hdr_setup(struct dsa_switch *ds, int port)
 		hdr_ctl |= GC_FRM_MGMT_PORT_M;
 	b53_write8(dev, B53_MGMT_PAGE, B53_GLOBAL_CONFIG, hdr_ctl);
 
+	/* B53_BRCM_HDR not present on devices with legacy tags */
+	if (dev->tag_protocol == DSA_TAG_PROTO_BRCM_LEGACY ||
+	    dev->tag_protocol == DSA_TAG_PROTO_BRCM_LEGACY_FCS)
+		return;
+
 	/* Enable Broadcom tags for IMP port */
 	b53_read8(dev, B53_MGMT_PAGE, B53_BRCM_HDR, &hdr_ctl);
 	if (tag_en)
@@ -1257,6 +1320,8 @@ static void b53_force_link(struct b53_device *dev, int port, int link)
 	if (port == dev->imp_port) {
 		off = B53_PORT_OVERRIDE_CTRL;
 		val = PORT_OVERRIDE_EN;
+	} else if (is5325(dev)) {
+		return;
 	} else {
 		off = B53_GMII_PORT_OVERRIDE_CTRL(port);
 		val = GMII_PO_EN;
@@ -1281,6 +1346,8 @@ static void b53_force_port_config(struct b53_device *dev, int port,
 	if (port == dev->imp_port) {
 		off = B53_PORT_OVERRIDE_CTRL;
 		val = PORT_OVERRIDE_EN;
+	} else if (is5325(dev)) {
+		return;
 	} else {
 		off = B53_GMII_PORT_OVERRIDE_CTRL(port);
 		val = GMII_PO_EN;
@@ -1311,10 +1378,19 @@ static void b53_force_port_config(struct b53_device *dev, int port,
 		return;
 	}
 
-	if (rx_pause)
-		reg |= PORT_OVERRIDE_RX_FLOW;
-	if (tx_pause)
-		reg |= PORT_OVERRIDE_TX_FLOW;
+	if (rx_pause) {
+		if (is5325(dev))
+			reg |= PORT_OVERRIDE_LP_FLOW_25;
+		else
+			reg |= PORT_OVERRIDE_RX_FLOW;
+	}
+
+	if (tx_pause) {
+		if (is5325(dev))
+			reg |= PORT_OVERRIDE_LP_FLOW_25;
+		else
+			reg |= PORT_OVERRIDE_TX_FLOW;
+	}
 
 	b53_write8(dev, B53_CTRL_PAGE, off, reg);
 }
@@ -1764,6 +1840,45 @@ static int b53_arl_read(struct b53_device *dev, u64 mac,
 	return *idx >= dev->num_arl_bins ? -ENOSPC : -ENOENT;
 }
 
+static int b53_arl_read_25(struct b53_device *dev, u64 mac,
+			   u16 vid, struct b53_arl_entry *ent, u8 *idx)
+{
+	DECLARE_BITMAP(free_bins, B53_ARLTBL_MAX_BIN_ENTRIES);
+	unsigned int i;
+	int ret;
+
+	ret = b53_arl_op_wait(dev);
+	if (ret)
+		return ret;
+
+	bitmap_zero(free_bins, dev->num_arl_bins);
+
+	/* Read the bins */
+	for (i = 0; i < dev->num_arl_bins; i++) {
+		u64 mac_vid;
+
+		b53_read64(dev, B53_ARLIO_PAGE,
+			   B53_ARLTBL_MAC_VID_ENTRY(i), &mac_vid);
+
+		b53_arl_to_entry_25(ent, mac_vid);
+
+		if (!(mac_vid & ARLTBL_VALID_25)) {
+			set_bit(i, free_bins);
+			continue;
+		}
+		if ((mac_vid & ARLTBL_MAC_MASK) != mac)
+			continue;
+		if (dev->vlan_enabled &&
+		    ((mac_vid >> ARLTBL_VID_S_65) & ARLTBL_VID_MASK_25) != vid)
+			continue;
+		*idx = i;
+		return 0;
+	}
+
+	*idx = find_first_bit(free_bins, dev->num_arl_bins);
+	return *idx >= dev->num_arl_bins ? -ENOSPC : -ENOENT;
+}
+
 static int b53_arl_op(struct b53_device *dev, int op, int port,
 		      const unsigned char *addr, u16 vid, bool is_valid)
 {
@@ -1778,14 +1893,18 @@ static int b53_arl_op(struct b53_device *dev, int op, int port,
 
 	/* Perform a read for the given MAC and VID */
 	b53_write48(dev, B53_ARLIO_PAGE, B53_MAC_ADDR_IDX, mac);
-	b53_write16(dev, B53_ARLIO_PAGE, B53_VLAN_ID_IDX, vid);
+	if (!is5325m(dev))
+		b53_write16(dev, B53_ARLIO_PAGE, B53_VLAN_ID_IDX, vid);
 
 	/* Issue a read operation for this MAC */
 	ret = b53_arl_rw_op(dev, 1);
 	if (ret)
 		return ret;
 
-	ret = b53_arl_read(dev, mac, vid, &ent, &idx);
+	if (is5325(dev) || is5365(dev))
+		ret = b53_arl_read_25(dev, mac, vid, &ent, &idx);
+	else
+		ret = b53_arl_read(dev, mac, vid, &ent, &idx);
 
 	/* If this is a read, just finish now */
 	if (op)
@@ -1829,12 +1948,17 @@ static int b53_arl_op(struct b53_device *dev, int op, int port,
 	ent.is_static = true;
 	ent.is_age = false;
 	memcpy(ent.mac, addr, ETH_ALEN);
-	b53_arl_from_entry(&mac_vid, &fwd_entry, &ent);
+	if (is5325(dev) || is5365(dev))
+		b53_arl_from_entry_25(&mac_vid, &ent);
+	else
+		b53_arl_from_entry(&mac_vid, &fwd_entry, &ent);
 
 	b53_write64(dev, B53_ARLIO_PAGE,
 		    B53_ARLTBL_MAC_VID_ENTRY(idx), mac_vid);
-	b53_write32(dev, B53_ARLIO_PAGE,
-		    B53_ARLTBL_DATA_ENTRY(idx), fwd_entry);
+
+	if (!is5325(dev) && !is5365(dev))
+		b53_write32(dev, B53_ARLIO_PAGE,
+			    B53_ARLTBL_DATA_ENTRY(idx), fwd_entry);
 
 	return b53_arl_rw_op(dev, 0);
 }
@@ -1846,12 +1970,6 @@ int b53_fdb_add(struct dsa_switch *ds, int port,
 	struct b53_device *priv = ds->priv;
 	int ret;
 
-	/* 5325 and 5365 require some more massaging, but could
-	 * be supported eventually
-	 */
-	if (is5325(priv) || is5365(priv))
-		return -EOPNOTSUPP;
-
 	mutex_lock(&priv->arl_mutex);
 	ret = b53_arl_op(priv, 0, port, addr, vid, true);
 	mutex_unlock(&priv->arl_mutex);
@@ -1878,10 +1996,15 @@ EXPORT_SYMBOL(b53_fdb_del);
 static int b53_arl_search_wait(struct b53_device *dev)
 {
 	unsigned int timeout = 1000;
-	u8 reg;
+	u8 reg, offset;
+
+	if (is5325(dev) || is5365(dev))
+		offset = B53_ARL_SRCH_CTL_25;
+	else
+		offset = B53_ARL_SRCH_CTL;
 
 	do {
-		b53_read8(dev, B53_ARLIO_PAGE, B53_ARL_SRCH_CTL, &reg);
+		b53_read8(dev, B53_ARLIO_PAGE, offset, &reg);
 		if (!(reg & ARL_SRCH_STDN))
 			return 0;
 
@@ -1898,13 +2021,24 @@ static void b53_arl_search_rd(struct b53_device *dev, u8 idx,
 			      struct b53_arl_entry *ent)
 {
 	u64 mac_vid;
-	u32 fwd_entry;
 
-	b53_read64(dev, B53_ARLIO_PAGE,
-		   B53_ARL_SRCH_RSTL_MACVID(idx), &mac_vid);
-	b53_read32(dev, B53_ARLIO_PAGE,
-		   B53_ARL_SRCH_RSTL(idx), &fwd_entry);
-	b53_arl_to_entry(ent, mac_vid, fwd_entry);
+	if (is5325(dev)) {
+		b53_read64(dev, B53_ARLIO_PAGE, B53_ARL_SRCH_RSTL_0_MACVID_25,
+			   &mac_vid);
+		b53_arl_to_entry_25(ent, mac_vid);
+	} else if (is5365(dev)) {
+		b53_read64(dev, B53_ARLIO_PAGE, B53_ARL_SRCH_RSTL_0_MACVID_65,
+			   &mac_vid);
+		b53_arl_to_entry_25(ent, mac_vid);
+	} else {
+		u32 fwd_entry;
+
+		b53_read64(dev, B53_ARLIO_PAGE, B53_ARL_SRCH_RSTL_MACVID(idx),
+			   &mac_vid);
+		b53_read32(dev, B53_ARLIO_PAGE, B53_ARL_SRCH_RSTL(idx),
+			   &fwd_entry);
+		b53_arl_to_entry(ent, mac_vid, fwd_entry);
+	}
 }
 
 static int b53_fdb_copy(int port, const struct b53_arl_entry *ent,
@@ -1925,14 +2059,20 @@ int b53_fdb_dump(struct dsa_switch *ds, int port,
 	struct b53_device *priv = ds->priv;
 	struct b53_arl_entry results[2];
 	unsigned int count = 0;
+	u8 offset;
 	int ret;
 	u8 reg;
 
 	mutex_lock(&priv->arl_mutex);
 
+	if (is5325(priv) || is5365(priv))
+		offset = B53_ARL_SRCH_CTL_25;
+	else
+		offset = B53_ARL_SRCH_CTL;
+
 	/* Start search operation */
 	reg = ARL_SRCH_STDN;
-	b53_write8(priv, B53_ARLIO_PAGE, B53_ARL_SRCH_CTL, reg);
+	b53_write8(priv, offset, B53_ARL_SRCH_CTL, reg);
 
 	do {
 		ret = b53_arl_search_wait(priv);
@@ -2165,7 +2305,13 @@ int b53_br_flags_pre(struct dsa_switch *ds, int port,
 		     struct switchdev_brport_flags flags,
 		     struct netlink_ext_ack *extack)
 {
-	if (flags.mask & ~(BR_FLOOD | BR_MCAST_FLOOD | BR_LEARNING))
+	struct b53_device *dev = ds->priv;
+	unsigned long mask = (BR_FLOOD | BR_MCAST_FLOOD);
+
+	if (!is5325(dev))
+		mask |= BR_LEARNING;
+
+	if (flags.mask & ~mask)
 		return -EINVAL;
 
 	return 0;
@@ -2241,8 +2387,11 @@ enum dsa_tag_protocol b53_get_tag_protocol(struct dsa_switch *ds, int port,
 		goto out;
 	}
 
-	/* Older models require a different 6 byte tag */
-	if (is5325(dev) || is5365(dev) || is63xx(dev)) {
+	/* Older models require different 6 byte tags */
+	if (is5325(dev) || is5365(dev)) {
+		dev->tag_protocol = DSA_TAG_PROTO_BRCM_LEGACY_FCS;
+		goto out;
+	} else if (is63xx(dev)) {
 		dev->tag_protocol = DSA_TAG_PROTO_BRCM_LEGACY;
 		goto out;
 	}
@@ -2830,6 +2979,9 @@ static int b53_switch_init(struct b53_device *dev)
 		}
 	}
 
+	if (is5325e(dev))
+		dev->num_arl_buckets = 512;
+
 	dev->num_ports = fls(dev->enabled_ports);
 
 	dev->ds->num_ports = min_t(unsigned int, dev->num_ports, DSA_MAX_PORTS);
@@ -2931,10 +3083,24 @@ int b53_switch_detect(struct b53_device *dev)
 		b53_write16(dev, B53_VLAN_PAGE, B53_VLAN_TABLE_ACCESS_25, 0xf);
 		b53_read16(dev, B53_VLAN_PAGE, B53_VLAN_TABLE_ACCESS_25, &tmp);
 
-		if (tmp == 0xf)
+		if (tmp == 0xf) {
+			u32 phy_id;
+			int val;
+
 			dev->chip_id = BCM5325_DEVICE_ID;
-		else
+
+			val = b53_phy_read16(dev->ds, 0, MII_PHYSID1);
+			phy_id = (val & 0xffff) << 16;
+			val = b53_phy_read16(dev->ds, 0, MII_PHYSID2);
+			phy_id |= (val & 0xfff0);
+
+			if (phy_id == 0x00406330)
+				dev->variant_id = B53_VARIANT_5325M;
+			else if (phy_id == 0x0143bc30)
+				dev->variant_id = B53_VARIANT_5325E;
+		} else {
 			dev->chip_id = BCM5365_DEVICE_ID;
+		}
 		break;
 	case BCM5389_DEVICE_ID:
 	case BCM5395_DEVICE_ID:
diff --git a/drivers/net/dsa/b53/b53_priv.h b/drivers/net/dsa/b53/b53_priv.h
index a5ef7071ba07..b1b9e8882ba4 100644
--- a/drivers/net/dsa/b53/b53_priv.h
+++ b/drivers/net/dsa/b53/b53_priv.h
@@ -84,6 +84,12 @@ enum {
 	BCM53134_DEVICE_ID = 0x5075,
 };
 
+enum b53_variant_id {
+	B53_VARIANT_NONE = 0,
+	B53_VARIANT_5325E,
+	B53_VARIANT_5325M,
+};
+
 struct b53_pcs {
 	struct phylink_pcs pcs;
 	struct b53_device *dev;
@@ -118,6 +124,7 @@ struct b53_device {
 
 	/* chip specific data */
 	u32 chip_id;
+	enum b53_variant_id variant_id;
 	u8 core_rev;
 	u8 vta_regs[3];
 	u8 duplex_reg;
@@ -165,6 +172,18 @@ static inline int is5325(struct b53_device *dev)
 	return dev->chip_id == BCM5325_DEVICE_ID;
 }
 
+static inline int is5325e(struct b53_device *dev)
+{
+	return is5325(dev) &&
+		dev->variant_id == B53_VARIANT_5325E;
+}
+
+static inline int is5325m(struct b53_device *dev)
+{
+	return is5325(dev) &&
+		dev->variant_id == B53_VARIANT_5325M;
+}
+
 static inline int is5365(struct b53_device *dev)
 {
 #ifdef CONFIG_BCM47XX
@@ -298,6 +317,19 @@ static inline void b53_arl_to_entry(struct b53_arl_entry *ent,
 	ent->vid = mac_vid >> ARLTBL_VID_S;
 }
 
+static inline void b53_arl_to_entry_25(struct b53_arl_entry *ent,
+				       u64 mac_vid)
+{
+	memset(ent, 0, sizeof(*ent));
+	ent->port = (mac_vid >> ARLTBL_DATA_PORT_ID_S_25) &
+		     ARLTBL_DATA_PORT_ID_MASK_25;
+	ent->is_valid = !!(mac_vid & ARLTBL_VALID_25);
+	ent->is_age = !!(mac_vid & ARLTBL_AGE_25);
+	ent->is_static = !!(mac_vid & ARLTBL_STATIC_25);
+	u64_to_ether_addr(mac_vid, ent->mac);
+	ent->vid = mac_vid >> ARLTBL_VID_S_65;
+}
+
 static inline void b53_arl_from_entry(u64 *mac_vid, u32 *fwd_entry,
 				      const struct b53_arl_entry *ent)
 {
@@ -312,6 +344,22 @@ static inline void b53_arl_from_entry(u64 *mac_vid, u32 *fwd_entry,
 		*fwd_entry |= ARLTBL_AGE;
 }
 
+static inline void b53_arl_from_entry_25(u64 *mac_vid,
+					 const struct b53_arl_entry *ent)
+{
+	*mac_vid = ether_addr_to_u64(ent->mac);
+	*mac_vid |= (u64)(ent->port & ARLTBL_DATA_PORT_ID_MASK_25) <<
+			  ARLTBL_DATA_PORT_ID_S_25;
+	*mac_vid |= (u64)(ent->vid & ARLTBL_VID_MASK_25) <<
+			  ARLTBL_VID_S_65;
+	if (ent->is_valid)
+		*mac_vid |= ARLTBL_VALID_25;
+	if (ent->is_static)
+		*mac_vid |= ARLTBL_STATIC_25;
+	if (ent->is_age)
+		*mac_vid |= ARLTBL_AGE_25;
+}
+
 #ifdef CONFIG_BCM47XX
 
 #include <linux/bcm47xx_nvram.h>
diff --git a/drivers/net/dsa/b53/b53_regs.h b/drivers/net/dsa/b53/b53_regs.h
index 1fbc5a204bc7..309fe0e46dad 100644
--- a/drivers/net/dsa/b53/b53_regs.h
+++ b/drivers/net/dsa/b53/b53_regs.h
@@ -29,6 +29,7 @@
 #define B53_ARLIO_PAGE			0x05 /* ARL Access */
 #define B53_FRAMEBUF_PAGE		0x06 /* Management frame access */
 #define B53_MEM_ACCESS_PAGE		0x08 /* Memory access */
+#define B53_IEEE_PAGE			0x0a /* IEEE 802.1X */
 
 /* PHY Registers */
 #define B53_PORT_MII_PAGE(i)		(0x10 + (i)) /* Port i MII Registers */
@@ -95,17 +96,22 @@
 #define   PORT_OVERRIDE_SPEED_10M	(0 << PORT_OVERRIDE_SPEED_S)
 #define   PORT_OVERRIDE_SPEED_100M	(1 << PORT_OVERRIDE_SPEED_S)
 #define   PORT_OVERRIDE_SPEED_1000M	(2 << PORT_OVERRIDE_SPEED_S)
+#define   PORT_OVERRIDE_LP_FLOW_25	BIT(3) /* BCM5325 only */
 #define   PORT_OVERRIDE_RV_MII_25	BIT(4) /* BCM5325 only */
 #define   PORT_OVERRIDE_RX_FLOW		BIT(4)
 #define   PORT_OVERRIDE_TX_FLOW		BIT(5)
 #define   PORT_OVERRIDE_SPEED_2000M	BIT(6) /* BCM5301X only, requires setting 1000M */
 #define   PORT_OVERRIDE_EN		BIT(7) /* Use the register contents */
 
-/* Power-down mode control */
+/* Power-down mode control (8 bit) */
 #define B53_PD_MODE_CTRL_25		0x0f
+#define  PD_MODE_PORT_MASK		0x1f
+/* Bit 0 also powers down the switch. */
+#define  PD_MODE_POWER_DOWN_PORT(i)	BIT(i)
 
 /* 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_UC_FWD_EN			BIT(6)
 #define  B53_MC_FWD_EN			BIT(7)
@@ -324,9 +330,10 @@
 #define   ARLTBL_VID_MASK		0xfff
 #define   ARLTBL_DATA_PORT_ID_S_25	48
 #define   ARLTBL_DATA_PORT_ID_MASK_25	0xf
-#define   ARLTBL_AGE_25			BIT(61)
-#define   ARLTBL_STATIC_25		BIT(62)
-#define   ARLTBL_VALID_25		BIT(63)
+#define   ARLTBL_VID_S_65		53
+#define   ARLTBL_AGE_25			BIT_ULL(61)
+#define   ARLTBL_STATIC_25		BIT_ULL(62)
+#define   ARLTBL_VALID_25		BIT_ULL(63)
 
 /* ARL Table Data Entry N Registers (32 bit) */
 #define B53_ARLTBL_DATA_ENTRY(n)	((0x10 * (n)) + 0x18)
@@ -366,6 +373,18 @@
 #define B53_ARL_SRCH_RSTL(x)		(B53_ARL_SRCH_RSTL_0 + ((x) * 0x10))
 
 /*************************************************************************
+ * IEEE 802.1X Registers
+ *************************************************************************/
+
+/* Multicast DLF Drop Control register (16 bit) */
+#define B53_IEEE_MCAST_DLF		0x94
+#define B53_IEEE_MCAST_DROP_EN		BIT(11)
+
+/* Unicast DLF Drop Control register (16 bit) */
+#define B53_IEEE_UCAST_DLF		0x96
+#define B53_IEEE_UCAST_DROP_EN		BIT(11)
+
+/*************************************************************************
  * Port VLAN Registers
  *************************************************************************/
 
diff --git a/include/net/dsa.h b/include/net/dsa.h
index 55e2d97f247e..d73ea0880066 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -54,11 +54,13 @@ struct tc_action;
 #define DSA_TAG_PROTO_RZN1_A5PSW_VALUE		26
 #define DSA_TAG_PROTO_LAN937X_VALUE		27
 #define DSA_TAG_PROTO_VSC73XX_8021Q_VALUE	28
+#define DSA_TAG_PROTO_BRCM_LEGACY_FCS_VALUE	29
 
 enum dsa_tag_protocol {
 	DSA_TAG_PROTO_NONE		= DSA_TAG_PROTO_NONE_VALUE,
 	DSA_TAG_PROTO_BRCM		= DSA_TAG_PROTO_BRCM_VALUE,
 	DSA_TAG_PROTO_BRCM_LEGACY	= DSA_TAG_PROTO_BRCM_LEGACY_VALUE,
+	DSA_TAG_PROTO_BRCM_LEGACY_FCS	= DSA_TAG_PROTO_BRCM_LEGACY_FCS_VALUE,
 	DSA_TAG_PROTO_BRCM_PREPEND	= DSA_TAG_PROTO_BRCM_PREPEND_VALUE,
 	DSA_TAG_PROTO_DSA		= DSA_TAG_PROTO_DSA_VALUE,
 	DSA_TAG_PROTO_EDSA		= DSA_TAG_PROTO_EDSA_VALUE,
diff --git a/net/dsa/Kconfig b/net/dsa/Kconfig
index 2dfe9063613f..869cbe57162f 100644
--- a/net/dsa/Kconfig
+++ b/net/dsa/Kconfig
@@ -42,12 +42,24 @@ config NET_DSA_TAG_BRCM
 	  Broadcom switches which place the tag after the MAC source address.
 
 config NET_DSA_TAG_BRCM_LEGACY
-	tristate "Tag driver for Broadcom legacy switches using in-frame headers"
+	tristate "Tag driver for BCM63xx legacy switches using in-frame headers"
 	select NET_DSA_TAG_BRCM_COMMON
 	help
 	  Say Y if you want to enable support for tagging frames for the
-	  Broadcom legacy switches which place the tag after the MAC source
+	  BCM63xx legacy switches which place the tag after the MAC source
 	  address.
+	  This tag is used in BCM63xx legacy switches which work without the
+	  original FCS and length before the tag insertion.
+
+config NET_DSA_TAG_BRCM_LEGACY_FCS
+	tristate "Tag driver for BCM53xx legacy switches using in-frame headers"
+	select NET_DSA_TAG_BRCM_COMMON
+	help
+	  Say Y if you want to enable support for tagging frames for the
+	  BCM53xx legacy switches which place the tag after the MAC source
+	  address.
+	  This tag is used in BCM53xx legacy switches which expect original
+	  FCS and length before the tag insertion to be present.
 
 config NET_DSA_TAG_BRCM_PREPEND
 	tristate "Tag driver for Broadcom switches using prepended headers"
diff --git a/net/dsa/tag_brcm.c b/net/dsa/tag_brcm.c
index fe75821623a4..26bb657ceac3 100644
--- a/net/dsa/tag_brcm.c
+++ b/net/dsa/tag_brcm.c
@@ -15,6 +15,7 @@
 
 #define BRCM_NAME		"brcm"
 #define BRCM_LEGACY_NAME	"brcm-legacy"
+#define BRCM_LEGACY_FCS_NAME	"brcm-legacy-fcs"
 #define BRCM_PREPEND_NAME	"brcm-prepend"
 
 /* Legacy Broadcom tag (6 bytes) */
@@ -32,6 +33,10 @@
 #define BRCM_LEG_MULTICAST	(1 << 5)
 #define BRCM_LEG_EGRESS		(2 << 5)
 #define BRCM_LEG_INGRESS	(3 << 5)
+#define BRCM_LEG_LEN_HI(x)	(((x) >> 8) & 0x7)
+
+/* 4th byte in the tag */
+#define BRCM_LEG_LEN_LO(x)	((x) & 0xff)
 
 /* 6th byte in the tag */
 #define BRCM_LEG_PORT_ID	(0xf)
@@ -212,6 +217,41 @@ DSA_TAG_DRIVER(brcm_netdev_ops);
 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM, BRCM_NAME);
 #endif
 
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY) || \
+	IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY_FCS)
+static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
+					struct net_device *dev)
+{
+	int len = BRCM_LEG_TAG_LEN;
+	int source_port;
+	u8 *brcm_tag;
+
+	if (unlikely(!pskb_may_pull(skb, BRCM_LEG_TAG_LEN + VLAN_HLEN)))
+		return NULL;
+
+	brcm_tag = dsa_etype_header_pos_rx(skb);
+
+	source_port = brcm_tag[5] & BRCM_LEG_PORT_ID;
+
+	skb->dev = dsa_conduit_find_user(dev, 0, source_port);
+	if (!skb->dev)
+		return NULL;
+
+	/* VLAN tag is added by BCM63xx internal switch */
+	if (netdev_uses_dsa(skb->dev))
+		len += VLAN_HLEN;
+
+	/* Remove Broadcom tag and update checksum */
+	skb_pull_rcsum(skb, len);
+
+	dsa_default_offload_fwd_mark(skb);
+
+	dsa_strip_etype_header(skb, len);
+
+	return skb;
+}
+#endif /* CONFIG_NET_DSA_TAG_BRCM_LEGACY || CONFIG_NET_DSA_TAG_BRCM_LEGACY_FCS */
+
 #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY)
 static struct sk_buff *brcm_leg_tag_xmit(struct sk_buff *skb,
 					 struct net_device *dev)
@@ -250,49 +290,77 @@ static struct sk_buff *brcm_leg_tag_xmit(struct sk_buff *skb,
 	return skb;
 }
 
-static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
-					struct net_device *dev)
+static const struct dsa_device_ops brcm_legacy_netdev_ops = {
+	.name = BRCM_LEGACY_NAME,
+	.proto = DSA_TAG_PROTO_BRCM_LEGACY,
+	.xmit = brcm_leg_tag_xmit,
+	.rcv = brcm_leg_tag_rcv,
+	.needed_headroom = BRCM_LEG_TAG_LEN,
+};
+
+DSA_TAG_DRIVER(brcm_legacy_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM_LEGACY, BRCM_LEGACY_NAME);
+#endif /* CONFIG_NET_DSA_TAG_BRCM_LEGACY */
+
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY_FCS)
+static struct sk_buff *brcm_leg_fcs_tag_xmit(struct sk_buff *skb,
+					     struct net_device *dev)
 {
-	int len = BRCM_LEG_TAG_LEN;
-	int source_port;
+	struct dsa_port *dp = dsa_user_to_port(dev);
+	unsigned int fcs_len;
+	__le32 fcs_val;
 	u8 *brcm_tag;
 
-	if (unlikely(!pskb_may_pull(skb, BRCM_LEG_TAG_LEN + VLAN_HLEN)))
+	/* The Ethernet switch we are interfaced with needs packets to be at
+	 * least 64 bytes (including FCS) otherwise they will be discarded when
+	 * they enter the switch port logic. When Broadcom tags are enabled, we
+	 * need to make sure that packets are at least 70 bytes (including FCS
+	 * and tag) because the length verification is done after the Broadcom
+	 * tag is stripped off the ingress packet.
+	 *
+	 * Let dsa_user_xmit() free the SKB.
+	 */
+	if (__skb_put_padto(skb, ETH_ZLEN + BRCM_LEG_TAG_LEN, false))
 		return NULL;
 
-	brcm_tag = dsa_etype_header_pos_rx(skb);
+	fcs_len = skb->len;
+	fcs_val = cpu_to_le32(crc32_le(~0, skb->data, fcs_len) ^ ~0);
 
-	source_port = brcm_tag[5] & BRCM_LEG_PORT_ID;
+	skb_push(skb, BRCM_LEG_TAG_LEN);
 
-	skb->dev = dsa_conduit_find_user(dev, 0, source_port);
-	if (!skb->dev)
-		return NULL;
+	dsa_alloc_etype_header(skb, BRCM_LEG_TAG_LEN);
 
-	/* VLAN tag is added by BCM63xx internal switch */
-	if (netdev_uses_dsa(skb->dev))
-		len += VLAN_HLEN;
+	brcm_tag = skb->data + 2 * ETH_ALEN;
 
-	/* Remove Broadcom tag and update checksum */
-	skb_pull_rcsum(skb, len);
+	/* Broadcom tag type */
+	brcm_tag[0] = BRCM_LEG_TYPE_HI;
+	brcm_tag[1] = BRCM_LEG_TYPE_LO;
 
-	dsa_default_offload_fwd_mark(skb);
+	/* Broadcom tag value */
+	brcm_tag[2] = BRCM_LEG_EGRESS | BRCM_LEG_LEN_HI(fcs_len);
+	brcm_tag[3] = BRCM_LEG_LEN_LO(fcs_len);
+	brcm_tag[4] = 0;
+	brcm_tag[5] = dp->index & BRCM_LEG_PORT_ID;
 
-	dsa_strip_etype_header(skb, len);
+	/* Original FCS value */
+	if (__skb_pad(skb, ETH_FCS_LEN, false))
+		return NULL;
+	skb_put_data(skb, &fcs_val, ETH_FCS_LEN);
 
 	return skb;
 }
 
-static const struct dsa_device_ops brcm_legacy_netdev_ops = {
-	.name = BRCM_LEGACY_NAME,
-	.proto = DSA_TAG_PROTO_BRCM_LEGACY,
-	.xmit = brcm_leg_tag_xmit,
+static const struct dsa_device_ops brcm_legacy_fcs_netdev_ops = {
+	.name = BRCM_LEGACY_FCS_NAME,
+	.proto = DSA_TAG_PROTO_BRCM_LEGACY_FCS,
+	.xmit = brcm_leg_fcs_tag_xmit,
 	.rcv = brcm_leg_tag_rcv,
 	.needed_headroom = BRCM_LEG_TAG_LEN,
 };
 
-DSA_TAG_DRIVER(brcm_legacy_netdev_ops);
-MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM_LEGACY, BRCM_LEGACY_NAME);
-#endif /* CONFIG_NET_DSA_TAG_BRCM_LEGACY */
+DSA_TAG_DRIVER(brcm_legacy_fcs_netdev_ops);
+MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM_LEGACY_FCS, BRCM_LEGACY_FCS_NAME);
+#endif /* CONFIG_NET_DSA_TAG_BRCM_LEGACY_FCS */
 
 #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_PREPEND)
 static struct sk_buff *brcm_tag_xmit_prepend(struct sk_buff *skb,
@@ -328,6 +396,9 @@ static struct dsa_tag_driver *dsa_tag_driver_array[] =	{
 #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY)
 	&DSA_TAG_DRIVER_NAME(brcm_legacy_netdev_ops),
 #endif
+#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY_FCS)
+	&DSA_TAG_DRIVER_NAME(brcm_legacy_fcs_netdev_ops),
+#endif
 #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_PREPEND)
 	&DSA_TAG_DRIVER_NAME(brcm_prepend_netdev_ops),
 #endif