net: dsa: bcm_sf2: Implement FDB operations

Add support for the FDB add, delete, and dump operations. The add and
delete operations are implemented using directed ARL operations using
the specified MAC address and consist in a read operation, write and
readback operation.

The dump operation consists in using the ARL search and software
filtering entries which are not for the desired port.
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/dsa/bcm_sf2.c

@@ -25,6 +25,8 @@
 #include <linux/ethtool.h>
 #include <linux/if_bridge.h>
 #include <linux/brcmphy.h>
+#include <linux/etherdevice.h>
+#include <net/switchdev.h>
 
 #include "bcm_sf2.h"
 #include "bcm_sf2_regs.h"
@@ -555,6 +557,236 @@ static int bcm_sf2_sw_br_set_stp_state(struct dsa_switch *ds, int port,
 	return 0;
 }
 
+/* Address Resolution Logic routines */
+static int bcm_sf2_arl_op_wait(struct bcm_sf2_priv *priv)
+{
+	unsigned int timeout = 10;
+	u32 reg;
+
+	do {
+		reg = core_readl(priv, CORE_ARLA_RWCTL);
+		if (!(reg & ARL_STRTDN))
+			return 0;
+
+		usleep_range(1000, 2000);
+	} while (timeout--);
+
+	return -ETIMEDOUT;
+}
+
+static int bcm_sf2_arl_rw_op(struct bcm_sf2_priv *priv, unsigned int op)
+{
+	u32 cmd;
+
+	if (op > ARL_RW)
+		return -EINVAL;
+
+	cmd = core_readl(priv, CORE_ARLA_RWCTL);
+	cmd &= ~IVL_SVL_SELECT;
+	cmd |= ARL_STRTDN;
+	if (op)
+		cmd |= ARL_RW;
+	else
+		cmd &= ~ARL_RW;
+	core_writel(priv, cmd, CORE_ARLA_RWCTL);
+
+	return bcm_sf2_arl_op_wait(priv);
+}
+
+static int bcm_sf2_arl_read(struct bcm_sf2_priv *priv, u64 mac,
+			    u16 vid, struct bcm_sf2_arl_entry *ent, u8 *idx,
+			    bool is_valid)
+{
+	unsigned int i;
+	int ret;
+
+	ret = bcm_sf2_arl_op_wait(priv);
+	if (ret)
+		return ret;
+
+	/* Read the 4 bins */
+	for (i = 0; i < 4; i++) {
+		u64 mac_vid;
+		u32 fwd_entry;
+
+		mac_vid = core_readq(priv, CORE_ARLA_MACVID_ENTRY(i));
+		fwd_entry = core_readl(priv, CORE_ARLA_FWD_ENTRY(i));
+		bcm_sf2_arl_to_entry(ent, mac_vid, fwd_entry);
+
+		if (ent->is_valid && is_valid) {
+			*idx = i;
+			return 0;
+		}
+
+		/* This is the MAC we just deleted */
+		if (!is_valid && (mac_vid & mac))
+			return 0;
+	}
+
+	return -ENOENT;
+}
+
+static int bcm_sf2_arl_op(struct bcm_sf2_priv *priv, int op, int port,
+			  const unsigned char *addr, u16 vid, bool is_valid)
+{
+	struct bcm_sf2_arl_entry ent;
+	u32 fwd_entry;
+	u64 mac, mac_vid = 0;
+	u8 idx = 0;
+	int ret;
+
+	/* Convert the array into a 64-bit MAC */
+	mac = bcm_sf2_mac_to_u64(addr);
+
+	/* Perform a read for the given MAC and VID */
+	core_writeq(priv, mac, CORE_ARLA_MAC);
+	core_writel(priv, vid, CORE_ARLA_VID);
+
+	/* Issue a read operation for this MAC */
+	ret = bcm_sf2_arl_rw_op(priv, 1);
+	if (ret)
+		return ret;
+
+	ret = bcm_sf2_arl_read(priv, mac, vid, &ent, &idx, is_valid);
+	/* If this is a read, just finish now */
+	if (op)
+		return ret;
+
+	/* We could not find a matching MAC, so reset to a new entry */
+	if (ret) {
+		fwd_entry = 0;
+		idx = 0;
+	}
+
+	memset(&ent, 0, sizeof(ent));
+	ent.port = port;
+	ent.is_valid = is_valid;
+	ent.vid = vid;
+	ent.is_static = true;
+	memcpy(ent.mac, addr, ETH_ALEN);
+	bcm_sf2_arl_from_entry(&mac_vid, &fwd_entry, &ent);
+
+	core_writeq(priv, mac_vid, CORE_ARLA_MACVID_ENTRY(idx));
+	core_writel(priv, fwd_entry, CORE_ARLA_FWD_ENTRY(idx));
+
+	ret = bcm_sf2_arl_rw_op(priv, 0);
+	if (ret)
+		return ret;
+
+	/* Re-read the entry to check */
+	return bcm_sf2_arl_read(priv, mac, vid, &ent, &idx, is_valid);
+}
+
+static int bcm_sf2_sw_fdb_prepare(struct dsa_switch *ds, int port,
+				  const struct switchdev_obj_port_fdb *fdb,
+				  struct switchdev_trans *trans)
+{
+	/* We do not need to do anything specific here yet */
+	return 0;
+}
+
+static int bcm_sf2_sw_fdb_add(struct dsa_switch *ds, int port,
+			      const struct switchdev_obj_port_fdb *fdb,
+			      struct switchdev_trans *trans)
+{
+	struct bcm_sf2_priv *priv = ds_to_priv(ds);
+
+	return bcm_sf2_arl_op(priv, 0, port, fdb->addr, fdb->vid, true);
+}
+
+static int bcm_sf2_sw_fdb_del(struct dsa_switch *ds, int port,
+			      const struct switchdev_obj_port_fdb *fdb)
+{
+	struct bcm_sf2_priv *priv = ds_to_priv(ds);
+
+	return bcm_sf2_arl_op(priv, 0, port, fdb->addr, fdb->vid, false);
+}
+
+static int bcm_sf2_arl_search_wait(struct bcm_sf2_priv *priv)
+{
+	unsigned timeout = 1000;
+	u32 reg;
+
+	do {
+		reg = core_readl(priv, CORE_ARLA_SRCH_CTL);
+		if (!(reg & ARLA_SRCH_STDN))
+			return 0;
+
+		if (reg & ARLA_SRCH_VLID)
+			return 0;
+
+		usleep_range(1000, 2000);
+	} while (timeout--);
+
+	return -ETIMEDOUT;
+}
+
+static void bcm_sf2_arl_search_rd(struct bcm_sf2_priv *priv, u8 idx,
+				  struct bcm_sf2_arl_entry *ent)
+{
+	u64 mac_vid;
+	u32 fwd_entry;
+
+	mac_vid = core_readq(priv, CORE_ARLA_SRCH_RSLT_MACVID(idx));
+	fwd_entry = core_readl(priv, CORE_ARLA_SRCH_RSLT(idx));
+	bcm_sf2_arl_to_entry(ent, mac_vid, fwd_entry);
+}
+
+static int bcm_sf2_sw_fdb_copy(struct net_device *dev, int port,
+			       const struct bcm_sf2_arl_entry *ent,
+			       struct switchdev_obj_port_fdb *fdb,
+			       int (*cb)(struct switchdev_obj *obj))
+{
+	if (!ent->is_valid)
+		return 0;
+
+	if (port != ent->port)
+		return 0;
+
+	ether_addr_copy(fdb->addr, ent->mac);
+	fdb->vid = ent->vid;
+	fdb->ndm_state = ent->is_static ? NUD_NOARP : NUD_REACHABLE;
+
+	return cb(&fdb->obj);
+}
+
+static int bcm_sf2_sw_fdb_dump(struct dsa_switch *ds, int port,
+			       struct switchdev_obj_port_fdb *fdb,
+			       int (*cb)(struct switchdev_obj *obj))
+{
+	struct bcm_sf2_priv *priv = ds_to_priv(ds);
+	struct net_device *dev = ds->ports[port];
+	struct bcm_sf2_arl_entry results[2];
+	unsigned int count = 0;
+	int ret;
+
+	/* Start search operation */
+	core_writel(priv, ARLA_SRCH_STDN, CORE_ARLA_SRCH_CTL);
+
+	do {
+		ret = bcm_sf2_arl_search_wait(priv);
+		if (ret)
+			return ret;
+
+		/* Read both entries, then return their values back */
+		bcm_sf2_arl_search_rd(priv, 0, &results[0]);
+		ret = bcm_sf2_sw_fdb_copy(dev, port, &results[0], fdb, cb);
+		if (ret)
+			return ret;
+
+		bcm_sf2_arl_search_rd(priv, 1, &results[1]);
+		ret = bcm_sf2_sw_fdb_copy(dev, port, &results[1], fdb, cb);
+		if (ret)
+			return ret;
+
+		if (!results[0].is_valid && !results[1].is_valid)
+			break;
+
+	} while (count++ < CORE_ARLA_NUM_ENTRIES);
+
+	return 0;
+}
+
 static irqreturn_t bcm_sf2_switch_0_isr(int irq, void *dev_id)
 {
 	struct bcm_sf2_priv *priv = dev_id;
@@ -1076,6 +1308,10 @@ static struct dsa_switch_driver bcm_sf2_switch_driver = {
 	.port_join_bridge	= bcm_sf2_sw_br_join,
 	.port_leave_bridge	= bcm_sf2_sw_br_leave,
 	.port_stp_update	= bcm_sf2_sw_br_set_stp_state,
+	.port_fdb_prepare	= bcm_sf2_sw_fdb_prepare,
+	.port_fdb_add		= bcm_sf2_sw_fdb_add,
+	.port_fdb_del		= bcm_sf2_sw_fdb_del,
+	.port_fdb_dump		= bcm_sf2_sw_fdb_dump,
 };
 
 static int __init bcm_sf2_init(void)

drivers/net/dsa/bcm_sf2.h

@@ -19,6 +19,8 @@
 #include <linux/mutex.h>
 #include <linux/mii.h>
 #include <linux/ethtool.h>
+#include <linux/types.h>
+#include <linux/bitops.h>
 
 #include <net/dsa.h>
 
@@ -50,6 +52,60 @@ struct bcm_sf2_port_status {
 	u32 vlan_ctl_mask;
 };
 
+struct bcm_sf2_arl_entry {
+	u8 port;
+	u8 mac[ETH_ALEN];
+	u16 vid;
+	u8 is_valid:1;
+	u8 is_age:1;
+	u8 is_static:1;
+};
+
+static inline void bcm_sf2_mac_from_u64(u64 src, u8 *dst)
+{
+	unsigned int i;
+
+	for (i = 0; i < ETH_ALEN; i++)
+		dst[ETH_ALEN - 1 - i] = (src >> (8 * i)) & 0xff;
+}
+
+static inline u64 bcm_sf2_mac_to_u64(const u8 *src)
+{
+	unsigned int i;
+	u64 dst = 0;
+
+	for (i = 0; i < ETH_ALEN; i++)
+		dst |= (u64)src[ETH_ALEN - 1 - i] << (8 * i);
+
+	return dst;
+}
+
+static inline void bcm_sf2_arl_to_entry(struct bcm_sf2_arl_entry *ent,
+					u64 mac_vid, u32 fwd_entry)
+{
+	memset(ent, 0, sizeof(*ent));
+	ent->port = fwd_entry & PORTID_MASK;
+	ent->is_valid = !!(fwd_entry & ARL_VALID);
+	ent->is_age = !!(fwd_entry & ARL_AGE);
+	ent->is_static = !!(fwd_entry & ARL_STATIC);
+	bcm_sf2_mac_from_u64(mac_vid, ent->mac);
+	ent->vid = mac_vid >> VID_SHIFT;
+}
+
+static inline void bcm_sf2_arl_from_entry(u64 *mac_vid, u32 *fwd_entry,
+					  const struct bcm_sf2_arl_entry *ent)
+{
+	*mac_vid = bcm_sf2_mac_to_u64(ent->mac);
+	*mac_vid |= (u64)(ent->vid & VID_MASK) << VID_SHIFT;
+	*fwd_entry = ent->port & PORTID_MASK;
+	if (ent->is_valid)
+		*fwd_entry |= ARL_VALID;
+	if (ent->is_static)
+		*fwd_entry |= ARL_STATIC;
+	if (ent->is_age)
+		*fwd_entry |= ARL_AGE;
+}
+
 struct bcm_sf2_priv {
 	/* Base registers, keep those in order with BCM_SF2_REGS_NAME */
 	void __iomem			*core;

drivers/net/dsa/bcm_sf2_regs.h

@@ -231,6 +231,49 @@
 #define CORE_BRCM_HDR_RX_DIS		0x0980
 #define CORE_BRCM_HDR_TX_DIS		0x0988
 
+#define CORE_ARLA_NUM_ENTRIES		1024
+
+#define CORE_ARLA_RWCTL			0x1400
+#define  ARL_RW				(1 << 0)
+#define  IVL_SVL_SELECT			(1 << 6)
+#define  ARL_STRTDN			(1 << 7)
+
+#define CORE_ARLA_MAC			0x1408
+#define CORE_ARLA_VID			0x1420
+#define  ARLA_VIDTAB_INDX_MASK		0x1fff
+
+#define CORE_ARLA_MACVID0		0x1440
+#define  MAC_MASK			0xffffffffff
+#define  VID_SHIFT			48
+#define  VID_MASK			0xfff
+
+#define CORE_ARLA_FWD_ENTRY0		0x1460
+#define  PORTID_MASK			0x1ff
+#define  ARL_CON_SHIFT			9
+#define  ARL_CON_MASK			0x3
+#define  ARL_PRI_SHIFT			11
+#define  ARL_PRI_MASK			0x7
+#define  ARL_AGE			(1 << 14)
+#define  ARL_STATIC			(1 << 15)
+#define  ARL_VALID			(1 << 16)
+
+#define CORE_ARLA_MACVID_ENTRY(x)	(CORE_ARLA_MACVID0 + ((x) * 0x40))
+#define CORE_ARLA_FWD_ENTRY(x)		(CORE_ARLA_FWD_ENTRY0 + ((x) * 0x40))
+
+#define CORE_ARLA_SRCH_CTL		0x1540
+#define  ARLA_SRCH_VLID			(1 << 0)
+#define  IVL_SVL_SELECT			(1 << 6)
+#define  ARLA_SRCH_STDN			(1 << 7)
+
+#define CORE_ARLA_SRCH_ADR		0x1544
+#define  ARLA_SRCH_ADR_VALID		(1 << 15)
+
+#define CORE_ARLA_SRCH_RSLT_0_MACVID	0x1580
+#define CORE_ARLA_SRCH_RSLT_0		0x15a0
+
+#define CORE_ARLA_SRCH_RSLT_MACVID(x)	(CORE_ARLA_SRCH_RSLT_0_MACVID + ((x) * 0x40))
+#define CORE_ARLA_SRCH_RSLT(x)		(CORE_ARLA_SRCH_RSLT_0 + ((x) * 0x40))
+
 #define CORE_MEM_PSM_VDD_CTRL		0x2380
 #define  P_TXQ_PSM_VDD_SHIFT		2
 #define  P_TXQ_PSM_VDD_MASK		0x3