net: dsa: mv88e6xxx: use mv88e6185_g1_vtu_getnext() for the 6250

mv88e6250_g1_vtu_getnext is almost identical to
mv88e6185_g1_vtu_getnext, except for the 6250 only having 64 databases
instead of 256. We can reduce code duplication by simply masking off
the extra two garbage bits when assembling the fid from VTU op [3:0]
and [11:8].

Reviewed-by: Tobias Waldekranz <tobias@waldekranz.com>
Tested-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/dsa/mv88e6xxx/chip.c

@@ -4049,7 +4049,7 @@ static const struct mv88e6xxx_ops mv88e6250_ops = {
 	.mgmt_rsvd2cpu = mv88e6352_g2_mgmt_rsvd2cpu,
 	.pot_clear = mv88e6xxx_g2_pot_clear,
 	.reset = mv88e6250_g1_reset,
-	.vtu_getnext = mv88e6250_g1_vtu_getnext,
+	.vtu_getnext = mv88e6185_g1_vtu_getnext,
 	.vtu_loadpurge = mv88e6250_g1_vtu_loadpurge,
 	.avb_ops = &mv88e6352_avb_ops,
 	.ptp_ops = &mv88e6250_ptp_ops,

drivers/net/dsa/mv88e6xxx/global1.h

@@ -336,8 +336,6 @@ int mv88e6185_g1_vtu_getnext(struct mv88e6xxx_chip *chip,
 			     struct mv88e6xxx_vtu_entry *entry);
 int mv88e6185_g1_vtu_loadpurge(struct mv88e6xxx_chip *chip,
 			       struct mv88e6xxx_vtu_entry *entry);
-int mv88e6250_g1_vtu_getnext(struct mv88e6xxx_chip *chip,
-			     struct mv88e6xxx_vtu_entry *entry);
 int mv88e6250_g1_vtu_loadpurge(struct mv88e6xxx_chip *chip,
 			       struct mv88e6xxx_vtu_entry *entry);
 int mv88e6352_g1_vtu_getnext(struct mv88e6xxx_chip *chip,

drivers/net/dsa/mv88e6xxx/global1_vtu.c

@@ -336,39 +336,6 @@ int mv88e6xxx_g1_vtu_getnext(struct mv88e6xxx_chip *chip,
 	return mv88e6xxx_g1_vtu_vid_read(chip, entry);
 }
 
-int mv88e6250_g1_vtu_getnext(struct mv88e6xxx_chip *chip,
-			     struct mv88e6xxx_vtu_entry *entry)
-{
-	u16 val;
-	int err;
-
-	err = mv88e6xxx_g1_vtu_getnext(chip, entry);
-	if (err)
-		return err;
-
-	if (entry->valid) {
-		err = mv88e6185_g1_vtu_data_read(chip, entry);
-		if (err)
-			return err;
-
-		err = mv88e6185_g1_stu_data_read(chip, entry);
-		if (err)
-			return err;
-
-		/* VTU DBNum[3:0] are located in VTU Operation 3:0
-		 * VTU DBNum[5:4] are located in VTU Operation 9:8
-		 */
-		err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_VTU_OP, &val);
-		if (err)
-			return err;
-
-		entry->fid = val & 0x000f;
-		entry->fid |= (val & 0x0300) >> 4;
-	}
-
-	return 0;
-}
-
 int mv88e6185_g1_vtu_getnext(struct mv88e6xxx_chip *chip,
 			     struct mv88e6xxx_vtu_entry *entry)
 {
@@ -389,14 +356,15 @@ int mv88e6185_g1_vtu_getnext(struct mv88e6xxx_chip *chip,
 			return err;
 
 		/* VTU DBNum[3:0] are located in VTU Operation 3:0
-		 * VTU DBNum[7:4] are located in VTU Operation 11:8
+		 * VTU DBNum[7:4] ([5:4] for 6250) are located in VTU Operation 11:8 (9:8)
 		 */
 		err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_VTU_OP, &val);
 		if (err)
 			return err;
 
 		entry->fid = val & 0x000f;
 		entry->fid |= (val & 0x0f00) >> 4;
+		entry->fid &= mv88e6xxx_num_databases(chip) - 1;
 	}
 
 	return 0;