net: dsa: mv88e6xxx: add field to specify internal phys layout

mv88e6xxx currently assumes that switch equipped with internal phys have
those phys mapped contiguously starting from port 0 (see
mv88e6xxx_phy_is_internal). However, some switches have internal PHYs but
NOT starting from port 0. For example 88e6393X, 88E6193X and 88E6191X have
integrated PHYs available on ports 1 to 8
To properly support this offset, add a new field to allow specifying an
internal PHYs layout. If field is not set, default layout is assumed (start
at port 0)
Signed-off-by: Alexis Lothoré <alexis.lothore@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/dsa/mv88e6xxx/chip.c

@@ -465,7 +465,9 @@ static int mv88e6xxx_port_setup_mac(struct mv88e6xxx_chip *chip, int port,
 
 static int mv88e6xxx_phy_is_internal(struct mv88e6xxx_chip *chip, int port)
 {
-	return port < chip->info->num_internal_phys;
+	return port >= chip->info->internal_phys_offset &&
+		port < chip->info->num_internal_phys +
+			chip->info->internal_phys_offset;
 }
 
 static int mv88e6xxx_port_ppu_updates(struct mv88e6xxx_chip *chip, int port)

drivers/net/dsa/mv88e6xxx/chip.h

@@ -167,6 +167,11 @@ struct mv88e6xxx_info {
 
 	/* Supports PTP */
 	bool ptp_support;
+
+	/* Internal PHY start index. 0 means that internal PHYs range starts at
+	 * port 0, 1 means internal PHYs range starts at port 1, etc
+	 */
+	unsigned int internal_phys_offset;
 };
 
 struct mv88e6xxx_atu_entry {

drivers/net/dsa/mv88e6xxx/global2.c

@@ -1196,9 +1196,12 @@ int mv88e6xxx_g2_irq_setup(struct mv88e6xxx_chip *chip)
 int mv88e6xxx_g2_irq_mdio_setup(struct mv88e6xxx_chip *chip,
 				struct mii_bus *bus)
 {
+	int phy_start = chip->info->internal_phys_offset;
+	int phy_end = chip->info->internal_phys_offset +
+		      chip->info->num_internal_phys;
 	int phy, irq;
 
-	for (phy = 0; phy < chip->info->num_internal_phys; phy++) {
+	for (phy = phy_start; phy < phy_end; phy++) {
 		irq = irq_find_mapping(chip->g2_irq.domain, phy);
 		if (irq < 0)
 			return irq;