Merge branch 'dsa-microchip-rmii-reference'

Ante Knezic says:

====================
net: dsa: microchip: enable setting rmii reference

KSZ88X3 devices can select between internal and external RMII reference clock.
This patch series introduces new device tree property for setting reference
clock to internal.

---
V5:
  - move rmii-clk-internal to be a port device tree property.
V4:
  - remove rmii_clk_internal from ksz_device, as its not needed any more
  - move rmii clk config as well as ksz8795_cpu_interface_select to
    ksz8_config_cpu_port
V3:
  - move ksz_cfg from global switch config to port config as suggested by Vladimir
    Oltean
  - reverse patch order as suggested by Vladimir Oltean
  - adapt dt schema as suggested by Conor Dooley
V2:
  - don't rely on default register settings - enforce set/clear property as
    suggested by Andrew Lunn
  - enforce dt schema as suggested by Conor Dooley
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/dsa/microchip,ksz.yaml

@@ -11,7 +11,6 @@ maintainers:
   - Woojung Huh <Woojung.Huh@microchip.com>
 
 allOf:
-  - $ref: dsa.yaml#/$defs/ethernet-ports
   - $ref: /schemas/spi/spi-peripheral-props.yaml#
 
 properties:
@@ -78,6 +77,39 @@ required:
   - compatible
   - reg
 
+if:
+  not:
+    properties:
+      compatible:
+        enum:
+          - microchip,ksz8863
+          - microchip,ksz8873
+then:
+  $ref: dsa.yaml#/$defs/ethernet-ports
+else:
+  patternProperties:
+    "^(ethernet-)?ports$":
+      patternProperties:
+        "^(ethernet-)?port@[0-2]$":
+          $ref: dsa-port.yaml#
+          unevaluatedProperties: false
+          properties:
+            microchip,rmii-clk-internal:
+              $ref: /schemas/types.yaml#/definitions/flag
+              description:
+                When ksz88x3 is acting as clock provier (via REFCLKO) it
+                can select between internal and external RMII reference
+                clock. Internal reference clock means that the clock for
+                the RMII of ksz88x3 is provided by the ksz88x3 internally
+                and the REFCLKI pin is unconnected. For the external
+                reference clock, the clock needs to be fed back to ksz88x3
+                via REFCLKI.
+                If microchip,rmii-clk-internal is set, ksz88x3 will provide
+                rmii reference clock internally, otherwise reference clock
+                should be provided externally.
+          dependencies:
+            microchip,rmii-clk-internal: [ethernet]
+
 unevaluatedProperties: false
 
 examples:

drivers/net/dsa/microchip/ksz8795.c

@@ -1358,6 +1358,9 @@ static void ksz8795_cpu_interface_select(struct ksz_device *dev, int port)
 {
 	struct ksz_port *p = &dev->ports[port];
 
+	if (!ksz_is_ksz87xx(dev))
+		return;
+
 	if (!p->interface && dev->compat_interface) {
 		dev_warn(dev->dev,
 			 "Using legacy switch \"phy-mode\" property, because it is missing on port %d node. "
@@ -1391,18 +1394,29 @@ void ksz8_port_setup(struct ksz_device *dev, int port, bool cpu_port)
 	/* enable 802.1p priority */
 	ksz_port_cfg(dev, port, P_PRIO_CTRL, PORT_802_1P_ENABLE, true);
 
-	if (cpu_port) {
-		if (!ksz_is_ksz88x3(dev))
-			ksz8795_cpu_interface_select(dev, port);
-
+	if (cpu_port)
 		member = dsa_user_ports(ds);
-	} else {
+	else
 		member = BIT(dsa_upstream_port(ds, port));
-	}
 
 	ksz8_cfg_port_member(dev, port, member);
 }
 
+static void ksz88x3_config_rmii_clk(struct ksz_device *dev)
+{
+	struct dsa_port *cpu_dp = dsa_to_port(dev->ds, dev->cpu_port);
+	bool rmii_clk_internal;
+
+	if (!ksz_is_ksz88x3(dev))
+		return;
+
+	rmii_clk_internal = of_property_read_bool(cpu_dp->dn,
+						  "microchip,rmii-clk-internal");
+
+	ksz_cfg(dev, KSZ88X3_REG_FVID_AND_HOST_MODE,
+		KSZ88X3_PORT3_RMII_CLK_INTERNAL, rmii_clk_internal);
+}
+
 void ksz8_config_cpu_port(struct dsa_switch *ds)
 {
 	struct ksz_device *dev = ds->priv;
@@ -1419,6 +1433,9 @@ void ksz8_config_cpu_port(struct dsa_switch *ds)
 
 	ksz8_port_setup(dev, dev->cpu_port, true);
 
+	ksz8795_cpu_interface_select(dev, dev->cpu_port);
+	ksz88x3_config_rmii_clk(dev);
+
 	for (i = 0; i < dev->phy_port_cnt; i++) {
 		ksz_port_stp_state_set(ds, i, BR_STATE_DISABLED);
 	}

drivers/net/dsa/microchip/ksz8795_reg.h

@@ -22,6 +22,9 @@
 #define KSZ8863_GLOBAL_SOFTWARE_RESET	BIT(4)
 #define KSZ8863_PCS_RESET		BIT(0)
 
+#define KSZ88X3_REG_FVID_AND_HOST_MODE  0xC6
+#define KSZ88X3_PORT3_RMII_CLK_INTERNAL BIT(3)
+
 #define REG_SW_CTRL_0			0x02
 
 #define SW_NEW_BACKOFF			BIT(7)