[PATCH net-next v4 2/2] net: dsa: microchip: add property to select internal RMII reference clock

Ante Knezic
2023-10-20T14:26:58Z

Microchip KSZ8863/KSZ8873 have the ability to select between internal
and external RMII reference clock. By default, reference clock
needs to be provided via REFCLKI_3 pin. If required, device can be
setup to provide RMII clock internally so that REFCLKI_3 pin can be
left unconnected.
Add a new "microchip,rmii-clk-internal" property which will set
RMII clock reference to internal. If property is not set, reference
clock needs to be provided externally.

While at it, move the ksz8795_cpu_interface_select() to
ksz8_config_cpu_port() to get a cleaner call path for cpu port.

Signed-off-by: Ante Knezic <ante.knezic@helmholz.de>
---
drivers/net/dsa/microchip/ksz8795.c | 28 ++++++++++++++++++++++------
drivers/net/dsa/microchip/ksz8795_reg.h | 3 +++
2 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz8795.c b/drivers/net/dsa/microchip/ksz8795.c
index 4bf4d67557dc..b0a305b7c37e 100644
--- a/drivers/net/dsa/microchip/ksz8795.c
+++ b/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 +1394,28 @@ 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)
+{
+ bool rmii_clk_internal;
+
+ if (!ksz_is_ksz88x3(dev))
+ return;
+
+ rmii_clk_internal = of_property_read_bool(dev->dev->of_node,
+ "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 +1432,9 @@ 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);
}
diff --git a/drivers/net/dsa/microchip/ksz8795_reg.h b/drivers/net/dsa/microchip/ksz8795_reg.h
index 3c9dae53e4d8..beca974e0171 100644
--- a/drivers/net/dsa/microchip/ksz8795_reg.h
+++ b/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)
--
2.11.0