This commit allows the setting of the MAC table aging in the R-Car S4
Rswitch using the SWITCHDEV_ATTR_ID_BRIDGE_AGEING_TIME attribute.

Signed-off-by: Michael Dege <michael.dege@renesas.com>
---
 drivers/net/ethernet/renesas/rswitch.h    |  1 +
 drivers/net/ethernet/renesas/rswitch_l2.c | 26 ++++++++++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/drivers/net/ethernet/renesas/rswitch.h b/drivers/net/ethernet/renesas/rswitch.h
index 45a9d02c5b5d3e7b62554bd56c6c0cb9231f684c..11ff1102668b081e395664ea73e19e0ecef74e24 100644
--- a/drivers/net/ethernet/renesas/rswitch.h
+++ b/drivers/net/ethernet/renesas/rswitch.h
@@ -849,6 +849,7 @@ enum rswitch_gwca_mode {
 #define FWMACAGC_MACDESOG	BIT(29)
 
 #define RSW_AGEING_TIME		300
+#define RSW_MAX_AGEING_TIME	65535
 
 /* TOP */
 #define TPEMIMC7(queue)		(TPEMIMC70 + (queue) * 4)
diff --git a/drivers/net/ethernet/renesas/rswitch_l2.c b/drivers/net/ethernet/renesas/rswitch_l2.c
index 242beb1f15c089585f5fe5019f626df8824b971a..c8a8a60a20e70f7ce421280ed35c0c4afe1ed039 100644
--- a/drivers/net/ethernet/renesas/rswitch_l2.c
+++ b/drivers/net/ethernet/renesas/rswitch_l2.c
@@ -196,6 +196,30 @@ static int rswitch_netdevice_event(struct notifier_block *nb,
 	return NOTIFY_OK;
 }
 
+static int rswitch_update_ageing_time(struct net_device *ndev, clock_t time)
+{
+	struct rswitch_device *rdev = netdev_priv(ndev);
+	u32 reg_val, time_val;
+
+	if (!is_rdev(ndev))
+		return -ENODEV;
+
+	/* Although brctl accepts the ageing time parameter in seconds, the value
+	 * passed to the driver is multiplied by 100. We need it in seconds.
+	 */
+	time_val = (u32)time / 100;
+
+	if (time_val > RSW_MAX_AGEING_TIME)
+		return -EINVAL;
+
+	rdev = netdev_priv(ndev);
+	reg_val = FIELD_PREP(FWMACAGC_MACAGT, time_val);
+	reg_val |= FWMACAGC_MACAGE | FWMACAGC_MACAGSL;
+	iowrite32(reg_val, rdev->priv->addr + FWMACAGC);
+
+	return 0;
+}
+
 static int rswitch_port_attr_set(struct net_device *ndev, const void *ctx,
 				 const struct switchdev_attr *attr,
 				 struct netlink_ext_ack *extack)
@@ -203,6 +227,8 @@ static int rswitch_port_attr_set(struct net_device *ndev, const void *ctx,
 	switch (attr->id) {
 	case SWITCHDEV_ATTR_ID_PORT_STP_STATE:
 		return rswitch_port_update_stp_state(ndev, attr->u.stp_state);
+	case SWITCHDEV_ATTR_ID_BRIDGE_AGEING_TIME:
+		return rswitch_update_ageing_time(ndev, attr->u.ageing_time);
 	default:
 		return -EOPNOTSUPP;
 	}

-- 
2.49.0

Hi Michael,

On Fri, 4 Jul 2025 at 07:52, Michael Dege <michael.dege@renesas.com> wrote:
> This commit allows the setting of the MAC table aging in the R-Car S4
> Rswitch using the SWITCHDEV_ATTR_ID_BRIDGE_AGEING_TIME attribute.
>
> Signed-off-by: Michael Dege <michael.dege@renesas.com>

Thanks for your patch!

> --- a/drivers/net/ethernet/renesas/rswitch.h
> +++ b/drivers/net/ethernet/renesas/rswitch.h
> @@ -849,6 +849,7 @@ enum rswitch_gwca_mode {
>  #define FWMACAGC_MACDESOG      BIT(29)
>
>  #define RSW_AGEING_TIME                300
> +#define RSW_MAX_AGEING_TIME    65535

This is not needed (see below).

>
>  /* TOP */
>  #define TPEMIMC7(queue)                (TPEMIMC70 + (queue) * 4)
> diff --git a/drivers/net/ethernet/renesas/rswitch_l2.c b/drivers/net/ethernet/renesas/rswitch_l2.c
> index 242beb1f15c089585f5fe5019f626df8824b971a..c8a8a60a20e70f7ce421280ed35c0c4afe1ed039 100644
> --- a/drivers/net/ethernet/renesas/rswitch_l2.c
> +++ b/drivers/net/ethernet/renesas/rswitch_l2.c
> @@ -196,6 +196,30 @@ static int rswitch_netdevice_event(struct notifier_block *nb,
>         return NOTIFY_OK;
>  }
>
> +static int rswitch_update_ageing_time(struct net_device *ndev, clock_t time)
> +{
> +       struct rswitch_device *rdev = netdev_priv(ndev);
> +       u32 reg_val, time_val;
> +
> +       if (!is_rdev(ndev))
> +               return -ENODEV;
> +
> +       /* Although brctl accepts the ageing time parameter in seconds, the value
> +        * passed to the driver is multiplied by 100. We need it in seconds.
> +        */
> +       time_val = (u32)time / 100;

switchdev_attr.u.ageing_time is clock_t, which is long, so no cast is
needed before doing the division.  Actually the cast may truncate very
large values on 64-bit.
However, dropping the cast means time_val should be changed to clock_t.

> +
> +       if (time_val > RSW_MAX_AGEING_TIME)

if (!FIELD_FIT(FWMACAGC_MACAGT, time_val))

> +               return -EINVAL;
> +
> +       rdev = netdev_priv(ndev);
> +       reg_val = FIELD_PREP(FWMACAGC_MACAGT, time_val);
> +       reg_val |= FWMACAGC_MACAGE | FWMACAGC_MACAGSL;
> +       iowrite32(reg_val, rdev->priv->addr + FWMACAGC);
> +
> +       return 0;
> +}
> +
>  static int rswitch_port_attr_set(struct net_device *ndev, const void *ctx,
>                                  const struct switchdev_attr *attr,
>                                  struct netlink_ext_ack *extack)

Gr{oetje,eeting}s,

                        Geert


--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds