[PATCH v5 net-next 08/10] net: dsa: microchip: add support for port mirror operations

From: Prasanna Vengateshan
Date: Thu Oct 28 2021 - 12:42:29 EST


Added support for port_mirror_add() and port_mirror_del operations

Sniffing is limited to one port & alert the user if any new
sniffing port is selected

Signed-off-by: Prasanna Vengateshan <prasanna.vengateshan@xxxxxxxxxxxxx>
Reviewed-by: Vladimir Oltean <olteanv@xxxxxxxxx>
---
drivers/net/dsa/microchip/lan937x_main.c | 84 ++++++++++++++++++++++++
1 file changed, 84 insertions(+)

diff --git a/drivers/net/dsa/microchip/lan937x_main.c b/drivers/net/dsa/microchip/lan937x_main.c
index 0976a95851c0..ebc50cdc4a2d 100644
--- a/drivers/net/dsa/microchip/lan937x_main.c
+++ b/drivers/net/dsa/microchip/lan937x_main.c
@@ -125,6 +125,88 @@ static void lan937x_port_stp_state_set(struct dsa_switch *ds, int port,
ksz_update_port_member(dev, port);
}

+static int lan937x_port_mirror_add(struct dsa_switch *ds, int port,
+ struct dsa_mall_mirror_tc_entry *mirror,
+ bool ingress)
+{
+ struct ksz_device *dev = ds->priv;
+ int ret, p;
+ u8 data;
+
+ /* Limit to one sniffer port
+ * Check if any of the port is already set for sniffing
+ * If yes, instruct the user to remove the previous entry & exit
+ */
+ for (p = 0; p < dev->port_cnt; p++) {
+ /* Skip the current sniffing port */
+ if (p == mirror->to_local_port)
+ continue;
+
+ ret = lan937x_pread8(dev, p, P_MIRROR_CTRL, &data);
+ if (ret < 0)
+ return ret;
+
+ if (data & PORT_MIRROR_SNIFFER) {
+ dev_err(dev->dev,
+ "Delete existing rules towards %s & try\n",
+ dsa_to_port(ds, p)->name);
+ return -EBUSY;
+ }
+ }
+
+ /* Configure ingress/egress mirroring */
+ if (ingress)
+ ret = lan937x_port_cfg(dev, port, P_MIRROR_CTRL, PORT_MIRROR_RX,
+ true);
+ else
+ ret = lan937x_port_cfg(dev, port, P_MIRROR_CTRL, PORT_MIRROR_TX,
+ true);
+ if (ret < 0)
+ return ret;
+
+ /* Configure sniffer port as other ports do not have
+ * PORT_MIRROR_SNIFFER is set
+ */
+ ret = lan937x_port_cfg(dev, mirror->to_local_port, P_MIRROR_CTRL,
+ PORT_MIRROR_SNIFFER, true);
+ if (ret < 0)
+ return ret;
+
+ return lan937x_cfg(dev, S_MIRROR_CTRL, SW_MIRROR_RX_TX, false);
+}
+
+static void lan937x_port_mirror_del(struct dsa_switch *ds, int port,
+ struct dsa_mall_mirror_tc_entry *mirror)
+{
+ struct ksz_device *dev = ds->priv;
+ bool in_use = false;
+ u8 data;
+ int p;
+
+ /* clear ingress/egress mirroring port */
+ if (mirror->ingress)
+ lan937x_port_cfg(dev, port, P_MIRROR_CTRL, PORT_MIRROR_RX,
+ false);
+ else
+ lan937x_port_cfg(dev, port, P_MIRROR_CTRL, PORT_MIRROR_TX,
+ false);
+
+ /* Check if any of the port is still referring to sniffer port */
+ for (p = 0; p < dev->port_cnt; p++) {
+ lan937x_pread8(dev, p, P_MIRROR_CTRL, &data);
+
+ if ((data & (PORT_MIRROR_RX | PORT_MIRROR_TX))) {
+ in_use = true;
+ break;
+ }
+ }
+
+ /* delete sniffing if there are no other mirroring rule exist */
+ if (!in_use)
+ lan937x_port_cfg(dev, mirror->to_local_port, P_MIRROR_CTRL,
+ PORT_MIRROR_SNIFFER, false);
+}
+
static void lan937x_config_cpu_port(struct dsa_switch *ds)
{
struct ksz_device *dev = ds->priv;
@@ -448,6 +530,8 @@ const struct dsa_switch_ops lan937x_switch_ops = {
.port_bridge_leave = ksz_port_bridge_leave,
.port_stp_state_set = lan937x_port_stp_state_set,
.port_fast_age = ksz_port_fast_age,
+ .port_mirror_add = lan937x_port_mirror_add,
+ .port_mirror_del = lan937x_port_mirror_del,
.port_max_mtu = lan937x_get_max_mtu,
.port_change_mtu = lan937x_change_mtu,
.phylink_validate = lan937x_phylink_validate,
--
2.27.0