[PATCH v3 net-next 10/13] net: mscc: ocelot: add support for mqprio offload

From: Vladimir Oltean
Date: Mon Feb 20 2023 - 07:25:57 EST


This doesn't apply anything to hardware and in general doesn't do
anything that the software variant doesn't do, except for checking that
there isn't more than 1 TXQ per TC (TXQs for a DSA switch are a dubious
concept anyway). The reason we add this is to be able to parse one more
field added to struct tc_mqprio_qopt_offload, namely preemptible_tcs.

Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
Reviewed-by: Ferenc Fejes <fejes@xxxxxxxxxxx>
---
v2->v3: use NL_SET_ERR_MSG_MOD() instead of netdev_err()
v1->v2: none

drivers/net/dsa/ocelot/felix_vsc9959.c | 9 +++++
drivers/net/ethernet/mscc/ocelot.c | 50 ++++++++++++++++++++++++++
include/soc/mscc/ocelot.h | 4 +++
3 files changed, 63 insertions(+)

diff --git a/drivers/net/dsa/ocelot/felix_vsc9959.c b/drivers/net/dsa/ocelot/felix_vsc9959.c
index 354aa3dbfde7..3df71444dde1 100644
--- a/drivers/net/dsa/ocelot/felix_vsc9959.c
+++ b/drivers/net/dsa/ocelot/felix_vsc9959.c
@@ -1612,6 +1612,13 @@ static int vsc9959_qos_port_cbs_set(struct dsa_switch *ds, int port,
static int vsc9959_qos_query_caps(struct tc_query_caps_base *base)
{
switch (base->type) {
+ case TC_SETUP_QDISC_MQPRIO: {
+ struct tc_mqprio_caps *caps = base->caps;
+
+ caps->validate_queue_counts = true;
+
+ return 0;
+ }
case TC_SETUP_QDISC_TAPRIO: {
struct tc_taprio_caps *caps = base->caps;

@@ -1635,6 +1642,8 @@ static int vsc9959_port_setup_tc(struct dsa_switch *ds, int port,
return vsc9959_qos_query_caps(type_data);
case TC_SETUP_QDISC_TAPRIO:
return vsc9959_qos_port_tas_set(ocelot, port, type_data);
+ case TC_SETUP_QDISC_MQPRIO:
+ return ocelot_port_mqprio(ocelot, port, type_data);
case TC_SETUP_QDISC_CBS:
return vsc9959_qos_port_cbs_set(ds, port, type_data);
default:
diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c
index 08acb7b89086..8227d2027c94 100644
--- a/drivers/net/ethernet/mscc/ocelot.c
+++ b/drivers/net/ethernet/mscc/ocelot.c
@@ -7,6 +7,7 @@
#include <linux/dsa/ocelot.h>
#include <linux/if_bridge.h>
#include <linux/iopoll.h>
+#include <net/pkt_sched.h>
#include <soc/mscc/ocelot_vcap.h>
#include "ocelot.h"
#include "ocelot_vcap.h"
@@ -2602,6 +2603,55 @@ void ocelot_port_mirror_del(struct ocelot *ocelot, int from, bool ingress)
}
EXPORT_SYMBOL_GPL(ocelot_port_mirror_del);

+static void ocelot_port_reset_mqprio(struct ocelot *ocelot, int port)
+{
+ struct net_device *dev = ocelot->ops->port_to_netdev(ocelot, port);
+
+ netdev_reset_tc(dev);
+}
+
+int ocelot_port_mqprio(struct ocelot *ocelot, int port,
+ struct tc_mqprio_qopt_offload *mqprio)
+{
+ struct net_device *dev = ocelot->ops->port_to_netdev(ocelot, port);
+ struct netlink_ext_ack *extack = mqprio->extack;
+ struct tc_mqprio_qopt *qopt = &mqprio->qopt;
+ int num_tc = qopt->num_tc;
+ int tc, err;
+
+ if (!num_tc) {
+ ocelot_port_reset_mqprio(ocelot, port);
+ return 0;
+ }
+
+ err = netdev_set_num_tc(dev, num_tc);
+ if (err)
+ return err;
+
+ for (tc = 0; tc < num_tc; tc++) {
+ if (qopt->count[tc] != 1) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "Only one TXQ per TC supported");
+ return -EINVAL;
+ }
+
+ err = netdev_set_tc_queue(dev, tc, 1, qopt->offset[tc]);
+ if (err)
+ goto err_reset_tc;
+ }
+
+ err = netif_set_real_num_tx_queues(dev, num_tc);
+ if (err)
+ goto err_reset_tc;
+
+ return 0;
+
+err_reset_tc:
+ ocelot_port_reset_mqprio(ocelot, port);
+ return err;
+}
+EXPORT_SYMBOL_GPL(ocelot_port_mqprio);
+
void ocelot_init_port(struct ocelot *ocelot, int port)
{
struct ocelot_port *ocelot_port = ocelot->ports[port];
diff --git a/include/soc/mscc/ocelot.h b/include/soc/mscc/ocelot.h
index 2080879e4134..27ff770a6c53 100644
--- a/include/soc/mscc/ocelot.h
+++ b/include/soc/mscc/ocelot.h
@@ -11,6 +11,8 @@
#include <linux/regmap.h>
#include <net/dsa.h>

+struct tc_mqprio_qopt_offload;
+
/* Port Group IDs (PGID) are masks of destination ports.
*
* For L2 forwarding, the switch performs 3 lookups in the PGID table for each
@@ -1145,6 +1147,8 @@ int ocelot_port_set_mm(struct ocelot *ocelot, int port,
struct netlink_ext_ack *extack);
int ocelot_port_get_mm(struct ocelot *ocelot, int port,
struct ethtool_mm_state *state);
+int ocelot_port_mqprio(struct ocelot *ocelot, int port,
+ struct tc_mqprio_qopt_offload *mqprio);

#if IS_ENABLED(CONFIG_BRIDGE_MRP)
int ocelot_mrp_add(struct ocelot *ocelot, int port,
--
2.34.1