[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20230306124940.865233-2-o.rempel@pengutronix.de>
Date: Mon, 6 Mar 2023 13:49:40 +0100
From: Oleksij Rempel <o.rempel@...gutronix.de>
To: "David S. Miller" <davem@...emloft.net>,
Andrew Lunn <andrew@...n.ch>,
Eric Dumazet <edumazet@...gle.com>,
Florian Fainelli <f.fainelli@...il.com>,
Jakub Kicinski <kuba@...nel.org>,
Paolo Abeni <pabeni@...hat.com>,
Vladimir Oltean <olteanv@...il.com>,
Woojung Huh <woojung.huh@...rochip.com>
Cc: Oleksij Rempel <o.rempel@...gutronix.de>, kernel@...gutronix.de,
linux-kernel@...r.kernel.org, netdev@...r.kernel.org,
UNGLinuxDriver@...rochip.com
Subject: [PATCH net-next v1 2/2] net: dsa: microchip: add ETS Qdisc support for KSZ9477 series
Add ETS Qdisc support for KSZ9477 of switches. Current implementation is
limited to strict priority mode.
Tested on KSZ8563R with following configuration:
tc qdisc replace dev lan2 root handle 1: ets strict 4 \
priomap 3 3 2 2 1 1 0 0
ip link add link lan2 name v1 type vlan id 1 \
egress-qos-map 0:0 1:1 2:2 3:3 4:4 5:5 6:6 7:7
and patched iperf3 version:
https://github.com/esnet/iperf/pull/1476
iperf3 -c 172.17.0.1 -b100M -l1472 -t100 -u -R --sock-prio 2
Signed-off-by: Oleksij Rempel <o.rempel@...gutronix.de>
---
drivers/net/dsa/microchip/ksz_common.c | 178 +++++++++++++++++++++++++
drivers/net/dsa/microchip/ksz_common.h | 12 ++
2 files changed, 190 insertions(+)
diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index ae05fe0b0a81..f32ad39c1d8d 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -3172,12 +3172,190 @@ static int ksz_setup_tc_cbs(struct dsa_switch *ds, int port,
MTI_SHAPING_SRP);
}
+static int ksz_ets_band_to_queue(struct tc_ets_qopt_offload_replace_params *p,
+ int band)
+{
+ /* Compared to queues, bands prioritize packets differently. In strict
+ * priority mode, the lowest priority is assigned to Queue 0 while the
+ * highest priority is given to Band 0.
+ */
+ return p->bands - 1 - band;
+}
+
+static int ksz_queue_set_strict(struct ksz_device *dev, int port, int queue)
+{
+ int ret;
+
+ /* In order to ensure proper prioritization, it is necessary to set the
+ * rate limit for the related queue to zero. Otherwise strict priority
+ * mode will not work.
+ */
+ ret = ksz_pwrite8(dev, port, KSZ9477_REG_PORT_OUT_RATE_0 + queue,
+ KSZ9477_OUT_RATE_NO_LIMIT);
+ if (ret)
+ return ret;
+
+ ret = ksz_pwrite32(dev, port, REG_PORT_MTI_QUEUE_INDEX__4, queue);
+ if (ret)
+ return ret;
+
+ return ksz_setup_tc_mode(dev, port, MTI_SCHEDULE_STRICT_PRIO,
+ MTI_SHAPING_OFF);
+}
+
+static int ksz_queue_set_wrr(struct ksz_device *dev, int port, int queue,
+ int weight)
+{
+ int ret;
+
+ /* In order to ensure proper prioritization, it is necessary to set the
+ * rate limit for the related queue to zero. Otherwise weighted round
+ * robin mode will not work.
+ */
+ ret = ksz_pwrite8(dev, port, KSZ9477_REG_PORT_OUT_RATE_0 + queue,
+ KSZ9477_OUT_RATE_NO_LIMIT);
+ if (ret)
+ return ret;
+
+ ret = ksz_pwrite32(dev, port, REG_PORT_MTI_QUEUE_INDEX__4, queue);
+ if (ret)
+ return ret;
+
+ ret = ksz_setup_tc_mode(dev, port, MTI_SCHEDULE_WRR,
+ MTI_SHAPING_OFF);
+ if (ret)
+ return ret;
+
+ return ksz_pwrite8(dev, port, KSZ9477_PORT_MTI_QUEUE_CTRL_1, weight);
+}
+
+static int ksz_tc_ets_add(struct ksz_device *dev, int port,
+ struct tc_ets_qopt_offload_replace_params *p)
+{
+ int ret, band, tc_prio;
+ u32 queue_map = 0;
+
+ /* Configure queue scheduling mode for all bands. Currently only strict
+ * prio mode is supported.
+ */
+ for (band = 0; band < p->bands; band++) {
+ int queue = ksz_ets_band_to_queue(p, band);
+
+ ret = ksz_queue_set_strict(dev, port, queue);
+ if (ret)
+ return ret;
+ }
+
+ /* Configure the mapping between traffic classes and queues. Note:
+ * priomap variable support 16 traffic classes, but the chip can handle
+ * only 8 classes.
+ */
+ for (tc_prio = 0; tc_prio < ARRAY_SIZE(p->priomap); tc_prio++) {
+ int queue;
+
+ if (tc_prio > KSZ9477_MAX_TC_PRIO)
+ break;
+
+ queue = ksz_ets_band_to_queue(p, p->priomap[tc_prio]);
+ queue_map |= queue << (tc_prio * KSZ9477_PORT_TC_MAP_S);
+ }
+
+ return ksz_pwrite32(dev, port, KSZ9477_PORT_MRI_TC_MAP__4, queue_map);
+}
+
+static int ksz_tc_ets_del(struct ksz_device *dev, int port)
+{
+ int ret, queue;
+
+ /* To restore the default chip configuration, set all queues to use the
+ * WRR scheduler with a weight of 1.
+ */
+ for (queue = 0; queue < dev->info->num_tx_queues; queue++) {
+ ret = ksz_queue_set_wrr(dev, port, queue,
+ KSZ9477_DEFAULT_WRR_WEIGHT);
+ if (ret)
+ return ret;
+ }
+
+ /* Revert the queue mapping for TC-priority to its default setting on
+ * the chip.
+ */
+ return ksz_pwrite32(dev, port, KSZ9477_PORT_MRI_TC_MAP__4,
+ KSZ9477_DEFAULT_TC_MAP);
+}
+
+static int ksz_tc_ets_validate(struct ksz_device *dev, int port,
+ struct tc_ets_qopt_offload_replace_params *p)
+{
+ int band;
+
+ /* Since it is not feasible to share one port among multiple qdisc,
+ * the user must configure all available queues appropriately.
+ */
+ if (p->bands != dev->info->num_tx_queues) {
+ dev_err(dev->dev, "Not supported amount of bands. It should be %d\n",
+ dev->info->num_tx_queues);
+ return -EOPNOTSUPP;
+ }
+
+ for (band = 0; band < p->bands; ++band) {
+ /* The KSZ switches utilize a weighted round robin configuration
+ * where a certain number of packets can be transmitted from a
+ * queue before the next queue is serviced. For more information
+ * on this, refer to section 5.2.8.4 of the KSZ8565R
+ * documentation on the Port Transmit Queue Control 1 Register.
+ * However, the current ETS Qdisc implementation (as of February
+ * 2023) assigns a weight to each queue based on the number of
+ * bytes or extrapolated bandwidth in percentages. Since this
+ * differs from the KSZ switches' method and we don't want to
+ * fake support by converting bytes to packets, we have decided
+ * to return an error instead.
+ */
+ if (p->quanta[band]) {
+ dev_err(dev->dev, "Quanta/weights configuration is not supported.\n");
+ return -EOPNOTSUPP;
+ }
+ }
+
+ return 0;
+}
+
+static int ksz_tc_setup_qdisc_ets(struct dsa_switch *ds, int port,
+ struct tc_ets_qopt_offload *qopt)
+{
+ struct ksz_device *dev = ds->priv;
+ int ret;
+
+ if (qopt->parent != TC_H_ROOT) {
+ dev_err(dev->dev, "Parent should be \"root\"\n");
+ return -EOPNOTSUPP;
+ }
+
+ switch (qopt->command) {
+ case TC_ETS_REPLACE:
+ ret = ksz_tc_ets_validate(dev, port, &qopt->replace_params);
+ if (ret)
+ return ret;
+
+ return ksz_tc_ets_add(dev, port, &qopt->replace_params);
+ case TC_ETS_DESTROY:
+ return ksz_tc_ets_del(dev, port);
+ case TC_ETS_STATS:
+ case TC_ETS_GRAFT:
+ return -EOPNOTSUPP;
+ }
+
+ return -EOPNOTSUPP;
+}
+
static int ksz_setup_tc(struct dsa_switch *ds, int port,
enum tc_setup_type type, void *type_data)
{
switch (type) {
case TC_SETUP_QDISC_CBS:
return ksz_setup_tc_cbs(ds, port, type_data);
+ case TC_SETUP_QDISC_ETS:
+ return ksz_tc_setup_qdisc_ets(ds, port, type_data);
default:
return -EOPNOTSUPP;
}
diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index f53834bbe896..7618a4714e06 100644
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -657,6 +657,15 @@ static inline int is_lan937x(struct ksz_device *dev)
#define KSZ8_LEGAL_PACKET_SIZE 1518
#define KSZ9477_MAX_FRAME_SIZE 9000
+#define KSZ9477_REG_PORT_OUT_RATE_0 0x0420
+#define KSZ9477_OUT_RATE_NO_LIMIT 0
+
+#define KSZ9477_PORT_MRI_TC_MAP__4 0x0808
+#define KSZ9477_DEFAULT_TC_MAP 0x33221100
+
+#define KSZ9477_PORT_TC_MAP_S 4
+#define KSZ9477_MAX_TC_PRIO 7
+
/* CBS related registers */
#define REG_PORT_MTI_QUEUE_INDEX__4 0x0900
@@ -670,6 +679,9 @@ static inline int is_lan937x(struct ksz_device *dev)
#define MTI_SHAPING_SRP 1
#define MTI_SHAPING_TIME_AWARE 2
+#define KSZ9477_PORT_MTI_QUEUE_CTRL_1 0x0915
+#define KSZ9477_DEFAULT_WRR_WEIGHT 1
+
#define REG_PORT_MTI_HI_WATER_MARK 0x0916
#define REG_PORT_MTI_LO_WATER_MARK 0x0918
--
2.30.2
Powered by blists - more mailing lists