On Mon, 2023-09-18 at 10:53 +0300, Roger Quadros wrote:

[...]

+static int am65_cpsw_mqprio_verify_shaper(struct am65_cpsw_port *port,
+					  struct tc_mqprio_qopt_offload *mqprio)
+{
+	u64 min_rate_total = 0, max_rate_total = 0;
+	u32 min_rate_msk = 0, max_rate_msk = 0;
+	bool has_min_rate, has_max_rate;
+	int num_tc, i;
+	struct am65_cpsw_mqprio *p_mqprio = &port->qos.mqprio;
+	struct netlink_ext_ack *extack = mqprio->extack;

Please, respect the reverse x-mas tree order.

+
+	if (!(mqprio->flags & TC_MQPRIO_F_SHAPER))
+		return 0;
+
+	if (mqprio->shaper != TC_MQPRIO_SHAPER_BW_RATE)
+		return 0;
+
+	has_min_rate = !!(mqprio->flags & TC_MQPRIO_F_MIN_RATE);
+	has_max_rate = !!(mqprio->flags & TC_MQPRIO_F_MAX_RATE);
+
+	if (!has_min_rate && has_max_rate) {
+		NL_SET_ERR_MSG_MOD(extack, "min_rate is required with max_rate");
+		return -EOPNOTSUPP;
+	}
+
+	if (!has_min_rate)
+		return 0;
+
+	num_tc = mqprio->qopt.num_tc;
+
+	for (i = num_tc - 1; i >= 0; i--) {
+		u32 ch_msk;
+
+		if (mqprio->min_rate[i])
+			min_rate_msk |= BIT(i);
+		min_rate_total +=  mqprio->min_rate[i];
+
+		if (has_max_rate) {
+			if (mqprio->max_rate[i])
+				max_rate_msk |= BIT(i);
+			max_rate_total +=  mqprio->max_rate[i];
+
+			if (!mqprio->min_rate[i] && mqprio->max_rate[i]) {
+				NL_SET_ERR_MSG_FMT_MOD(extack,
+						       "TX tc%d rate max>0 but min=0\n",
+						       i);
+				return -EINVAL;
+			}
+
+			if (mqprio->max_rate[i] &&
+			    mqprio->max_rate[i] < mqprio->min_rate[i]) {
+				NL_SET_ERR_MSG_FMT_MOD(extack,
+						       "TX tc%d rate min(%llu)>max(%llu)\n",
+						       i, mqprio->min_rate[i],
+						       mqprio->max_rate[i]);
+				return -EINVAL;
+			}
+		}
+
+		ch_msk = GENMASK(num_tc - 1, i);
+		if ((min_rate_msk & BIT(i)) && (min_rate_msk ^ ch_msk)) {
+			NL_SET_ERR_MSG_FMT_MOD(extack,
+					       "TX min rate limiting has to be enabled sequentially hi->lo tx_rate_msk%x\n",
+					       min_rate_msk);
+			return -EINVAL;
+		}
+
+		if ((max_rate_msk & BIT(i)) && (max_rate_msk ^ ch_msk)) {
+			NL_SET_ERR_MSG_FMT_MOD(extack,
+					       "TX max rate limiting has to be enabled sequentially hi->lo tx_rate_msk%x\n",
+					       max_rate_msk);
+			return -EINVAL;
+		}
+	}
+
+	min_rate_total *= 8;
+	min_rate_total /= 1000 * 1000;
+	max_rate_total *= 8;
+	max_rate_total /= 1000 * 1000;

For consistency with other code doing the same algebra, you could use a
single statement for both '*' and '/'. You could also add an helper for
that conversion, as there are multiple use-case already.

+
+	if (port->qos.link_speed != SPEED_UNKNOWN) {
+		if (min_rate_total > port->qos.link_speed) {
+			NL_SET_ERR_MSG_FMT_MOD(extack, "TX rate min %llu exceeds link speed %d\n",
+					       min_rate_total, port->qos.link_speed);
+			return -EINVAL;
+		}
+
+		if (max_rate_total > port->qos.link_speed) {
+			NL_SET_ERR_MSG_FMT_MOD(extack, "TX rate max %llu exceeds link speed %d\n",
+					       max_rate_total, port->qos.link_speed);
+			return -EINVAL;
+		}
+	}
+
+	p_mqprio->shaper_en = 1;
+	p_mqprio->max_rate_total = max_t(u64, min_rate_total, max_rate_total);
+
+	return 0;
+}
+
+static void am65_cpsw_reset_tc_mqprio(struct net_device *ndev)
+{
+	struct am65_cpsw_port *port = am65_ndev_to_port(ndev);
+	struct am65_cpsw_mqprio *p_mqprio = &port->qos.mqprio;
+	struct am65_cpsw_common *common = port->common;
+
+	p_mqprio->shaper_en = 0;
+	p_mqprio->max_rate_total = 0;
+
+	am65_cpsw_tx_pn_shaper_reset(port);
+	netdev_reset_tc(ndev);
+	netif_set_real_num_tx_queues(ndev, common->tx_ch_num);
+
+	/* Reset all Queue priorities to 0 */
+	writel(0,
+	       port->port_base + AM65_CPSW_PN_REG_TX_PRI_MAP);

No need to wrap the above statement on multiple lines.

+}
+
+static int am65_cpsw_setup_mqprio(struct net_device *ndev, void *type_data)
+{
+	struct am65_cpsw_port *port = am65_ndev_to_port(ndev);
+	struct am65_cpsw_mqprio *p_mqprio = &port->qos.mqprio;
+	struct tc_mqprio_qopt_offload *mqprio = type_data;
+	struct am65_cpsw_common *common = port->common;
+	struct tc_mqprio_qopt *qopt = &mqprio->qopt;
+	int tc, offset, count, ret, prio;
+	u8 num_tc = qopt->num_tc;
+	u32 tx_prio_map = 0;
+	int i;
+
+	memcpy(&p_mqprio->mqprio_hw, mqprio, sizeof(*mqprio));
+
+	if (!num_tc) {
+		am65_cpsw_reset_tc_mqprio(ndev);
+		return 0;
+	}
+
+	ret = pm_runtime_get_sync(common->dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(common->dev);
+		return ret;
+	}
+
+	ret = am65_cpsw_mqprio_verify_shaper(port, mqprio);
+	if (ret)
+		goto exit_put;
+
+	netdev_set_num_tc(ndev, num_tc);
+
+	/* Multiple Linux priorities can map to a Traffic Class
+	 * A Traffic Class can have multiple contiguous Queues,
+	 * Queues get mapped to Channels (thread_id),
+	 *	if not VLAN tagged, thread_id is used as packet_priority
+	 *	if VLAN tagged. VLAN priority is used as packet_priorit
+	 * packet_priority gets mapped to header_priority in p0_rx_pri_map,
+	 * header_priority gets mapped to switch_priority in pn_tx_pri_map.
+	 * As p0_rx_pri_map is left at defaults (0x76543210), we can
+	 * assume that Queue_n gets mapped to header_priority_n. We can then
+	 * set the switch priority in pn_tx_pri_map.
+	 */
+
+	for (tc = 0; tc < num_tc; tc++) {
+	 /* For simplicity we assign the same priority (TCn) to all queues
+	  * of a Traffic Class.
+	  */

Please align the comment with the relevant code.

[...]

Perhaps 'bool' instead?


Cheers,

Paolo