6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Xiaolei Wang <xiaolei.wang@xxxxxxxxxxxxx>
[ Upstream commit be27b896529787e23a35ae4befb6337ce73fcca0 ]
The current cbs parameter depends on speed after uplinking,
which is not needed and will report a configuration error
if the port is not initially connected. The UAPI exposed by
tc-cbs requires userspace to recalculate the send slope anyway,
because the formula depends on port_transmit_rate (see man tc-cbs),
which is not an invariant from tc's perspective. Therefore, we
use offload->sendslope and offload->idleslope to derive the
original port_transmit_rate from the CBS formula.
Fixes: 1f705bc61aee ("net: stmmac: Add support for CBS QDISC")
Signed-off-by: Xiaolei Wang <xiaolei.wang@xxxxxxxxxxxxx>
Reviewed-by: Wojciech Drewek <wojciech.drewek@xxxxxxxxx>
Reviewed-by: Vladimir Oltean <olteanv@xxxxxxxxx>
Link: https://lore.kernel.org/r/20240608143524.2065736-1-xiaolei.wang@xxxxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
.../net/ethernet/stmicro/stmmac/stmmac_tc.c | 25 ++++++++-----------
1 file changed, 11 insertions(+), 14 deletions(-)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
index 6ad3e0a119366..2467598f9d92f 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_tc.c
@@ -343,10 +343,11 @@ static int tc_setup_cbs(struct stmmac_priv *priv,
struct tc_cbs_qopt_offload *qopt)
{
u32 tx_queues_count = priv->plat->tx_queues_to_use;
+ s64 port_transmit_rate_kbps;
u32 queue = qopt->queue;
- u32 ptr, speed_div;
u32 mode_to_use;
u64 value;
+ u32 ptr;
int ret;
/* Queue 0 is not AVB capable */
@@ -355,30 +356,26 @@ static int tc_setup_cbs(struct stmmac_priv *priv,
if (!priv->dma_cap.av)
return -EOPNOTSUPP;
+ port_transmit_rate_kbps = qopt->idleslope - qopt->sendslope;
+
/* Port Transmit Rate and Speed Divider */
- switch (priv->speed) {
+ switch (div_s64(port_transmit_rate_kbps, 1000)) {
case SPEED_10000:
- ptr = 32;
- speed_div = 10000000;
- break;
case SPEED_5000:
ptr = 32;
- speed_div = 5000000;
break;
case SPEED_2500:
- ptr = 8;
- speed_div = 2500000;
- break;
case SPEED_1000:
ptr = 8;
- speed_div = 1000000;
break;
case SPEED_100:
ptr = 4;
- speed_div = 100000;
break;
default:
- return -EOPNOTSUPP;
+ netdev_err(priv->dev,
+ "Invalid portTransmitRate %lld (idleSlope - sendSlope)\n",
+ port_transmit_rate_kbps);
+ return -EINVAL;
}
mode_to_use = priv->plat->tx_queues_cfg[queue].mode_to_use;
@@ -398,10 +395,10 @@ static int tc_setup_cbs(struct stmmac_priv *priv,
}
/* Final adjustments for HW */
- value = div_s64(qopt->idleslope * 1024ll * ptr, speed_div);
+ value = div_s64(qopt->idleslope * 1024ll * ptr, port_transmit_rate_kbps);
priv->plat->tx_queues_cfg[queue].idle_slope = value & GENMASK(31, 0);
- value = div_s64(-qopt->sendslope * 1024ll * ptr, speed_div);
+ value = div_s64(-qopt->sendslope * 1024ll * ptr, port_transmit_rate_kbps);
priv->plat->tx_queues_cfg[queue].send_slope = value & GENMASK(31, 0);
value = qopt->hicredit * 1024ll * 8;
--
2.43.0
