From: Tan Tee Min tee.min.tan@linux.intel.com
[ Upstream commit 6d05251d537a4d3835959a8cdd8cbbbdcdc0c904 ]
Qbv users can specify a cycle time that is not equal to the total GCL intervals. Hence, recalculation is necessary here to exclude the time interval that exceeds the cycle time. As those GCL which exceeds the cycle time will be truncated.
According to IEEE Std. 802.1Q-2018 section 8.6.9.2, once the end of the list is reached, it will switch to the END_OF_CYCLE state and leave the gates in the same state until the next cycle is started.
Fixes: ec50a9d437f0 ("igc: Add support for taprio offloading") Signed-off-by: Tan Tee Min tee.min.tan@linux.intel.com Signed-off-by: Muhammad Husaini Zulkifli muhammad.husaini.zulkifli@intel.com Tested-by: Naama Meir naamax.meir@linux.intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/igc/igc_main.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+)
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c index 10690a0cfae1..207b4b5b2e5f 100644 --- a/drivers/net/ethernet/intel/igc/igc_main.c +++ b/drivers/net/ethernet/intel/igc/igc_main.c @@ -6023,6 +6023,21 @@ static int igc_save_qbv_schedule(struct igc_adapter *adapter,
end_time += e->interval;
+ /* If any of the conditions below are true, we need to manually + * control the end time of the cycle. + * 1. Qbv users can specify a cycle time that is not equal + * to the total GCL intervals. Hence, recalculation is + * necessary here to exclude the time interval that + * exceeds the cycle time. + * 2. According to IEEE Std. 802.1Q-2018 section 8.6.9.2, + * once the end of the list is reached, it will switch + * to the END_OF_CYCLE state and leave the gates in the + * same state until the next cycle is started. + */ + if (end_time > adapter->cycle_time || + n + 1 == qopt->num_entries) + end_time = adapter->cycle_time; + for (i = 0; i < adapter->num_tx_queues; i++) { struct igc_ring *ring = adapter->tx_ring[i];