[PATCH 0/2] ath11k/ath12k: implement TX flow control

From: Jose Ignacio Tornos Martinez

Date: Fri Jul 10 2026 - 11:55:03 EST


This series implements custom wake_tx_queue operations for ath11k and
ath12k drivers to prevent hardware ring overflow issues under heavy
traffic.

Without proper flow control, both drivers experience -ENOMEM errors
("failed to transmit frame -12") when the hardware TCL ring fills up.
Additionally, ath12k can hang under sustained high throughput. These
issues are more commonly observed in VMs with PCIe passthrough but
also occur on bare metal systems.

The implementation follows the pattern used in the iwlwifi driver,
checking hardware ring space before dequeuing packets from mac80211.
Per-packet locking serializes ring access while allowing TX completions
to run, preventing deadlocks.

Testing shows stable operation with eliminated -ENOMEM errors, no hangs,
and improved throughput under heavy traffic conditions.

Jose Ignacio Tornos Martinez (2):
wifi: ath11k: implement custom wake_tx_queue with flow control
wifi: ath12k: implement custom wake_tx_queue with flow control

drivers/net/wireless/ath/ath11k/dp.c | 1 +
drivers/net/wireless/ath/ath11k/dp.h | 2 +
drivers/net/wireless/ath/ath11k/mac.c | 49 ++++++++++++++++++++-
drivers/net/wireless/ath/ath12k/dp.c | 1 +
drivers/net/wireless/ath/ath12k/dp.h | 2 +
drivers/net/wireless/ath/ath12k/hal.c | 1 +
drivers/net/wireless/ath/ath12k/wifi7/hw.c | 50 +++++++++++++++++++++-
7 files changed, 104 insertions(+), 2 deletions(-)

--
2.54.0