Currently for WCN3990, the host driver can send two wmi commands at once, now it is limiting to one because if HOST wants to initiate 2 DMA transfers, it is possible when copy complete interrupt for first DMA reaches HOST, CE has already updated SRRI for both DMA transfers and is in the middle of 2nd DMA. HOST uses SRRI to interpret how many DMA’s have been completed and tries to unmap/free both the DMA entries, but CE is still in the middle of 2nd DMA which can cause SMMU issues or corruption. We are seeing a corner case smmu fault issue where copy engine is still accessing the memory though host unmaps it hence as work around we are delaying the unmapping the memory and tx credit to one. Youghandhar Chintala (2): ath10k: Set tx credit to one for wcn3990 snoc based devices ath10k: Delay the unmapping of the buffer drivers/net/wireless/ath/ath10k/core.c | 30 ++++++++++++++++++++++++++ drivers/net/wireless/ath/ath10k/htc.c | 18 +++++++++++++--- drivers/net/wireless/ath/ath10k/htc.h | 1 + drivers/net/wireless/ath/ath10k/hw.h | 6 ++++++ 4 files changed, 52 insertions(+), 3 deletions(-) -- 2.29.0