ath9k: Fix tx throughput drops for AR9003 chips with AES encryption

commit 4f6760b01bda625e9555e16d8e9ba8126a9c9498 upstream.

While sending aggregated frames in AES, the AR5416 chips
required additional padding b/w subframes. This workaround
is not needed for edma (AR9003 family) chips. With this patch
~4Mbps thoughput improvement was observed in clear environment.

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index 88fa7fdffd05d6ac36c4d45cb2d7416fc0681713..4f2c8dfe4c1bc3a2ffcaca629a67cdef8a3cdbc3 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -662,7 +662,8 @@ static int ath_compute_num_delims(struct ath_softc *sc, struct ath_atx_tid *tid,
         * TODO - this could be improved to be dependent on the rate.
         *      The hardware can keep up at lower rates, but not higher rates
         */
-       if (fi->keyix != ATH9K_TXKEYIX_INVALID)
+       if ((fi->keyix != ATH9K_TXKEYIX_INVALID) &&
+           !(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA))
                ndelim += ATH_AGGR_ENCRYPTDELIM;
 
        /*