Index: if_ath_tx.c
===================================================================
--- if_ath_tx.c	(revision 242951)
+++ if_ath_tx.c	(working copy)
@@ -623,6 +623,24 @@
 	 */
 	bf_first->bf_last = bf_prev;
 
+	/*
+	 * For non-AR9300 NICs, which require the rate control
+	 * in the final descriptor - let's set that up now.
+	 *
+	 * This is because the filltxdesc() HAL call doesn't
+	 * populate the last segment with rate control information
+	 * if firstSeg is also true.  For non-aggregate frames
+	 * that is fine, as the first frame already has rate control
+	 * info.  But if the last frame in an aggregate has one
+	 * descriptor, both firstseg and lastseg will be true and
+	 * the rate info isn't copied.
+	 *
+	 * This is inefficient on MIPS/ARM platforms that have
+	 * non-cachable memory for TX descriptors, but we'll just
+	 * make do for now.
+	 */
+	ath_hal_setuplasttxdesc(sc->sc_ah, bf_prev->bf_lastds, ds0);
+
 	DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR, "%s: end\n", __func__);
 }