ath10k: reduce dma burst size on newer firmware to fix crashes

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

Backport of r46900

git-svn-id: svn://svn.openwrt.org/openwrt/branches/chaos_calmer@46901 3c298f89-4303-0410-b956-a3cf2f4a3e73

package/kernel/mac80211/patches/396-ath10k-fix-DMA-related-firmware-crashes-on-multiple-.patch

@@ -0,0 +1,24 @@
+From: Felix Fietkau <nbd@openwrt.org>
+Date: Sun, 13 Sep 2015 22:26:10 +0200
+Subject: [PATCH] ath10k: fix DMA related firmware crashes on multiple devices
+
+Some platforms really don't like DMA bursts of 256 bytes, and this
+causes the firmware to crash when sending beacons.
+Also, changing this based on the firmware version does not seem to make
+much sense, so use 128 bytes for all versions.
+
+Cc: stable@vger.kernel.org
+Signed-off-by: Felix Fietkau <nbd@openwrt.org>
+---
+
+--- a/drivers/net/wireless/ath/ath10k/hw.h
++++ b/drivers/net/wireless/ath/ath10k/hw.h
+@@ -253,7 +253,7 @@ struct ath10k_pktlog_hdr {
+ #define TARGET_10X_MAX_FRAG_ENTRIES		0
+ 
+ /* 10.2 parameters */
+-#define TARGET_10_2_DMA_BURST_SIZE		1
++#define TARGET_10_2_DMA_BURST_SIZE		0
+ 
+ /* Target specific defines for WMI-TLV firmware */
+ #define TARGET_TLV_NUM_VDEVS			3