From: Zhi Chen Date: Tue, 14 Jan 2020 04:35:21 +0000 (+0800) Subject: Revert "ath10k: fix DMA related firmware crashes on multiple devices" X-Git-Tag: v4.4.235~30 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=08496baa47361f8e4d4710800dbe4ad59d73c086;p=thirdparty%2Fkernel%2Fstable.git Revert "ath10k: fix DMA related firmware crashes on multiple devices" [ Upstream commit a1769bb68a850508a492e3674ab1e5e479b11254 ] This reverts commit 76d164f582150fd0259ec0fcbc485470bcd8033e. PCIe hung issue was observed on multiple platforms. The issue was reproduced when DUT was configured as AP and associated with 50+ STAs. For QCA9984/QCA9888, the DMA_BURST_SIZE register controls the AXI burst size of the RD/WR access to the HOST MEM. 0 - No split , RAW read/write transfer size from MAC is put out on bus as burst length 1 - Split at 256 byte boundary 2,3 - Reserved With PCIe protocol analyzer, we can see DMA Read crossing 4KB boundary when issue happened. It broke PCIe spec and caused PCIe stuck. So revert the default value from 0 to 1. Tested: IPQ8064 + QCA9984 with firmware 10.4-3.10-00047 QCS404 + QCA9984 with firmware 10.4-3.9.0.2--00044 Synaptics AS370 + QCA9888 with firmware 10.4-3.9.0.2--00040 Signed-off-by: Zhi Chen Signed-off-by: Kalle Valo Signed-off-by: Sasha Levin --- diff --git a/drivers/net/wireless/ath/ath10k/hw.h b/drivers/net/wireless/ath/ath10k/hw.h index 713c2bcea1782..8ec5c579d7fa8 100644 --- a/drivers/net/wireless/ath/ath10k/hw.h +++ b/drivers/net/wireless/ath/ath10k/hw.h @@ -429,7 +429,7 @@ enum ath10k_hw_rate_cck { #define TARGET_10_4_TX_DBG_LOG_SIZE 1024 #define TARGET_10_4_NUM_WDS_ENTRIES 32 -#define TARGET_10_4_DMA_BURST_SIZE 0 +#define TARGET_10_4_DMA_BURST_SIZE 1 #define TARGET_10_4_MAC_AGGR_DELIM 0 #define TARGET_10_4_RX_SKIP_DEFRAG_TIMEOUT_DUP_DETECTION_CHECK 1 #define TARGET_10_4_VOW_CONFIG 0