[PATCH RFC,v2] Revert "ath10k: fix DMA related firmware crashes on multiple devices"

[PATCH RFC,v2] Revert "ath10k: fix DMA related firmware crashes on multiple devices"

[Zhi Chen]

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.

With PCIe protocol analyzer, we can see DMA Read crossing 4KB boundary when
issue happened. It broke PCIe spec and caused PCIe stuck.

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 <zhichen@codeaurora.org>
---
v2: revert 10.4 only because old chips have different AXI RD/WR CFG
---
 drivers/net/wireless/ath/ath10k/hw.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath10k/hw.h b/drivers/net/wireless/ath/ath10k/hw.h
index 35a3623..59a9a58 100644
--- a/drivers/net/wireless/ath/ath10k/hw.h
+++ b/drivers/net/wireless/ath/ath10k/hw.h
@@ -813,7 +813,7 @@ ath10k_is_rssi_enable(struct ath10k_hw_params *hw,
 
 #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
-- 
2.7.4

Re: [PATCH RFC, v2] Revert "ath10k: fix DMA related firmware crashes on multiple devices"

[Kalle Valo]

Zhi Chen <zhichen@codeaurora.org> writes:

> 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.
>
> With PCIe protocol analyzer, we can see DMA Read crossing 4KB boundary when
> issue happened. It broke PCIe spec and caused PCIe stuck.
>
> 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 <zhichen@codeaurora.org>
> ---

All comments under --- line is not added to the git repository.

> v2: revert 10.4 only because old chips have different AXI RD/WR CFG

So you should also mention this in the commit log so it gets properly
archived.

And in the next version please remove RFC, as it seems we are reaching a
consensus that is the right approach. Or are there any comments?

-- 
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