[ Upstream commit a1769bb68a ]
This reverts commit 76d164f582.
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 <zhichen@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
70323cca90