• Zhi Chen's avatar
    Revert "ath10k: fix DMA related firmware crashes on multiple devices" · 01bb0556
    Zhi Chen authored
    [ Upstream commit a1769bb6 ]
    
    This reverts commit 76d164f5.
    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: default avatarZhi Chen <zhichen@codeaurora.org>
    Signed-off-by: default avatarKalle Valo <kvalo@codeaurora.org>
    Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
    01bb0556
hw.h 27.6 KB