Hi Ben,
Thanks for your information. The DMA issue is host related. We never
hit this issue with X86 platform. And it was only seen in stress cases
with 50+ STAs(association and disassociation repeatedly). What's the
host platform you are using? And how was the issue reproduced?
Thanks,
Zhi
On 2020-09-09 01:48, Ben Greear wrote:
Hello,
Just FYI: I added this patch to my ath10k-ct driver, and a user
reported it causes
regressions on his particular 9888 system when using ath10k-ct wave-2
firmware:
[ 21.204868] ath10k_pci 0000:00:00.0: qca9888 hw2.0 target
0x01000000 chip_id 0x00000000 sub 0000:0000
[ 21.214437] ath10k_pci 0000:00:00.0: kconfig debug 0 debugfs 1
tracing 0 dfs 1 testmode 0
[ 21.233298] ath10k_pci 0000:00:00.0: firmware ver
10.4b-ct-9888-tH-13-8c5b2baa2 api 5 features
mfp,peer-flow-ctrl,txstatus-noack,wmi-10.x-CT,ratemask-CT,regdump-CT,txrate-CT,flush-all-CT,pingpong-CT,ch-regs-CT,nop-CT,htt-mgt-CT,set-special-CT,no-bmiss-CT,tx-rc-CT,cust-stats-CT,txrate2-CT,beacon-cb-CT,wmi-block-ack-CT,wmi-bcn-rc-CT
crc32 a00b5f36
[ 21.596684] ath10k_pci 0000:00:00.0: board_file api 2 bmi_id 0:20
crc32 5bb32c02[ 23.546156] ath10k_pci 0000:00:00.0: unsupported HTC
service id: 1536
I'll revert this for the 9888 chipset (at least) in my driver,
possibly you need to do similar.
https://github.com/greearb/ath10k-ct/issues/153
Thanks,
Ben
On 1/13/20 8:35 PM, Zhi Chen wrote:
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 <zhichen@xxxxxxxxxxxxxx>
---
v2: restored 10.2 register configuration
v3: modified commit message
v4: resolved conflicts
---
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 21b7a2a..775fd62 100644
--- a/drivers/net/wireless/ath/ath10k/hw.h
+++ b/drivers/net/wireless/ath/ath10k/hw.h
@@ -816,7 +816,7 @@ 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
