PCIE IOMMU fault with Wifi Module WMX7205

[kunyang_fan]

Hi all,

We encounter the IOMMU fault with the WIFI module WMX7205, whose wifi chip is QCA WCN6856.
Our code base is L4T 32.7.1. It seems SMMU problem. The kernel log is in the file
kernel_msg_tx2.txt (74.9 KB) .
We find the below error messages:

[  641.454603] arm-smmu 12000000.iommu: Unhandled context fault: iova=0x7f66c000, fsynr=0x1, cb=20, sid=17(0x11 - AFI), pgd=0, pud=0, pmd=0, pte=0
[  641.454676] mc-err: vpr base=0:c6000000, size=20, ctrl=3, override:(e01a8341, 1dc10c1, 2a800000, 2)
[  641.454689] mc-err: (255) csw_afiw: MC request violates VPR requirements
[  641.454699] mc-err:   status = 0x00337031; addr = 0x3ffffffc0
[  641.454708] mc-err:   secure: yes, access-type: write
[  641.454727] mc-err: unknown mcerr fault, int_status=0x00000000, ch_int_status=0x00000000, hubc_int_status=0x00000000
[  641.454743] mc-err: unknown mcerr fault, int_status=0x00000000, ch_int_status=0x00000000, hubc_int_status=0x00000000
[  641.454757] mc-err: unknown mcerr fault, int_status=0x00000000, ch_int_status=0x00000000, hubc_int_status=0x00000000
[  641.454770] mc-err: Too many MC errors; throttling prints
[  641.467743] arm-smmu 12000000.iommu: Unhandled context fault: iova=0x7f66c000, fsynr=0x1, cb=20, sid=17(0x11 - AFI), pgd=0, pud=0, pmd=0, pte=0

Thanks,

[kayccc]

We don’t have experience with this WIFI module WMX7205 (wifi chip is QCA WCN6856.)

You may refer to below thread to see if can help:
Pcie driver smmu error - Jetson & Embedded Systems / Jetson TX2 - NVIDIA Developer Forums
How to disable SMMU in Jetpack 4.2 - Jetson & Embedded Systems / Jetson TX2 - NVIDIA Developer Forums