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New ContributorArria 10 - Avalon MM DMA for PCIe crashes the PC when re-initializing the descriptor controller
Hi,
The pin_perst is the power on reset of the FPGA board, when you reboot the host, it will toggle the pin_perst. Where the npor is driven by soft reset (user application), but the soft reset will also bring down the link, once link being bring down, we need to rebooting the PC.
I have a discussion with another PCIe specialty, it seem like there is no other alternative to reset the DMA controller alone beside reboot the PC.
Hope this answered your question.
Regards,
Wincent_Intel
Regular ContributorHi,
The pin_perst is the power on reset of the FPGA board, when you reboot the host, it will toggle the pin_perst. Where the npor is driven by soft reset (user application), but the soft reset will also bring down the link, once link being bring down, we need to rebooting the PC.
I have a discussion with another PCIe specialty, it seem like there is no other alternative to reset the DMA controller alone beside reboot the PC.
Hope this answered your question.
Regards,
Wincent_Intel
New ContributorSad to hear this, but OK.
We are then trying to extend the generated descriptor controller code by a new RESET bit in the control register.
If that doesn't work out for some reason, we can continue to use one of the possible work-arounds:
- Use a fixed IOMMU mapping, so the descriptor addresses stay the same
- or issue a PCIe hot reset before starting the program
- or re-Configure the FPGA before starting the program
- or use a kernel driver instead of UIO/VFIO
