On Fri, May 7, 2021 at 12:56 AM Marc Kleine-Budde [off-list ref] wrote:

On 22.04.2021 09:18:54, Marc Kleine-Budde wrote:

quoted

On 4/21/21 9:58 PM, Drew Fustini wrote:

quoted

I am encountering similar error with the 5.10 raspberrypi kernel on
RPi 4 with MCP2518FD:

  mcp251xfd spi0.0 can0: CRC read error at address 0x0010 (length=4,
data=00 ad 58 67, CRC=0xbbfd) retrying

What's the situation you see these errors?

I'm not particular happy with that patch, as it only works around that one
particular bit flip issue. If you really hammer the register, the driver will
still notice CRC errors that can be explained by other bits flipping. Consider
this as the first order approximation of a higher order problem :) - the root
cause is still unknown.

quoted

Would it be possible for you to pull these patches into a v5.10 branch
in your linux-rpi repo [1]?

Here you are:

https://github.com/marckleinebudde/linux-rpi/tree/v5.10-rpi/backport-performance-improvements

I've included the UINC performance enhancements, too. The branch is compiled
tested only, though. I'll send a pull request to the rpi kernel after I've
testing feedback from you.

Drew, Patrick, have you tested this branch? If so I'll send a pull
request to the raspi kernel.

Thank you for following up.

I need to build it and send it to the friend who was testing to check
if the CRC errors go away.  He is testing CANFD with a 2021 Ford F150
truck.  I will follow up here once I know the results.

-Drew