pci function level reset

[Konstantin Belousov]

On Wed, Nov 18, 2020 at 10:27:19AM +0100, Norbert Koch wrote:
> Hello.
> 
> I am running 12.1 on an embedded board which is equipped with an
> intel gbit ethernet controller (Intel PRO/1000, em driver).
> 
> Either the ethernet controller or the bios has a bug, which
> the board manufacturer confirmed.
> 
> After soft reboot gbit ethernet sometimes stops working
> while 100/10mbit are ok.
> Only after power down gbit works again (mostly).
> 
> As they only support windows and linux, their "fix" is writing
> a '1' to /sys/bus/pci/devices/$dev/reset.
> They say this is a "function level reset", whatever this means.
> 
> Is there any way (e.g. using pciconf) to do this under FreeBSD?

devctl reset pci<d>:<b>:<s>:<f>
where d:b:s:f is the pci address of your device.

If device supports FLR, it should do exactly that.