Re: Help me grok the ath(4) device attach code

On Sun, 11 Jun 2023 at 18:17, John Nielsen <lists@jnielsen.net> wrote:

> > On May 30, 2023, at 11:17 PM, Adrian Chadd <adrian@freebsd.org> wrote:
> >
> > There's known issues with all the Atheros chips (sigh) with how the
> EEPROM and PCIe bus reset .. interact.
> > (If the bus reset is too short then the EEPROM state machine gets stuck
> and nothing gets read.) It makes debugging this hard because the NIC itself
> will work in another device fine, because it's the BIOS/ACPI code. :(
>
> Does “nothing gets read” manifest as getting zeroes back? That does appear
> to be what’s happening on my laptop:
>

Yeah that's not a good sign.


>
> Trying (2) EEPROM access at address 0x03ff
> ar9300_eeprom_restore_internal_address: Found block at 3ff: code=0 ref=0
> length=0 major=0 minor=0
> ar9300_eeprom_restore_internal_address: word[0]=0x00 word[1]=0x00
> word[2]=0x00 word[3]=0x00
> ar9300_eeprom_restore_internal_address: checksum 0 0
> ar9300_eeprom_restore_internal_address: EEPROM structure size mismatch
> memory=1088 eeprom=0
>
> Are there any workarounds (even gross ones like sleeping 2 seconds
> somewhere)?
>
>
The gross workaround is to manually reset the pcie RC/EP and do it for the
right amount of time. ;-)



-a