AMD64 Solo Hang - news

[Eric W. Biederman]

Stefan Reinauer <stepan at suse.de> writes:

> Hi,
> 
> it seems that the Solo motherboard is the only motherboard tested so far
> that is based on an Athlon64 instead of Opteron CPUs..
> 
> The following code in src/northbridge/amd/amdk8/misc_control.c relies on
> more than one hypertransport link being available:
> 
>         cmd = pci_read_config32(dev, 0xdc);
>         if((cmd & 0x0000ff00) != 0x02500) {
>                 cmd &= 0xffff00ff;
>                 cmd |= 0x00002500;
>                 pci_write_config32(dev, 0xdc, cmd );
>                 printk_debug("resetting cpu\n");
>                 hard_reset();
>         }
> 
> This implicitly changes CPU0 Link1 FIFO Read Pointer Optimization, not
> taking into regard that LDT1 might not be there.
> 
> It seems this code should rather check all links to see whether they are
> connected and optimize _all_ of the connected.

Agreed. That part should certainly be more dynamic.  It looks like
I missed that when I was syncing the trees.
 
> Is the CPU reset here really needed for the setting to become active?

I'm not certain.  But given that it is playing with hypertransport
link settings I would assume so.  But that is worth confirming.

> The BKDG does not state this explicitly ... (Therefore I vote for
> removing it)

I am starting to agree with you, but there must be some reason it is
in there...

Eric