SATA hotplug and AHCI

[David Ehrmann]

Bruce M. Simpson wrote:
> Andrey V. Elsukov wrote:
>> ...
>> Linux's libata driver has a quirk for VIA AHCI:
>>
>> /* vt8251 doesn't clear BSY on signature FIS reception,
>>  * request follow-up softreset.
>>  */
>>
>> If i right understand it issues softreset for VIA controllers just
>> after hardreset. And after softreset it is trying to read device 
>> signature.
>>
>> FreeBSD CURRENT has similar code, but it is disabled by default.
>> You can try install CURRENT and rebuild ata_ahci driver with AHCI_PM 
>> option.
>> May be it will help..
>>
>
> I'm glad this came up. When I asked a few weeks ago about SATA Hotplug 
> support, I was asking because of a board with a VIA SATA controller I 
> was planning to add drives too, on a JBOD basis.
>
> Perhaps this hack can be backported to 7.x to actually make VIA 
> controllers useful?
I'm *probably* going to wait for the next release and hope they enable 
the fix.  Having to run atacontrol attach/detach is a little annoying, 
but it seems to work, so for now, I might just say that's good enough.
>
> P.S. VIA's SATA RAID BIOS is a pile of poop, don't bother using VIA 
> for RAID.
I'd say the entire BIOS is.  I had problems getting it to detect boot 
devices for the F11 boot menu.  The were more or less resolved after 
rebooting (so the hardware was no longer new), but still...