re: SATA port multiplier support

[matthew green <mrg%eterna.com.au@localhost>]

> 2) integrate PMP support to the atabus layer and support attaching more
>   than 2 devices to atabus.

i like this idea better, glad you went that route.

> So I went with 2). This requires one major change to the ata layer:
> struct ata_channel's ch_drive[] can be as large as 15, so it's better to
> dynamically allocate it. As struct ata_channel is allocated in the
> controller driver it requires change to a lot of controller drivers.
> I added helper functions atabus_alloc_drives() and atabus_free_drives()
> for this.

this will also make it easy to fix the svwsata(4) driver's 8 port
support in a simple way (we discussed the problem in email if you
recall.)  great!


.mrg.