Re: Parallel ATA with libata status with the patches I'm working on

Jeff Garzik
2005-11-04T07:00:09Z

Benjamin Herrenschmidt wrote:
>>- HPA
>>- IRQ mask
>
>
> Why do we need the above at all ? It always looked to me like a gross
> hack but then, I don't fully understand what the problem was on those
> old x86 that needed it :)

Not sure about IRQ mask.

For host-protected area (HPA), I've been thinking about a dm-hpa driver,
which libata causes to auto-attach to the libata-discovered disks during
probe.

That gives people full access to the disk (and to the HPA), while
ensuring that there are no partition mismatch issues.

Not sure how well it will work out in practice, but it's worth thinking
about.

If auto-attach/etc. doesn't work, I lean towards defaulting libata to
enable access to the HPA, under the philosophy "export 100% of the
hardware". Then an interested party could create an optional dm-hpa
piece, to split 100%-of-the-hardware into two pieces, one a
partitionable device, and the other, the HPA.

Jeff