Tejun Heo wrote:

Hello, Mark.

Mark Lord wrote:

quoted

Mark Lord wrote:

quoted

An alternative to all this, might be to expose the "select_pmp()"
function shown in the sample code, and have libata-pmp.c call that,
instead of having the new new .pmp_{read,write} functions. 

..

I wonder if this might be more viable than first thought.

Say the LLD, be it ata_piix or sata_mv or sata_svw, were to provide
an option ata_operations method for "select_pmp_port(pmp)",
which the core could invoke prior to any direct manipulation
of the shadow registers.

I don't really think that's a good solution.  That's the quickest
solution for sata_mv but it just works around more fundamental problem
of assuming SFF behavior in core layer which we need to drop anyway.

quoted

I really would like to keep the LLD code small, and have good solid
core routines for non-hardware specific functionality.  All of this stuff
I'm beginning to do with sata_mv would be trivial if I wanted to bloat
the LLD, but really.. only a tiny bit of it need be custom to sata_mv.

The existing SFF reset/probe/pmp stuff is just about exactly what
sata_mv needs.. and I feel a strong desire to not clone/duplicate
that hard-won functionality.

I strongly agree but am having difficult time agreeing with the proposed
approach.

..

Okay, then.  MASSIVE code-duplication, here I come!

-ml