devbios port to MTD

[Jeremy Jackson]

Hi,

I've been hacking away for a few days at the devbios code, my goal being
to port it to the MTD framework.  Apart from being "the right thing" in
my opinion, as well as in the devbios TODO, it solves a few practical
problems:

It will let BIOS EEPROMS or DoC be programmed in a network card socket
(eepro100 only just now with Eric Biederman's patch - PLCC32 socket.  I
want to do tulip next so I have a DIP32 as well) to avoid having to swap
chips with the power on.

It also lets the BIOS chip be made read-only, yet have a DoC that is R/W
(well they have to be).

And many more.

So far I have refactored devbios to eliminate global variables (void
*bios), and static flashdevice structures.  The flash probing routine is
now a separate "library", which can use devbios flash_{readb,writeb}, or
when linked into MTD, will use the map driver's access routines.  The
MTD chip driver which uses the probe routine is about half done.  Any
enhancements to the devbios probe routine "library" will automatically
enhance the MTD chip probe routine as well.

I plan to make map drivers out of the devbios pcisets.c code in a
similar manner.

I'm posting this to elicit comments from the respective parties, words
of wisdom, cautions, etc.

I will post the initial devbios refactoring patch once I've checked it
over again.

Regards,

Jeremy

[Stefan Reinauer]

Hi Jeremy
> I've been hacking away for a few days at the devbios code, my goal being
> to port it to the MTD framework.  Apart from being "the right thing" in
> my opinion, as well as in the devbios TODO, it solves a few practical
> problems:

[..]

great! It is definintely "the right thing to do", as it unifies the 
two projects, providing the users one interface instead of the 
3 flash devices - 3 drivers mentality. MTD has the far better concept
as devbios evolved from the old idea of just not having to use a
DOS bootdisk for flashing my mainboard. Also, MTD has a much bigger
userbase, being less specific than devbios is.
> So far I have refactored devbios to eliminate global variables (void
> *bios), and static flashdevice structures.

Good idea. It it's one of the ugly things that survived the time when
the system firmware chip was the only flash device in my system.
> The flash probing routine is
> now a separate "library", which can use devbios flash_{readb,writeb}, or
> when linked into MTD, will use the map driver's access routines.  The
> MTD chip driver which uses the probe routine is about half done.  Any
> enhancements to the devbios probe routine "library" will automatically
> enhance the MTD chip probe routine as well.
> I plan to make map drivers out of the devbios pcisets.c code in a
> similar manner.

If there's not a big objection from the MTD developers, I'd vote for
including the devbios rudiments into MTD completely, allowing it to
be included in the Linux Kernel some day. I'm sure nobody has anything
against getting rid of the devbios device interface stuff in favour
of this unification.
> I'm posting this to elicit comments from the respective parties, words
> of wisdom, cautions, etc.
> I will post the initial devbios refactoring patch once I've checked it
> over again.

I'm willing to help and contribute hints and code wherever i can.

Stefan