Hi,
On Fri, Jun 26, 2009 at 12:33:14PM +0200, CybFr wrote:
I'd like to re-open a tread from Michal Janke about supporting Dell latitude C610 and its SMSC LPC47N252 SuperIO.
- I've found the closest chip from SMSC was FDC37N972, supported by
superiotool so I added corresponding entries in smsc.c.
- for FDC, UARTS, KBD, RTC, everything seems quite common so I added it in
/superio/smsc/smsssuperio/superio.c. (the big difference betweenn supported smsc chips an LPC47N252 is the EC-8051 core... )
What could be the next step ?
Well, that's the million dollar question. We don't yet support _any_ laptop in coreboot exactly because of the EC problems (well, among other problems).
Luckily, the LPC47N252 datasheet seems to contain some amount of info about the EC, so maybe it's doable. However, we don't know too much about this stuff at this point. Chipset is 830MP which should be doable, so all in all this might be a reasonably well-suited laptop if you want to invest some time and energy into coreboot on this laptop.
I'm also trying to do something similar with an ancient 440BX laptop here, see http://www.coreboot.org/Dell_Latitude_CPi_A366XT, but I haven't gotten very far, yet.
First thing you should do is to get a known-good backup image of your current BIOS, flash that on a different chip and see if the laptop still boots with that. Until this works, I wouldn't recommend to proceed.
Is this a PLCC chip, and is it in a socket or soldered onto the board? If soldered, do you have equipment and skills to desolder it and put on a socket? See http://www.coreboot.org/Soldering_a_socket_on_your_board for PLCC sockets, for other types of chips it may be a bit harder.
Can you make high-res pictures of the whole laptop board (front and back side etc, especially of the Super I/O / EC? We can put those in the wiki also if you want to release them under a freeish license (CC, public domain, etc).
The next step would probably be to find out where the EC code lives in the flash ROM chip, make a coreboot.rom which leaves that area empty and then 'dd' the EC blob over the empty area. Flash that, attach a POST card and/or null-modem cable and see what happens...
Anyway, if you have any superiotool or superio/smsc/smsssuperio/superio.c patches which are generic and could be reused for other stuff, please post them with a Signed-off-by so we can commit them, see http://www.coreboot.org/Development_Guidelines#Sign-off_Procedure
Cheers, Uwe.