[coreboot] GSoC project(SCSI boot)__status report

[Joseph Smith]

> -----Original Message-----
> From: Zhang Rui [mailto:zrfail at gmail.com]
> Sent: Wednesday, June 18, 2008 9:38 PM
> To: Marc Jones
> Cc: Joseph Smith; Stefan Reinauer; Kevin O'Connor; Coreboot
> Subject: Re: [coreboot] GSoC project(SCSI boot)__status report
> 
> What I am going to do is:
> 1. copy LegacyBIOS codes to 0xf0000,
> 2. call a modifid post() in LegacyBIOS to initialize the memory and
> return to coreboot.
> 3. initialize the SCSI controller and install a handler.
> 
> Is that OK?

Well,
Sorry to say, to me that does not make very much sense.
First of all, at the point where you "1. copy LegacyBIOS codes to 0xf0000"
the memory should already be initialized by coreboot correct?? This is one
of the first things coreboot does is initialize the memory. So, the second
part of number 2. ("initialize the memory") may not be necessary if the
memory is already initialized by coreboot.

Here is what I would suggest, I don't know if it is the right direction, but
I think it logically makes sense:

1. Start the coreboot initialization process as normal
2. When coreboot gets to the memory allocation part; have it reserve a
certain amount(Size of LegacyBIOS??) at 0xf0000 (if option LegacyBIOS is
selected).
3. (if option LegacyBIOS is selected) copy LegacyBIOS codes to 0xf0000.
4. (if option LegacyBIOS is selected) Jump to LegacyBIOS and setup any
tables, INT's, etc.
5. Return to coreboot and continue as normal.
6. in the payload part initialize the SCSI controller and install a handler
and call LegacyBIOS INT19.

Does this make any sense, or am I way off course???


Thanks,
Joseph Smith
Set-Top-Linux
www.settoplinux.org