[coreboot] SIS630ET coreboot challenge

[Patrick Georgi]

Am 24.05.2010 20:38, schrieb Keith Hui:
> In the spirit of the "coreboot challenge" below, let me propose
> another one: Port coreboot v4 to SIS630ET, then to Asus TUSI-M.
> This is a challenge because most if not all of the SIS chipsets have
> no public documentation, and so far from reversing my factory BIOS I
> don't recognize any of the registers the TUSI-M factory BIOS programs,
> after reading what's available from coreboot v1. To be legally safe, I
> would like one person/team to reverse the factory BIOS of a number of
> 630ET boards, then produce a documentation. Then another person/team
> (can be myself) do the port to that documentation.
Are you aware of SerialICE? It might give you the necessary information
without disassembling other people's code.
With only working from SerialICE logs, you should be safe, as they only
record what happens (but I'm not a lawyer, etc)

As an additional feature, once you got serialice to work for your board
(which requires serial enable, nothing else), you can run vendor bios or
coreboot at wish, without touching the flash again (as the bios is
loaded in the qemu host that controls the target)

This still requires you to make sense of what happens, and in some ways,
it's harder as you only see hardware accesses, not logic decisions (that
is, lots of "inb 0x40 == 0x80", followed by a single "inb 0x40 == 0x81",
instead of "while (inb(0x40)&&1) udelay(1);"), but it's questionable how
much knowledge you _really_ get out of disassembly, too.


Regards,
Patrick