[coreboot] SeaBIOS and the Geode LX framebuffer
Marc Jones
Marc.Jones at amd.com
Tue Oct 7 17:39:26 CEST 2008
Stephen Crocker wrote:
> Marc Jones wrote:
>> I don't understand that it defaulted to 5530. In sysmgr\sysmgr.h
>> SUPPORT_CS5536 is the targeted chipset. It has been a long time, but
>> SUPPORT_CS5535 should also work. I don't know if SUPPORT_CS5530 would
>> work.
>
> If you look at the link that I posted, you will see why. Here is the
> section of sysmgr.asm in question:
>
> Start:
> ; NOTE: The VSA II installer patches a "JMP SysMgr_Entry" over the
> signature field
> dd VSM_SIGNATURE ; VSM signature
> db VSM_SYS_MGR ; VSM type
> db 0FFh ; Any CPU
> if SUPPORT_CS5535
> dw DEVICE_ID_5535 ; VSA for CS5535
> else
> dw DEVICE_ID_5530 ; VSA for CS5530
> endif
> dw VSA_VERSION ; System Manager version
> dd OFFSET edata ; Size of System Manager
> dw OFFSET SysMgr_Entry ; EntryPoint
> dd OFFSET _end ; DS Limit
> dw 0007h ; Requirements: 4096-byte boundary
> dw VSA_VERSION ; VSA version
>
> As you can see, if SUPPORT_CS5535 is not defined, it will use
> DEVICE_ID_5530. Furthermore, it would appear that there is no way for
> the field to be DEVICE_ID_5536 without modifying the source code.
> Admittedly, this is a trivial patch but it strikes me as odd that such
> an action is required. That is why I was wondering whether a newer
> version of the source was available.
>
Ah, This is an oversite on our part. I don't think that anyone uses that
field in the signature.
Marc
--
Marc Jones
Senior Firmware Engineer
(970) 226-9684 Office
mailto:Marc.Jones at amd.com
http://www.amd.com/embeddedprocessors
More information about the coreboot
mailing list