[coreboot] SeaBIOS and the Geode LX framebuffer

Stephen Crocker scrocker at ampltd.com
Tue Oct 7 09:56:24 CEST 2008

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  That is why I was wondering whether a newer
version of the source was available.