ofw/tokenizer/readme.pci

The following table defines the data structure that precedes the FCode
image in a PCI expansion ROM. Refer to the "PCI Local Bus Specification"
for exact descriptions of all the fields.

Note: all values are in hex. Muti-byte values are little-endian.

Offset	Length	Value	Description
------	------	-----	-----------
00	 1	55	ROM Signature, byte 1
01	 1	aa	ROM Signature, byte 2
02	 2	0034	FCode start offset
04	14	00	Reserved
18	 2	001a	PCI Data Structure offset
1a	 4	'PCIR'	PCI Data Structure signature
1e	 2	--	Vendor ID
20	 2	--	Device ID
22	 2	--	VPD offset (usually zero)
24	 2	0018	PCI Data Structure length
26	 1	00	PCI Data Structure revision
27	 3	--	Class Code
2a	 2	--	Image length in 512-byte blocks
2c	 2	--	Revision of code/data
2e	 1	01	Code type (1 = FCode)
2f	 1	80	Continuation Indicator (Bit 7: 1=last image, 0=more)
30	 2	0000	Reserved
32	 2	0000	Padding
34	--	--	FCode image

The following code fragment should precede "fcode-versionN" in the 
source file, in order to make the header:

hex
tokenizer[
   55 emit-byte aa emit-byte	\ PCI magic number
   34 emit-byte 00 emit-byte	\ Start of FCode
   14 0 do 0 emit-byte loop
   1a emit-byte 00 emit-byte	\ Start of PCI Data Structure:
   ascii P emit-byte ascii C emit-byte ascii I emit-byte ascii R emit-byte
   xx emit-byte xx emit-byte	\ 2 vendor
   xx emit-byte xx emit-byte	\ 2 device
   00 emit-byte 00 emit-byte	\ 2 VPD
   18 emit-byte 00 emit-byte	\ 2 DS len
   00 emit-byte xx emit-byte	\ 1 rev
   xx emit-byte xx emit-byte	\ 3 class code
   xx emit-byte xx emit-byte	\ 2 image len
   01 emit-byte 00 emit-byte	\ 2 rev of code
   01 emit-byte 		\ 1 code type
   80 emit-byte 		\ 1 indicator
   00 emit-byte 00 emit-byte	\ 2 reserved
   00 emit-byte 00 emit-byte	\ 2 pad
]tokenizer