I'm trying to write a vendor image to flash using a layout file.

It looks like -w expects a full sized flash image even if I'm writing less.

Error: Image size (99224 B) doesn't match the flash chip's size (524288 B)!

Is that normal?  Is there a flag  - would -f work and be safe? 

0:18397 FW0138a1

flashrom unknown on Linux 4.15.0-130-generic (x86_64)
flashrom was built with libpci 3.5.2, GCC 7.5.0, little endian
Command line (11 args): ./flashrom -VV --programmer vl805 --layout /home/jmorrison/VL805/firmware/layout --image FW0138a1 -w /home/jmorrison/VL805/firmware/vl805_fw_0138a1.bin -o test6.log
romlayout 00000000 - 00018397 named FW0138a1
Using region: "FW0138a1".
Using clock_gettime for delay loops (clk_id: 1, resolution: 1ns).
Initializing vl805 programmer
Found "VIA VL805" (1106:3483, BDF 01:00.0).
This PCI device is UNTESTED. Please report the 'flashrom -p xxxx' output
to flashrom@flashrom.org if it works for you. Please add the name of your
PCI device to the subject. Thank you for your help!