I just wanted to report that all operations (read/erase/write) work fine on SST49LF040.
I may run an old version, but I saw there is a "?" in the table on your website for "write" on this chip.
# ../flashrom-0.9.2/flashrom -w build/coreboot.rom flashrom v0.9.2-r1001 on Linux 3.4.63-2.44-desktop (x86_64), built with libpci 2.2.3, GCC 4.1.2 20080704 (Red Hat 4.1.2-46) flashrom is free software, get the source code at http://www.flashrom.org
coreboot table found at 0xbffee000. Found chipset "AMD AMD8111", enabling flash write... OK. This chipset supports the following protocols: Non-SPI. Calibrating delay loop... OK. Found chip "SST SST49LF040" (512 KB, LPC) at physical address 0xfff80000. === This flash part has status UNTESTED for operations: PROBE READ ERASE WRITE The test status of this chip may have been updated in the latest development version of flashrom. If you are running the latest development version, please email a report to flashrom@flashrom.org if any of the above operations work correctly for you with this flash part. Please include the flashrom output with the additional -V option for all operations you tested (-V, -Vr, -Vw, -VE), and mention which mainboard or programmer you tested. Thanks for your help! === Writing flash chip... Erasing flash chip... SUCCESS. Programming page: DONE!ss: 0x0007f000 COMPLETE. Verifying flash... VERIFIED.