Hi Kevin, I plan to have the default CBFS contain only coreboot and SeabIOS and a few payloads (coreinfo, memtest86, PXE) that I don't intend to change often. That would be protected with a hash and would be kept small for performance reasons. ChromeOS appears to do something similar and take it a step further and write-protect that "read only" region of flash.
The other CBFS would contain larger images that I'm likely to change, such as Linux. There is a chance of name conflicts and that may cause problems. In my use case, the answer is "don't do that". >From a random sampling of FMD files in the coreboot tree (google/glados/chromeos.fmd), I see that ChromeOS uses three: FW_MAIN_A, FW_MAIN_B, and the default COREBOOT. Assuming FW_MAIN_A and FW_MAIN_B contain files with similar names, that would cause confusion if they use SeaBIOS. But I think that ChromeOS is switching to use the Depthcharge bootloader. So, maybe this wouldn't work well for everyone. Ben On Thu, Mar 10, 2016 at 9:10 AM, Kevin O'Connor <[email protected]> wrote: > On Wed, Mar 09, 2016 at 12:19:43PM -0600, Ben Gardner wrote: >> ROM images with a FMAP may have multiple CBFS. >> Scan all available CBFS so that, say, a SeaBIOS bootable image doesn't >> have to be in the main CBFS. >> >> Coreboot puts the FMAP location in the BOOT_MEDIA_PARAMS entry in the >> coreboot table. We can grab that and can all regions for CBFS files. > > Thanks. Can you provide some additional background information on how > this is intended to work. If multiple CBFS locations are found, is > there a chance of file name conflicts? Is the fmap stuff used for > primary/backup rom images and if so how will seabios account for that > if it scans both images? > > Also, can you describe the high level use case you had in mind. > > -Kevin _______________________________________________ SeaBIOS mailing list [email protected] https://www.coreboot.org/mailman/listinfo/seabios
