Am 26.09.2017 02:20 schrieb One7two99 via coreboot:
Hello,
I tried to flash the 8 MB Chip on my X230, but it didn't worked out.
Me: what do I need to do to flash the 2nd (8MB) chip.
If the 1st chip contains the last 4MB of the file, I assume the correct command could be:
dd of=chip8mb.rom bs=1M if=build/coreboot.rom count=8
Is this correct? If this is right I'll add this to the wiki as soon as I have write permissions.
I've dd'ed the first 8MB of the coreboot.rom file with the above command and flashed it on the 8MB chip, but when booting my machine only illuminated the on-off-button for a second before it dies.
When reflashing the 8MB chip with the stock image which I grabbed before will bring my laptop back to life. As such it seems that there must be another was two flash both chips and to strip the coreboot.rom image.
Any ideas what went wrong?
As all howto's I've found so far, which cover the flashing of only the upper 4 MB Chip, the question is also, if someone has already flashed both chips and what (s)he did to make it work.
what would you want to do? Analyse the image. If your BIOS fits in 4MB, you really only need to flash the last 4MB, and using a hardware flasher, you cut it out and flash it to the one 4MB chip. done.
The first 8MB contain the ME. So if you want to, read it, run me_cleaner on it or whatever and flash it back. You will never need it for updating coreboot as long as the BIOS is less than 4MB, which it easily is, say, when you have only seaBIOS as your payload.
The wiki also contains an image file which is useful when you want to try to flash from a running system in software, using flashrom. I don't recommend doing that though. I can't say why, but my X230 died after flashing a few times from a running Debian with flashrom. I couldn't bring it back to life using the saved vendor bios image.
Martin Kepplinger wrote:
what would you want to do? Analyse the image. If your BIOS fits in 4MB, you really only need to flash the last 4MB, and using a hardware flasher, you cut it out and flash it to the one 4MB chip. done.
"BIOS fits" means: if the allocated space for BIOS (as opposed to ME and all other things in the 12 MB of flash) is 4 MB, as determined by the IFD.
The CBFS should then be that same size, because it is the container for the replacement that goes into the BIOS allocation.
Making CBFS 12 MB large because there is 12 MB flash, but only flashing a third of the CBFS because the BIOS allocation is 4 MB is not right.
Since the allocation of the 12 MB of flash is not (yet) changed, I think the CBFS should be 4 MB.
//Peter