On 1 October 2013 20:22, Gerd Hoffmann <kra...@redhat.com> wrote: > On Di, 2013-10-01 at 19:55 +0900, Peter Maydell wrote: >> No documentation or definition of what the semantics of >> specifying a "firmware image" filename are? > > "-machine firmware=$file" has the same effect as "-bios $file", which is > simliar to '-machine kernel=$file' and '-kernel $file'.
It's similar in that it has semantics that might vary between target cpu architecture or even between target machines, and which aren't very well documented... -bios we're stuck with because it's a legacy option, but if we're going to change/augment the syntax here it would be good to be sure that we end up with something that's (a) consistent across boards/architectures (b) not going to turn into another awkward legacy option. >> Why is this a machine option rather than a property of >> the ROM/flash device? > > Not all machines have a flash device. No, but they must have *something* that the firmware code lives in... > Also flash drives don't want a > simple (readonly) image file but a (writable) blockdev as backing > storage, at least the pflash device emulation I've briefly looked at. ...so how does this work for machines where the firmware lives in a flash device? Does -firmware=foo override setting the backing image for the flash device, or vice versa, or do machines with flash devices not support -firmware=foo, or something else? -- PMM
