> > > 1) qboot optimizations: adopt the fw_cfg DMA interface instead of > > > the > > > cbfs flash hack (so that -kernel works), drop PCI bridge > > > initialization, > > > copy less than 64K of memory from ROM to 0xf0000; > > > > I can do the evaluation on qboot. Also adding Amnon Ilan, to see if > > there is some thing we can do for SeaBios. > > AFAIK latest seabios already supports DMA. > It's easy to add more config options for seabios > if you are so inclined.
Yes, I tried that, the fw_cfg overhead in SeaBios/linuxboot optrom is already not a big issue for us. However, there are still some other code in SeaBIOS needs to be investigated. > > > > > > > > > > > > 2) Linux optimizations: using an uncompressed image to avoid the > > > cost > > > of > > > copying and decompressing. QEMU can already load the image at > > > the > > > right > > > place and the real mode stub can do little more than GDT/IDT > > > setup. > > > > This works surely. I actually followed your suggestion in v1 to > > make > > kernel multiboot-compatible and then load that kernel in QEMU > > directly > > (Also skipped firmware but some changes in patch 11 would move from > > QEMU to guest kernel). This way we also gain benefit of doing mmap > > kernel as you talked below. Not sure if this is something you can > > accpet. > > I'm not sure I understand the question here. Accept what? > I mean loading a multiboot kernel without the need for firmaware. Thanks, Chao
