Hi Soeren, On Sun, 30 Jul 2023 at 11:38, Soeren Moch <sm...@web.de> wrote: > > On 30.07.23 19:16, Simon Glass wrote: > > Add some hints and observations related to booting distros on QEMU on x86. > > > > Signed-off-by: Simon Glass <s...@chromium.org> > Simon, > > you cc'd me on this patch (both versions), but I never used u-boot on > x86. What do you expect from my side here?
This is automatic with get_maintainers.pl but I am not sure why it added you. Regards, Simon > > > > (no changes since v1) > > > > doc/board/emulation/qemu-x86.rst | 88 ++++++++++++++++++++++++++++++-- > > 1 file changed, 84 insertions(+), 4 deletions(-) > > > > diff --git a/doc/board/emulation/qemu-x86.rst > > b/doc/board/emulation/qemu-x86.rst > > index e7dd4e994d38..15f56b6bc706 100644 > > --- a/doc/board/emulation/qemu-x86.rst > > +++ b/doc/board/emulation/qemu-x86.rst > > @@ -113,7 +113,87 @@ sure the specified CPU supports 64-bit like '-cpu > > core2duo'. Conversely > > '-cpu pentium' won't work for obvious reasons that the processor only > > supports 32-bit. > > > > -Note 64-bit support is very preliminary at this point. Lots of features > > -are missing in the 64-bit world. One notable feature is the VGA console > > -support which is currently missing, so that you must specify '-nographic' > > -to get 64-bit U-Boot up and running. > > +Booting distros > > +--------------- > > + > > +It is possible to install and boot a standard Linux distribution using > > +qemu-x86_64 by setting up a root disk:: > > + > > + qemu-img create root.img 10G > > + > > +then using the installer to install. For example, with Ubuntu 2023.04:: > > + > > + qemu-system-x86_64 -m 8G -smp 4 -bios /tmp/b/qemu-x86_64/u-boot.rom \ > > + -drive file=root.img,if=virtio,driver=raw \ > > + -drive file=ubuntu-23.04-desktop-amd64.iso,if=virtio,driver=raw > > + > > +You can also add `-serial mon:stdio` if you want the serial console to > > show as > > +well as the video. > > + > > +The output will be something like this:: > > + > > + U-Boot SPL 2023.07 (Jul 23 2023 - 08:00:12 -0600) > > + Trying to boot from SPI > > + Jumping to 64-bit U-Boot: Note many features are missing > > + > > + > > + U-Boot 2023.07 (Jul 23 2023 - 08:00:12 -0600) > > + > > + CPU: QEMU Virtual CPU version 2.5+ > > + DRAM: 8 GiB > > + Core: 20 devices, 13 uclasses, devicetree: separate > > + Loading Environment from nowhere... OK > > + Model: QEMU x86 (I440FX) > > + Net: e1000: 52:54:00:12:34:56 > > + eth0: e1000#0 > > + Hit any key to stop autoboot: 0 > > + Scanning for bootflows in all bootdevs > > + Seq Method State Uclass Part Name > > Filename > > + --- ----------- ------ -------- ---- ------------------------ > > ---------------- > > + Scanning global bootmeth 'efi_mgr': > > + Hunting with: nvme > > + Hunting with: qfw > > + Hunting with: scsi > > + scanning bus for devices... > > + Hunting with: virtio > > + Scanning bootdev 'qfw_pio.bootdev': > > + fatal: no kernel available > > + Scanning bootdev 'virtio-blk#0.bootdev': > > + Scanning bootdev 'virtio-blk#1.bootdev': > > + 0 efi ready virtio 2 virtio-blk#1.bootdev.part > > efi/boot/bootx64.efi > > + ** Booting bootflow 'virtio-blk#1.bootdev.part_2' with efi > > + EFI using ACPI tables at f0060 > > + efi_install_fdt() WARNING: Can't have ACPI table and device tree - > > ignoring DT. > > + efi_run_image() Booting /efi\boot\bootx64.efi > > + error: file `/boot/' not found. > > + > > +Standard boot looks through various available devices and finds the virtio > > +disks, then boots from the first one. After a second or so the grub menu > > appears > > +and you can work through the installer flow normally. > > + > > +Note that standard boot will not find 32-bit distros, since it looks for a > > +different filename. > > + > > +Current limitations > > +------------------- > > + > > +Only qemu-x86-64 can be used for booting distros, since qemu-x86 (the > > 32-bit > > +version of U-Boot) seems to have an EFI bug leading to the boot handing > > after > > +Linux is selected from grub, e.g. with `debian-12.1.0-i386-netinst.iso`:: > > + > > + ** Booting bootflow 'virtio-blk#1.bootdev.part_2' with efi > > + EFI using ACPI tables at f0180 > > + efi_install_fdt() WARNING: Can't have ACPI table and device tree - > > ignoring DT. > > + efi_run_image() Booting /efi\boot\bootia32.efi > > + Failed to open efi\boot\root=/dev/sdb3 - Not Found > > + Failed to load image 큀緃: Not Found > > + start_image() returned Not Found, falling back to default loader > > + Welcome to GRUB! > > + > > +The bochs video driver also seems to cause problems before the OS is able > > to > > +show a display. > > + > > +Finally, the use of `-M accel=kvm` is intended to use the native CPU's > > +virtual-machine features to accelerate operation, but this causes U-Boot > > to hang > > +when jumping 64-bit mode, at least on AMD machines. This may be a bug in > > U-Boot > > +or something else. >
