On Tue, Apr 11, 2023 at 01:14:27PM +0200, Gerd Hoffmann wrote: > > The second approach is the one described in the Ubuntu wiki[3], and > > also requires passing two files to QEMU, except this time they come > > from the opensbi and u-boot-qemu packages respectively. The usage > > looks like > > > > -bios /usr/lib/riscv64-linux-gnu/opensbi/generic/fw_jump.elf > > -kernel /usr/lib/u-boot/qemu-riscv64_smode/uboot.elf > > > > I think in this case the first file is a minimal build of OpenSBI > > that likely just initializes enough hardware before handing control > > to an arbitrary payload - in this case, u-boot. > > Yes. These days opensbi seems to be loaded by default, so the first > line is not needed. In fact I'm running a guest here, on fedora 37 + > virt-preview with just this ... > > <os> > <type arch='riscv64' machine='virt'>hvm</type> > <kernel>/home/kraxel/projects/u-boot/build-qemu-riscv64-smode/u-boot.bin</kernel> > <boot dev='hd'/> > </os> > > ... and it works fine. This matches my experience. I've tried both u-boot.bin (referenced in openSUSE and FreeBSD documentation) and uboot.elf (Debian and Ubuntu documentation) and it doesn't seem to make a difference which one you choose. > There is also this variant ... > > <qemu:commandline> > <qemu:arg value='-drive'/> > <qemu:arg value='if=pflash,index=1,format=raw,file=/vmdisk/hdd/pool-risc-v/RISCV_VIRT.raw'/> > </qemu:commandline> > > ... to boot edk2 firmware. Note this is a single image carrying both > code and vars. Also note 'index=1', which I think is needed because the > (default) opensbi is loaded to the pflash device with 'index=0'. > > This doesn't boot the distro due to grub2 not having full riscv64 efi > support (yet). The openSUSE images are using grub2, and possibly EFI somehow? Right after selecting the entry I see EFI stub: Booting Linux Kernel... EFI stub: Loaded initrd from LINUX_EFI_INITRD_MEDIA_GUID device path EFI stub: Using DTB from configuration table EFI stub: Exiting boot services... The image never manages to boot all the way for me: it looks like it can't find the root filesystem. But eventually I get dropped into a rescue shell, and /sys/firmware/efi/ contains some data. Note that I'm not using edk2 in this case, just the same u-boot.bin file that I've used to boot other images. -- Andrea Bolognani / Red Hat / Virtualization
