Re: Emulating sd card with hifive_u risc-v machine

[Pascal Scholz]

Hi Alistair,

thanks for your quick and helpful reply. :)

I'll see, if I can try them out on the weekend and will report my results.

Best regards and thanks again!

Pascal

On 08.02.21 23:49, Alistair Francis wrote:
> On Mon, Feb 8, 2021 at 12:00 PM Pascal Scholz
> <s6899329@msx.tu-dresden.de> wrote:
>> Hi all,
>>
>> I'm hoping that I addressed the right mailing lists.
> Hello Pascal,
>
> Yep, this is the right place :)
>
>> I'm working a bit with qemu's risc-v emulation. My current goal is to
>> simulate a complete boot process for the SiFive Unleashed Board (SU 540
>> SoC)[1]. I've created the correspondig OpenSBI and U-Boot images, being
>> the -bios and the -kernel images. It's possible for me to boot up to the
>> U-Boot prompt. From this prompt I now want to boot an system image
>> located on an emulated sd card.
>>
>> However I now fail to get a working sd card within qemu for the device
>> sifive_u. For example i tried the following command:
>>
>> qemu-system-riscv64 -M sifive_u -m 8G -serial stdio -bios
>> build/platform/sifive/fu540/firmware/fw_jump.bin -kernel
>> ../../u-boot/u-boot.bin -device sdhci-pci -device sd-card,drive=sdX
>> -drive id=sdX,if=none,format=raw,file=path/to/image.elf
>>
>> This results in Qemu telling me: -device sdhci-pci: No 'PCI' bus found
>> for device 'sdhci-pci'.
>>
>> Using the machine "virt" the command above works.
>>
>> The thing i tried was:
>>
>> qemu-system-riscv64 -M sifive_u -m 8G -serial stdio -bios
>> opensbi/build/platform/sifive/fu540/firmware/fw_jump.bin -kernel
>> ../u-boot/u-boot.bin -sd path/to/image.elf
>>
>> Resulting in: machine type does not support if=sd,bus=0,unit=0
>>
>>
>> Even if the machine gets stuck at some point when booting, Qemu has no
>> problem starting the VM if I use "-M virt" instead of "-M sifive_u". At
>> this point i think, that the machine "sifive_u" doesn't support sd
>> cards? Is this guess right or is there anything left I can try? After
> Correct. There is no SD card support for the SiFive U in QEMU.
>
> You actually just reminded me though that someone has sent patches to
> add support and I need to review them.
>
> You can find the patches here:
> https://patchew.org/QEMU/20210126060007.12904-1-bmeng.cn@gmail.com/
> which should work when applied to QEMU.
>
> If you do get a chance to test the patches it would be great if you
> can let me know what works/doesn't work for you.
>
> Alistair
>
>> all I'm a bit confused, because there seems to be a block device "sd0"
>> when I try to start the machine "sifive_u" without any additional
>> device/drive arguments. I would really appreciate if someone would tell
>> me, what I'm doing wrong.
>>
>> Thanks in advance and stay healthy!
>>
>> Best regards
>>
>> Pascal
>>
>>
>> [1] https://www.sifive.com/boards/hifive-unleashed
>>
>>