[U-Boot] [PATCH 12/12] riscv: Add QEMU virt board support

[Bin Meng]

Hi Tuomas,

On Fri, Sep 7, 2018 at 5:03 AM Tuomas Tynkkynen <tuomas.tynkkynen at iki.fi> wrote:
>
> Hi Bin,
>
> On 09/04/2018 12:31 PM, Bin Meng wrote:
> > Hi Lukas,
> >
> > On Tue, Sep 4, 2018 at 5:39 AM Auer, Lukas
> > <lukas.auer at aisec.fraunhofer.de> wrote:
> >>
> >> On Thu, 2018-08-30 at 00:54 -0700, Bin Meng wrote:
> >>> This adds QEMU RISC-V 'virt' board target support, with the hope of
> >>> helping people easily test U-Boot on RISC-V.
> >>>
> >>> The QEMU virt machine models a generic RISC-V virtual machine with
> >>> support for the VirtIO standard networking and block storage devices.
> >>> It has CLINT, PLIC, 16550A UART devices in addition to VirtIO and
> >>> it also uses device-tree to pass configuration information to guest
> >>> software. It implements RISC-V privileged architecture spec v1.10.
> >>>
> >>> Both 32-bit and 64-bit builds are supported. Support is pretty much
> >>> preliminary, only booting to U-Boot shell with the UART driver on
> >>> a single core. Booting Linux is not supported yet.
> >>>
> >>
> >> For your information and to avoid duplicate work, I am working on a
> >> patch set that improves RISC-V support in u-boot. I am currently able
> >> to boot Linux on a multi-core setup in QEMU, but they are not quite
> >> ready to submit yet.
> >>
> >
> > This is great! My next step is to work on virtio driver support in
> > U-Boot as qemu-riscv virt machine has these devices but we don't have
> > corresponding drivers in U-Boot.
> At some point I was working on porting the virtio stack from Linux to
> U-Boot and IIRC got virtio-blk and virtio-net working on ARM. But other
> things consumed my time and I never quite finished that work. Let me
> know if you want to take a look.

This is great. I just finished reading the virtio 1.0 spec and was
about to start the work. My interest was to add virtio-blk and
virtio-net driver to U-Boot too since they are most common devices
(others are not used too much I believe). If you already have the
drivers working, I can help to bring them upstream.

Regards,
Bin