Re: [Qemu-riscv] [Qemu-devel] [PATCH v7 00/30] riscv: sifive_u: Improve the emulation fidelity of sifive_u machine

[Bin Meng]

Hi Alistair,

On Thu, Sep 5, 2019 at 3:50 AM Alistair Francis <address@hidden> wrote:
>
> On Sat, Aug 31, 2019 at 7:54 PM Bin Meng <address@hidden> wrote:
> >
> > As of today, the QEMU 'sifive_u' machine is a special target that does
> > not boot the upstream OpenSBI/U-Boot firmware images built for the real
> > SiFive HiFive Unleashed board. Hence OpenSBI supports a special platform
> > "qemu/sifive_u". For U-Boot, the sifive_fu540_defconfig is referenced
> > in the OpenSBI doc as its payload, but that does not boot at all due
> > to various issues in current QEMU 'sifive_u' machine codes.
> >
> > This series aims to improve the emulation fidelity of sifive_u machine,
> > so that the upstream OpenSBI, U-Boot and kernel images built for the
> > SiFive HiFive Unleashed board can be used out of the box without any
> > special hack.
> >
> > The major changes include:
> > - Heterogeneous harts creation supported, so that we can create a CPU
> >   that exactly mirrors the real hardware: 1 E51 + 4 U54.
> > - Implemented a PRCI model for FU540
> > - Implemented an OTP model for FU540, primarily used for storing serial
> >   number of the board
> > - Fixed GEM support that was seriously broken on sifive_u
> > - Synced device tree with upstream Linux kernel on sifive_u
> >
> > OpenSBI v0.4 image built for sifive/fu540 is included as the default
> > bios image for 'sifive_u' machine.
> >
> > The series is tested against OpenSBI v0.4 image for sifive/fu540
> > paltform, U-Boot v2019.10-rc1 image for sifive_fu540_defconfig,
> > and Linux kernel v5.3-rc3 image with the following patch:
> >
> > macb: Update compatibility string for SiFive FU540-C000 [1]
> >
> > OpenSBI + U-Boot, ping/tftpboot with U-Boot MACB driver works well.
> > Boot Linux 64-bit defconfig image, verified that system console on
> > the serial 0 and ping host work pretty well.
> >
> > An OpenSBI patch [2] was sent to drop the special "qemu/sifive_u" platform
> > support in OpenSBI. The original plan was to get the drop patch applied
> > after this QEMU series is merged. However after discussion in the OpenSBI
> > mailing list, it seems the best option for us is to let OpenSBI continue
> > shipping the special "qemu/sifive_u" platform support to work with QEMU
> > version <= 4.1 and deprecate the support sometime in the future. A patch
> > will need to be sent to OpenSBI mailing list to update its document.
> >
> > v4 is now rebased on Palmer's QEMU RISC-V repo "for-master" branch.
> > Dropped the following v3 patch that was already done by someone else.
> > - riscv: sifive_u: Generate an aliases node in the device tree
> > - riscv: sifive_u: Support loading initramfs
>
> I'm having trouble applying this. Do you mind sharing a public git branch?

So I see Palmer has rebased his "for-master" branch against QEMU
master and now this patch series cannot be applied cleanly.

Even worse, the current "for-master" branch has build errors for QEMU RISC-V.

Regards,
Bin