Re: [Qemu-arm] [PATCH v6 1/2] hw/arm: Add arm SBSA reference machine, skeleton part

[Ard Biesheuvel]

On Mon, 18 Mar 2019 at 03:39, Hongbo Zhang <address@hidden> wrote:
>
> On Fri, 15 Mar 2019 at 18:41, Ard Biesheuvel <address@hidden> wrote:
> >
> > On Fri, 15 Mar 2019 at 11:08, Hongbo Zhang <address@hidden> wrote:
> > >
> > > For the Aarch64, there is one machine 'virt', it is primarily meant to
> > > run on KVM and execute virtualization workloads, but we need an
> > > environment as faithful as possible to physical hardware, for supporting
> > > firmware and OS development for pysical Aarch64 machines.
> > >
> > > This patch introduces new machine type 'sbsa-ref' with main features:
> > >  - Based on 'virt' machine type.
> > >  - A new memory map.
> > >  - CPU type cortex-a57.
> > >  - EL2 and EL3 are enabled.
> > >  - GIC version 3.
> > >  - System bus AHCI controller.
> > >  - System bus EHCI controller.
> >
> > Hello Hongbo,
> >
> > Apologies for bringing this up now, but I seem to remember that the
> > EHCI does not support 64-bit DMA. Did you run into any issues with
> > this? Or was this fixed in QEMU in the mean time?
> >
> Hi Ard,
> Which EHCI do you mean?
> This time I use a newly introduced system bus EHCI, commit 114529f7
> and I only tested USB mouse and key board, didn't test DMA function.
>

The host controller doesn't work without DMA, so if mouse and keyboard
worked for you, and no DRAM exists below the 4 GB mark, this has
apparently been fixed in QEMU.