On Tue, Nov 03, 2020 at 10:47:10 +0000, Alex Bennée wrote: > We should at least document what this machine is about.
Thanks! (comments below) > Cc: Graeme Gregory <gra...@nuviainc.com> > Cc: Leif Lindholm <l...@nuviainc.com> > Cc: Hongbo Zhang <hongbo.zh...@linaro.org> > Cc: Shashi Mallela <shashi.mall...@linaro.org> > Signed-off-by: Alex Bennée <alex.ben...@linaro.org> > --- > docs/system/arm/sbsa.rst | 30 ++++++++++++++++++++++++++++++ > docs/system/target-arm.rst | 1 + > 2 files changed, 31 insertions(+) > create mode 100644 docs/system/arm/sbsa.rst > > diff --git a/docs/system/arm/sbsa.rst b/docs/system/arm/sbsa.rst > new file mode 100644 > index 0000000000..a47c9360de > --- /dev/null > +++ b/docs/system/arm/sbsa.rst > @@ -0,0 +1,30 @@ > +Arm Server Base System Architecture Reference board (``sbsa-ref``) > +================================================================== > + > +While the `virt` board is a generic board platform that doesn't match > +any real hardware the `sbsa-ref` board intends to look like real > +hardware. The `Server Base System Architecture > +<https://developer.arm.com/documentation/den0029/latest>` defines a > +minimum base line of hardware support and importantly how the firmware > +reports that to any operating system. It is a static system that > +reports a very minimal DT to the firmware for command line input to > +the firmware. I think you mean the right thing, but ... "a very minimal DT to the firmware for non-discoverable information about components affected by the qemu command line" (i.e. cpus and memory) > As a result it must have a firmware specifically built > +to expect a certain hardware layout (as you would in a real machine). > + > +It is intended to be a machine for developing firmware and testing > +standards compliance with operating systems. > + > +Supported devices > +""""""""""""""""" > + > +The sbsa-ref board supports: > + > + - A configurable number of Cortex-A57 cpus > + - GIC version 3 The intent was always for sbsa-ref to be tracking SBSA development, so I wonder whether we should be documenting specific versions of cpu and gic (and then keep remembering to update the docs). My short-term plan was to swap the a57 for "max", but documentation-wise, could we just say "number of aarch64 cpus"? Could we refer to the gic as "latest supported emulated"? / Leif > + - System bus AHCI controller. > + - System bus EHCI controller. > + - CDROM and hard disc on AHCI bus. > + - E1000E ethernet card on PCIE bus. > + - VGA display adaptor on PCIE bus. > + - A generic SBSA watchdog device > + > diff --git a/docs/system/target-arm.rst b/docs/system/target-arm.rst > index fdcf25c237..9636f3fd00 100644 > --- a/docs/system/target-arm.rst > +++ b/docs/system/target-arm.rst > @@ -79,6 +79,7 @@ undocumented; you can get a complete list by running > arm/mps2 > arm/musca > arm/realview > + arm/sbsa-ref > arm/versatile > arm/vexpress > arm/aspeed > -- > 2.20.1 >
