Re: [Qemu-riscv] [Qemu-devel] RISC-V: Include ROM in QEMU

[Gerd Hoffmann]

On Fri, Jun 07, 2019 at 05:03:42PM -0700, Palmer Dabbelt wrote:
> On Thu, 06 Jun 2019 16:22:47 PDT (-0700), address@hidden wrote:
> > Hello,
> > 
> > As a test of the waters, how would the QEMU community feel about
> > including the RISC-V OpenSBI project as a ROM submodule?
> > 
> > The idea would be to have OpenSBI (similar to ATF for ARM and a BIOS
> > for x86) included by default to simplify the QEMU RISC-V boot process
> > for users. This would remove the requirement for users/developers to
> > build a RISC-V firmware. The goal here is to allow people to just
> > download and run their kernel as easily as they currently do for x86.
> > 
> > We would make sure that it can be disabled! That is users/developers
> > can use their own (or none) if they want to. The idea here is just to
> > simplify the boot process, not lock anyone out.
> 
> I like it.  My only question is about the mechanics of doing so: are we just
> going to assume there's a cross compiler in PATH?  I guess that's less of a
> usability headache than needing a complier and a firmware.

Usual way to add firmware:

  (1) Add a submodule below roms/
  (2) Add rules to build the firmware to roms/Makefile.  Firmware
      maintainers can use them, and they also document the build process.
      A normal qemu build will not automatically build the firmware
      though.
  (3) Place a pre-built binary in pc-bios/

There is some cross compiler detection logic in roms/Makefile which you
can use.

cheers,
  Gerd