Re: [PATCH 0/4] MdeModulePkg: add support for dispatching foreign arch PE/COFF images

["Kinney, Michael D" <michael.d.kinney@intel.com>]

Ard,

I think there may be a lot of assumptions in this
proposal that are not documented.  

I do not see any description of how an image is 
started or how calls between native code and emulated
code are handled.

Also, are multiple emulated CPUs supported?  It looks
like there can only be one instance of this new protocol.

Can you please provide more detailed comments for the
functions in the new protocol and document the assumptions
and known limitation in the header?

>From one perspective, EBC is an emulated instruction set.
Would it make sense to have EBC be one of the emulated 
CPU types that can be plugged in?

Thanks,

Mike

> -----Original Message-----
> From: Ard Biesheuvel [mailto:ard.biesheuvel@linaro.org]
> Sent: Wednesday, September 12, 2018 6:22 AM
> To: edk2-devel@lists.01.org
> Cc: agraf@suse.de; Ard Biesheuvel
> <ard.biesheuvel@linaro.org>; Zimmer, Vincent
> <vincent.zimmer@intel.com>; Richardson, Brian
> <brian.richardson@intel.com>; Kinney, Michael D
> <michael.d.kinney@intel.com>; Andrew Fish
> <afish@apple.com>; Laszlo Ersek <lersek@redhat.com>;
> Leif Lindholm <leif.lindholm@linaro.org>; Zeng, Star
> <star.zeng@intel.com>; Dong, Eric <eric.dong@intel.com>;
> Ni, Ruiyu <ruiyu.ni@intel.com>
> Subject: [PATCH 0/4] MdeModulePkg: add support for
> dispatching foreign arch PE/COFF images
> 
> Add the basic plumbing to DXE core, the PCI bus driver
> and the boot manager
> to allow PE/COFF images to be dispatched that target an
> architecture that is
> not native for the platform, but which is supported by
> an emulator.
> 
> One implementation of such an emulator can be found
> here:
> https://github.com/ardbiesheuvel/X86EmulatorPkg
> 
> Cc: Zimmer Vincent <vincent.zimmer@intel.com>
> Cc: Brian Richardson <brian.richardson@intel.com>
> Cc: Michael D Kinney <michael.d.kinney@intel.com>
> Cc: Andrew Fish <afish@apple.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Leif Lindholm <leif.lindholm@linaro.org>
> Cc: Star Zeng <star.zeng@intel.com>
> Cc: Eric Dong <eric.dong@intel.com>
> Cc: Ruiyu Ni <ruiyu.ni@intel.com>
> 
> Ard Biesheuvel (4):
>   MdeModulePkg: introduce PE/COFF image emulator
> protocol
>   MdeModulePkg/DxeCore: invoke the emulator protocol for
> foreign images
>   MdeModulePkg/PciBusDxe: invoke PE/COFF emulator for
> foreign option
>     ROMs
>   MdeModulePkg/UefiBootManagerLib: allow foreign
> Driver#### images
> 
>  MdeModulePkg/Bus/Pci/PciBusDxe/PciBus.h       |  1 +
>  MdeModulePkg/Bus/Pci/PciBusDxe/PciBusDxe.inf  |  1 +
>  .../Bus/Pci/PciBusDxe/PciOptionRomSupport.c   | 16
> +++++-
>  MdeModulePkg/Core/Dxe/DxeMain.h               |  3 ++
>  MdeModulePkg/Core/Dxe/DxeMain.inf             |  1 +
>  MdeModulePkg/Core/Dxe/Image/Image.c           | 39
> +++++++++++---
>  .../Include/Protocol/PeCoffImageEmulator.h    | 51
> +++++++++++++++++++
>  .../Library/UefiBootManagerLib/BmLoadOption.c | 26
> +++++++++-
>  .../Library/UefiBootManagerLib/InternalBm.h   |  1 +
>  .../UefiBootManagerLib/UefiBootManagerLib.inf |  1 +
>  MdeModulePkg/MdeModulePkg.dec                 |  4 ++
>  11 files changed, 136 insertions(+), 8 deletions(-)
>  create mode 100644
> MdeModulePkg/Include/Protocol/PeCoffImageEmulator.h
> 
> --
> 2.17.1