RE: ARCH=hexagon unsupported?

["Brian Cain" <bcain@codeaurora.org>]

> -----Original Message-----
> From: Arnd Bergmann <arnd@kernel.org>
> Sent: Friday, April 23, 2021 4:37 AM
> To: Nick Desaulniers <ndesaulniers@google.com>
> Cc: open list:QUALCOMM HEXAGON... <linux-hexagon@vger.kernel.org>;
> clang-built-linux <clang-built-linux@googlegroups.com>; Brian Cain
> <bcain@codeaurora.org>; linux-arch <linux-arch@vger.kernel.org>; Guenter
> Roeck <linux@roeck-us.net>
> Subject: Re: ARCH=hexagon unsupported?
> 
> On Fri, Apr 23, 2021 at 12:12 AM 'Nick Desaulniers' via Clang Built Linux
> <clang-built-linux@googlegroups.com> wrote:
> >
> > Arnd,
> > No one can build ARCH=hexagon and
> > https://github.com/ClangBuiltLinux/linux/issues/759 has been open for
> > 2 years.
> >
> > Trying to build
> > $ ARCH=hexagon CROSS_COMPILE=hexagon-linux-gnu make LLVM=1
> LLVM_IAS=1
> > -j71
> >
> > shows numerous issues, the latest of which commit 8320514c91bea
> > ("hexagon: switch to ->regset_get()") has a very obvious typo which
> > misspells the `struct` keyword and has been in the tree for almost 1
> > year.
> 
> Thank you for looking into it.
> 
> > Why is arch/hexagon/ in the tree if no one can build it?
> 
> Removing it sounds reasonable to me, it's been broken for too long, and we
> did the same thing for unicore32 that was in the same situation where the
> gcc port was too old to build the kernel and the clang port never quite work
> in mainline.
> 
> Guenter also brought up the issue a year ago, and nothing happened.
> I see Brian still occasionally sends an Ack to a patch that gets merged through
> another tree, but he has not send any patches or pull requests himself after
> taking over maintainership from Richard Kuo in 2019, and the four hexagon
> pull requests after 2014 only contained build fixes from developers that don't
> have access to the hardware (Randy Dunlap, Viresh Kumar, Mike Frysinger
> and me).

Nick, Arnd,

I can appreciate your frustration, I can see that I have let the community down here.  I would like to keep hexagon in-tree and I am committed to making the changes necessary to do so.  I have a patch under internal review to address the cited build issues and libgcc/compiler-rt content.  In addition, my team has been focusing on developing QEMU system mode support that would mitigate some of the need for having hardware access.  We have landed support for userspace hexagon-linux in upstream QEMU.  My team and I want to make hexagon's open source footprint larger, not smaller.  I realize that not being a good steward of the hexagon kernel has not helped, and we will do what we can to fix it.

-Brian