Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Sender: bcain=codeaurora.org@mg.codeaurora.org
DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 32E2CC433D3
Reply-To: <bcain@codeaurora.org>
From:   "Brian Cain" <bcain@codeaurora.org>
To:     "'Arnd Bergmann'" <arnd@arndb.de>
Cc:     "'Christoph Hellwig'" <hch@lst.de>,
        "'Linus Torvalds'" <torvalds@linux-foundation.org>,
        "'Sid Manning'" <sidneym@codeaurora.org>,
        "'open list:QUALCOMM HEXAGON...'" <linux-hexagon@vger.kernel.org>,
        "'Linux Kernel Mailing List'" <linux-kernel@vger.kernel.org>
References: <20210623141854.GA32155@lst.de> <08df01d7683d$8f5b7b70$ae127250$@codeaurora.org> <CAK8P3a28_0KJpcLRQrDhFk8-ndxmfk7-Q2_qcRRiYkyh-NNZUQ@mail.gmail.com>
In-Reply-To: <CAK8P3a28_0KJpcLRQrDhFk8-ndxmfk7-Q2_qcRRiYkyh-NNZUQ@mail.gmail.com>
Subject: RE: how can we test the hexagon port in mainline
Date:   Wed, 23 Jun 2021 10:15:19 -0500
Message-ID: <08e101d76842$94f78a60$bee69f20$@codeaurora.org>
MIME-Version: 1.0
Content-Type: text/plain;
        charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Thread-Index: AQJHxj6Ga6VuoE3mNrk9EKW2w3HC7gG6K8dnAg2GTieqIrkNAA==
Content-Language: en-us
Precedence: bulk

> -----Original Message-----
> From: Arnd Bergmann <arnd@arndb.de>
> Sent: Wednesday, June 23, 2021 9:54 AM
> To: Brian Cain <bcain@codeaurora.org>
> Cc: Christoph Hellwig <hch@lst.de>; Linus Torvalds <torvalds@linux-
> foundation.org>; Sid Manning <sidneym@codeaurora.org>; open
> list:QUALCOMM HEXAGON... <linux-hexagon@vger.kernel.org>; Linux Kernel
> Mailing List <linux-kernel@vger.kernel.org>
> Subject: Re: how can we test the hexagon port in mainline
>=20
> On Wed, Jun 23, 2021 at 4:39 PM Brian Cain <bcain@codeaurora.org> =
wrote:
> >
> > > -----Original Message-----
> > > From: Christoph Hellwig <hch@lst.de>
> > ...
> > >
> > > Hi all,
> > >
> > > the oldest supported gcc version in mainline is gcc 4.9.  But the =
only
> > > hexagon crosscompiler I can find is the one Arnds website points =
to here:
> > >
> > > https://mirrors.edge.kernel.org/pub/tools/crosstool/
> > >
> > > which is a non-upstream gcc 4.6.1 port.  How are we supposed to =
even
> > > build test hexagon code?
> >
> > We have provided a clang-12-based toolchain here:
> >
> > https://codelinaro.jfrog.io/artifactory/codelinaro-qemu/2021-05-
> 12/clang+llv
> > m-12.0.0-cross-hexagon-unknown-linux-musl.tar.xz
>=20
> How close is this to the mainline clang builds from =
https://apt.llvm.org/?

This is built from llvm-project 12.0.0 but also contains userspace =
toolchain features like musl and qemu-linux-user for hexagon.  I suppose =
for the purposes of kernel builds they're equivalent.

> The last time we talked, there were still a couple of bugs that =
prevented
> me from building an unmodified kernel with an unmodified clang =
toolchain,
> but I think you planned to address those. Are any changes left that =
did
> not make it into the 12.0 release?

I think those were identified building with clang 12.0.0 or post-12.0.0, =
so I don't think they'll be addressed.  Let me review and follow up on =
the status of those items.  I recall one workaround was to use the =
integrated assembler to avoid one of the toolchain bugs.

> > Could we update https://mirrors.edge.kernel.org/pub/tools/crosstool/ =
to
> > point here?
>=20
> I'm happy to edit the index page on
> https://mirrors.edge.kernel.org/pub/tools/crosstool,
> but could you provide a stable URL that will keep pointing to the =
latest
> version
> in the future so I don't have to update it for each new build?

I don't know how to do that with the mechanisms we have so far.  But I =
will see about getting one created and then hopefully you could use =
that.

-Brian