qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: WANG Xuerui <i.qemu@xen0n.name>
To: gaosong <gaosong@loongson.cn>
Cc: peter.maydell@linaro.org, thuth@redhat.com,
	chenhuacai@loongson.cn, maobibo@loongson.cn,
	alex.bennee@linaro.org,
	Richard Henderson <richard.henderson@linaro.org>,
	qemu-devel@nongnu.org, yangxiaojuan@loongson.cn,
	laurent@vivier.eu, alistair.francis@wdc.com, peterx@redhat.com,
	pbonzini@redhat.com, bmeng.cn@gmail.com, philmd@redhat.com,
	f4bug@amsat.org
Subject: Re: [PATCH v6 00/21] Add LoongArch linux-user emulation support
Date: Thu, 23 Sep 2021 12:26:44 +0800	[thread overview]
Message-ID: <f2e3705c-fd39-b2ca-8594-ed853a563552@xen0n.name> (raw)
In-Reply-To: <3eda6317.876e.17c10a0dc88.Coremail.gaosong@loongson.cn>

Hi Song,

On 9/23/21 11:09, gaosong wrote:
> > 
> > - How would you provide the necessary firmware bits? Ideally that would 
> > be some open-source reference implementation so people would be able to 
> > collaborate on that front, and to maybe customize for specialized needs 
> > (e.g. ultra-dense cloud use cases like with Firecracker).
> > 
>
> On QEMU, we only support 64 bit, So far, we have no plan to support 32 bit.
IMO it's fine to not support 32-bit for now.
> As far as I know, LoongArch BIOS is planning to open source.
And that's exciting to hear! Really looking forward to that.
> > - How is old/new kernel ABI affecting your system-level emulation 
> > compatibility? IIUC the underlying ISA and chip behavior should be the 
> > same, only difference would be the firmware-kernel ABI, but again it 
> > should be just a matter of substituting the right image.
> >
>
> We only supoort the lastet kernel [1].
>
> [1] https://github.com/loongson/linux/tree/loongarch-next
I may formed the question ambiguously; I'm actually interested in what 
kernel flavor qemu will support emulating, not what qemu runs on. IIUC 
qemu will compile and run fine on both old-world and new-world systems. 
But anyway, we'll find out when your code is out for review.
> > - Would the resulting work support emulating both old-world and 
> > new-world systems? AFAIK those commercial distros who're VERY early 
> > adopters of LoongArch are given similarly early toolchains/kernels. They 
> > belong to the old-world as a result, and are very likely to be stuck on 
> > the old-world ABI for whole major versions before migrating, if at all 
> > possible. Closed-source/commercial software also risk being available 
> > only for the old-world, and it would be extremely important to provide 
> > some degree of interoperability so that we don't split the ecosystem.
>
> On the basis of supporting the latest kernel, we will try to be compatible with the old version of LoongArch.
> But the result may be incompatible。
Thanks for the clarification. Indeed focusing on new-world should be the 
right way to go, adding old-world compatibility later if possible. I 
fear adding compatibility too early would result in a franken-port not 
serving either world well nor maintainable.


  reply	other threads:[~2021-09-23  4:27 UTC|newest]

Thread overview: 33+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-17  8:12 [PATCH v6 00/21] Add LoongArch linux-user emulation support Song Gao
2021-09-17  8:12 ` [PATCH v6 01/21] target/loongarch: Add README Song Gao
2021-09-20 18:51   ` Richard Henderson
2021-09-17  8:12 ` [PATCH v6 02/21] target/loongarch: Add core definition Song Gao
2021-09-20 18:55   ` Richard Henderson
2021-09-17  8:12 ` [PATCH v6 03/21] target/loongarch: Add main translation routines Song Gao
2021-09-17  8:12 ` [PATCH v6 04/21] target/loongarch: Add fixed point arithmetic instruction translation Song Gao
2021-09-17  8:12 ` [PATCH v6 05/21] target/loongarch: Add fixed point shift " Song Gao
2021-09-17  8:12 ` [PATCH v6 06/21] target/loongarch: Add fixed point bit " Song Gao
2021-09-17  8:12 ` [PATCH v6 07/21] target/loongarch: Add fixed point load/store " Song Gao
2021-09-17  8:12 ` [PATCH v6 08/21] target/loongarch: Add fixed point atomic " Song Gao
2021-09-17  8:12 ` [PATCH v6 09/21] target/loongarch: Add fixed point extra " Song Gao
2021-09-17  8:12 ` [PATCH v6 10/21] target/loongarch: Add floating point arithmetic " Song Gao
2021-09-20 18:56   ` Richard Henderson
2021-09-17  8:12 ` [PATCH v6 11/21] target/loongarch: Add floating point comparison " Song Gao
2021-09-17  8:12 ` [PATCH v6 12/21] target/loongarch: Add floating point conversion " Song Gao
2021-09-17  8:12 ` [PATCH v6 13/21] target/loongarch: Add floating point move " Song Gao
2021-09-17  8:12 ` [PATCH v6 14/21] target/loongarch: Add floating point load/store " Song Gao
2021-09-17  8:12 ` [PATCH v6 15/21] target/loongarch: Add branch " Song Gao
2021-09-17  8:12 ` [PATCH v6 16/21] target/loongarch: Add disassembler Song Gao
2021-09-17  8:12 ` [PATCH v6 17/21] LoongArch Linux User Emulation Song Gao
2021-09-23  6:53   ` Laurent Vivier
2021-09-23  8:42     ` Song Gao
2021-09-17  8:12 ` [PATCH v6 18/21] default-configs: Add loongarch linux-user support Song Gao
2021-09-17  8:12 ` [PATCH v6 19/21] target/loongarch: Add target build suport Song Gao
2021-09-17  8:12 ` [PATCH v6 20/21] target/loongarch: 'make check-tcg' support Song Gao
2021-09-17  8:13 ` [PATCH v6 21/21] scripts: add loongarch64 binfmt config Song Gao
2021-09-20 21:17 ` [PATCH v6 00/21] Add LoongArch linux-user emulation support Richard Henderson
2021-09-22  6:22   ` Song Gao
2021-09-22  9:49     ` WANG Xuerui
2021-09-23  3:09       ` gaosong
2021-09-23  4:26         ` WANG Xuerui [this message]
2021-09-23  8:54 ` Song Gao

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=f2e3705c-fd39-b2ca-8594-ed853a563552@xen0n.name \
    --to=i.qemu@xen0n.name \
    --cc=alex.bennee@linaro.org \
    --cc=alistair.francis@wdc.com \
    --cc=bmeng.cn@gmail.com \
    --cc=chenhuacai@loongson.cn \
    --cc=f4bug@amsat.org \
    --cc=gaosong@loongson.cn \
    --cc=laurent@vivier.eu \
    --cc=maobibo@loongson.cn \
    --cc=pbonzini@redhat.com \
    --cc=peter.maydell@linaro.org \
    --cc=peterx@redhat.com \
    --cc=philmd@redhat.com \
    --cc=qemu-devel@nongnu.org \
    --cc=richard.henderson@linaro.org \
    --cc=thuth@redhat.com \
    --cc=yangxiaojuan@loongson.cn \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).