Re: [PATCH 20/20] target/loongarch: Add linux-user emulation support

From: maobibo <maobibo@loongson.cn>
To: Peter Maydell <peter.maydell@linaro.org>, Song Gao <gaosong@loongson.cn>
Cc: "Thomas Huth" <thuth@redhat.com>,
	"Huacai Chen" <chenhuacai@gmail.com>,
	"Richard Henderson" <richard.henderson@linaro.org>,
	"QEMU Developers" <qemu-devel@nongnu.org>,
	"Laurent Vivier" <laurent@vivier.eu>,
	"Alistair Francis" <alistair.francis@wdc.com>,
	"Paolo Bonzini" <pbonzini@redhat.com>,
	"Philippe Mathieu-Daudé" <philmd@redhat.com>
Subject: Re: [PATCH 20/20] target/loongarch: Add linux-user emulation support
Date: Wed, 30 Jun 2021 09:41:27 +0800	[thread overview]
Message-ID: <5188a660-4bec-45bd-81bc-25dd3ba38f9c@loongson.cn> (raw)
In-Reply-To: <CAFEAcA_swZQG=XCGN4U4XfqrvK2poJw33oEC-5NDFtU3dT1ZuQ@mail.gmail.com>

在 2021年06月29日 21:42, Peter Maydell 写道:
> On Mon, 28 Jun 2021 at 13:05, Song Gao <gaosong@loongson.cn> wrote:
>>
>> Add files to linux-user/loongarch64
>> Add file to default-configs
>> Add loongarch to target/meson.build
>>
>> Signed-off-by: Song Gao <gaosong@loongson.cn>
>> ---
>>  MAINTAINERS                                        |   1 +
>>  default-configs/targets/loongarch64-linux-user.mak |   4 +
>>  include/elf.h                                      |   2 +
>>  linux-user/elfload.c                               |  58 ++++
>>  linux-user/loongarch64/cpu_loop.c                  | 177 ++++++++++++
>>  linux-user/loongarch64/signal.c                    | 193 +++++++++++++
>>  linux-user/loongarch64/sockbits.h                  |   1 +
>>  linux-user/loongarch64/syscall_nr.h                | 307 +++++++++++++++++++++
>>  linux-user/loongarch64/target_cpu.h                |  36 +++
>>  linux-user/loongarch64/target_elf.h                |  14 +
>>  linux-user/loongarch64/target_fcntl.h              |  12 +
>>  linux-user/loongarch64/target_signal.h             |  28 ++
>>  linux-user/loongarch64/target_structs.h            |  49 ++++
>>  linux-user/loongarch64/target_syscall.h            |  46 +++
>>  linux-user/loongarch64/termbits.h                  | 229 +++++++++++++++
>>  linux-user/syscall_defs.h                          |   8 +-
>>  meson.build                                        |   2 +-
>>  qapi/machine-target.json                           |   4 +-
>>  target/loongarch/meson.build                       |  19 ++
>>  target/meson.build                                 |   1 +
>>  20 files changed, 1185 insertions(+), 6 deletions(-)
> 
> This is a massive patch that would benefit from being split up
> into multiple smaller patches.
> 
> I'm told by a kernel developer that loongarch hasn't yet been
> accepted into the Linux kernel mainline. Until it has been, the
> syscall ABI for it is not yet stable, so we won't be able to take
> the linux-user patches for it yet. (We have been burned in the
> past by taking linux-user architecture support patches without
> realizing they weren't for a stable ABI, and then being out of
> sync with the eventual upstream kernel ABI that was accepted.)
> 
> We can certainly do code review in the meantime, though.
Thanks for reviewing the big series patches. It is understandable that
there should be linux kernel merged for one new architecture support
firstly, and then there will be linux-user simulator later.

We are planning to submit patch to linux kernel for LoongArch support,
there is the link:
https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson.git/log/?h=loongarch-next

And we will continueto  submit softmmu support for LoongArch. And is there
any extra requirements for softmmu simulation for new architecture,
such as gcc/binutils/bios?

regards
bibo, mao

> 
> thanks
> -- PMM
> 