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[V9,0/6] mips: Add Loongson-3 machine support

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Series mips: Add Loongson-3 machine support | expand

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chen huacai Sept. 16, 2020, 2:12 a.m. UTC
Loongson-3 CPU family include Loongson-3A R1/R2/R3/R4 and Loongson-3B
R1/R2. Loongson-3A R1 is the oldest and its ISA is the smallest, while
Loongson-3A R4 is the newest and its ISA is almost the superset of all
others. To reduce complexity, in QEMU we just define two CPU types:

1, "Loongson-3A1000" CPU which is corresponding to Loongson-3A R1. It is
   suitable for TCG because Loongson-3A R1 has fewest ASE.
2, "Loongson-3A4000" CPU which is corresponding to Loongson-3A R4. It is
   suitable for KVM because Loongson-3A R4 has the VZ ASE.

Loongson-3 lacks English documents. I've tried to translated them with
translate.google.com, and the machine translated documents (together
with their original Chinese versions) are available here.

Loongson-3A R1 (Loongson-3A1000)
User Manual Part 1:
http://ftp.godson.ac.cn/lemote/3A1000_p1.pdf
http://ftp.godson.ac.cn/lemote/Loongson3A1000_processor_user_manual_P1.pdf (Chinese Version)
User Manual Part 2:
http://ftp.godson.ac.cn/lemote/3A1000_p2.pdf
http://ftp.godson.ac.cn/lemote/Loongson3A1000_processor_user_manual_P2.pdf (Chinese Version)

Loongson-3A R2 (Loongson-3A2000)
User Manual Part 1:
http://ftp.godson.ac.cn/lemote/3A2000_p1.pdf
http://ftp.godson.ac.cn/lemote/Loongson3A2000_user1.pdf (Chinese Version)
User Manual Part 2:
http://ftp.godson.ac.cn/lemote/3A2000_p2.pdf
http://ftp.godson.ac.cn/lemote/Loongson3A2000_user2.pdf (Chinese Version)

Loongson-3A R3 (Loongson-3A3000)
User Manual Part 1:
http://ftp.godson.ac.cn/lemote/3A3000_p1.pdf
http://ftp.godson.ac.cn/lemote/Loongson3A3000_3B3000usermanual1.pdf (Chinese Version)
User Manual Part 2:
http://ftp.godson.ac.cn/lemote/3A3000_p2.pdf
http://ftp.godson.ac.cn/lemote/Loongson3A3000_3B3000usermanual2.pdf (Chinese Version)

Loongson-3A R4 (Loongson-3A4000)
User Manual Part 1:
http://ftp.godson.ac.cn/lemote/3A4000_p1.pdf
http://ftp.godson.ac.cn/lemote/3A4000user.pdf (Chinese Version)
User Manual Part 2:
I'm sorry that it is unavailable now.

And human-translated documents (W.I.P) are available here now:
https://github.com/loongson-community/docs/tree/master/English-translation-of-Loongson-manual

Both KVM and TCG are available now!

We now already have a full functional Linux kernel (based on Linux-5.4.x
LTS, the kvm host side and guest side have both been upstream for Linux-
5.9, but Linux-5.9 has not been released yet) here:

https://github.com/chenhuacai/linux

Of course the upstream kernel is also usable (though it is "unstable"
now):

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

How to use QEMU/Loongson-3?
1, Download kernel source from the above URL;
2, Build a kernel with arch/mips/configs/loongson3_{def,hpc}config;
3, Boot a Loongson-3A4000 host with this kernel (for KVM mode);
4, Build QEMU-master with this patchset;
5, modprobe kvm (only necessary for KVM mode);
6, Use QEMU with TCG:
       qemu-system-mips64el -M loongson3-virt,accel=tcg -cpu Loongson-3A1000 -kernel <path_to_kernel> -append ...
   Use QEMU with KVM:
       qemu-system-mips64el -M loongson3-virt,accel=kvm -cpu Loongson-3A4000 -kernel <path_to_kernel> -append ...

   The "-cpu" parameter is optional here and QEMU will use the correct type for TCG/KVM automatically.

V1 -> V2:
1, Add a cover letter;
2, Improve CPU definitions;
3, Remove LS7A-related things (Use GPEX instead);
4, Add a description of how to run QEMU/Loongson-3.

V2 -> V3:
1, Fix all possible checkpatch.pl errors and warnings.

V3 -> V4:
1, Sync code with upstream;
2, Remove merged patches;
3, Fix build failure without CONFIG_KVM;
4, Add Reviewed-by: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>.

V4 -> V5:
1, Improve coding style;
2, Remove merged patches;
3, Rename machine name from "loongson3" to "loongson3-virt";
4, Rework the "loongson3-virt" machine to drop any ISA things;
5, Rework "hw/mips: Implement the kvm_type() hook in MachineClass";
6, Add Jiaxun Yang as a reviewer of Loongson-3.

V5 -> V6:
1, Fix license preamble;
2, Improve commit messages;
3, Add hw/intc/loongson_liointc.c to MAINTAINERS;
4, Fix all possible checkpatch.pl errors and warnings.

V7 and V8 have only one patch (machine definition) with some minor improvements.

V8 -> V9:
1, Update KVM type definition from kernel;
2, Fix PageMask with variable page size for TCG;
3, Add TCG support (add Loongson-EXT instructions).

Huacai Chen and Jiaxun Yang (6):
 linux-headers: Update MIPS KVM type defintition
 target/mips: Fix PageMask with variable page size
 target/mips: Add loongson-ext lswc2 group of instructions (Part 1)
 target/mips: Add loongson-ext lswc2 group of instructions (Part 2)
 target/mips: Add loongson-ext lsdc2 group of instructions
 hw/mips: Add Loongson-3 machine support

Signed-off-by: Huacai Chen <chenhc@lemote.com>
---
 default-configs/mips64el-softmmu.mak |   1 +
 hw/mips/Kconfig                      |  11 +
 hw/mips/fw_cfg.c                     |  35 ++
 hw/mips/fw_cfg.h                     |  19 +
 hw/mips/loongson3_virt.c             | 956 +++++++++++++++++++++++++++++++++++
 hw/mips/meson.build                  |   3 +-
 linux-headers/linux/kvm.h            |   5 +-
 target/mips/cp0_helper.c             |  36 +-
 target/mips/cpu.h                    |   1 +
 target/mips/translate.c              | 437 ++++++++++++++++
 10 files changed, 1494 insertions(+), 10 deletions(-)
 create mode 100644 hw/mips/fw_cfg.c
 create mode 100644 hw/mips/fw_cfg.h
 create mode 100644 hw/mips/loongson3_virt.c
--
2.7.0

Comments

Philippe Mathieu-Daudé Sept. 17, 2020, 7:56 a.m. UTC | #1
Hi Huacai,

On 9/16/20 4:12 AM, Huacai Chen wrote:
> Loongson-3 CPU family include Loongson-3A R1/R2/R3/R4 and Loongson-3B
> R1/R2. Loongson-3A R1 is the oldest and its ISA is the smallest, while
> Loongson-3A R4 is the newest and its ISA is almost the superset of all
> others. To reduce complexity, in QEMU we just define two CPU types:
> 
> 1, "Loongson-3A1000" CPU which is corresponding to Loongson-3A R1. It is
>    suitable for TCG because Loongson-3A R1 has fewest ASE.
> 2, "Loongson-3A4000" CPU which is corresponding to Loongson-3A R4. It is
>    suitable for KVM because Loongson-3A R4 has the VZ ASE.
> 
[...]

> Of course the upstream kernel is also usable (though it is "unstable"
> now):
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> 
> How to use QEMU/Loongson-3?
> 1, Download kernel source from the above URL;
> 2, Build a kernel with arch/mips/configs/loongson3_{def,hpc}config;
> 3, Boot a Loongson-3A4000 host with this kernel (for KVM mode);
> 4, Build QEMU-master with this patchset;
> 5, modprobe kvm (only necessary for KVM mode);
> 6, Use QEMU with TCG:
>        qemu-system-mips64el -M loongson3-virt,accel=tcg -cpu Loongson-3A1000 -kernel <path_to_kernel> -append ...
>    Use QEMU with KVM:
>        qemu-system-mips64el -M loongson3-virt,accel=kvm -cpu Loongson-3A4000 -kernel <path_to_kernel> -append ...

Can you add a KVM-only build CI job?
Simply building, not running test, as there is no MIPS CI.

See for example commit 41e1f0e2256 (".travis.yml: Add a KVM-only
s390x job"), but add it to GitLab instead.

Thanks!

Phil.
Aleksandar Markovic Sept. 17, 2020, 8:22 a.m. UTC | #2
On Wednesday, September 16, 2020, Huacai Chen <zltjiangshi@gmail.com> wrote:

> Loongson-3 CPU family include Loongson-3A R1/R2/R3/R4 and Loongson-3B
> R1/R2. Loongson-3A R1 is the oldest and its ISA is the smallest, while
> Loongson-3A R4 is the newest and its ISA is almost the superset of all
> others. To reduce complexity, in QEMU we just define two CPU types:
>
> 1, "Loongson-3A1000" CPU which is corresponding to Loongson-3A R1. It is
>    suitable for TCG because Loongson-3A R1 has fewest ASE.
> 2, "Loongson-3A4000" CPU which is corresponding to Loongson-3A R4. It is
>    suitable for KVM because Loongson-3A R4 has the VZ ASE.
>
> Loongson-3 lacks English documents. I've tried to translated them with
> translate.google.com, and the machine translated documents (together
> with their original Chinese versions) are available here.
>
> Loongson-3A R1 (Loongson-3A1000)
> User Manual Part 1:
> http://ftp.godson.ac.cn/lemote/3A1000_p1.pdf
> http://ftp.godson.ac.cn/lemote/Loongson3A1000_processor_user_manual_P1.pdf
> (Chinese Version)
> User Manual Part 2:
> http://ftp.godson.ac.cn/lemote/3A1000_p2.pdf
> http://ftp.godson.ac.cn/lemote/Loongson3A1000_processor_user_manual_P2.pdf
> (Chinese Version)
>
> Loongson-3A R2 (Loongson-3A2000)
> User Manual Part 1:
> http://ftp.godson.ac.cn/lemote/3A2000_p1.pdf
> http://ftp.godson.ac.cn/lemote/Loongson3A2000_user1.pdf (Chinese Version)
> User Manual Part 2:
> http://ftp.godson.ac.cn/lemote/3A2000_p2.pdf
> http://ftp.godson.ac.cn/lemote/Loongson3A2000_user2.pdf (Chinese Version)
>
> Loongson-3A R3 (Loongson-3A3000)
> User Manual Part 1:
> http://ftp.godson.ac.cn/lemote/3A3000_p1.pdf
> http://ftp.godson.ac.cn/lemote/Loongson3A3000_3B3000usermanual1.pdf
> (Chinese Version)
> User Manual Part 2:
> http://ftp.godson.ac.cn/lemote/3A3000_p2.pdf
> http://ftp.godson.ac.cn/lemote/Loongson3A3000_3B3000usermanual2.pdf
> (Chinese Version)
>
> Loongson-3A R4 (Loongson-3A4000)
> User Manual Part 1:
> http://ftp.godson.ac.cn/lemote/3A4000_p1.pdf
> http://ftp.godson.ac.cn/lemote/3A4000user.pdf (Chinese Version)
> User Manual Part 2:
> I'm sorry that it is unavailable now.
>
> And human-translated documents (W.I.P) are available here now:
> https://github.com/loongson-community/docs/tree/master/
> English-translation-of-Loongson-manual
>
> Both KVM and TCG are available now!
>
> We now already have a full functional Linux kernel (based on Linux-5.4.x
> LTS, the kvm host side and guest side have both been upstream for Linux-
> 5.9, but Linux-5.9 has not been released yet) here:
>
> https://github.com/chenhuacai/linux
>
> Of course the upstream kernel is also usable (though it is "unstable"
> now):
>
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
>
> How to use QEMU/Loongson-3?
> 1, Download kernel source from the above URL;
> 2, Build a kernel with arch/mips/configs/loongson3_{def,hpc}config;
> 3, Boot a Loongson-3A4000 host with this kernel (for KVM mode);
> 4, Build QEMU-master with this patchset;
> 5, modprobe kvm (only necessary for KVM mode);
> 6, Use QEMU with TCG:
>        qemu-system-mips64el -M loongson3-virt,accel=tcg -cpu
> Loongson-3A1000 -kernel <path_to_kernel> -append ...
>    Use QEMU with KVM:
>        qemu-system-mips64el -M loongson3-virt,accel=kvm -cpu
> Loongson-3A4000 -kernel <path_to_kernel> -append ...
>
>    The "-cpu" parameter is optional here and QEMU will use the correct
> type for TCG/KVM automatically.
>
> V1 -> V2:
> 1, Add a cover letter;
> 2, Improve CPU definitions;
> 3, Remove LS7A-related things (Use GPEX instead);
> 4, Add a description of how to run QEMU/Loongson-3.
>
> V2 -> V3:
> 1, Fix all possible checkpatch.pl errors and warnings.
>
> V3 -> V4:
> 1, Sync code with upstream;
> 2, Remove merged patches;
> 3, Fix build failure without CONFIG_KVM;
> 4, Add Reviewed-by: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>.
>
> V4 -> V5:
> 1, Improve coding style;
> 2, Remove merged patches;
> 3, Rename machine name from "loongson3" to "loongson3-virt";
> 4, Rework the "loongson3-virt" machine to drop any ISA things;
> 5, Rework "hw/mips: Implement the kvm_type() hook in MachineClass";
> 6, Add Jiaxun Yang as a reviewer of Loongson-3.
>
> V5 -> V6:
> 1, Fix license preamble;
> 2, Improve commit messages;
> 3, Add hw/intc/loongson_liointc.c to MAINTAINERS;
> 4, Fix all possible checkpatch.pl errors and warnings.
>
> V7 and V8 have only one patch (machine definition) with some minor
> improvements.
>
> V8 -> V9:
> 1, Update KVM type definition from kernel;
> 2, Fix PageMask with variable page size for TCG;
> 3, Add TCG support (add Loongson-EXT instructions).
>
> Huacai Chen and Jiaxun Yang (6):
>  linux-headers: Update MIPS KVM type defintition
>  target/mips: Fix PageMask with variable page size
>  target/mips: Add loongson-ext lswc2 group of instructions (Part 1)
>  target/mips: Add loongson-ext lswc2 group of instructions (Part 2)
>  target/mips: Add loongson-ext lsdc2 group of instructions
>  hw/mips: Add Loongson-3 machine support
>
> Signed-off-by: Huacai Chen <chenhc@lemote.com>
> ---
>  default-configs/mips64el-softmmu.mak |   1 +
>  hw/mips/Kconfig                      |  11 +
>  hw/mips/fw_cfg.c                     |  35 ++
>  hw/mips/fw_cfg.h                     |  19 +
>  hw/mips/loongson3_virt.c             | 956 ++++++++++++++++++++++++++++++
> +++++
>  hw/mips/meson.build                  |   3 +-
>  linux-headers/linux/kvm.h            |   5 +-
>  target/mips/cp0_helper.c             |  36 +-
>  target/mips/cpu.h                    |   1 +
>  target/mips/translate.c              | 437 ++++++++++++++++
>  10 files changed, 1494 insertions(+), 10 deletions(-)
>  create mode 100644 hw/mips/fw_cfg.c
>  create mode 100644 hw/mips/fw_cfg.h
>  create mode 100644 hw/mips/loongson3_virt.c
> --


There should be a suitable note in QEMU documentation describing new
functionality.

Thanks,
Aleksandar



> 2.7.0
>
chen huacai Sept. 21, 2020, 2:19 a.m. UTC | #3
Hi, Aleksandar,

On Thu, Sep 17, 2020 at 4:22 PM Aleksandar Markovic
<aleksandar.qemu.devel@gmail.com> wrote:
>
>
>
> On Wednesday, September 16, 2020, Huacai Chen <zltjiangshi@gmail.com> wrote:
>>
>> Loongson-3 CPU family include Loongson-3A R1/R2/R3/R4 and Loongson-3B
>> R1/R2. Loongson-3A R1 is the oldest and its ISA is the smallest, while
>> Loongson-3A R4 is the newest and its ISA is almost the superset of all
>> others. To reduce complexity, in QEMU we just define two CPU types:
>>
>> 1, "Loongson-3A1000" CPU which is corresponding to Loongson-3A R1. It is
>>    suitable for TCG because Loongson-3A R1 has fewest ASE.
>> 2, "Loongson-3A4000" CPU which is corresponding to Loongson-3A R4. It is
>>    suitable for KVM because Loongson-3A R4 has the VZ ASE.
>>
>> Loongson-3 lacks English documents. I've tried to translated them with
>> translate.google.com, and the machine translated documents (together
>> with their original Chinese versions) are available here.
>>
>> Loongson-3A R1 (Loongson-3A1000)
>> User Manual Part 1:
>> http://ftp.godson.ac.cn/lemote/3A1000_p1.pdf
>> http://ftp.godson.ac.cn/lemote/Loongson3A1000_processor_user_manual_P1.pdf (Chinese Version)
>> User Manual Part 2:
>> http://ftp.godson.ac.cn/lemote/3A1000_p2.pdf
>> http://ftp.godson.ac.cn/lemote/Loongson3A1000_processor_user_manual_P2.pdf (Chinese Version)
>>
>> Loongson-3A R2 (Loongson-3A2000)
>> User Manual Part 1:
>> http://ftp.godson.ac.cn/lemote/3A2000_p1.pdf
>> http://ftp.godson.ac.cn/lemote/Loongson3A2000_user1.pdf (Chinese Version)
>> User Manual Part 2:
>> http://ftp.godson.ac.cn/lemote/3A2000_p2.pdf
>> http://ftp.godson.ac.cn/lemote/Loongson3A2000_user2.pdf (Chinese Version)
>>
>> Loongson-3A R3 (Loongson-3A3000)
>> User Manual Part 1:
>> http://ftp.godson.ac.cn/lemote/3A3000_p1.pdf
>> http://ftp.godson.ac.cn/lemote/Loongson3A3000_3B3000usermanual1.pdf (Chinese Version)
>> User Manual Part 2:
>> http://ftp.godson.ac.cn/lemote/3A3000_p2.pdf
>> http://ftp.godson.ac.cn/lemote/Loongson3A3000_3B3000usermanual2.pdf (Chinese Version)
>>
>> Loongson-3A R4 (Loongson-3A4000)
>> User Manual Part 1:
>> http://ftp.godson.ac.cn/lemote/3A4000_p1.pdf
>> http://ftp.godson.ac.cn/lemote/3A4000user.pdf (Chinese Version)
>> User Manual Part 2:
>> I'm sorry that it is unavailable now.
>>
>> And human-translated documents (W.I.P) are available here now:
>> https://github.com/loongson-community/docs/tree/master/English-translation-of-Loongson-manual
>>
>> Both KVM and TCG are available now!
>>
>> We now already have a full functional Linux kernel (based on Linux-5.4.x
>> LTS, the kvm host side and guest side have both been upstream for Linux-
>> 5.9, but Linux-5.9 has not been released yet) here:
>>
>> https://github.com/chenhuacai/linux
>>
>> Of course the upstream kernel is also usable (though it is "unstable"
>> now):
>>
>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
>>
>> How to use QEMU/Loongson-3?
>> 1, Download kernel source from the above URL;
>> 2, Build a kernel with arch/mips/configs/loongson3_{def,hpc}config;
>> 3, Boot a Loongson-3A4000 host with this kernel (for KVM mode);
>> 4, Build QEMU-master with this patchset;
>> 5, modprobe kvm (only necessary for KVM mode);
>> 6, Use QEMU with TCG:
>>        qemu-system-mips64el -M loongson3-virt,accel=tcg -cpu Loongson-3A1000 -kernel <path_to_kernel> -append ...
>>    Use QEMU with KVM:
>>        qemu-system-mips64el -M loongson3-virt,accel=kvm -cpu Loongson-3A4000 -kernel <path_to_kernel> -append ...
>>
>>    The "-cpu" parameter is optional here and QEMU will use the correct type for TCG/KVM automatically.
>>
>> V1 -> V2:
>> 1, Add a cover letter;
>> 2, Improve CPU definitions;
>> 3, Remove LS7A-related things (Use GPEX instead);
>> 4, Add a description of how to run QEMU/Loongson-3.
>>
>> V2 -> V3:
>> 1, Fix all possible checkpatch.pl errors and warnings.
>>
>> V3 -> V4:
>> 1, Sync code with upstream;
>> 2, Remove merged patches;
>> 3, Fix build failure without CONFIG_KVM;
>> 4, Add Reviewed-by: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>.
>>
>> V4 -> V5:
>> 1, Improve coding style;
>> 2, Remove merged patches;
>> 3, Rename machine name from "loongson3" to "loongson3-virt";
>> 4, Rework the "loongson3-virt" machine to drop any ISA things;
>> 5, Rework "hw/mips: Implement the kvm_type() hook in MachineClass";
>> 6, Add Jiaxun Yang as a reviewer of Loongson-3.
>>
>> V5 -> V6:
>> 1, Fix license preamble;
>> 2, Improve commit messages;
>> 3, Add hw/intc/loongson_liointc.c to MAINTAINERS;
>> 4, Fix all possible checkpatch.pl errors and warnings.
>>
>> V7 and V8 have only one patch (machine definition) with some minor improvements.
>>
>> V8 -> V9:
>> 1, Update KVM type definition from kernel;
>> 2, Fix PageMask with variable page size for TCG;
>> 3, Add TCG support (add Loongson-EXT instructions).
>>
>> Huacai Chen and Jiaxun Yang (6):
>>  linux-headers: Update MIPS KVM type defintition
>>  target/mips: Fix PageMask with variable page size
>>  target/mips: Add loongson-ext lswc2 group of instructions (Part 1)
>>  target/mips: Add loongson-ext lswc2 group of instructions (Part 2)
>>  target/mips: Add loongson-ext lsdc2 group of instructions
>>  hw/mips: Add Loongson-3 machine support
>>
>> Signed-off-by: Huacai Chen <chenhc@lemote.com>
>> ---
>>  default-configs/mips64el-softmmu.mak |   1 +
>>  hw/mips/Kconfig                      |  11 +
>>  hw/mips/fw_cfg.c                     |  35 ++
>>  hw/mips/fw_cfg.h                     |  19 +
>>  hw/mips/loongson3_virt.c             | 956 +++++++++++++++++++++++++++++++++++
>>  hw/mips/meson.build                  |   3 +-
>>  linux-headers/linux/kvm.h            |   5 +-
>>  target/mips/cp0_helper.c             |  36 +-
>>  target/mips/cpu.h                    |   1 +
>>  target/mips/translate.c              | 437 ++++++++++++++++
>>  10 files changed, 1494 insertions(+), 10 deletions(-)
>>  create mode 100644 hw/mips/fw_cfg.c
>>  create mode 100644 hw/mips/fw_cfg.h
>>  create mode 100644 hw/mips/loongson3_virt.c
>> --
>
>
> There should be a suitable note in QEMU documentation describing new functionality.
OK, I will update documentations in V10.

Huacai
>
> Thanks,
> Aleksandar
>
>
>>
>> 2.7.0
chen huacai Sept. 21, 2020, 2:25 a.m. UTC | #4
Hi, Philippe,

On Thu, Sep 17, 2020 at 3:56 PM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>
> Hi Huacai,
>
> On 9/16/20 4:12 AM, Huacai Chen wrote:
> > Loongson-3 CPU family include Loongson-3A R1/R2/R3/R4 and Loongson-3B
> > R1/R2. Loongson-3A R1 is the oldest and its ISA is the smallest, while
> > Loongson-3A R4 is the newest and its ISA is almost the superset of all
> > others. To reduce complexity, in QEMU we just define two CPU types:
> >
> > 1, "Loongson-3A1000" CPU which is corresponding to Loongson-3A R1. It is
> >    suitable for TCG because Loongson-3A R1 has fewest ASE.
> > 2, "Loongson-3A4000" CPU which is corresponding to Loongson-3A R4. It is
> >    suitable for KVM because Loongson-3A R4 has the VZ ASE.
> >
> [...]
>
> > Of course the upstream kernel is also usable (though it is "unstable"
> > now):
> >
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> >
> > How to use QEMU/Loongson-3?
> > 1, Download kernel source from the above URL;
> > 2, Build a kernel with arch/mips/configs/loongson3_{def,hpc}config;
> > 3, Boot a Loongson-3A4000 host with this kernel (for KVM mode);
> > 4, Build QEMU-master with this patchset;
> > 5, modprobe kvm (only necessary for KVM mode);
> > 6, Use QEMU with TCG:
> >        qemu-system-mips64el -M loongson3-virt,accel=tcg -cpu Loongson-3A1000 -kernel <path_to_kernel> -append ...
> >    Use QEMU with KVM:
> >        qemu-system-mips64el -M loongson3-virt,accel=kvm -cpu Loongson-3A4000 -kernel <path_to_kernel> -append ...
>
> Can you add a KVM-only build CI job?
> Simply building, not running test, as there is no MIPS CI.
>
> See for example commit 41e1f0e2256 (".travis.yml: Add a KVM-only
> s390x job"), but add it to GitLab instead.
I have some difficulties in CI testing (I think I should setup a CI
environment first), can this work be done by others, or in future
after this series?

Huacai
>
> Thanks!
>
> Phil.