Re: [PATCH for-5.1 V3 0/7] mips: Add Loongson-3 machine support (with KVM)

[chen huacai]

Hi, Aleksandar,

On Sun, May 3, 2020 at 6:50 PM Aleksandar Markovic
<address@hidden> wrote:
>
> нед, 3. мај 2020. у 12:21 Huacai Chen <address@hidden> је написао/ла:
> >
> > 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.
> >
>
> Huacai, thanks for putting together v3, which is a little better than v2, and
> thanks for addressing my previous suggestions.
>
> Now, give us some time to digest new data on Loongson3.  We will
> respond, but it won't happen immediately, which is, you'd agree,
> reasonable. Just be patient.
>
> But again, in general, I salute your efforts very much!
>
> Yours, Aleksandar
I'm sorry for this late response because I have done many tests to
reproduce the problem reported at
https://patchew.org/QEMU/address@hidden/,
but I don't have such a failure...

What I have done:
1, "make check" on MIPS64 platform (distro is Fedora28 for Loongson);
2, "make check" on X86_64 platform (distro is RHEL8);
3, "make docker-test-quick@centos7 SHOW_ENV=1 NETWORK=1" on X86_64
platform (distro is RHEL8);
4, "make docker-test-quick@centos7 SHOW_ENV=1 J=n NETWORK=1" on X86_64
platform (distro is RHEL8 and I've tried n=2,3,4....14);

I always get the same result:
Not run: 259
Passed all 117 iotests

And, it seems that my patchset doesn't touch anything about iotests,
so I don't know why the build test fails on iotests 192 (Maybe your
build test has the same problem without my patches).

P.S.: I have found a problem that my patchset has a build failure with
CONFIG_KVM=n, but this is another problem and I will send V4 to fix it
(after collecting all problems in V3).


>
> > 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.
> >
> > We are preparing to add QEMU's Loongson-3 support. MIPS VZ extension is
> > fully supported in Loongson-3A R4+, so we at first add QEMU/KVM support
> > in this series. And the next series will add QEMU/TCG support (it will
> > emulate Loongson-3A R1).
> >
> > We already have a full functional Linux kernel (based on Linux-5.4.x LTS
> > but not upstream yet) here:
> >
> > https://github.com/chenhuacai/linux
> >
> > 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;
> > 4, Build QEMU-5.0.0 with this patchset;
> > 5, modprobe kvm;
> > 6, Use QEMU with TCG (available in future):
> >        qemu-system-mips64el -M loongson3,accel=tcg -cpu Loongson-3A1000 
> > -kernel <path_to_kernel> -append ...
> >    Use QEMU with KVM (available at present):
> >        qemu-system-mips64el -M loongson3,accel=kvm -cpu Loongson-3A4000 
> > -kernel <path_to_kernel> -append ...
> >
> >    The "-cpu" parameter can be omitted 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.
> >
> > Huacai Chen(7):
> >  configure: Add KVM target support for MIPS64
> >  hw/mips: Implement the kvm_type() hook in MachineClass
> >  hw/mips: Add CPU IRQ3 delivery for KVM
> >  target/mips: Add Loongson-3 CPU definition
> >  target/mips: Add more CP0 register for save/restor
> >  hw/mips: Add Loongson-3 machine support (with KVM)
> >  MAINTAINERS: Add myself as Loongson-3 maintainer
> >
> > Signed-off-by: Huacai Chen <address@hidden>
> > ---
> >  MAINTAINERS                          |   5 +
> >  configure                            |   2 +-
> >  default-configs/mips64el-softmmu.mak |   1 +
> >  hw/core/Makefile.objs                |   2 +-
> >  hw/core/null-machine.c               |   4 +
> >  hw/mips/Kconfig                      |  10 +
> >  hw/mips/Makefile.objs                |   3 +-
> >  hw/mips/common.c                     |  31 ++
> >  hw/mips/mips_int.c                   |   4 +-
> >  hw/mips/mips_loongson3.c             | 901 
> > +++++++++++++++++++++++++++++++++++
> >  include/hw/mips/mips.h               |   3 +
> >  target/mips/cpu.h                    |  28 ++
> >  target/mips/internal.h               |   2 +
> >  target/mips/kvm.c                    | 212 +++++++++
> >  target/mips/machine.c                |   6 +-
> >  target/mips/mips-defs.h              |   7 +-
> >  target/mips/translate.c              |   2 +
> >  target/mips/translate_init.inc.c     |  86 ++++
> >  18 files changed, 1300 insertions(+), 9 deletions(-)
> >  create mode 100644 hw/mips/common.c
> >  create mode 100644 hw/mips/mips_loongson3.c
> > --
> > 2.7.0



--
Huacai Chen