[PATCH v1 00/24] Add KVM LoongArch support

From: Tianrui Zhao
Date: Mon Feb 13 2023 - 21:57:12 EST

This series adds KVM LoongArch support. Loongson 3A5000 supports hardware
assisted virtualization. With cpu virtualization, there are separate
hw-supported user mode and kernel mode in guest mode. With memory
virtualization, there are two-level hw mmu table for guest mode and host
mode. Also there is separate hw cpu timer with consant frequency in
guest mode, so that vm can migrate between hosts with different freq.
Currently, we are able to boot LoongArch Linux Guests.

Few key aspects of KVM LoongArch added by this series are:
1. Enable kvm hardware function when kvm module is loaded.
2. Implement VM and vcpu related ioctl interface such as vcpu create,
vcpu run etc. GET_ONE_REG/SET_ONE_REG ioctl commands are use to
get general registers one by one; KVM_GET_CSRS can be used to
get system registers with batch mode similar with KVM_GET_MSRS in x86.
3. Hardware access about MMU, timer and csr are emulated in kernel.
4. Hardwares such as mmio and iocsr device are emulated in user space
such as APIC, IPI, pci devices etc.

The running environment of LoongArch virt machine:
1. Cross tools to build kernel and uefi:
$ wget https://github.com/loongson/build-tools/releases/download/2022.09.06/loongarch64-clfs-6.3-cross-tools-gcc-glibc.tar.xz
tar -vxf loongarch64-clfs-6.3-cross-tools-gcc-glibc.tar.xz -C /opt
export PATH=/opt/cross-tools/bin:$PATH
export LD_LIBRARY_PATH=/opt/cross-tools/lib:$LD_LIBRARY_PATH
export LD_LIBRARY_PATH=/opt/cross-tools/loongarch64-unknown-linux-gnu/lib/:$LD_LIBRARY_PATH
2. This series is based on the linux source code:
https://github.com/loongson/linux-loongarch-kvm
Build command:
git checkout kvm-loongarch
make ARCH=loongarch CROSS_COMPILE=loongarch64-unknown-linux-gnu- loongson3_defconfig
make ARCH=loongarch CROSS_COMPILE=loongarch64-unknown-linux-gnu-
3. QEMU hypervisor with LoongArch supported:
https://github.com/loongson/qemu
Build command:
git checkout kvm-loongarch
./configure --target-list="loongarch64-softmmu" --enable-kvm
make
4. Uefi bios of LoongArch virt machine:
Reference: https://github.com/tianocore/edk2-platforms/tree/master/Platform/Loongson/LoongArchQemuPkg#readme
5. you can also access the binary files we have already build:
https://github.com/yangxiaojuan-loongson/qemu-binary

The command to boot loongarch virt machine:
$ qemu-system-loongarch64 -machine virt -m 4G -cpu la464 \
-smp 1 -bios QEMU_EFI.fd -kernel vmlinuz.efi -initrd ramdisk \
-serial stdio -monitor telnet:localhost:4495,server,nowait \
-append "root=/dev/ram rdinit=/sbin/init console=ttyS0,115200" \
--nographic


Tianrui Zhao (24):
LoongArch: KVM: Implement kvm module related interface
LoongArch: KVM: Implement VM related functions
LoongArch: KVM: Implement vcpu create,run,destroy operations.
LoongArch: KVM: Implement vcpu get, vcpu set registers
LoongArch: KVM: Implement vcpu ENABLE_CAP, CHECK_EXTENSION ioctl
interface
LoongArch: KVM: Implement fpu related operations for vcpu
LoongArch: KVM: Implement vcpu interrupt operations
LoongArch: KVM: Implement misc vcpu related interfaces
LoongArch: KVM: Implement vcpu load and vcpu put operations
LoongArch: KVM: Implement vcpu status description
LoongArch: KVM: Implement update VM id function
LoongArch: KVM: Implement virtual machine tlb operations
LoongArch: KVM: Implement vcpu timer operations
LoongArch: KVM: Implement kvm mmu operations
LoongArch: KVM: Implement handle csr excption
LoongArch: KVM: Implement handle iocsr exception
LoongArch: KVM: Implement handle idle exception
LoongArch: KVM: Implement handle gspr exception
LoongArch: KVM: Implement handle mmio exception
LoongArch: KVM: Implement handle fpu exception
LoongArch: KVM: Implement kvm exception vector
LoongArch: KVM: Implement vcpu world switch
LoongArch: KVM: Implement probe virtualization when loongarch cpu init
LoongArch: KVM: Enable kvm config and add the makefile

arch/loongarch/Kbuild | 1 +
arch/loongarch/Kconfig | 2 +
arch/loongarch/configs/loongson3_defconfig | 2 +
arch/loongarch/include/asm/cpu-features.h | 22 +
arch/loongarch/include/asm/cpu-info.h | 13 +
arch/loongarch/include/asm/inst.h | 16 +
arch/loongarch/include/asm/kvm_csr.h | 89 ++
arch/loongarch/include/asm/kvm_host.h | 257 +++++
arch/loongarch/include/asm/kvm_types.h | 11 +
arch/loongarch/include/asm/kvm_vcpu.h | 112 ++
arch/loongarch/include/asm/loongarch.h | 195 +++-
arch/loongarch/include/uapi/asm/kvm.h | 121 ++
arch/loongarch/kernel/asm-offsets.c | 32 +
arch/loongarch/kernel/cpu-probe.c | 53 +
arch/loongarch/kvm/Kconfig | 38 +
arch/loongarch/kvm/Makefile | 21 +
arch/loongarch/kvm/exit.c | 702 ++++++++++++
arch/loongarch/kvm/interrupt.c | 126 +++
arch/loongarch/kvm/main.c | 152 +++
arch/loongarch/kvm/mmu.c | 821 ++++++++++++++
arch/loongarch/kvm/switch.S | 327 ++++++
arch/loongarch/kvm/timer.c | 266 +++++
arch/loongarch/kvm/tlb.c | 31 +
arch/loongarch/kvm/trace.h | 137 +++
arch/loongarch/kvm/vcpu.c | 1185 ++++++++++++++++++++
arch/loongarch/kvm/vm.c | 85 ++
arch/loongarch/kvm/vmid.c | 64 ++
include/uapi/linux/kvm.h | 15 +
28 files changed, 4890 insertions(+), 6 deletions(-)
create mode 100644 arch/loongarch/include/asm/kvm_csr.h
create mode 100644 arch/loongarch/include/asm/kvm_host.h
create mode 100644 arch/loongarch/include/asm/kvm_types.h
create mode 100644 arch/loongarch/include/asm/kvm_vcpu.h
create mode 100644 arch/loongarch/include/uapi/asm/kvm.h
create mode 100644 arch/loongarch/kvm/Kconfig
create mode 100644 arch/loongarch/kvm/Makefile
create mode 100644 arch/loongarch/kvm/exit.c
create mode 100644 arch/loongarch/kvm/interrupt.c
create mode 100644 arch/loongarch/kvm/main.c
create mode 100644 arch/loongarch/kvm/mmu.c
create mode 100644 arch/loongarch/kvm/switch.S
create mode 100644 arch/loongarch/kvm/timer.c
create mode 100644 arch/loongarch/kvm/tlb.c
create mode 100644 arch/loongarch/kvm/trace.h
create mode 100644 arch/loongarch/kvm/vcpu.c
create mode 100644 arch/loongarch/kvm/vm.c
create mode 100644 arch/loongarch/kvm/vmid.c

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2.31.1