Loongson Binary Translation (LBT) is used to accelerate binary
translation. LBT feature is added in kvm mode, not supported in TCG
mode since it is not emulated.

Here lbt=on/off property is added to parse command line to
enable/disable lbt feature. Also fix registers relative lbt are saved
and restored during migration.

---
v3 ... v4:
  1. Verify and enable LBT feature in function kvm_arch_init_vcpu()
     rather than loongarch_cpu_post_init(), since LBT feature is only
     effective in kvm mode and function kvm_feature_supported() can be
     defined as static.
  2. Define structure elment ftop in structure LoongArchBT as uint32_t
     to keep consist with kernel and real HW.

v2 ... v3:
  1. Property lbt is added only if kvm is enabled
  2. Use feature variable lbt with OnOffAuto type, rather than feature
     bitmap flags default_features and forced_features

v1 ... v2:
  1. Add LBT register saving and restoring in vmstate
  2. Add two pseudo feature flags: default_features and forced_features
---
Bibo Mao (2):
  target/loongarch: Add loongson binary translation feature
  target/loongarch: Implement lbt registers save/restore function

 target/loongarch/cpu.c                |  24 ++++++
 target/loongarch/cpu.h                |  18 ++++
 target/loongarch/kvm/kvm.c            | 117 +++++++++++++++++++++++++-
 target/loongarch/loongarch-qmp-cmds.c |   2 +-
 target/loongarch/machine.c            |  24 ++++++
 5 files changed, 183 insertions(+), 2 deletions(-)


base-commit: e638d685ec2a0700fb9529cbd1b2823ac4120c53
-- 
2.39.3