In this patch set, we process the pc reigsters writes,
gdb reads and writes, and address calculation under
different UXLEN settings.

The patch set v6 has been tested by running rv64 Linux with 
rv32 rootfs in compat mode. You can almost follow the test [1]
given by GuoRen, except using the branch riscv-upstream-uxl-v6
on my QEMU repo [2].

[1] https://lore.kernel.org/linux-arm-kernel/20211228143958.3409187-17-guoren@kernel.org/t/
[2] https://github.com/romanheros/qemu.git 

Patch 3, 5, 20, 22, have not been reviewed. Others have been reviewed or acked.

v6:
  Pass boot 32bit rootfs on compat Linux
  Pass test cases on compat OpenTee
  Fix csr write mask 
  Fix WARL for uxl
  Fix sstatus read for uxl
  Relax UXL field for debugging
  Don't bump machine state version for xl
  Rename cpu_get_xl to cpu_recompute_xl
  Rebase to vector v1.0
  Rebase to 128 bit cpu

v5:
  Add xl field in env to clear up redundant riscv_cpu_xl
  Adjust pmpcfg access with mxl
  Select gdb core xml according to mxl 

v4:
  Support SSTATUS64_UXL write
  Bump vmstate version for vill split

v3:
  Merge gen_pm_adjust_address into a canonical address function
  Adjust address for RVA with XLEN
  Split pm_enabled into pm_mask_enabled and pm_base_enabled
  Replace array of pm tcg globals with one scalar tcg global
  Split and change patch sequence

v2:
  Split out vill from vtype
  Remove context switch when xlen changes at exception
  Use XL instead of OL in many places
  Use pointer masking and XLEN for vector address
  Define an common fuction to calculate address for ld


LIU Zhiwei (22):
  target/riscv: Adjust pmpcfg access with mxl
  target/riscv: Don't save pc when exception return
  target/riscv: Sign extend link reg for jal and jalr
  target/riscv: Sign extend pc for different XLEN
  target/riscv: Create xl field in env
  target/riscv: Ignore the pc bits above XLEN
  target/riscv: Extend pc for runtime pc write
  target/riscv: Use gdb xml according to max mxlen
  target/riscv: Relax debug check for pm write
  target/riscv: Adjust csr write mask with XLEN
  target/riscv: Create current pm fields in env
  target/riscv: Alloc tcg global for cur_pm[mask|base]
  target/riscv: Calculate address according to XLEN
  target/riscv: Split pm_enabled into mask and base
  target/riscv: Split out the vill from vtype
  target/riscv: Adjust vsetvl according to XLEN
  target/riscv: Remove VILL field in VTYPE
  target/riscv: Fix check range for first fault only
  target/riscv: Adjust vector address with mask
  target/riscv: Adjust scalar reg in vector with XLEN
  target/riscv: Enable uxl field write
  target/riscv: Relax UXL field for debugging

 target/riscv/cpu.c                            | 32 +++++--
 target/riscv/cpu.h                            | 45 ++++++++-
 target/riscv/cpu_helper.c                     | 94 +++++++++----------
 target/riscv/csr.c                            | 74 +++++++++++++--
 target/riscv/gdbstub.c                        | 71 ++++++++++----
 target/riscv/helper.h                         |  4 +-
 .../riscv/insn_trans/trans_privileged.c.inc   |  9 +-
 target/riscv/insn_trans/trans_rva.c.inc       |  9 +-
 target/riscv/insn_trans/trans_rvd.c.inc       | 19 +---
 target/riscv/insn_trans/trans_rvf.c.inc       | 19 +---
 target/riscv/insn_trans/trans_rvi.c.inc       | 39 +++-----
 target/riscv/insn_trans/trans_rvv.c.inc       |  6 +-
 target/riscv/machine.c                        | 16 +++-
 target/riscv/op_helper.c                      |  7 +-
 target/riscv/pmp.c                            | 12 +--
 target/riscv/translate.c                      | 90 +++++++++---------
 target/riscv/vector_helper.c                  | 39 +++++---
 17 files changed, 355 insertions(+), 230 deletions(-)

-- 
2.25.1