On 2023/3/28 11:18, Richard Henderson wrote:
> On 3/27/23 19:48, liweiwei wrote:
>>
>> On 2023/3/28 10:20, LIU Zhiwei wrote:
>>>
>>> On 2023/3/27 18:00, Weiwei Li wrote:
>>>> Since pointer mask works on effective address, and the xl works on the
>>>> generation of effective address, so xl related calculation should 
>>>> be done
>>>> before pointer mask.
>>>
>>> Incorrect. It has been done.
>>>
>>> When updating the pm_mask,  we have already considered the env->xl.
>>>
>>> You can see it in riscv_cpu_update_mask
>>>
>>>     if (env->xl == MXL_RV32) {
>>>         env->cur_pmmask = mask & UINT32_MAX;
>>>         env->cur_pmbase = base & UINT32_MAX;
>>>     } else {
>>>         env->cur_pmmask = mask;
>>>         env->cur_pmbase = base;
>>>     }
>>>
>> Yeah, I missed this part. Then we should ensure cur_pmmask/base is 
>> updated when xl changes.
>
> Is that even possible?  XL can change on priv level changes (SXL, UXL).

Yeah. Not possible, since only UXL is changable currently, and SXL/UXL 
can only be changed in higher priv level.

So the recompute for xl in write_mstatus() seems redundant.

Maybe there is a way to change current xl in future if misa.mxl is 
changable.

Regards,

Weiwei Li

>
>
> r~