[PATCH] RISC-V: Add 'Smcntrpmf' extension and its CSRs

[Jan Beulich]

On 01.08.2023 06:51, Nelson Chu wrote:
> On Mon, Jul 24, 2023 at 1:25 PM Jiawei <jiawei@iscas.ac.cn> wrote:
> 
>> This patch supports RISC-V cycle and instret privilege mode filtering
>> extension(Smcntrpmf)[1]. It adds two new 64-bits register mcyclecfg
>> and minstretcfg that configure privilege mode filtering for the cycle
>> and instret counters, respectively. Remove dropped CSRs that use the
>> same CSR number with Smcntrpmf extension(mscounteren, mhcounteren).
>>
> 
> If we still want to support the privileged versions, then we should use
> DECLARE_CSR_ALIAS for these kinds of the reused csrs.  However, maybe it's
> time that we should give up on supporting the multiple privileged versions
> in binutils, and then support the newest one.

That might work now, but going forward you won't be able to always only
support the newest version, I suppose.

Jan