Re: [PATCH v2 3/3] riscv: dts: sophgo: add zfh for sg2042

Chen Wang
2025-05-31T02:50:09Z

On 2025/5/31 9:34, Inochi Amaoto wrote:
> On Tue, May 27, 2025 at 06:22:05PM +0800, Chen Wang wrote:
>> On 2025/5/27 17:34, Han Gao wrote:
>>> On Thu, May 15, 2025 at 9:33 AM Chen Wang <unicorn_wang@outlook.com> wrote:
>>>> On 2025/5/14 23:15, Han Gao wrote:
>>>>> sg2042 support Zfh ISA extension [1].
>>>>>
>>>>> Link: https://occ-oss-prod.oss-cn-hangzhou.aliyuncs.com/resource//1737721869472/%E7%8E%84%E9%93%81C910%E4%B8%8EC920R1S6%E7%94%A8%E6%88%B7%E6%89%8B%E5%86%8C%28xrvm%29_20250124.pdf [1]
>>>>>
>>>>> Signed-off-by: Han Gao <rabenda.cn@gmail.com>
>>>>> ---
>>>>> arch/riscv/boot/dts/sophgo/sg2042-cpus.dtsi | 256 ++++++++++----------
>>>>> 1 file changed, 128 insertions(+), 128 deletions(-)
>>>>>
>>>>> diff --git a/arch/riscv/boot/dts/sophgo/sg2042-cpus.dtsi b/arch/riscv/boot/dts/sophgo/sg2042-cpus.dtsi
>>>>> index f483f62ab0c4..8dd1a3c60bc4 100644
>>>>> --- a/arch/riscv/boot/dts/sophgo/sg2042-cpus.dtsi
>>>>> +++ b/arch/riscv/boot/dts/sophgo/sg2042-cpus.dtsi
>>>>> @@ -256,11 +256,11 @@ core3 {
>>>>> cpu0: cpu@0 {
>>>>> compatible = "thead,c920", "riscv";
>>>>> device_type = "cpu";
>>>>> - riscv,isa = "rv64imafdc";
>>>>> + riscv,isa = "rv64imafdc_zfh";
>>>> Need not touch this. "riscv,isa" is deprecated and replaced by
>>>> "riscv,isa-base" & "riscv,isa-extensions".
>>>>
>>>> And only adding zfh for this looks a bit werid.
>>>>
>>>> Actually, I plan to remove "riscv,isa" later, so please don't touch this
>>>> from now on.
>>> I think that since the linux kernel is the upstream for devicetree, it
>>> cannot yet remove riscv, isa needs to maintain compatibility.
>> OK, maybe it's not good to remove "riscv,isa".
>>
>> Can this patch not modify "riscv,isa", but only add something for
>> "riscv,isa-extensions"?
>>
> I can remove this while merging the patch, is it OK for you?
>
> Regards,
> Inochi

@Inochi,

Han does not want to remove this "riscv,isa"，he said some other
components, such as u-boot may have dependency on this.

@Han, please provide more info if needed.

Thanks,

Chen