[PATCH 1/1] firmware: arm_scmi: Increase MAX_OPPS to 64

[PATCH 1/1] firmware: arm_scmi: Increase MAX_OPPS to 64

[Vivek Aknurwar]

Some upcoming SoCs define more than 32 operating performance points (OPPs),
exceeding the current SCMI protocol limit. Increase MAX_OPPS to 64
(next power of 2) to support these configurations.

Signed-off-by: Vivek Aknurwar <vivek.aknurwar@oss.qualcomm.com>
---
 drivers/firmware/arm_scmi/perf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c
index 683fd9b85c5c..2249ef7fe790 100644
--- a/drivers/firmware/arm_scmi/perf.c
+++ b/drivers/firmware/arm_scmi/perf.c
@@ -27,7 +27,7 @@
 /* Updated only after ALL the mandatory features for that version are merged */
 #define SCMI_PROTOCOL_SUPPORTED_VERSION		0x40000
 
-#define MAX_OPPS		32
+#define MAX_OPPS		64
 
 enum scmi_performance_protocol_cmd {
 	PERF_DOMAIN_ATTRIBUTES = 0x3,
-- 
2.34.1

Re: [PATCH 1/1] firmware: arm_scmi: Increase MAX_OPPS to 64

[Konrad Dybcio]

On 10/14/25 9:34 AM, Vivek Aknurwar wrote:
> Some upcoming SoCs define more than 32 operating performance points (OPPs),
> exceeding the current SCMI protocol limit. Increase MAX_OPPS to 64
> (next power of 2) to support these configurations.
> 
> Signed-off-by: Vivek Aknurwar <vivek.aknurwar@oss.qualcomm.com>
> ---

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>

Konrad

Re: [PATCH 1/1] firmware: arm_scmi: Increase MAX_OPPS to 64

[Vivek Aknurwar]

Hello Sudeep/Cristian,

Just following up on this patch. If there’s anything missing or
needs adjustment, please let me know.

Thanks,
Vivek
On 10/14/2025 12:34 AM, Vivek Aknurwar wrote:
> Some upcoming SoCs define more than 32 operating performance points (OPPs),
> exceeding the current SCMI protocol limit. Increase MAX_OPPS to 64
> (next power of 2) to support these configurations.
> 
> Signed-off-by: Vivek Aknurwar <vivek.aknurwar@oss.qualcomm.com>
> ---
>  drivers/firmware/arm_scmi/perf.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c
> index 683fd9b85c5c..2249ef7fe790 100644
> --- a/drivers/firmware/arm_scmi/perf.c
> +++ b/drivers/firmware/arm_scmi/perf.c
> @@ -27,7 +27,7 @@
>  /* Updated only after ALL the mandatory features for that version are merged */
>  #define SCMI_PROTOCOL_SUPPORTED_VERSION		0x40000
>  
> -#define MAX_OPPS		32
> +#define MAX_OPPS		64
>  
>  enum scmi_performance_protocol_cmd {
>  	PERF_DOMAIN_ATTRIBUTES = 0x3,

Re: [PATCH 1/1] firmware: arm_scmi: Increase MAX_OPPS to 64

[Sudeep Holla]

On Wed, Dec 10, 2025 at 03:28:37PM -0800, Vivek Aknurwar wrote:
> Hello Sudeep/Cristian,
> 
> Just following up on this patch. If there’s anything missing or
> needs adjustment, please let me know.
> 

Sorry seem to have slipped through the cracks while I was away. I will
queue it for next merge window soon.

-- 
Regards,
Sudeep

Re: [PATCH 1/1] firmware: arm_scmi: Increase MAX_OPPS to 64

[Alexey Klimov]

On Wed Dec 10, 2025 at 11:28 PM GMT, Vivek Aknurwar wrote:
> Hello Sudeep/Cristian,
>
> Just following up on this patch. If there’s anything missing or
> needs adjustment, please let me know.

Vivek, please avoid top-posting.

> On 10/14/2025 12:34 AM, Vivek Aknurwar wrote:
>> Some upcoming SoCs define more than 32 operating performance points (OPPs),
>> exceeding the current SCMI protocol limit. Increase MAX_OPPS to 64
>> (next power of 2) to support these configurations.

Didn't touch for a while. The way it is stated confuses me a bit.
Should the value defined by protocol be updated out of the blue?
Should the protocol (defined by spec) be changed first?

If protocol changes, then should the version/minor version be
updated/added?

Thanks,
Alexey


>> Signed-off-by: Vivek Aknurwar <vivek.aknurwar@oss.qualcomm.com>
>> ---
>>  drivers/firmware/arm_scmi/perf.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>> 
>> diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c
>> index 683fd9b85c5c..2249ef7fe790 100644
>> --- a/drivers/firmware/arm_scmi/perf.c
>> +++ b/drivers/firmware/arm_scmi/perf.c
>> @@ -27,7 +27,7 @@
>>  /* Updated only after ALL the mandatory features for that version are merged */
>>  #define SCMI_PROTOCOL_SUPPORTED_VERSION		0x40000
>>  
>> -#define MAX_OPPS		32
>> +#define MAX_OPPS		64
>>  
>>  enum scmi_performance_protocol_cmd {
>>  	PERF_DOMAIN_ATTRIBUTES = 0x3,

Re: [PATCH 1/1] firmware: arm_scmi: Increase MAX_OPPS to 64

[Sudeep Holla]

On Thu, Dec 11, 2025 at 01:14:06PM +0000, Alexey Klimov wrote:
> > On 10/14/2025 12:34 AM, Vivek Aknurwar wrote:
> >> Some upcoming SoCs define more than 32 operating performance points (OPPs),
> >> exceeding the current SCMI protocol limit. Increase MAX_OPPS to 64
> >> (next power of 2) to support these configurations.
> 
> Didn't touch for a while. The way it is stated confuses me a bit.
> Should the value defined by protocol be updated out of the blue?
> Should the protocol (defined by spec) be changed first?
> 

Ah good point on confusing commit message. I just assumed it is limitation
of the implementation. I can update the log when applying. It is not spec
or protocol limitation for sure.

How about this ?

  | firmware: arm_scmi: Increase performance MAX_OPPS limit to 64
  |
  | Some platforms expose more than 32 operating performance points (OPPs)
  | per performance domain via the SCMI performance protocol, but the
  | driver currently limits the number of OPPs it can handle to 32 via
  | MAX_OPPS.
  |
  | Bump MAX_OPPS to 64 so that these platforms can register all their
  | performance levels. This is an internal limit in the driver only and
  | does not affect the SCMI protocol ABI.
  |
  | 64 is chosen as the next power of two above the existing limit.


-- 
Regards,
Sudeep

Re: [PATCH 1/1] firmware: arm_scmi: Increase MAX_OPPS to 64

[Alexey Klimov]

On Thu Dec 11, 2025 at 1:48 PM GMT, Sudeep Holla wrote:
> On Thu, Dec 11, 2025 at 01:14:06PM +0000, Alexey Klimov wrote:
>> > On 10/14/2025 12:34 AM, Vivek Aknurwar wrote:
>> >> Some upcoming SoCs define more than 32 operating performance points (OPPs),
>> >> exceeding the current SCMI protocol limit. Increase MAX_OPPS to 64
>> >> (next power of 2) to support these configurations.
>> 
>> Didn't touch for a while. The way it is stated confuses me a bit.
>> Should the value defined by protocol be updated out of the blue?
>> Should the protocol (defined by spec) be changed first?
>> 
>
> Ah good point on confusing commit message. I just assumed it is limitation
> of the implementation. I can update the log when applying. It is not spec
> or protocol limitation for sure.
>
> How about this ?
>
>   | firmware: arm_scmi: Increase performance MAX_OPPS limit to 64
>   |
>   | Some platforms expose more than 32 operating performance points (OPPs)
>   | per performance domain via the SCMI performance protocol, but the
>   | driver currently limits the number of OPPs it can handle to 32 via
>   | MAX_OPPS.
>   |
>   | Bump MAX_OPPS to 64 so that these platforms can register all their
>   | performance levels. This is an internal limit in the driver only and
>   | does not affect the SCMI protocol ABI.
>   |
>   | 64 is chosen as the next power of two above the existing limit.

Yeah, that sounds better :)

I also thought that this was a driver limitation, not the protocol/spec one
as stated in the original patch.

I don't mind updating the commit message like this (but I am not the author
of the original patch).

Best regards,
Alexey

Re: [PATCH 1/1] firmware: arm_scmi: Increase MAX_OPPS to 64

[Sudeep Holla]

On Thu, Dec 11, 2025 at 01:54:01PM +0000, Alexey Klimov wrote:
> On Thu Dec 11, 2025 at 1:48 PM GMT, Sudeep Holla wrote:
> > On Thu, Dec 11, 2025 at 01:14:06PM +0000, Alexey Klimov wrote:
> >> > On 10/14/2025 12:34 AM, Vivek Aknurwar wrote:
> >> >> Some upcoming SoCs define more than 32 operating performance points (OPPs),
> >> >> exceeding the current SCMI protocol limit. Increase MAX_OPPS to 64
> >> >> (next power of 2) to support these configurations.
> >> 
> >> Didn't touch for a while. The way it is stated confuses me a bit.
> >> Should the value defined by protocol be updated out of the blue?
> >> Should the protocol (defined by spec) be changed first?
> >> 
> >
> > Ah good point on confusing commit message. I just assumed it is limitation
> > of the implementation. I can update the log when applying. It is not spec
> > or protocol limitation for sure.
> >
> > How about this ?
> >
> >   | firmware: arm_scmi: Increase performance MAX_OPPS limit to 64
> >   |
> >   | Some platforms expose more than 32 operating performance points (OPPs)
> >   | per performance domain via the SCMI performance protocol, but the
> >   | driver currently limits the number of OPPs it can handle to 32 via
> >   | MAX_OPPS.
> >   |
> >   | Bump MAX_OPPS to 64 so that these platforms can register all their
> >   | performance levels. This is an internal limit in the driver only and
> >   | does not affect the SCMI protocol ABI.
> >   |
> >   | 64 is chosen as the next power of two above the existing limit.
> 
> Yeah, that sounds better :)
> 

Thanks!

> I also thought that this was a driver limitation, not the protocol/spec one
> as stated in the original patch.
> 
> I don't mind updating the commit message like this (but I am not the author
> of the original patch).
> 

Vivek, are you happy with the above edited commit message ?

-- 
Regards,
Sudeep

Re: [PATCH 1/1] firmware: arm_scmi: Increase MAX_OPPS to 64

[Alexey Klimov]

On Thu Dec 11, 2025 at 2:07 PM GMT, Sudeep Holla wrote:

[..]

>> > Ah good point on confusing commit message. I just assumed it is limitation
>> > of the implementation. I can update the log when applying. It is not spec
>> > or protocol limitation for sure.
>> >
>> > How about this ?
>> >
>> >   | firmware: arm_scmi: Increase performance MAX_OPPS limit to 64
>> >   |
>> >   | Some platforms expose more than 32 operating performance points (OPPs)
>> >   | per performance domain via the SCMI performance protocol, but the
>> >   | driver currently limits the number of OPPs it can handle to 32 via
>> >   | MAX_OPPS.
>> >   |
>> >   | Bump MAX_OPPS to 64 so that these platforms can register all their
>> >   | performance levels. This is an internal limit in the driver only and
>> >   | does not affect the SCMI protocol ABI.
>> >   |
>> >   | 64 is chosen as the next power of two above the existing limit.
>> 
>> Yeah, that sounds better :)
>> 
> Thanks!
>
>> I also thought that this was a driver limitation, not the protocol/spec one
>> as stated in the original patch.
>> 
>> I don't mind updating the commit message like this (but I am not the author
>> of the original patch).
>> 
> Vivek, are you happy with the above edited commit message ?

FWIW, with updated commit message feel free to use:

Reviewed-by: Alexey Klimov <alexey.klimov@linaro.org>

Best regards,
Alexey

Re: [PATCH 1/1] firmware: arm_scmi: Increase MAX_OPPS to 64

[Vivek Aknurwar]

On 12/11/2025 6:25 AM, Alexey Klimov wrote:
> On Thu Dec 11, 2025 at 2:07 PM GMT, Sudeep Holla wrote:
> 
> [..]
> 
>>>> Ah good point on confusing commit message. I just assumed it is limitation
>>>> of the implementation. I can update the log when applying. It is not spec
>>>> or protocol limitation for sure.
>>>>
>>>> How about this ?
>>>>
>>>>   | firmware: arm_scmi: Increase performance MAX_OPPS limit to 64
>>>>   |
>>>>   | Some platforms expose more than 32 operating performance points (OPPs)
>>>>   | per performance domain via the SCMI performance protocol, but the
>>>>   | driver currently limits the number of OPPs it can handle to 32 via
>>>>   | MAX_OPPS.
>>>>   |
>>>>   | Bump MAX_OPPS to 64 so that these platforms can register all their
>>>>   | performance levels. This is an internal limit in the driver only and
>>>>   | does not affect the SCMI protocol ABI.
>>>>   |
>>>>   | 64 is chosen as the next power of two above the existing limit.
>>>
>>> Yeah, that sounds better :)
>>>
>> Thanks!
>>
>>> I also thought that this was a driver limitation, not the protocol/spec one
>>> as stated in the original patch.
>>>
>>> I don't mind updating the commit message like this (but I am not the author
>>> of the original patch).
>>>
>> Vivek, are you happy with the above edited commit message ?

Yes, I’m good with the suggested commit message. Thanks for clarifying!

Signed-off-by: Vivek Aknurwar <vivek.aknurwar@oss.qualcomm.com>
> 
> FWIW, with updated commit message feel free to use:
> 
> Reviewed-by: Alexey Klimov <alexey.klimov@linaro.org>
> 
> Best regards,
> Alexey

Re: [PATCH 1/1] firmware: arm_scmi: Increase MAX_OPPS to 64

[Sudeep Holla]

On Tue, 14 Oct 2025 00:34:54 -0700, Vivek Aknurwar wrote:
> Some upcoming SoCs define more than 32 operating performance points (OPPs),
> exceeding the current SCMI protocol limit. Increase MAX_OPPS to 64
> (next power of 2) to support these configurations.
> 

Applied to sudeep.holla/linux (for-next/scmi/updates), thanks!

[1/1] firmware: arm_scmi: Increase MAX_OPPS to 64
      https://git.kernel.org/sudeep.holla/c/6c2fd7a71e7a
--
Regards,
Sudeep