| Message ID | 20230409181918.29270-2-quic_nkela@quicinc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Allow parameter in smc/hvc calls | expand |
On 09/04/2023 20:19, Nikunj Kela wrote: > Currently, smc/hvc calls are made with smc-id only. The parameters are > all set to zeros. This patch defines two optional device tree bindings, > that can be used to pass parameters in smc/hvc calls. > > This is useful when multiple scmi instances are used with common smc-id. > > Signed-off-by: Nikunj Kela <quic_nkela@quicinc.com> > --- > .../devicetree/bindings/firmware/arm,scmi.yaml | 16 ++++++++++++++++ > 1 file changed, 16 insertions(+) > > diff --git a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml > index 5824c43e9893..08c331a79b80 100644 > --- a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml > +++ b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml > @@ -115,6 +115,22 @@ properties: > description: > SMC id required when using smc or hvc transports > > + arm,smc32-params: > + $ref: /schemas/types.yaml#/definitions/uint32-array > + description: > + An optional parameter list passed in smc32 or hvc32 calls > + default: 0 > + minItems: 1 > + maxItems: 6 > + > + arm,smc64-params: > + $ref: /schemas/types.yaml#/definitions/uint64-array > + description: > + An optional parameter list passed in smc64 or hvc64 calls > + default: 0 > + minItems: 1 > + maxItems: 6 These do not look like hardware properties and the fact that you need two properties for the same also points that you tied it to specific SW interface. Why this should be board-specific? Actually better question - why this should be fixed per board? Doesn't my software want to have different parameters, depending on some other condition? You also did not provide any DTS user for this, so difficult to judge usefulness. Best regards, Krzysztof
On 4/10/2023 10:20 AM, Krzysztof Kozlowski wrote: > On 09/04/2023 20:19, Nikunj Kela wrote: >> Currently, smc/hvc calls are made with smc-id only. The parameters are >> all set to zeros. This patch defines two optional device tree bindings, >> that can be used to pass parameters in smc/hvc calls. >> >> This is useful when multiple scmi instances are used with common smc-id. >> >> Signed-off-by: Nikunj Kela <quic_nkela@quicinc.com> >> --- >> .../devicetree/bindings/firmware/arm,scmi.yaml | 16 ++++++++++++++++ >> 1 file changed, 16 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml >> index 5824c43e9893..08c331a79b80 100644 >> --- a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml >> +++ b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml >> @@ -115,6 +115,22 @@ properties: >> description: >> SMC id required when using smc or hvc transports >> >> + arm,smc32-params: >> + $ref: /schemas/types.yaml#/definitions/uint32-array >> + description: >> + An optional parameter list passed in smc32 or hvc32 calls >> + default: 0 >> + minItems: 1 >> + maxItems: 6 >> + >> + arm,smc64-params: >> + $ref: /schemas/types.yaml#/definitions/uint64-array >> + description: >> + An optional parameter list passed in smc64 or hvc64 calls >> + default: 0 >> + minItems: 1 >> + maxItems: 6 > These do not look like hardware properties and the fact that you need > two properties for the same also points that you tied it to specific SW > interface. This is certainly not the H/W property but then smc-id is also not H/W property either but that gets passed via DTB. I could use the same property for both however I wasn't sure which datatype should be used, uint32-array/uint64-array. Moreover, I thought if users are passing parameters, they better know which SMC convention they are using hence used two explicit properties. > Why this should be board-specific? Actually better question - why this > should be fixed per board? Doesn't my software want to have different > parameters, depending on some other condition? Not sure I follow, I didn't say this is board specific. People can use the parameters to pass whatever their S/W demands. SMC/HVC calls are made by passing parameters which is what this patch is enabling. > > You also did not provide any DTS user for this, so difficult to judge > usefulness. The work is still on going and we will push the dts in few months, however that shouldn't stop making changes in advance. > Best regards, > Krzysztof >
On 10/04/2023 19:33, Nikunj Kela wrote: > > On 4/10/2023 10:20 AM, Krzysztof Kozlowski wrote: >> On 09/04/2023 20:19, Nikunj Kela wrote: >>> Currently, smc/hvc calls are made with smc-id only. The parameters are >>> all set to zeros. This patch defines two optional device tree bindings, >>> that can be used to pass parameters in smc/hvc calls. >>> >>> This is useful when multiple scmi instances are used with common smc-id. >>> >>> Signed-off-by: Nikunj Kela <quic_nkela@quicinc.com> >>> --- >>> .../devicetree/bindings/firmware/arm,scmi.yaml | 16 ++++++++++++++++ >>> 1 file changed, 16 insertions(+) >>> >>> diff --git a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml >>> index 5824c43e9893..08c331a79b80 100644 >>> --- a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml >>> +++ b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml >>> @@ -115,6 +115,22 @@ properties: >>> description: >>> SMC id required when using smc or hvc transports >>> >>> + arm,smc32-params: >>> + $ref: /schemas/types.yaml#/definitions/uint32-array >>> + description: >>> + An optional parameter list passed in smc32 or hvc32 calls >>> + default: 0 >>> + minItems: 1 >>> + maxItems: 6 >>> + >>> + arm,smc64-params: >>> + $ref: /schemas/types.yaml#/definitions/uint64-array >>> + description: >>> + An optional parameter list passed in smc64 or hvc64 calls >>> + default: 0 >>> + minItems: 1 >>> + maxItems: 6 >> These do not look like hardware properties and the fact that you need >> two properties for the same also points that you tied it to specific SW >> interface. > > This is certainly not the H/W property but then smc-id is also not H/W > property either Yep, maybe it should be also removed? > > but that gets passed via DTB. I could use the same property for both > however I wasn't sure > > which datatype should be used, uint32-array/uint64-array. Moreover, I > thought if users are > > passing parameters, they better know which SMC convention they are using > hence used two > > explicit properties. Does not solve my concern. > >> Why this should be board-specific? Actually better question - why this >> should be fixed per board? Doesn't my software want to have different >> parameters, depending on some other condition? > > Not sure I follow, I didn't say this is board specific. But putting it in DTS which is customized per board is then board specific. > People can use > the parameters to pass > > whatever their S/W demands. SMC/HVC calls are made by passing parameters > which is what this patch is enabling. I cannot follow your paragraphs. You cut middle of sentence. Anyway, if this is to match whatever their SW demands, it is not Devicetree property. > >> >> You also did not provide any DTS user for this, so difficult to judge >> usefulness. > > The work is still on going and we will push the dts in few months, > however that shouldn't stop > > making changes in advance. With a proper DTS maybe it would be easier to convince us why SW interface should be put to Devicetree... but sure, we can skip DTS and answer is - this looks like SW property and not a DT. Best regards, Krzysztof
diff --git a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml index 5824c43e9893..08c331a79b80 100644 --- a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml +++ b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml @@ -115,6 +115,22 @@ properties: description: SMC id required when using smc or hvc transports + arm,smc32-params: + $ref: /schemas/types.yaml#/definitions/uint32-array + description: + An optional parameter list passed in smc32 or hvc32 calls + default: 0 + minItems: 1 + maxItems: 6 + + arm,smc64-params: + $ref: /schemas/types.yaml#/definitions/uint64-array + description: + An optional parameter list passed in smc64 or hvc64 calls + default: 0 + minItems: 1 + maxItems: 6 + linaro,optee-channel-id: $ref: /schemas/types.yaml#/definitions/uint32 description:
Currently, smc/hvc calls are made with smc-id only. The parameters are all set to zeros. This patch defines two optional device tree bindings, that can be used to pass parameters in smc/hvc calls. This is useful when multiple scmi instances are used with common smc-id. Signed-off-by: Nikunj Kela <quic_nkela@quicinc.com> --- .../devicetree/bindings/firmware/arm,scmi.yaml | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)