[PATCH] dt-bindings: rtc: zynqmp: Describe power-domains property

Michal Simek posted 1 patch 1 year, 11 months ago
Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml | 3 +++
1 file changed, 3 insertions(+)
[PATCH] dt-bindings: rtc: zynqmp: Describe power-domains property
Posted by Michal Simek 1 year, 11 months ago
RTC has its own power domain on Xilinx Versal SOC that's why describe it as
optional property.

Signed-off-by: Michal Simek <michal.simek@amd.com>
---

 Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml b/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml
index d1f5eb996dba..838c3ce494de 100644
--- a/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml
+++ b/Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml
@@ -48,6 +48,9 @@ properties:
     default: 0x198233
     deprecated: true
 
+  power-domains:
+    maxItems: 1
+
 required:
   - compatible
   - reg
-- 
2.36.1
Re: [PATCH] dt-bindings: rtc: zynqmp: Describe power-domains property
Posted by Krzysztof Kozlowski 1 year, 11 months ago
On 16/02/2024 09:51, Michal Simek wrote:
> RTC has its own power domain on Xilinx Versal SOC that's why describe it as
> optional property.
> 
> Signed-off-by: Michal Simek <michal.simek@amd.com>
> ---
> 
>  Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml | 3 +++
>  1 file changed, 3 insertions(+)
> 

But Versal is not described in this binding, is it? I see only one
compatible.

Best regards,
Krzysztof
Re: [PATCH] dt-bindings: rtc: zynqmp: Describe power-domains property
Posted by Michal Simek 1 year, 11 months ago

On 2/16/24 10:19, Krzysztof Kozlowski wrote:
> On 16/02/2024 09:51, Michal Simek wrote:
>> RTC has its own power domain on Xilinx Versal SOC that's why describe it as
>> optional property.
>>
>> Signed-off-by: Michal Simek <michal.simek@amd.com>
>> ---
>>
>>   Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml | 3 +++
>>   1 file changed, 3 insertions(+)
>>
> 
> But Versal is not described in this binding, is it? I see only one
> compatible.

It is the same IP only as is on zynqmp with own power rail.

Pretty much with different firmware interface on zynqmp you can describe it too 
(and doesn't really matter if it is separated in HW or common for more IPs).

Thanks,
Michal
Re: [PATCH] dt-bindings: rtc: zynqmp: Describe power-domains property
Posted by Krzysztof Kozlowski 1 year, 11 months ago
On 16/02/2024 10:42, Michal Simek wrote:
> 
> 
> On 2/16/24 10:19, Krzysztof Kozlowski wrote:
>> On 16/02/2024 09:51, Michal Simek wrote:
>>> RTC has its own power domain on Xilinx Versal SOC that's why describe it as
>>> optional property.
>>>
>>> Signed-off-by: Michal Simek <michal.simek@amd.com>
>>> ---
>>>
>>>   Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml | 3 +++
>>>   1 file changed, 3 insertions(+)
>>>
>>
>> But Versal is not described in this binding, is it? I see only one
>> compatible.
> 
> It is the same IP only as is on zynqmp with own power rail.

Then you should have separate compatible, because they are not
identical. It would also allow you to narrow the domains to versal and
also require it (on versal).

Best regards,
Krzysztof
Re: [PATCH] dt-bindings: rtc: zynqmp: Describe power-domains property
Posted by Michal Simek 1 year, 11 months ago

On 2/17/24 09:26, Krzysztof Kozlowski wrote:
> On 16/02/2024 10:42, Michal Simek wrote:
>>
>>
>> On 2/16/24 10:19, Krzysztof Kozlowski wrote:
>>> On 16/02/2024 09:51, Michal Simek wrote:
>>>> RTC has its own power domain on Xilinx Versal SOC that's why describe it as
>>>> optional property.
>>>>
>>>> Signed-off-by: Michal Simek <michal.simek@amd.com>
>>>> ---
>>>>
>>>>    Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml | 3 +++
>>>>    1 file changed, 3 insertions(+)
>>>>
>>>
>>> But Versal is not described in this binding, is it? I see only one
>>> compatible.
>>
>> It is the same IP only as is on zynqmp with own power rail.
> 
> Then you should have separate compatible, because they are not
> identical. It would also allow you to narrow the domains to versal and
> also require it (on versal).

I can double check with HW guys but I am quite sure IP itself is exactly the 
same. What it is different is that there is own power domain to it (not shared 
one as is in zynqmp case).

Also Linux is non secure sw and if secure firmware won't allow to change setting 
of it it can't be required. I am just saying that Linux doesn't need to be owner 
of any power domain that's why it shouldn't be required property.

Thanks,
Michal
Re: [PATCH] dt-bindings: rtc: zynqmp: Describe power-domains property
Posted by Alexandre Belloni 1 year, 11 months ago
On 19/02/2024 14:11:50+0100, Michal Simek wrote:
> 
> 
> On 2/17/24 09:26, Krzysztof Kozlowski wrote:
> > On 16/02/2024 10:42, Michal Simek wrote:
> > > 
> > > 
> > > On 2/16/24 10:19, Krzysztof Kozlowski wrote:
> > > > On 16/02/2024 09:51, Michal Simek wrote:
> > > > > RTC has its own power domain on Xilinx Versal SOC that's why describe it as
> > > > > optional property.
> > > > > 
> > > > > Signed-off-by: Michal Simek <michal.simek@amd.com>
> > > > > ---
> > > > > 
> > > > >    Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml | 3 +++
> > > > >    1 file changed, 3 insertions(+)
> > > > > 
> > > > 
> > > > But Versal is not described in this binding, is it? I see only one
> > > > compatible.
> > > 
> > > It is the same IP only as is on zynqmp with own power rail.
> > 
> > Then you should have separate compatible, because they are not
> > identical. It would also allow you to narrow the domains to versal and
> > also require it (on versal).
> 
> I can double check with HW guys but I am quite sure IP itself is exactly the
> same. What it is different is that there is own power domain to it (not
> shared one as is in zynqmp case).
> 
> Also Linux is non secure sw and if secure firmware won't allow to change
> setting of it it can't be required. I am just saying that Linux doesn't need
> to be owner of any power domain that's why it shouldn't be required
> property.

I guess because the integration is different, you still need a
differente compatible so you can forbid the property on non-Versal.

> 
> Thanks,
> Michal

-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
Re: [PATCH] dt-bindings: rtc: zynqmp: Describe power-domains property
Posted by Krzysztof Kozlowski 1 year, 11 months ago
On 19/02/2024 14:11, Michal Simek wrote:
> 
> 
> On 2/17/24 09:26, Krzysztof Kozlowski wrote:
>> On 16/02/2024 10:42, Michal Simek wrote:
>>>
>>>
>>> On 2/16/24 10:19, Krzysztof Kozlowski wrote:
>>>> On 16/02/2024 09:51, Michal Simek wrote:
>>>>> RTC has its own power domain on Xilinx Versal SOC that's why describe it as
>>>>> optional property.
>>>>>
>>>>> Signed-off-by: Michal Simek <michal.simek@amd.com>
>>>>> ---
>>>>>
>>>>>    Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml | 3 +++
>>>>>    1 file changed, 3 insertions(+)
>>>>>
>>>>
>>>> But Versal is not described in this binding, is it? I see only one
>>>> compatible.
>>>
>>> It is the same IP only as is on zynqmp with own power rail.
>>
>> Then you should have separate compatible, because they are not
>> identical. It would also allow you to narrow the domains to versal and
>> also require it (on versal).
> 
> I can double check with HW guys but I am quite sure IP itself is exactly the 
> same. What it is different is that there is own power domain to it (not shared 
> one as is in zynqmp case).

What does it mean shared one? If several devices share power domain,
then they all should have power-domains property.

> 
> Also Linux is non secure sw and if secure firmware won't allow to change setting 
> of it it can't be required. I am just saying that Linux doesn't need to be owner 
> of any power domain that's why it shouldn't be required property.


Best regards,
Krzysztof
Re: [PATCH] dt-bindings: rtc: zynqmp: Describe power-domains property
Posted by Michal Simek 1 year, 11 months ago

On 2/19/24 14:19, Krzysztof Kozlowski wrote:
> On 19/02/2024 14:11, Michal Simek wrote:
>>
>>
>> On 2/17/24 09:26, Krzysztof Kozlowski wrote:
>>> On 16/02/2024 10:42, Michal Simek wrote:
>>>>
>>>>
>>>> On 2/16/24 10:19, Krzysztof Kozlowski wrote:
>>>>> On 16/02/2024 09:51, Michal Simek wrote:
>>>>>> RTC has its own power domain on Xilinx Versal SOC that's why describe it as
>>>>>> optional property.
>>>>>>
>>>>>> Signed-off-by: Michal Simek <michal.simek@amd.com>
>>>>>> ---
>>>>>>
>>>>>>     Documentation/devicetree/bindings/rtc/xlnx,zynqmp-rtc.yaml | 3 +++
>>>>>>     1 file changed, 3 insertions(+)
>>>>>>
>>>>>
>>>>> But Versal is not described in this binding, is it? I see only one
>>>>> compatible.
>>>>
>>>> It is the same IP only as is on zynqmp with own power rail.
>>>
>>> Then you should have separate compatible, because they are not
>>> identical. It would also allow you to narrow the domains to versal and
>>> also require it (on versal).
>>
>> I can double check with HW guys but I am quite sure IP itself is exactly the
>> same. What it is different is that there is own power domain to it (not shared
>> one as is in zynqmp case).
> 
> What does it mean shared one? If several devices share power domain,
> then they all should have power-domains property.

Shared one means that the same power domain is shared with other IPs or simply 
enabled by default without any option to disable it.

Thanks,
Michal