Re: [PATCH 1/2] dt-bindings: thermal: loongson,ls2k-thermal: Add compatible for Loongson-2K0300

Hi Conor:

Thanks for your reply.

On Sat, Jul 11, 2026 at 12:21 AM Conor Dooley <[email protected]> wrote:
>
> On Fri, Jul 10, 2026 at 04:24:59PM +0800, Binbin Zhou wrote:
> > Add a new compatible string `loongson,ls2k0300-thermal` for the thermal
> > sensor found on the Loongson-2K0300 SoC.
> >
> > The hardware differs from the existing SoCs in its register layout: it
> > requires two register regions (one for the thermal sensor control and
> > another for the CPU ID).
> >
> > Update the binding to describe this new requirement.
> >
> > Signed-off-by: Binbin Zhou <[email protected]>
> > ---
> >  .../thermal/loongson,ls2k-thermal.yaml        | 68 ++++++++++++++-----
> >  1 file changed, 50 insertions(+), 18 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/thermal/loongson,ls2k-thermal.yaml b/Documentation/devicetree/bindings/thermal/loongson,ls2k-thermal.yaml
> > index 79e691b08341..b5cbfd201105 100644
> > --- a/Documentation/devicetree/bindings/thermal/loongson,ls2k-thermal.yaml
> > +++ b/Documentation/devicetree/bindings/thermal/loongson,ls2k-thermal.yaml
> > @@ -10,13 +10,11 @@ maintainers:
> >    - zhanghongchen <[email protected]>
> >    - Yinbo Zhu <[email protected]>
> >
> > -allOf:
> > -  - $ref: /schemas/thermal/thermal-sensor.yaml#
> > -
> >  properties:
> >    compatible:
> >      oneOf:
> >        - enum:
> > +          - loongson,ls2k0300-thermal
> >            - loongson,ls2k1000-thermal
> >            - loongson,ls2k2000-thermal
> >        - items:
> > @@ -39,23 +37,46 @@ required:
> >    - reg
> >    - interrupts
> >
> > -if:
> > -  properties:
> > -    compatible:
> > -      contains:
> > -        enum:
> > -          - loongson,ls2k2000-thermal
> > +allOf:
> > +  - $ref: /schemas/thermal/thermal-sensor.yaml#
> >
> > -then:
> > -  properties:
> > -    reg:
> > -      minItems: 2
> > -      maxItems: 2
> > +  - if:
> > +      properties:
> > +        compatible:
> > +          contains:
> > +            enum:
> > +              - loongson,ls2k0300-thermal
> > +    then:
> > +      properties:
> > +        reg:
> > +          items:
> > +            - description: Thermal base register region
> > +            - description: CPU ID register region
> >
> > -else:
> > -  properties:
> > -    reg:
> > -      maxItems: 1
> > +  - if:
> > +      properties:
> > +        compatible:
> > +          contains:
> > +            enum:
> > +              - loongson,ls2k1000-thermal
> > +    then:
> > +      properties:
> > +        reg:
> > +          items:
> > +            - description: Thermal base register region
> > +
> > +  - if:
> > +      properties:
> > +        compatible:
> > +          contains:
> > +            enum:
> > +              - loongson,ls2k2000-thermal
> > +    then:
> > +      properties:
> > +        reg:
> > +          items:
> > +            - description: Thermal base register region
> > +            - description: Thermal data output register region
> >
> >  unevaluatedProperties: false
> >
> > @@ -69,3 +90,14 @@ examples:
> >          interrupts = <7 IRQ_TYPE_LEVEL_LOW>;
> >          #thermal-sensor-cells = <1>;
> >      };
> > +
> > +  - |
> > +    #include <dt-bindings/interrupt-controller/irq.h>
> > +    thermal-sensor@16001500 {
> > +       compatible = "loongson,ls2k0300-thermal";
> > +       reg = <0x16001500 0x30>,
> > +             <0x16003ff0 0x8>;
>
> Quite frankly, the address and size of this look like the second
> register region here is actually a few bytes in a syscon that is being
> misrepresented.
> What lies at the addresses immediately before and after 0x16003ff0?

Yes, it can be viewed as part of the system configuration registers,
which appear somewhat disorganized. Within this section,
0x16003fe0–0x16003ffc represents eight chip ID registers.

0x16003fe0 --> the 4th chip id
0x16003fe4 --> the 5th chip id
0x16003fe8 --> the 6th chip id
0x16003fec --> the 7th chip id
0x16003ff0 --> the 0th chip id
0x16003ff4 --> the 1st chip id
0x16003ff8 --> the 2nd chip id
0x16003ffc --> the 3rd chip id

Perhaps I shouldn’t have referenced `0x16003ff0` separately here. It
would be more reasonable to declare the entire chip ID address space
as a separate syscon and have it referenced by thermal driver.

For example:

In DTS{i}:
chipid_syscon: syscon@16003fe0 {
       compatible = “loongson,ls2k0300-cphipid-syscon”, “syscon”;
       reg = <0x0 0x16003fe0 0x0 0x20>;
};

In thermal driver:
Use
`syscon_regmap_lookup_by_phandle(np, "loongson,chipid"); `
Or:
`syscon_regmap_lookup_by_compatible("loongson,ls2k0300-cphipid-syscon");`

get the chip id address space.

>
>
> Thanks,
> Conor.
>
> > +       interrupt-parent = <&liointc1>;
> > +       interrupts = <20 IRQ_TYPE_LEVEL_HIGH>;
> > +       #thermal-sensor-cells = <1>;
> > +    };
> > --
> > 2.52.0
> >

-- 
Thanks.
Binbin