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[PATCH v4 1/3] dt-bindings: hwlock: Adding brcmstb-hwspinlock support

Kamal Dasu posted 3 patches 1 month, 2 weeks ago
There is a newer version of this series
[PATCH v4 1/3] dt-bindings: hwlock: Adding brcmstb-hwspinlock support
Posted by Kamal Dasu 1 month, 2 weeks ago 
The Broadcom settop SoCs have hardware semaphores as part of the
"sundry" IP block which has other controls that do not belong anywhere
else e.g. pin/mux controls, SoC identification, drive strength, reset
controls, and other misc bits are part of this block.

Adding brcmstb hwspinlock bindings which allows hwlock driver
to iomap 16 hardware semaphore registers that are part of all
settop SoCs. The bindings use the common
"brcm,brcmstb-sun-top-ctrl-semaphore" compatible string reflecting the
actual hardware register block name.

Signed-off-by: Kamal Dasu <kamal.dasu@broadcom.com>
---
 .../hwlock/brcm,brcmstb-hwspinlock.yaml       | 45 +++++++++++++++++++
 1 file changed, 45 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/hwlock/brcm,brcmstb-hwspinlock.yaml

diff --git a/Documentation/devicetree/bindings/hwlock/brcm,brcmstb-hwspinlock.yaml b/Documentation/devicetree/bindings/hwlock/brcm,brcmstb-hwspinlock.yaml
new file mode 100644
index 000000000000..0a9a1bf19fe2
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwlock/brcm,brcmstb-hwspinlock.yaml
@@ -0,0 +1,45 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/hwlock/brcm,brcmstb-hwspinlock.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Broadcom Settop Sundry Block Hardware Semaphore
+
+description:
+  Broadcom settop SoCs contain 16 hardware semaphore registers
+  (SEMAPHORE_0 through SEMAPHORE_15) that provide hardware-arbitrated
+  mutual exclusion between drivers running on the SoC.
+
+  The semaphore registers belong to the sundry hardware block. The
+  node describes the semaphore register range carved out of the larger
+  sundry block address space.
+
+maintainers:
+  - Kamal Dasu <kamal.dasu@broadcom.com>
+
+properties:
+  compatible:
+    const: brcm,brcmstb-sun-top-ctrl-semaphore
+
+  "#hwlock-cells":
+    const: 1
+
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - "#hwlock-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    hwlock@8404038 {
+        compatible = "brcm,brcmstb-sun-top-ctrl-semaphore";
+        reg = <0x8404038 0x40>;
+        #hwlock-cells = <1>;
+    };
+
-- 
2.34.1
Re: [PATCH v4 1/3] dt-bindings: hwlock: Adding brcmstb-hwspinlock support
Posted by Krzysztof Kozlowski 1 month, 2 weeks ago 
On Thu, Feb 19, 2026 at 04:57:00PM -0500, Kamal Dasu wrote:
> The Broadcom settop SoCs have hardware semaphores as part of the
> "sundry" IP block which has other controls that do not belong anywhere
> else e.g. pin/mux controls, SoC identification, drive strength, reset
> controls, and other misc bits are part of this block.
> 
> Adding brcmstb hwspinlock bindings which allows hwlock driver
> to iomap 16 hardware semaphore registers that are part of all
> settop SoCs. The bindings use the common
> "brcm,brcmstb-sun-top-ctrl-semaphore" compatible string reflecting the
> actual hardware register block name.
> 
> Signed-off-by: Kamal Dasu <kamal.dasu@broadcom.com>
> ---
>  .../hwlock/brcm,brcmstb-hwspinlock.yaml       | 45 +++++++++++++++++++
>  1 file changed, 45 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/hwlock/brcm,brcmstb-hwspinlock.yaml
> 
> diff --git a/Documentation/devicetree/bindings/hwlock/brcm,brcmstb-hwspinlock.yaml b/Documentation/devicetree/bindings/hwlock/brcm,brcmstb-hwspinlock.yaml
> new file mode 100644
> index 000000000000..0a9a1bf19fe2
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwlock/brcm,brcmstb-hwspinlock.yaml

Incorrect filename. It must match compatible.

> @@ -0,0 +1,45 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/hwlock/brcm,brcmstb-hwspinlock.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Broadcom Settop Sundry Block Hardware Semaphore
> +
> +description:
> +  Broadcom settop SoCs contain 16 hardware semaphore registers
> +  (SEMAPHORE_0 through SEMAPHORE_15) that provide hardware-arbitrated
> +  mutual exclusion between drivers running on the SoC.
> +
> +  The semaphore registers belong to the sundry hardware block. The
> +  node describes the semaphore register range carved out of the larger
> +  sundry block address space.
> +
> +maintainers:
> +  - Kamal Dasu <kamal.dasu@broadcom.com>
> +
> +properties:
> +  compatible:
> +    const: brcm,brcmstb-sun-top-ctrl-semaphore

That's still not SoC specific.

Best regards,
Krzysztof
Re: [PATCH v4 1/3] dt-bindings: hwlock: Adding brcmstb-hwspinlock support
Posted by Krzysztof Kozlowski 1 month, 2 weeks ago 
On 20/02/2026 08:30, Krzysztof Kozlowski wrote:
>> +title: Broadcom Settop Sundry Block Hardware Semaphore
>> +
>> +description:
>> +  Broadcom settop SoCs contain 16 hardware semaphore registers
>> +  (SEMAPHORE_0 through SEMAPHORE_15) that provide hardware-arbitrated
>> +  mutual exclusion between drivers running on the SoC.
>> +
>> +  The semaphore registers belong to the sundry hardware block. The
>> +  node describes the semaphore register range carved out of the larger
>> +  sundry block address space.
>> +
>> +maintainers:
>> +  - Kamal Dasu <kamal.dasu@broadcom.com>
>> +
>> +properties:
>> +  compatible:
>> +    const: brcm,brcmstb-sun-top-ctrl-semaphore
> 
> That's still not SoC specific.

Heh, and I already asked for this at v2!

That's wasting my time, read again v2 feedback.

NAK


Best regards,
Krzysztof
Re: [PATCH v4 1/3] dt-bindings: hwlock: Adding brcmstb-hwspinlock support
Posted by Kamal Dasu 1 month, 1 week ago 
On Fri, Feb 20, 2026 at 2:31 AM Krzysztof Kozlowski <krzk@kernel.org> wrote:

> On 20/02/2026 08:30, Krzysztof Kozlowski wrote:
> >> +title: Broadcom Settop Sundry Block Hardware Semaphore
> >> +
> >> +description:
> >> +  Broadcom settop SoCs contain 16 hardware semaphore registers
> >> +  (SEMAPHORE_0 through SEMAPHORE_15) that provide hardware-arbitrated
> >> +  mutual exclusion between drivers running on the SoC.
> >> +
> >> +  The semaphore registers belong to the sundry hardware block. The
> >> +  node describes the semaphore register range carved out of the larger
> >> +  sundry block address space.
> >> +
> >> +maintainers:
> >> +  - Kamal Dasu <kamal.dasu@broadcom.com>
> >> +
> >> +properties:
> >> +  compatible:
> >> +    const: brcm,brcmstb-sun-top-ctrl-semaphore
> >
> > That's still not SoC specific.
>
> Heh, and I already asked for this at v2!
>
> Do you need to see SoC series in there, or you are looking for specific
structure in device tree, I have looked all the preceding hwlock drivers
and its inline with what they have in there.
e.g. +    const: brcm,brcmstb-7445-sun-top-ctrl-semaphore


> That's wasting my time, read again v2 feedback.
>
> Can you please point me to an example?


> NAK
>
>
> Best regards,
> Krzysztof
>

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