[v3] ufs: ufs-qcom: Add support firmware managed platforms

[PATCH V3 2/4] dt-bindings: ufs: Document bindings for SA8255P UFS Host Controller

Posted by Ram Kumar Dwivedi 1 month, 1 week ago

Document the device tree bindings for UFS host controller on
Qualcomm SA8255P platform which integrates firmware-managed
resources.

The platform firmware implements the SCMI server and manages
resources such as the PHY, clocks, regulators and resets via the
SCMI power protocol. As a result, the OS-visible DT only describes
the controller’s MMIO, interrupt, IOMMU and power-domain interfaces.

The generic "qcom,ufshc" and "jedec,ufs-2.0" compatible strings are
removed from the binding, since this firmware managed design won't
be compatible with the drivers doing full resource management.

Co-developed-by: Anjana Hari <anjana.hari@oss.qualcomm.com>
Signed-off-by: Anjana Hari <anjana.hari@oss.qualcomm.com>
Signed-off-by: Ram Kumar Dwivedi <ram.dwivedi@oss.qualcomm.com>
---
 .../bindings/ufs/qcom,sa8255p-ufshc.yaml      | 62 +++++++++++++++++++
 1 file changed, 62 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/ufs/qcom,sa8255p-ufshc.yaml

diff --git a/Documentation/devicetree/bindings/ufs/qcom,sa8255p-ufshc.yaml b/Documentation/devicetree/bindings/ufs/qcom,sa8255p-ufshc.yaml
new file mode 100644
index 000000000000..846a3552a9e4
--- /dev/null
+++ b/Documentation/devicetree/bindings/ufs/qcom,sa8255p-ufshc.yaml
@@ -0,0 +1,62 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/ufs/qcom,sa8255p-ufshc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm SA8255P UFS Host Controller
+
+maintainers:
+  - Ram Kumar Dwivedi <ram.dwivedi@oss.qualcomm.com>
+  - Anjana Hari <anjana.hari@oss.qualcomm.com>
+
+properties:
+  compatible:
+    const: qcom,sa8255p-ufshc
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  iommus:
+    maxItems: 1
+
+  dma-coherent: true
+
+  power-domains:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - power-domains
+  - iommus
+  - dma-coherent
+
+allOf:
+  - $ref: ufs-common.yaml
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+    soc {
+        #address-cells = <1>;
+        #size-cells = <1>;
+
+        ufshc@1d84000 {
+            compatible = "qcom,sa8255p-ufshc";
+            reg = <0x01d84000 0x3000>;
+            interrupts = <GIC_SPI 265 IRQ_TYPE_LEVEL_HIGH>;
+            lanes-per-direction = <2>;
+
+            iommus = <&apps_smmu 0x100 0x0>;
+            power-domains = <&scmi3_pd 0>;
+            dma-coherent;
+        };
+    };
-- 
2.34.1

Re: [PATCH V3 2/4] dt-bindings: ufs: Document bindings for SA8255P UFS Host Controller

Posted by Dmitry Baryshkov 1 month, 1 week ago

On Wed, Dec 31, 2025 at 10:25:51AM +0530, Ram Kumar Dwivedi wrote:
> Document the device tree bindings for UFS host controller on
> Qualcomm SA8255P platform which integrates firmware-managed
> resources.
> 
> The platform firmware implements the SCMI server and manages
> resources such as the PHY, clocks, regulators and resets via the
> SCMI power protocol. As a result, the OS-visible DT only describes
> the controller’s MMIO, interrupt, IOMMU and power-domain interfaces.
> 
> The generic "qcom,ufshc" and "jedec,ufs-2.0" compatible strings are
> removed from the binding, since this firmware managed design won't
> be compatible with the drivers doing full resource management.
> 
> Co-developed-by: Anjana Hari <anjana.hari@oss.qualcomm.com>
> Signed-off-by: Anjana Hari <anjana.hari@oss.qualcomm.com>
> Signed-off-by: Ram Kumar Dwivedi <ram.dwivedi@oss.qualcomm.com>
> ---
>  .../bindings/ufs/qcom,sa8255p-ufshc.yaml      | 62 +++++++++++++++++++
>  1 file changed, 62 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/ufs/qcom,sa8255p-ufshc.yaml
> 
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +
> +    soc {
> +        #address-cells = <1>;
> +        #size-cells = <1>;

This didn't really improve. You don't need 'soc' node at all. Please
drop it.

> +
> +        ufshc@1d84000 {
> +            compatible = "qcom,sa8255p-ufshc";
> +            reg = <0x01d84000 0x3000>;
> +            interrupts = <GIC_SPI 265 IRQ_TYPE_LEVEL_HIGH>;
> +            lanes-per-direction = <2>;
> +
> +            iommus = <&apps_smmu 0x100 0x0>;
> +            power-domains = <&scmi3_pd 0>;
> +            dma-coherent;
> +        };
> +    };
> -- 
> 2.34.1
> 

-- 
With best wishes
Dmitry

Re: [PATCH V3 2/4] dt-bindings: ufs: Document bindings for SA8255P UFS Host Controller

Posted by Krzysztof Kozlowski 1 month, 1 week ago

On 31/12/2025 06:19, Dmitry Baryshkov wrote:
> On Wed, Dec 31, 2025 at 10:25:51AM +0530, Ram Kumar Dwivedi wrote:
>> Document the device tree bindings for UFS host controller on
>> Qualcomm SA8255P platform which integrates firmware-managed
>> resources.
>>
>> The platform firmware implements the SCMI server and manages
>> resources such as the PHY, clocks, regulators and resets via the
>> SCMI power protocol. As a result, the OS-visible DT only describes
>> the controller’s MMIO, interrupt, IOMMU and power-domain interfaces.
>>
>> The generic "qcom,ufshc" and "jedec,ufs-2.0" compatible strings are
>> removed from the binding, since this firmware managed design won't
>> be compatible with the drivers doing full resource management.
>>
>> Co-developed-by: Anjana Hari <anjana.hari@oss.qualcomm.com>
>> Signed-off-by: Anjana Hari <anjana.hari@oss.qualcomm.com>
>> Signed-off-by: Ram Kumar Dwivedi <ram.dwivedi@oss.qualcomm.com>
>> ---
>>  .../bindings/ufs/qcom,sa8255p-ufshc.yaml      | 62 +++++++++++++++++++
>>  1 file changed, 62 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/ufs/qcom,sa8255p-ufshc.yaml
>>
>> +
>> +examples:
>> +  - |
>> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
>> +
>> +    soc {
>> +        #address-cells = <1>;
>> +        #size-cells = <1>;
> 
> This didn't really improve. You don't need 'soc' node at all. Please
> drop it.
> 

It was already asked by Bjorn, then I reminded that. So I wonder if
repeating three times will work?

Feels like a waste of our time if same feedback has to be repeated three
times.

Best regards,
Krzysztof

Re: [PATCH V3 2/4] dt-bindings: ufs: Document bindings for SA8255P UFS Host Controller

Posted by Ram Kumar Dwivedi 1 month ago


On 31-Dec-25 1:23 PM, Krzysztof Kozlowski wrote:
> On 31/12/2025 06:19, Dmitry Baryshkov wrote:
>> On Wed, Dec 31, 2025 at 10:25:51AM +0530, Ram Kumar Dwivedi wrote:
>>> Document the device tree bindings for UFS host controller on
>>> Qualcomm SA8255P platform which integrates firmware-managed
>>> resources.
>>>
>>> The platform firmware implements the SCMI server and manages
>>> resources such as the PHY, clocks, regulators and resets via the
>>> SCMI power protocol. As a result, the OS-visible DT only describes
>>> the controller’s MMIO, interrupt, IOMMU and power-domain interfaces.
>>>
>>> The generic "qcom,ufshc" and "jedec,ufs-2.0" compatible strings are
>>> removed from the binding, since this firmware managed design won't
>>> be compatible with the drivers doing full resource management.
>>>
>>> Co-developed-by: Anjana Hari <anjana.hari@oss.qualcomm.com>
>>> Signed-off-by: Anjana Hari <anjana.hari@oss.qualcomm.com>
>>> Signed-off-by: Ram Kumar Dwivedi <ram.dwivedi@oss.qualcomm.com>
>>> ---
>>>  .../bindings/ufs/qcom,sa8255p-ufshc.yaml      | 62 +++++++++++++++++++
>>>  1 file changed, 62 insertions(+)
>>>  create mode 100644 Documentation/devicetree/bindings/ufs/qcom,sa8255p-ufshc.yaml
>>>
>>> +
>>> +examples:
>>> +  - |
>>> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
>>> +
>>> +    soc {
>>> +        #address-cells = <1>;
>>> +        #size-cells = <1>;
>>
>> This didn't really improve. You don't need 'soc' node at all. Please
>> drop it.
>>
> 
> It was already asked by Bjorn, then I reminded that. So I wonder if
> repeating three times will work?
> 
> Feels like a waste of our time if same feedback has to be repeated three
> times.

Hi Krzysztof and Dmitry,

I have removed the address-cells and size-cells in latest patchset.

Thanks,
Ram.


> 
> Best regards,
> Krzysztof