On Wed, 2021-06-02 at 11:58 -0500, Rob Herring wrote:

On Sun, May 30, 2021 at 12:52:33AM +0800, Hector Yuan wrote:

quoted

From: "Hector.Yuan" <redacted>

Add devicetree bindings for MediaTek HW driver.

Signed-off-by: Hector.Yuan <redacted>
---
 .../bindings/cpufreq/cpufreq-mediatek-hw.yaml      |   71 ++++++++++++++++++++
 1 file changed, 71 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/cpufreq/cpufreq-mediatek-hw.yaml

diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-mediatek-hw.yaml b/Documentation/devicetree/bindings/cpufreq/cpufreq-mediatek-hw.yaml
new file mode 100644
index 0000000..1aa4d54
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-mediatek-hw.yaml

@@ -0,0 +1,71 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/cpufreq/cpufreq-mediatek-hw.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MediaTek's CPUFREQ Bindings
+
+maintainers:
+  - Hector Yuan <hector.yuan@mediatek.com>
+
+description:
+  CPUFREQ HW is a hardware engine used by MediaTek
+  SoCs to manage frequency in hardware. It is capable of controlling frequency
+  for multiple clusters.
+
+properties:
+  compatible:
+    const: mediatek,cpufreq-hw
+
+  reg:
+    minItems: 1
+    maxItems: 2
+    description: |
+      Addresses and sizes for the memory of the
+      HW bases in each frequency domain.
+
+  "#performance-domain-cells":
+    description:
+      Number of cells in a performance domain specifier. Typically 0 for nodes
+      representing a single performance domain and 1 for nodes providing
+      multiple performance domains (e.g. performance controllers), but can be
+      any value as specified by device tree binding documentation of particular
+      provider.
+    enum: [ 0, 1 ]

Can't you restrict this to be 1 for Mediatek h/w? Even if you sometimes 
have a single domain, it's probably more simple for the driver if this 
is fixed.

OK, I will restrict this as 1 in next version.

quoted

+
+required:
+  - compatible
+  - reg
+  - "#performance-domain-cells"
+
+additionalProperties: true

Should be false.

OK, thanks

quoted

+
+examples:
+  - |
+    cpus {
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            cpu0: cpu@0 {
+                device_type = "cpu";
+                compatible = "arm,cortex-a55";
+                enable-method = "psci";
+                performance-domains = <&performance 0>;
+                reg = <0x000>;
+            };
+    };
+
+    /* ... */
+
+    soc {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        performance: performance-controller@11bc00 {
+            compatible = "mediatek,cpufreq-hw";
+            reg = <0 0x0011bc10 0 0x120>, <0 0x0011bd30 0 0x120>;
+
+            #performance-domain-cells = <1>;
+        };
+    };
-- 
1.7.9.5