diff mbox series

[v5,1/3] dt-bindings: pwm: Add Xilinx AXI Timer

Message ID 20210719221322.3723009-1-sean.anderson@seco.com (mailing list archive)
State New, archived
Headers show
Series [v5,1/3] dt-bindings: pwm: Add Xilinx AXI Timer | expand

Commit Message

Sean Anderson July 19, 2021, 10:13 p.m. UTC
This adds a binding for the Xilinx LogiCORE IP AXI Timer. This device is a
"soft" block, so it has some parameters which would not be configurable in
most hardware. This binding is usually automatically generated by Xilinx's
tools, so the names and values of some properties should be kept as they
are, if possible. In addition, this binding is already in the kernel at
arch/microblaze/boot/dts/system.dts, and in user software such as QEMU.

The existing driver uses the clock-frequency property, or alternatively the
/cpus/timebase-frequency property as its frequency input. Because these
properties are deprecated, they have not been included with this schema.
All new bindings should use the clocks/clock-names properties to specify
the parent clock.

Because we need to init timer devices so early in boot, we determine if we
should use the PWM driver or the clocksource/clockevent driver by the
presence/absence, respectively, of #pwm-cells. Because both counters are
used by the PWM, there is no need for a separate property specifying which
counters are to be used for the PWM.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
---

Changes in v5:
- Update commit message to reflect revisions
- Fix indentation lint
- Add example for timer binding
- Remove xlnx,axi-timer-2.0 compatible string
- Move schema into the timer directory

Changes in v4:
- Remove references to generate polarity so this can get merged
- Predicate PWM driver on the presence of #pwm-cells
- Make some properties optional for clocksource drivers

Changes in v3:
- Mark all boolean-as-int properties as deprecated
- Add xlnx,pwm and xlnx,gen?-active-low properties.
- Make newer replacement properties mutually-exclusive with what they
  replace
- Add an example with non-deprecated properties only.

Changes in v2:
- Use 32-bit addresses for example binding

 .../bindings/timer/xlnx,xps-timer.yaml        | 91 +++++++++++++++++++
 1 file changed, 91 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/timer/xlnx,xps-timer.yaml

Comments

Rob Herring (Arm) July 20, 2021, 1:11 p.m. UTC | #1
On Mon, 19 Jul 2021 18:13:20 -0400, Sean Anderson wrote:
> This adds a binding for the Xilinx LogiCORE IP AXI Timer. This device is a
> "soft" block, so it has some parameters which would not be configurable in
> most hardware. This binding is usually automatically generated by Xilinx's
> tools, so the names and values of some properties should be kept as they
> are, if possible. In addition, this binding is already in the kernel at
> arch/microblaze/boot/dts/system.dts, and in user software such as QEMU.
> 
> The existing driver uses the clock-frequency property, or alternatively the
> /cpus/timebase-frequency property as its frequency input. Because these
> properties are deprecated, they have not been included with this schema.
> All new bindings should use the clocks/clock-names properties to specify
> the parent clock.
> 
> Because we need to init timer devices so early in boot, we determine if we
> should use the PWM driver or the clocksource/clockevent driver by the
> presence/absence, respectively, of #pwm-cells. Because both counters are
> used by the PWM, there is no need for a separate property specifying which
> counters are to be used for the PWM.
> 
> Signed-off-by: Sean Anderson <sean.anderson@seco.com>
> ---
> 
> Changes in v5:
> - Update commit message to reflect revisions
> - Fix indentation lint
> - Add example for timer binding
> - Remove xlnx,axi-timer-2.0 compatible string
> - Move schema into the timer directory
> 
> Changes in v4:
> - Remove references to generate polarity so this can get merged
> - Predicate PWM driver on the presence of #pwm-cells
> - Make some properties optional for clocksource drivers
> 
> Changes in v3:
> - Mark all boolean-as-int properties as deprecated
> - Add xlnx,pwm and xlnx,gen?-active-low properties.
> - Make newer replacement properties mutually-exclusive with what they
>   replace
> - Add an example with non-deprecated properties only.
> 
> Changes in v2:
> - Use 32-bit addresses for example binding
> 
>  .../bindings/timer/xlnx,xps-timer.yaml        | 91 +++++++++++++++++++
>  1 file changed, 91 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/timer/xlnx,xps-timer.yaml
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
./Documentation/devicetree/bindings/timer/xlnx,xps-timer.yaml: $id: relative path/filename doesn't match actual path or filename
	expected: http://devicetree.org/schemas/timer/xlnx,xps-timer.yaml#
\ndoc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/patch/1507329

This check can fail if there are any dependencies. The base for a patch
series is generally the most recent rc1.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit.
Sean Anderson July 20, 2021, 9:45 p.m. UTC | #2
On 7/20/21 9:11 AM, Rob Herring wrote:
> On Mon, 19 Jul 2021 18:13:20 -0400, Sean Anderson wrote:
>> This adds a binding for the Xilinx LogiCORE IP AXI Timer. This device is a
>> "soft" block, so it has some parameters which would not be configurable in
>> most hardware. This binding is usually automatically generated by Xilinx's
>> tools, so the names and values of some properties should be kept as they
>> are, if possible. In addition, this binding is already in the kernel at
>> arch/microblaze/boot/dts/system.dts, and in user software such as QEMU.
>> 
>> The existing driver uses the clock-frequency property, or alternatively the
>> /cpus/timebase-frequency property as its frequency input. Because these
>> properties are deprecated, they have not been included with this schema.
>> All new bindings should use the clocks/clock-names properties to specify
>> the parent clock.
>> 
>> Because we need to init timer devices so early in boot, we determine if we
>> should use the PWM driver or the clocksource/clockevent driver by the
>> presence/absence, respectively, of #pwm-cells. Because both counters are
>> used by the PWM, there is no need for a separate property specifying which
>> counters are to be used for the PWM.
>> 
>> Signed-off-by: Sean Anderson <sean.anderson@seco.com>
>> ---
>> 
>> Changes in v5:
>> - Update commit message to reflect revisions
>> - Fix indentation lint
>> - Add example for timer binding
>> - Remove xlnx,axi-timer-2.0 compatible string
>> - Move schema into the timer directory
>> 
>> Changes in v4:
>> - Remove references to generate polarity so this can get merged
>> - Predicate PWM driver on the presence of #pwm-cells
>> - Make some properties optional for clocksource drivers
>> 
>> Changes in v3:
>> - Mark all boolean-as-int properties as deprecated
>> - Add xlnx,pwm and xlnx,gen?-active-low properties.
>> - Make newer replacement properties mutually-exclusive with what they
>>   replace
>> - Add an example with non-deprecated properties only.
>> 
>> Changes in v2:
>> - Use 32-bit addresses for example binding
>> 
>>  .../bindings/timer/xlnx,xps-timer.yaml        | 91 +++++++++++++++++++
>>  1 file changed, 91 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/timer/xlnx,xps-timer.yaml
>> 
> 
> My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
> on your patch (DT_CHECKER_FLAGS is new in v5.13):
> 
> yamllint warnings/errors:
> 
> dtschema/dtc warnings/errors:
> ./Documentation/devicetree/bindings/timer/xlnx,xps-timer.yaml: $id: relative path/filename doesn't match actual path or filename
> 	expected: http://devicetree.org/schemas/timer/xlnx,xps-timer.yaml#
> \ndoc reference errors (make refcheckdocs):

Ah, looks like I neglected to re-run tests after moving this file. Will fix in v6.

--Sean

> 
> See https://patchwork.ozlabs.org/patch/1507329
> 
> This check can fail if there are any dependencies. The base for a patch
> series is generally the most recent rc1.
> 
> If you already ran 'make dt_binding_check' and didn't see the above
> error(s), then make sure 'yamllint' is installed and dt-schema is up to
> date:
> 
> pip3 install dtschema --upgrade
> 
> Please check and re-submit.
>
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/timer/xlnx,xps-timer.yaml b/Documentation/devicetree/bindings/timer/xlnx,xps-timer.yaml
new file mode 100644
index 000000000000..e5439653dc03
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/xlnx,xps-timer.yaml
@@ -0,0 +1,91 @@ 
+# SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pwm/xlnx,axi-timer.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Xilinx LogiCORE IP AXI Timer Device Tree Binding
+
+maintainers:
+  - Sean Anderson <sean.anderson@seco.com>
+
+properties:
+  compatible:
+    contains:
+      const: xlnx,xps-timer-1.00.a
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    const: s_axi_aclk
+
+  interrupts:
+    maxItems: 1
+
+  reg:
+    maxItems: 1
+
+  xlnx,count-width:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    minimum: 8
+    maximum: 32
+    default: 32
+    description:
+      The width of the counter(s), in bits.
+
+  xlnx,one-timer-only:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    enum: [ 0, 1 ]
+    description:
+      Whether only one timer is present in this block.
+
+required:
+  - compatible
+  - reg
+  - xlnx,one-timer-only
+
+allOf:
+  - if:
+      required:
+        - '#pwm-cells'
+    then:
+      allOf:
+        - required:
+            - clocks
+        - properties:
+            xlnx,one-timer-only:
+              const: 0
+    else:
+      required:
+        - interrupts
+  - if:
+      required:
+        - clocks
+    then:
+      required:
+        - clock-names
+
+additionalProperties: true
+
+examples:
+  - |
+    timer@800e0000 {
+        clock-names = "s_axi_aclk";
+        clocks = <&zynqmp_clk 71>;
+        compatible = "xlnx,xps-timer-1.00.a";
+        reg = <0x800e0000 0x10000>;
+        interrupts = <0 39 2>;
+        xlnx,count-width = <16>;
+        xlnx,one-timer-only = <0x0>;
+    };
+
+    timer@800f0000 {
+        #pwm-cells = <0>;
+        clock-names = "s_axi_aclk";
+        clocks = <&zynqmp_clk 71>;
+        compatible = "xlnx,xps-timer-1.00.a";
+        reg = <0x800e0000 0x10000>;
+        xlnx,count-width = <32>;
+        xlnx,one-timer-only = <0x0>;
+    };