diff mbox series

[v2,1/3] dt-bindings: watchdog: sunxi: Add compatible for R329

Message ID 20210805045716.46141-1-samuel@sholland.org (mailing list archive)
State Superseded
Headers show
Series [v2,1/3] dt-bindings: watchdog: sunxi: Add compatible for R329 | expand

Commit Message

Samuel Holland Aug. 5, 2021, 4:57 a.m. UTC
On existing SoCs, the watchdog has a single clock input: HOSC (OSC24M)
divided by 750.  However, starting with R329, LOSC (OSC32k) is added as
an alternative clock source, with a bit to switch between them.

Since 24 MHz / 750 == 32 kHz, not 32.768 kHz, the hardware adjusts the
cycle counts to keep the timeouts independent of the clock source. This
keeps the programming interface backward-compatible.

R329 also adds two new registers, to allow software to immediately drive
the SoC reset signal.

Signed-off-by: Samuel Holland <samuel@sholland.org>
---
Changes v1 to v2:
 - Switch from enum to const
 - Add descriptions to "clocks" items

 .../watchdog/allwinner,sun4i-a10-wdt.yaml     | 32 ++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

Comments

Rob Herring (Arm) Aug. 13, 2021, 5:46 p.m. UTC | #1
On Wed, Aug 04, 2021 at 11:57:14PM -0500, Samuel Holland wrote:
> On existing SoCs, the watchdog has a single clock input: HOSC (OSC24M)
> divided by 750.  However, starting with R329, LOSC (OSC32k) is added as
> an alternative clock source, with a bit to switch between them.
> 
> Since 24 MHz / 750 == 32 kHz, not 32.768 kHz, the hardware adjusts the
> cycle counts to keep the timeouts independent of the clock source. This
> keeps the programming interface backward-compatible.
> 
> R329 also adds two new registers, to allow software to immediately drive
> the SoC reset signal.
> 
> Signed-off-by: Samuel Holland <samuel@sholland.org>
> ---
> Changes v1 to v2:
>  - Switch from enum to const
>  - Add descriptions to "clocks" items
> 
>  .../watchdog/allwinner,sun4i-a10-wdt.yaml     | 32 ++++++++++++++++++-
>  1 file changed, 31 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
> index 9aa3c313c49f..8fa5b0d32381 100644
> --- a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
> +++ b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
> @@ -24,6 +24,7 @@ properties:
>                - allwinner,sun50i-a100-wdt
>                - allwinner,sun50i-h6-wdt
>                - allwinner,sun50i-h616-wdt
> +              - allwinner,sun50i-r329-wdt
>            - const: allwinner,sun6i-a31-wdt
>        - items:
>            - const: allwinner,suniv-f1c100s-wdt
> @@ -33,7 +34,18 @@ properties:
>      maxItems: 1
>  
>    clocks:
> -    maxItems: 1
> +    minItems: 1
> +    maxItems: 2
> +    items:
> +      - description: High-frequency oscillator input, divided internally
> +      - description: Low-frequency oscillator input, only found on some variants
> +
> +  clock-names:
> +    minItems: 1
> +    maxItems: 2
> +    items:
> +      - const: hosc
> +      - const: losc
>  
>    interrupts:
>      maxItems: 1
> @@ -44,6 +56,24 @@ required:
>    - clocks
>    - interrupts
>  
> +if:
> +  properties:
> +    compatible:
> +      contains:
> +        enum:
> +          - allwinner,sun50i-r329-wdt
> +
> +then:
> +  properties:
> +    clocks:
> +      minItems: 2
> +
> +    clock-names:
> +      minItems: 2
> +
> +  required:
> +    - clock-names

Needs an else clause with 'maxItems: 1' or is the 2nd clock now valid 
for all?

> +
>  unevaluatedProperties: false
>  
>  examples:
> -- 
> 2.31.1
> 
>
Maxime Ripard Aug. 18, 2021, 9:07 a.m. UTC | #2
Hi,

On Wed, Aug 04, 2021 at 11:57:14PM -0500, Samuel Holland wrote:
> On existing SoCs, the watchdog has a single clock input: HOSC (OSC24M)
> divided by 750.  However, starting with R329, LOSC (OSC32k) is added as
> an alternative clock source, with a bit to switch between them.
> 
> Since 24 MHz / 750 == 32 kHz, not 32.768 kHz, the hardware adjusts the
> cycle counts to keep the timeouts independent of the clock source. This
> keeps the programming interface backward-compatible.
> 
> R329 also adds two new registers, to allow software to immediately drive
> the SoC reset signal.
> 
> Signed-off-by: Samuel Holland <samuel@sholland.org>
> ---
> Changes v1 to v2:
>  - Switch from enum to const
>  - Add descriptions to "clocks" items
> 
>  .../watchdog/allwinner,sun4i-a10-wdt.yaml     | 32 ++++++++++++++++++-
>  1 file changed, 31 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
> index 9aa3c313c49f..8fa5b0d32381 100644
> --- a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
> +++ b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
> @@ -24,6 +24,7 @@ properties:
>                - allwinner,sun50i-a100-wdt
>                - allwinner,sun50i-h6-wdt
>                - allwinner,sun50i-h616-wdt
> +              - allwinner,sun50i-r329-wdt
>            - const: allwinner,sun6i-a31-wdt
>        - items:
>            - const: allwinner,suniv-f1c100s-wdt
> @@ -33,7 +34,18 @@ properties:
>      maxItems: 1
>  
>    clocks:
> -    maxItems: 1
> +    minItems: 1
> +    maxItems: 2
> +    items:
> +      - description: High-frequency oscillator input, divided internally
> +      - description: Low-frequency oscillator input, only found on some variants
> +
> +  clock-names:
> +    minItems: 1
> +    maxItems: 2
> +    items:
> +      - const: hosc
> +      - const: losc
>  
>    interrupts:
>      maxItems: 1
> @@ -44,6 +56,24 @@ required:
>    - clocks
>    - interrupts
>  
> +if:
> +  properties:
> +    compatible:
> +      contains:
> +        enum:
> +          - allwinner,sun50i-r329-wdt
> +
> +then:
> +  properties:
> +    clocks:
> +      minItems: 2
> +
> +    clock-names:
> +      minItems: 2
> +
> +  required:
> +    - clock-names
> +

We should also make sure through an else clause that all the other SoCs
have a length of one for both clocks and clock-names

Also, it looks like you forgot the patch to enable the compatible in the
driver?

Maxime
Samuel Holland Aug. 20, 2021, 4:04 a.m. UTC | #3
On 8/18/21 4:07 AM, Maxime Ripard wrote:
> Hi,
> 
> On Wed, Aug 04, 2021 at 11:57:14PM -0500, Samuel Holland wrote:
>> On existing SoCs, the watchdog has a single clock input: HOSC (OSC24M)
>> divided by 750.  However, starting with R329, LOSC (OSC32k) is added as
>> an alternative clock source, with a bit to switch between them.
>>
>> Since 24 MHz / 750 == 32 kHz, not 32.768 kHz, the hardware adjusts the
>> cycle counts to keep the timeouts independent of the clock source. This
>> keeps the programming interface backward-compatible.
>>
>> R329 also adds two new registers, to allow software to immediately drive
>> the SoC reset signal.
>>
>> Signed-off-by: Samuel Holland <samuel@sholland.org>
>> ---
>> Changes v1 to v2:
>>  - Switch from enum to const
>>  - Add descriptions to "clocks" items
>>
>>  .../watchdog/allwinner,sun4i-a10-wdt.yaml     | 32 ++++++++++++++++++-
>>  1 file changed, 31 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
>> index 9aa3c313c49f..8fa5b0d32381 100644
>> --- a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
>> +++ b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
>> @@ -24,6 +24,7 @@ properties:
>>                - allwinner,sun50i-a100-wdt
>>                - allwinner,sun50i-h6-wdt
>>                - allwinner,sun50i-h616-wdt
>> +              - allwinner,sun50i-r329-wdt
>>            - const: allwinner,sun6i-a31-wdt
>>        - items:
>>            - const: allwinner,suniv-f1c100s-wdt
>> @@ -33,7 +34,18 @@ properties:
>>      maxItems: 1
>>  
>>    clocks:
>> -    maxItems: 1
>> +    minItems: 1
>> +    maxItems: 2
>> +    items:
>> +      - description: High-frequency oscillator input, divided internally
>> +      - description: Low-frequency oscillator input, only found on some variants
>> +
>> +  clock-names:
>> +    minItems: 1
>> +    maxItems: 2
>> +    items:
>> +      - const: hosc
>> +      - const: losc
>>  
>>    interrupts:
>>      maxItems: 1
>> @@ -44,6 +56,24 @@ required:
>>    - clocks
>>    - interrupts
>>  
>> +if:
>> +  properties:
>> +    compatible:
>> +      contains:
>> +        enum:
>> +          - allwinner,sun50i-r329-wdt
>> +
>> +then:
>> +  properties:
>> +    clocks:
>> +      minItems: 2
>> +
>> +    clock-names:
>> +      minItems: 2
>> +
>> +  required:
>> +    - clock-names
>> +
> 
> We should also make sure through an else clause that all the other SoCs
> have a length of one for both clocks and clock-names

Yes, I'll do that for v3.

> Also, it looks like you forgot the patch to enable the compatible in the
> driver?

R329 has a fallback to A31, so it doesn't need any changes to the driver.

Regards,
Samuel
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
index 9aa3c313c49f..8fa5b0d32381 100644
--- a/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
+++ b/Documentation/devicetree/bindings/watchdog/allwinner,sun4i-a10-wdt.yaml
@@ -24,6 +24,7 @@  properties:
               - allwinner,sun50i-a100-wdt
               - allwinner,sun50i-h6-wdt
               - allwinner,sun50i-h616-wdt
+              - allwinner,sun50i-r329-wdt
           - const: allwinner,sun6i-a31-wdt
       - items:
           - const: allwinner,suniv-f1c100s-wdt
@@ -33,7 +34,18 @@  properties:
     maxItems: 1
 
   clocks:
-    maxItems: 1
+    minItems: 1
+    maxItems: 2
+    items:
+      - description: High-frequency oscillator input, divided internally
+      - description: Low-frequency oscillator input, only found on some variants
+
+  clock-names:
+    minItems: 1
+    maxItems: 2
+    items:
+      - const: hosc
+      - const: losc
 
   interrupts:
     maxItems: 1
@@ -44,6 +56,24 @@  required:
   - clocks
   - interrupts
 
+if:
+  properties:
+    compatible:
+      contains:
+        enum:
+          - allwinner,sun50i-r329-wdt
+
+then:
+  properties:
+    clocks:
+      minItems: 2
+
+    clock-names:
+      minItems: 2
+
+  required:
+    - clock-names
+
 unevaluatedProperties: false
 
 examples: