diff mbox series

[v1,3/7] dt-bindings: rtc: add refclk to mpfs-rtc

Message ID 20220408143646.3693104-4-conor.dooley@microchip.com (mailing list archive)
State New, archived
Headers show
Series Add rtc refclk support for PolarFire SoC | expand

Commit Message

Conor Dooley April 8, 2022, 2:36 p.m. UTC 
The rtc on PolarFire SoC does not use the AHB clock as its reference
frequency, but rather a 1 MHz refclk that it shares with MTIMER. Add
this second clock to the binding as a required property.

Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
 .../bindings/rtc/microchip,mfps-rtc.yaml           | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

Comments

Krzysztof Kozlowski April 8, 2022, 2:56 p.m. UTC | #1 
On 08/04/2022 16:36, Conor Dooley wrote:
> The rtc on PolarFire SoC does not use the AHB clock as its reference
> frequency, but rather a 1 MHz refclk that it shares with MTIMER. Add
> this second clock to the binding as a required property.
> 
> Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
> ---
>  .../bindings/rtc/microchip,mfps-rtc.yaml           | 14 +++++++++++---
>  1 file changed, 11 insertions(+), 3 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/rtc/microchip,mfps-rtc.yaml b/Documentation/devicetree/bindings/rtc/microchip,mfps-rtc.yaml
> index a2e984ea3553..1ffd97dbe6b9 100644
> --- a/Documentation/devicetree/bindings/rtc/microchip,mfps-rtc.yaml
> +++ b/Documentation/devicetree/bindings/rtc/microchip,mfps-rtc.yaml
> @@ -31,11 +31,18 @@ properties:
>            to that of the RTC's count register.
>  
>    clocks:
> -    maxItems: 1
> +    items:
> +      - description: |
> +          AHB clock
> +      - description: |

Same as your patch #1 - this breaks the ABI.

Best regards,
Krzysztof
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/rtc/microchip,mfps-rtc.yaml b/Documentation/devicetree/bindings/rtc/microchip,mfps-rtc.yaml
index a2e984ea3553..1ffd97dbe6b9 100644
--- a/Documentation/devicetree/bindings/rtc/microchip,mfps-rtc.yaml
+++ b/Documentation/devicetree/bindings/rtc/microchip,mfps-rtc.yaml
@@ -31,11 +31,18 @@  properties:
           to that of the RTC's count register.
 
   clocks:
-    maxItems: 1
+    items:
+      - description: |
+          AHB clock
+      - description: |
+          Reference clock: divided by the prescaler to create a time-based strobe (typically 1 Hz)
+          for the calendar counter. By default, the rtc on the PolarFire SoC shares it's reference
+          with MTIMER so this will be a 1 MHz clock.
 
   clock-names:
     items:
       - const: rtc
+      - const: rtcref
 
 required:
   - compatible
@@ -48,11 +55,12 @@  additionalProperties: false
 
 examples:
   - |
+    #include "dt-bindings/clock/microchip,mpfs-clock.h"
     rtc@20124000 {
         compatible = "microchip,mpfs-rtc";
         reg = <0x20124000 0x1000>;
-        clocks = <&clkcfg 21>;
-        clock-names = "rtc";
+        clocks = <&clkcfg CLK_RTC>, <&clkcfg CLK_RTCREF>;
+        clock-names = "rtc", "rtcref";
         interrupts = <80>, <81>;
     };
 ...