[PATCH v2 0/4] rtc: rzn1: cleanups, R-Car Gen5 enablement

[PATCH v2 0/4] rtc: rzn1: cleanups, R-Car Gen5 enablement

[Wolfram Sang]

This series adds RTC support for the Renesas R-Car Gen5 SoCs.

Changes since v1:
* don't support non-interrupt mode in general, but implement it only for
  X5H while still requiring irqs for all other SoCs
* add tags to cleanup patches

Thanks for all the reviews of v1!

These patches have been tested on the original RZ/N1D board and the new
X5H Ironhide board. 'rtctest' passed on both SoCs. On X5H, some tests
are skipped, of course, because no alarms are supported.

'dt_binding_check' and 'dtbs_check' did not find any issues, for both,
RZ/N1D and R-Car X5H. I also verified for both that it rightfully
complains when irqs are different from what is expected.

A branch can be found here:

git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git renesas/x5h/rtc-experimental

Looking forward to comments.


Wolfram Sang (4):
  dt-bindings: rtc: rzn1: drop unneeded 'start-year' from example
  dt-bindings: rtc: rzn1: add SoC names next to their IDs
  dt-bindings: rtc: rzn1: add R-Car Gen5 support
  rtc: rzn1: add R-Car Gen5 support

 .../bindings/rtc/renesas,rzn1-rtc.yaml        | 33 +++++++++---
 drivers/rtc/rtc-rzn1.c                        | 54 ++++++++++++-------
 2 files changed, 61 insertions(+), 26 deletions(-)

-- 
2.53.0

[PATCH v2 1/4] dt-bindings: rtc: rzn1: drop unneeded 'start-year' from example

[Wolfram Sang]

We don't use 'start-year' in upstream DTs because the driver does the
right thing by default, ranging from 2000 to 2099. So, drop it from the
example, too.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
---
 Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml | 1 -
 1 file changed, 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
index ea7b039a91e7..e96007981c34 100644
--- a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
+++ b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
@@ -91,5 +91,4 @@ examples:
         clocks = <&sysctrl R9A06G032_HCLK_RTC>;
         clock-names = "hclk";
         power-domains = <&sysctrl>;
-        start-year = <2000>;
     };
-- 
2.53.0

Re: [PATCH v2 1/4] dt-bindings: rtc: rzn1: drop unneeded 'start-year' from example

[sashiko-bot]

> We don't use 'start-year' in upstream DTs because the driver does the
> right thing by default, ranging from 2000 to 2099. So, drop it from the
> example, too.
> 
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260916102520.24288-1-wsa+renesas@sang-engineering.com?part=1

Re: [PATCH v2 1/4] dt-bindings: rtc: rzn1: drop unneeded 'start-year' from example

[Geert Uytterhoeven]

On Wed, 16 Sept 2026 at 12:25, Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
> We don't use 'start-year' in upstream DTs because the driver does the
> right thing by default, ranging from 2000 to 2099. So, drop it from the
> example, too.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Acked-by: Conor Dooley <conor.dooley@microchip.com>

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

[PATCH v2 2/4] dt-bindings: rtc: rzn1: add SoC names next to their IDs

[Wolfram Sang]

This helps maintaining because the numbers are easy to confuse.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
---
 .../devicetree/bindings/rtc/renesas,rzn1-rtc.yaml      | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
index e96007981c34..7ea77cd0bee1 100644
--- a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
+++ b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
@@ -14,14 +14,14 @@ properties:
     oneOf:
       - items:
           - enum:
-              - renesas,r9a06g032-rtc
-          - const: renesas,rzn1-rtc
+              - renesas,r9a06g032-rtc # RZ/N1D
+          - const: renesas,rzn1-rtc   # RZ/N1
 
-      - const: renesas,r9a09g077-rtc
+      - const: renesas,r9a09g077-rtc  # RZ/T2H
 
       - items:
-          - const: renesas,r9a09g087-rtc
-          - const: renesas,r9a09g077-rtc
+          - const: renesas,r9a09g087-rtc  # RZ/N2H
+          - const: renesas,r9a09g077-rtc  # RZ/T2H
 
   reg:
     maxItems: 1
-- 
2.53.0

Re: [PATCH v2 2/4] dt-bindings: rtc: rzn1: add SoC names next to their IDs

[sashiko-bot]

> This helps maintaining because the numbers are easy to confuse.
> 
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260916102520.24288-1-wsa+renesas@sang-engineering.com?part=2

Re: [PATCH v2 2/4] dt-bindings: rtc: rzn1: add SoC names next to their IDs

[Geert Uytterhoeven]

On Wed, 16 Sept 2026 at 12:25, Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
> This helps maintaining because the numbers are easy to confuse.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Acked-by: Conor Dooley <conor.dooley@microchip.com>

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

[PATCH v2 3/4] dt-bindings: rtc: rzn1: add R-Car Gen5 support

[Wolfram Sang]

In general, the RTC on R-Car Gen5 is identical to RZ/T2H. X5H is an
exception, though, because interrupts are not wired. X5H2 will have them
wired again.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 .../bindings/rtc/renesas,rzn1-rtc.yaml        | 22 +++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
index 7ea77cd0bee1..186d0076590c 100644
--- a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
+++ b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
@@ -23,6 +23,11 @@ properties:
           - const: renesas,r9a09g087-rtc  # RZ/N2H
           - const: renesas,r9a09g077-rtc  # RZ/T2H
 
+      - items:
+          - enum:
+              - renesas,r8a78000-rtc      # R-Car X5H
+          - const: renesas,rcar-gen5-rtc  # R-Car Gen5
+
   reg:
     maxItems: 1
 
@@ -52,8 +57,6 @@ properties:
 required:
   - compatible
   - reg
-  - interrupts
-  - interrupt-names
   - clocks
   - clock-names
   - power-domains
@@ -68,6 +71,7 @@ allOf:
             enum:
               - renesas,r9a09g077-rtc
               - renesas,r9a09g087-rtc
+              - renesas,rcar-gen5-rtc
     then:
       properties:
         clocks:
@@ -75,6 +79,20 @@ allOf:
         clock-names:
           minItems: 2
 
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: renesas,r8a78000-rtc
+    then:
+      properties:
+        interrupts: false
+        interrupt-names: false
+    else:
+      required:
+        - interrupts
+        - interrupt-names
+
 unevaluatedProperties: false
 
 examples:
-- 
2.53.0

Re: [PATCH v2 3/4] dt-bindings: rtc: rzn1: add R-Car Gen5 support

[sashiko-bot]

> In general, the RTC on R-Car Gen5 is identical to RZ/T2H. X5H is an
> exception, though, because interrupts are not wired. X5H2 will have them
> wired again.
> 
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260916102520.24288-1-wsa+renesas@sang-engineering.com?part=3

Re: [PATCH v2 3/4] dt-bindings: rtc: rzn1: add R-Car Gen5 support

[Lad, Prabhakar]

On Wed, Sep 16, 2026 at 11:25 AM Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
>
> In general, the RTC on R-Car Gen5 is identical to RZ/T2H. X5H is an
> exception, though, because interrupts are not wired. X5H2 will have them
> wired again.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> ---
>  .../bindings/rtc/renesas,rzn1-rtc.yaml        | 22 +++++++++++++++++--
>  1 file changed, 20 insertions(+), 2 deletions(-)
>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Cheers,
Prabhakar

> diff --git a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> index 7ea77cd0bee1..186d0076590c 100644
> --- a/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> +++ b/Documentation/devicetree/bindings/rtc/renesas,rzn1-rtc.yaml
> @@ -23,6 +23,11 @@ properties:
>            - const: renesas,r9a09g087-rtc  # RZ/N2H
>            - const: renesas,r9a09g077-rtc  # RZ/T2H
>
> +      - items:
> +          - enum:
> +              - renesas,r8a78000-rtc      # R-Car X5H
> +          - const: renesas,rcar-gen5-rtc  # R-Car Gen5
> +
>    reg:
>      maxItems: 1
>
> @@ -52,8 +57,6 @@ properties:
>  required:
>    - compatible
>    - reg
> -  - interrupts
> -  - interrupt-names
>    - clocks
>    - clock-names
>    - power-domains
> @@ -68,6 +71,7 @@ allOf:
>              enum:
>                - renesas,r9a09g077-rtc
>                - renesas,r9a09g087-rtc
> +              - renesas,rcar-gen5-rtc
>      then:
>        properties:
>          clocks:
> @@ -75,6 +79,20 @@ allOf:
>          clock-names:
>            minItems: 2
>
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: renesas,r8a78000-rtc
> +    then:
> +      properties:
> +        interrupts: false
> +        interrupt-names: false
> +    else:
> +      required:
> +        - interrupts
> +        - interrupt-names
> +
>  unevaluatedProperties: false
>
>  examples:
> --
> 2.53.0
>

Re: [PATCH v2 3/4] dt-bindings: rtc: rzn1: add R-Car Gen5 support

[Geert Uytterhoeven]

On Wed, 16 Sept 2026 at 12:25, Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
> In general, the RTC on R-Car Gen5 is identical to RZ/T2H. X5H is an
> exception, though, because interrupts are not wired. X5H2 will have them
> wired again.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v2 3/4] dt-bindings: rtc: rzn1: add R-Car Gen5 support

[Rob Herring (Arm)]

On Wed, 16 Sep 2026 12:25:18 +0200, Wolfram Sang wrote:
> In general, the RTC on R-Car Gen5 is identical to RZ/T2H. X5H is an
> exception, though, because interrupts are not wired. X5H2 will have them
> wired again.
> 
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> ---
>  .../bindings/rtc/renesas,rzn1-rtc.yaml        | 22 +++++++++++++++++--
>  1 file changed, 20 insertions(+), 2 deletions(-)
> 

Acked-by: Rob Herring (Arm) <robh@kernel.org>

Re: [PATCH v2 0/4] rtc: rzn1: cleanups, R-Car Gen5 enablement

[Wolfram Sang]

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> Looking forward to comments.

Wow, Sashiko is happy and did not find any pre-existing issues? I am
amazed...

Anyhow, I wanted to repeat my thanks to previous reviewers. I think this
outcome is in deed cleaner and easier to understand / maintain.


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