Re: [PATCH 1/3] dt-bindings: soc: renesas: add MFIS binding documentation

Geert Uytterhoeven
2026-03-19T08:59:02Z

Hi Wolfram,

On Tue, 17 Mar 2026 at 14:06, Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
> Add device tree bindings for the Renesas Multifunctional Interface
> (MFIS) as found on the Renesas R-Car X5H (r8a78000) SoC. MFIS includes
> features like Mailbox/HW Spinlock/Product Register.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Thanks for your patch!

> --- /dev/null
> +++ b/Documentation/devicetree/bindings/soc/renesas/renesas,r8a78000-mfis.yaml
> @@ -0,0 +1,160 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/soc/renesas/renesas,r8a78000-mfis.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Renesas MFIS (Multifunctional Interface) controller
> +
> +maintainers:
> + - Wolfram Sang <wsa+renesas@sang-engineering.com>
> +
> +description:
> + Renesas Multifunctional Interface (MFIS) provides functionality for

The Renesas Multifunctional Interface ...

> + communication between different CPU cores. Those cores can be in various
> + domains like AP, RT, or SCP. Functionality includes features like
> + mailboxes, hardware spinlocks and such.
> +
> +properties:
> + compatible:
> + enum:
> + - renesas,r8a78000-mfis # R-Car X5H (AP<->AP, with PRR)
> + - renesas,r8a78000-mfis-scp # R-Car X5H (AP<->SCP, without PRR)

[...]

> + interrupts:
> + minItems: 32
> + maxItems: 128
> + description:
> + The interrupts raised by the remote doorbells.
> +
> + interrupt-names:
> + minItems: 32
> + maxItems: 128
> + items:
> + pattern: "^ch[0-9]+[ie]$"
> + description:
> + An interrupt name is constructed with the prefix 'ch'. Then, the
> + channel number as specified in the documentation of the SoC. Finally,
> + the letter 'i' if the interrupt is raised by the IICR register. Or 'e'
> + if it is raised by the EICR register.

maxItems could be moved to a conditional schema, based on the compatible
value.
The same is true for the pattern rule, as MFIS has both "i" and "e"
interrupts, while MFIS-SCP has only the "i" variants.

> --- /dev/null
> +++ b/include/dt-bindings/mailbox/renesas,r8a78000-mfis.h
> @@ -0,0 +1,27 @@
> +/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
> +/*
> + * Constants for the mailbox part of the Renesas MFIS IP core.
> + */
> +
> +#ifndef _DT_BINDINGS_MAILBOX_RENESAS_MFIS_H
> +#define _DT_BINDINGS_MAILBOX_RENESAS_MFIS_H

The include protection does not match the filename.

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