Re: [PATCH 3/4] irqchip/gic: Use GIC_* DT binding definitions

From: Marc Zyngier <maz@kernel.org>
To: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Thomas Gleixner <tglx@kernel.org>, Rob Herring <robh@kernel.org>,
	Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>,
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	Florian Fainelli <florian.fainelli@broadcom.com>,
	Broadcom internal kernel review list
	<bcm-kernel-feedback-list@broadcom.com>,
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	Sascha Hauer <s.hauer@pengutronix.de>,
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Subject: Re: [PATCH 3/4] irqchip/gic: Use GIC_* DT binding definitions
Date: Thu, 05 Mar 2026 10:13:53 +0000	[thread overview]
Message-ID: <86v7fa7fdq.wl-maz@kernel.org> (raw)
In-Reply-To: <d22488d128d39fcd90359f59559fac637bb4b04c.1772644406.git.geert+renesas@glider.be>

On Wed, 04 Mar 2026 17:21:58 +0000,
Geert Uytterhoeven <geert+renesas@glider.be> wrote:
> 
> Replace magic numbers by symbolic DT binding definitions.  This improves
> readability, and makes it easier to find where the various GIC
> interrupts types are handled.
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
>  drivers/irqchip/irq-gic-v3.c | 14 ++++++++------
>  drivers/irqchip/irq-gic.c    |  6 ++++--
>  2 files changed, 12 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
> index d75163e71bf22473..6ac103cb40097acc 100644
> --- a/drivers/irqchip/irq-gic-v3.c
> +++ b/drivers/irqchip/irq-gic-v3.c
> @@ -35,6 +35,8 @@
>  #include <asm/smp_plat.h>
>  #include <asm/virt.h>
>  
> +#include <dt-bindings/interrupt-controller/arm-gic.h>
> +
>  #include "irq-gic-common.h"
>  
>  static u8 dist_prio_irq __ro_after_init = GICV3_PRIO_IRQ;
> @@ -1602,25 +1604,25 @@ static int gic_irq_domain_translate(struct irq_domain *d,
>  			return -EINVAL;
>  
>  		switch (fwspec->param[0]) {
> -		case 0:			/* SPI */
> +		case GIC_SPI:

I'd rather not do that. I use *numeric* values on purpose, because
that's what the DT *binding* describes, and I have no control over
what lives in that include file (it gets changed without me being even
Cc'd).

So I want to stick to the binding, and not to the interpretation of
it. If you want symbolic values to be used, describe them in the
binding, have a tool to generate the values from the binding, and use
that everywhere.

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.