Re: [PATCH v2 2/5] irqchip: sifive: Support hierarchy irq domain

From: Marc Zyngier <maz@kernel.org>
To: Yash Shah <yash.shah@sifive.com>
Cc: <linus.walleij@linaro.org>, <bgolaszewski@baylibre.com>,
	<robh+dt@kernel.org>, <mark.rutland@arm.com>,
	<palmer@dabbelt.com>,
	"Paul Walmsley ( Sifive)" <paul.walmsley@sifive.com>,
	<aou@eecs.berkeley.edu>, <tglx@linutronix.de>,
	<jason@lakedaemon.net>, <bmeng.cn@gmail.com>,
	<atish.patra@wdc.com>, Sagar Kadam <sagar.kadam@sifive.com>,
	<linux-gpio@vger.kernel.org>, <devicetree@vger.kernel.org>,
	<linux-riscv@lists.infradead.org>, <linux-kernel@vger.kernel.org>,
	Sachin Ghadi <sachin.ghadi@sifive.com>
Subject: Re: [PATCH v2 2/5] irqchip: sifive: Support hierarchy irq domain
Date: Fri, 22 Nov 2019 10:17:05 +0000	[thread overview]
Message-ID: <6bc97c77172ac277e0c28f68eb1ca440@www.loen.fr> (raw)
In-Reply-To: <1574233128-28114-3-git-send-email-yash.shah@sifive.com>

On 2019-11-20 06:59, Yash Shah wrote:
> Add support for hierarchy irq domains. This is needed as 
> pre-requisite for
> gpio-sifive driver.
>
> Signed-off-by: Yash Shah <yash.shah@sifive.com>
> ---
>  drivers/irqchip/Kconfig           |  1 +
>  drivers/irqchip/irq-sifive-plic.c | 30 
> ++++++++++++++++++++++++++----
>  2 files changed, 27 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
> index ccbb897..a398552 100644
> --- a/drivers/irqchip/Kconfig
> +++ b/drivers/irqchip/Kconfig
> @@ -488,6 +488,7 @@ endmenu
>  config SIFIVE_PLIC
>  	bool "SiFive Platform-Level Interrupt Controller"
>  	depends on RISCV
> +	select IRQ_DOMAIN_HIERARCHY
>  	help
>  	   This enables support for the PLIC chip found in SiFive (and
>  	   potentially other) RISC-V systems.  The PLIC controls devices
> diff --git a/drivers/irqchip/irq-sifive-plic.c
> b/drivers/irqchip/irq-sifive-plic.c
> index 7d0a12f..750e366 100644
> --- a/drivers/irqchip/irq-sifive-plic.c
> +++ b/drivers/irqchip/irq-sifive-plic.c
> @@ -154,15 +154,37 @@ static struct irq_chip plic_chip = {
>  static int plic_irqdomain_map(struct irq_domain *d, unsigned int 
> irq,
>  			      irq_hw_number_t hwirq)
>  {
> -	irq_set_chip_and_handler(irq, &plic_chip, handle_fasteoi_irq);
> -	irq_set_chip_data(irq, NULL);
> +	irq_domain_set_info(d, irq, hwirq, &plic_chip, d->host_data,
> +			    handle_fasteoi_irq, NULL, NULL);
>  	irq_set_noprobe(irq);
>  	return 0;
>  }
>
> +static int plic_irq_domain_alloc(struct irq_domain *domain, unsigned
> int virq,
> +				 unsigned int nr_irqs, void *arg)
> +{
> +	int i, ret;
> +	irq_hw_number_t hwirq;
> +	unsigned int type = IRQ_TYPE_NONE;

You shouldn't need this init here. The whole point of 
irq_domain_translate_onecell
is that it either gives you a valid value, or an error.

> +	struct irq_fwspec *fwspec = arg;
> +
> +	ret = irq_domain_translate_onecell(domain, fwspec, &hwirq, &type);
> +	if (ret)
> +		return ret;
> +
> +	for (i = 0; i < nr_irqs; i++) {
> +		ret = plic_irqdomain_map(domain, virq + i, hwirq + i);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> +
>  static const struct irq_domain_ops plic_irqdomain_ops = {
> -	.map		= plic_irqdomain_map,
> -	.xlate		= irq_domain_xlate_onecell,
> +	.translate	= irq_domain_translate_onecell,
> +	.alloc		= plic_irq_domain_alloc,
> +	.free		= irq_domain_free_irqs_top,
>  };
>
>  static struct irq_domain *plic_irqdomain;

Otherwise looks OK.

         M.
-- 
Jazz is not dead. It just smells funny...