Re: [PATCH 2/2] regmap: Allow setting IRQ domain name suffix

[Matti Vaittinen <mazziesaccount@gmail.com>]

On 7/13/24 15:22, Thomas Gleixner wrote:
> Matti!
> 
> On Mon, Jul 08 2024 at 15:40, Matti Vaittinen wrote:
>> On 7/7/24 21:13, Thomas Gleixner wrote:
>>>
>>> I wonder whether this can be handled at the core. Let me stare at it.
>>
>> Thanks Thomas! I'll wait for your ideas before re-spinning this series :)
> 
> Something like the untested below should work.

Thanks Thomas!

Sorry for a very late reply. I have tried to minimize my "computer time" 
during the last 1.5 months (I really needed a break) - but now I'm 
getting back to the business...

I used your patch below with the BD96801 driver and tested the changes 
to the extent that the IRQ domains were successfully created and names 
and numbers seemed reasonable. (I didn't yet try to make the PMIC to do 
a real IRQ though although it should be doable using the WDG.)

Do you want me to include this in my series (keeping you as author), or 
do you prefer going through the patch process yourself?

Yours,
	-- Matti

> ---
> --- a/include/linux/irqdomain.h
> +++ b/include/linux/irqdomain.h
> @@ -291,6 +291,9 @@ struct irq_domain_chip_generic_info;
>    * @hwirq_max:		Maximum number of interrupts supported by controller
>    * @direct_max:		Maximum value of direct maps;
>    *			Use ~0 for no limit; 0 for no direct mapping
> + * @hwirq_base:		The first hardware interrupt number (legacy domains only)
> + * @virq_base:		The first Linux interrupt number for legacy domains to
> + *			immediately associate the interrupts after domain creation
>    * @bus_token:		Domain bus token
>    * @ops:		Domain operation callbacks
>    * @host_data:		Controller private data pointer
> @@ -307,6 +310,8 @@ struct irq_domain_info {
>   	unsigned int				size;
>   	irq_hw_number_t				hwirq_max;
>   	int					direct_max;
> +	unsigned int				hwirq_base;
> +	unsigned int				virq_base;
>   	enum irq_domain_bus_token		bus_token;
>   	const struct irq_domain_ops		*ops;
>   	void					*host_data;
> --- a/kernel/irq/irqdomain.c
> +++ b/kernel/irq/irqdomain.c
> @@ -267,13 +267,20 @@ static void irq_domain_free(struct irq_d
>   	kfree(domain);
>   }
>   
> -/**
> - * irq_domain_instantiate() - Instantiate a new irq domain data structure
> - * @info: Domain information pointer pointing to the information for this domain
> - *
> - * Return: A pointer to the instantiated irq domain or an ERR_PTR value.
> - */
> -struct irq_domain *irq_domain_instantiate(const struct irq_domain_info *info)
> +static void irq_domain_instantiate_descs(const struct irq_domain_info *info)
> +{
> +	if (!IS_ENABLED(CONFIG_SPARSE_IRQ))
> +		return;
> +
> +	if (irq_alloc_descs(info->virq_base, info->virq_base, info->size,
> +			    of_node_to_nid(to_of_node(info->fwnode))) < 0) {
> +		pr_info("Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
> +			info->virq_base);
> +	}
> +}
> +
> +static struct irq_domain *__irq_domain_instantiate(const struct irq_domain_info *info,
> +						   bool cond_alloc_descs)
>   {
>   	struct irq_domain *domain;
>   	int err;
> @@ -306,6 +313,13 @@ struct irq_domain *irq_domain_instantiat
>   
>   	__irq_domain_publish(domain);
>   
> +	if (cond_alloc_descs && info->virq_base > 0)
> +		irq_domain_instantiate_descs(info);
> +
> +	/* Legacy interrupt domains have a fixed Linux interrupt number */
> +	if (info->virq_base > 0)
> +		irq_domain_associate_many(domain, info->virq_base, info->hwirq_base, info->size);
> +
>   	return domain;
>   
>   err_domain_gc_remove:
> @@ -315,6 +329,17 @@ struct irq_domain *irq_domain_instantiat
>   	irq_domain_free(domain);
>   	return ERR_PTR(err);
>   }
> +
> +/**
> + * irq_domain_instantiate() - Instantiate a new irq domain data structure
> + * @info: Domain information pointer pointing to the information for this domain
> + *
> + * Return: A pointer to the instantiated irq domain or an ERR_PTR value.
> + */
> +struct irq_domain *irq_domain_instantiate(const struct irq_domain_info *info)
> +{
> +	return __irq_domain_instantiate(info, false);
> +}
>   EXPORT_SYMBOL_GPL(irq_domain_instantiate);
>   
>   /**
> @@ -413,28 +438,13 @@ struct irq_domain *irq_domain_create_sim
>   		.fwnode		= fwnode,
>   		.size		= size,
>   		.hwirq_max	= size,
> +		.virq_base	= first_irq,
>   		.ops		= ops,
>   		.host_data	= host_data,
>   	};
> -	struct irq_domain *domain;
> -
> -	domain = irq_domain_instantiate(&info);
> -	if (IS_ERR(domain))
> -		return NULL;
> -
> -	if (first_irq > 0) {
> -		if (IS_ENABLED(CONFIG_SPARSE_IRQ)) {
> -			/* attempt to allocated irq_descs */
> -			int rc = irq_alloc_descs(first_irq, first_irq, size,
> -						 of_node_to_nid(to_of_node(fwnode)));
> -			if (rc < 0)
> -				pr_info("Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
> -					first_irq);
> -		}
> -		irq_domain_associate_many(domain, first_irq, 0, size);
> -	}
> +	struct irq_domain *domain = __irq_domain_instantiate(&info, true);
>   
> -	return domain;
> +	return IS_ERR(domain) ? NULL : domain;
>   }
>   EXPORT_SYMBOL_GPL(irq_domain_create_simple);
>   
> @@ -476,18 +486,14 @@ struct irq_domain *irq_domain_create_leg
>   		.fwnode		= fwnode,
>   		.size		= first_hwirq + size,
>   		.hwirq_max	= first_hwirq + size,
> +		.hwirq_base	= first_hwirq,
> +		.virq_base	= first_irq,
>   		.ops		= ops,
>   		.host_data	= host_data,
>   	};
> -	struct irq_domain *domain;
> +	struct irq_domain *domain = irq_domain_instantiate(&info);
>   
> -	domain = irq_domain_instantiate(&info);
> -	if (IS_ERR(domain))
> -		return NULL;
> -
> -	irq_domain_associate_many(domain, first_irq, first_hwirq, size);
> -
> -	return domain;
> +	return IS_ERR(domain) ? NULL : domain;
>   }
>   EXPORT_SYMBOL_GPL(irq_domain_create_legacy);
>   

-- 
Matti Vaittinen
Linux kernel developer at ROHM Semiconductors
Oulu Finland

~~ When things go utterly wrong vim users can always type :help! ~~