Re: [PATCH v2 1/2] irqchip: stm32: Optimizes and cleans up stm32-exti irq_domain

From: RadosÅaw Pietrzyk
Date: Fri Feb 23 2018 - 12:37:13 EST


I don't fully get it to be honest. If interrupt is pending it must
have been enabled (unmasked) and requires to be handled acked. It will
be acked by irq_chip.irq_ack handler within the edge handler.
Therefore this additional acking is meaningless.

2018-02-23 16:46 GMT+01:00 Ludovic BARRE <ludovic.barre@xxxxxx>:
> hi Radoslaw
>
> The gpio-keys tests it's now functional on H7, great.
> However the gpio-key test only the bank1 (like stm32f429).
> Like the H7 introduce the multi-bank management,
> we must perform complementary test.
>
> comment below about ack in handler
>
>
> On 02/23/2018 09:31 AM, Radoslaw Pietrzyk wrote:
>>
>> - discards setting handle_simple_irq handler for hierarchy interrupts
>> - removes acking in chained irq handler as this is done by
>> irq_chip itself inside handle_edge_irq
>> - removes unneeded irq_domain_ops.xlate callback
>>
>> Signed-off-by: Radoslaw Pietrzyk <radoslaw.pietrzyk@xxxxxxxxx>
>> ---
>> drivers/irqchip/irq-stm32-exti.c | 13 -------------
>> 1 file changed, 13 deletions(-)
>>
>> diff --git a/drivers/irqchip/irq-stm32-exti.c
>> b/drivers/irqchip/irq-stm32-exti.c
>> index 36f0fbe..8013a87 100644
>> --- a/drivers/irqchip/irq-stm32-exti.c
>> +++ b/drivers/irqchip/irq-stm32-exti.c
>> @@ -79,13 +79,6 @@ static unsigned long stm32_exti_pending(struct
>> irq_chip_generic *gc)
>> return irq_reg_readl(gc, stm32_bank->pr_ofst);
>> }
>> -static void stm32_exti_irq_ack(struct irq_chip_generic *gc, u32 mask)
>> -{
>> - const struct stm32_exti_bank *stm32_bank = gc->private;
>> -
>> - irq_reg_writel(gc, mask, stm32_bank->pr_ofst);
>> -}
>> -
>> static void stm32_irq_handler(struct irq_desc *desc)
>> {
>> struct irq_domain *domain = irq_desc_get_handler_data(desc);
>> @@ -106,7 +99,6 @@ static void stm32_irq_handler(struct irq_desc *desc)
>> for_each_set_bit(n, &pending, IRQS_PER_BANK) {
>> virq = irq_find_mapping(domain, irq_base +
>> n);
>> generic_handle_irq(virq);
>> - stm32_exti_irq_ack(gc, BIT(n));
>
>
> the while loop " while ((pending = " has been introduce while original
> upstream of this driver in V2 to V3
> https://patchwork.ozlabs.org/patch/604190/
> https://patchwork.ozlabs.org/patch/665242/
>
> the "ack" is needed to acknowledge the irq which are handled and which is
> not the original irq for which we enter.
>
>> }
>> }
>> }
>> @@ -176,16 +168,12 @@ static int stm32_irq_set_wake(struct irq_data *data,
>> unsigned int on)
>> static int stm32_exti_alloc(struct irq_domain *d, unsigned int virq,
>> unsigned int nr_irqs, void *data)
>> {
>> - struct irq_chip_generic *gc;
>> struct irq_fwspec *fwspec = data;
>> irq_hw_number_t hwirq;
>> hwirq = fwspec->param[0];
>> - gc = irq_get_domain_generic_chip(d, hwirq);
>> irq_map_generic_chip(d, virq, hwirq);
>> - irq_domain_set_info(d, virq, hwirq, &gc->chip_types->chip, gc,
>> - handle_simple_irq, NULL, NULL);
>
>
> I see if it is not disturb the multi-bank.
>
>> return 0;
>> }
>> @@ -200,7 +188,6 @@ static void stm32_exti_free(struct irq_domain *d,
>> unsigned int virq,
>> struct irq_domain_ops irq_exti_domain_ops = {
>> .map = irq_map_generic_chip,
>> - .xlate = irq_domain_xlate_onetwocell,
>> .alloc = stm32_exti_alloc,
>> .free = stm32_exti_free,
>> };
>>
>
> BR
> Ludo