Re: [PATCH v3 3/4] irqchip: GIC: Convert to EOImode == 1

From: Marc Zyngier
Date: Tue Aug 25 2015 - 13:18:58 EST


Hi Thomas,

On 25/08/15 16:46, Thomas Gleixner wrote:
> On Tue, 25 Aug 2015, Marc Zyngier wrote:
>> +static struct static_key supports_deactivate = STATIC_KEY_INIT_TRUE;
>> +
>> #ifndef MAX_GIC_NR
>> #define MAX_GIC_NR 1
>> #endif
>> @@ -137,6 +140,14 @@ static inline unsigned int gic_irq(struct irq_data *d)
>> return d->hwirq;
>> }
>>
>> +static inline bool primary_gic_irq(struct irq_data *d)
>> +{
>> + if (MAX_GIC_NR > 1)
>> + return irq_data_get_irq_chip_data(d) == &gic_data[0];
>> +
>> + return true;
>> +}
>> +
>> /*
>> * Routines to acknowledge, disable and enable interrupts
>> */
>> @@ -164,7 +175,14 @@ static void gic_unmask_irq(struct irq_data *d)
>>
>> static void gic_eoi_irq(struct irq_data *d)
>> {
>> - writel_relaxed(gic_irq(d), gic_cpu_base(d) + GIC_CPU_EOI);
>> + u32 deact_offset = GIC_CPU_EOI;
>> +
>> + if (static_key_true(&supports_deactivate)) {
>> + if (primary_gic_irq(d))
>> + deact_offset = GIC_CPU_DEACTIVATE;
>
> I really wonder for the whole series whether you really want all that
> static key dance and extra conditionals in the callbacks instead of
> just using seperate irq chips for the different interrupts.

Hmmm. We definitely could have different irqchips between primary and
secondary controllers indeed. We'd still need a static key for the
gic_handle_irq path though, but that's not too bad.

Let me hack something, and I'll come back to you ;-).

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