[PATCH 2/4] irqchip/armada-370-xp: Exit ipi_resume() early if IPI is not used

[Andrew Lunn]

On Wed, Jun 19, 2024 at 04:11:32PM +0200, Marek Behún wrote:
> From: Pali Rohár <pali at kernel.org>
> 
> Exit ipi_resume() early if IPI is not used.
> 
> IPI is used only on systems where the mpic controller does not have a
> parent GIC IRQ (e.g. on Armada XP).
> 
> Signed-off-by: Pali Rohár <pali at kernel.org>
> [ changed commit message and moved the code change into ipi_resume() ]
> Signed-off-by: Marek Behún <kabel at kernel.org>
> ---
>  drivers/irqchip/irq-armada-370-xp.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/drivers/irqchip/irq-armada-370-xp.c b/drivers/irqchip/irq-armada-370-xp.c
> index f488c35d9130..65f21624263e 100644
> --- a/drivers/irqchip/irq-armada-370-xp.c
> +++ b/drivers/irqchip/irq-armada-370-xp.c
> @@ -29,6 +29,7 @@
>  #include <linux/slab.h>
>  #include <linux/syscore_ops.h>
>  #include <linux/msi.h>
> +#include <linux/types.h>
>  #include <asm/mach/arch.h>
>  #include <asm/exception.h>
>  #include <asm/smp_plat.h>
> @@ -156,6 +157,12 @@ static DEFINE_MUTEX(msi_used_lock);
>  static phys_addr_t msi_doorbell_addr;
>  #endif
>  
> +static inline bool is_ipi_available(void)
> +{
> +	/* IPI is used only if we do not have parent irq */
> +	return parent_irq <= 0;
> +}
> +
>  static inline bool is_percpu_irq(irq_hw_number_t irq)
>  {
>  	if (irq <= ARMADA_370_XP_MAX_PER_CPU_IRQS)
> @@ -429,6 +436,9 @@ static void ipi_resume(void)
>  {
>  	int i;
>  
> +	if (!is_ipi_available())
> +		return;

But of a nitpick, but it seems odd calling ipi_resume() if it does not
exist. I would prefer

       
	if (is_ipi_available())
		ipi_resume();

At the two places ipi_resume() is called.

   Andrew