[PATCH] irqchip/gic-v3: Pass GICV index to gic_of_setup_kvm_info()

[PATCH] irqchip/gic-v3: Pass GICV index to gic_of_setup_kvm_info()

[Geert Uytterhoeven]

The caller of gic_of_setup_kvm_info() already queried DT for the value
of the #redistributor-regions property.  So just calculate and pass the
GICV index, instead of doing the DT look-up again in the callee.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/irqchip/irq-gic-v3.c | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 1f70262742f3b7c7..9c03b63277ba5b2b 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -2185,11 +2185,10 @@ static void __init gic_populate_ppi_partitions(struct device_node *gic_node)
 	of_node_put(parts_node);
 }
 
-static void __init gic_of_setup_kvm_info(struct device_node *node)
+static void __init gic_of_setup_kvm_info(struct device_node *node, u32 gicv_idx)
 {
 	int ret;
 	struct resource r;
-	u32 gicv_idx;
 
 	gic_v3_kvm_info.type = GIC_V3;
 
@@ -2197,11 +2196,6 @@ static void __init gic_of_setup_kvm_info(struct device_node *node)
 	if (!gic_v3_kvm_info.maint_irq)
 		return;
 
-	if (of_property_read_u32(node, "#redistributor-regions",
-				 &gicv_idx))
-		gicv_idx = 1;
-
-	gicv_idx += 3;	/* Also skip GICD, GICC, GICH */
 	ret = of_address_to_resource(node, gicv_idx, &r);
 	if (!ret)
 		gic_v3_kvm_info.vcpu = r;
@@ -2292,7 +2286,7 @@ static int __init gic_of_init(struct device_node *node, struct device_node *pare
 	gic_populate_ppi_partitions(node);
 
 	if (static_branch_likely(&supports_deactivate_key))
-		gic_of_setup_kvm_info(node);
+		gic_of_setup_kvm_info(node, nr_redist_regions + 3);
 	return 0;
 
 out_unmap_rdist:
-- 
2.34.1

Re: [PATCH] irqchip/gic-v3: Pass GICV index to gic_of_setup_kvm_info()

[Marc Zyngier]

Hi Geert,

On Fri, 28 Jun 2024 13:23:29 +0100,
Geert Uytterhoeven <geert+renesas@glider.be> wrote:
> 
> The caller of gic_of_setup_kvm_info() already queried DT for the value
> of the #redistributor-regions property.  So just calculate and pass the
> GICV index, instead of doing the DT look-up again in the callee.
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
>  drivers/irqchip/irq-gic-v3.c | 10 ++--------
>  1 file changed, 2 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
> index 1f70262742f3b7c7..9c03b63277ba5b2b 100644
> --- a/drivers/irqchip/irq-gic-v3.c
> +++ b/drivers/irqchip/irq-gic-v3.c
> @@ -2185,11 +2185,10 @@ static void __init gic_populate_ppi_partitions(struct device_node *gic_node)
>  	of_node_put(parts_node);
>  }
>  
> -static void __init gic_of_setup_kvm_info(struct device_node *node)
> +static void __init gic_of_setup_kvm_info(struct device_node *node, u32 gicv_idx)
>  {
>  	int ret;
>  	struct resource r;
> -	u32 gicv_idx;
>  
>  	gic_v3_kvm_info.type = GIC_V3;
>  
> @@ -2197,11 +2196,6 @@ static void __init gic_of_setup_kvm_info(struct device_node *node)
>  	if (!gic_v3_kvm_info.maint_irq)
>  		return;
>  
> -	if (of_property_read_u32(node, "#redistributor-regions",
> -				 &gicv_idx))
> -		gicv_idx = 1;
> -
> -	gicv_idx += 3;	/* Also skip GICD, GICC, GICH */

Please keep the comment and/or make this '3' a #define so that we can
easily remember why we're adding some apparently random number.

>  	ret = of_address_to_resource(node, gicv_idx, &r);
>  	if (!ret)
>  		gic_v3_kvm_info.vcpu = r;
> @@ -2292,7 +2286,7 @@ static int __init gic_of_init(struct device_node *node, struct device_node *pare
>  	gic_populate_ppi_partitions(node);
>  
>  	if (static_branch_likely(&supports_deactivate_key))
> -		gic_of_setup_kvm_info(node);
> +		gic_of_setup_kvm_info(node, nr_redist_regions + 3);
>  	return 0;
>  
>  out_unmap_rdist:

With that fixed,

Acked-by: Marc Zyngier <maz@kernel.org>

	M.

-- 
Without deviation from the norm, progress is not possible.