Commit 1ec38ce3 authored by Sascha Bischoff's avatar Sascha Bischoff Committed by Oliver Upton
Browse files

irqchip/gic-v5: Populate struct gic_kvm_info 



Populate the gic_kvm_info struct based on support for
FEAT_GCIE_LEGACY.  The struct is used by KVM to probe for a compatible
GIC.

Co-authored-by: default avatarTimothy Hayes <timothy.hayes@arm.com>
Signed-off-by: default avatarTimothy Hayes <timothy.hayes@arm.com>
Signed-off-by: default avatarSascha Bischoff <sascha.bischoff@arm.com>
Reviewed-by: default avatarLorenzo Pieralisi <lpieralisi@kernel.org>
Link: https://lore.kernel.org/r/20250627100847.1022515-3-sascha.bischoff@arm.com


Signed-off-by: default avatarOliver Upton <oliver.upton@linux.dev>
parent 244e9a89

drivers/irqchip/irq-gic-v5.c

+33 −0
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ 


#include <linux/irqchip.h>

#include <linux/irqchip/arm-gic-v5.h>

#include <linux/irqchip/arm-vgic-info.h>



#include <asm/cpufeature.h>

#include <asm/exception.h>
@@ -1058,6 +1059,36 @@ static void gicv5_set_cpuif_idbits(void) 
	}

}



#ifdef CONFIG_KVM

static struct gic_kvm_info gic_v5_kvm_info __initdata;



static bool __init gicv5_cpuif_has_gcie_legacy(void)

{

	u64 idr0 = read_sysreg_s(SYS_ICC_IDR0_EL1);

	return !!FIELD_GET(ICC_IDR0_EL1_GCIE_LEGACY, idr0);

}



static void __init gic_of_setup_kvm_info(struct device_node *node)

{

	gic_v5_kvm_info.type = GIC_V5;

	gic_v5_kvm_info.has_gcie_v3_compat = gicv5_cpuif_has_gcie_legacy();



	/* GIC Virtual CPU interface maintenance interrupt */

	gic_v5_kvm_info.no_maint_irq_mask = false;

	gic_v5_kvm_info.maint_irq = irq_of_parse_and_map(node, 0);

	if (!gic_v5_kvm_info.maint_irq) {

		pr_warn("cannot find GICv5 virtual CPU interface maintenance interrupt\n");

		return;

	}



	vgic_set_kvm_info(&gic_v5_kvm_info);

}

#else

static inline void __init gic_of_setup_kvm_info(struct device_node *node)

{

}

#endif // CONFIG_KVM



static int __init gicv5_of_init(struct device_node *node, struct device_node *parent)

{

	int ret = gicv5_irs_of_probe(node);
@@ -1090,6 +1121,8 @@ static int __init gicv5_of_init(struct device_node *node, struct device_node *pa 


	gicv5_irs_its_probe();



	gic_of_setup_kvm_info(node);



	return 0;



out_int:

include/linux/irqchip/arm-vgic-info.h

+4 −0
Original line number Diff line number Diff line
@@ -15,6 +15,8 @@ enum gic_type { 
	GIC_V2,

	/* Full GICv3, optionally with v2 compat */

	GIC_V3,

	/* Full GICv5, optionally with v3 compat */

	GIC_V5,

};



struct gic_kvm_info {
@@ -34,6 +36,8 @@ struct gic_kvm_info { 
	bool		has_v4_1;

	/* Deactivation impared, subpar stuff */

	bool		no_hw_deactivation;

	/* v3 compat support (GICv5 hosts, only) */

	bool		has_gcie_v3_compat;

};



#ifdef CONFIG_KVM