[PATCH] irqchip/irq-gic-v3-its: Add the checking of ITS version for KVM

[Shaokun Zhang]

From: Wudi Wang <wangwudi@xxxxxxxxxxxxx>

The version of GIC used by KVM is provided by gic_v3_kvm_info.
The KVM that supports GICv4 or GICv4.1 only checks GIC
version. Actually, the GIC and ITS need to work together.
So we add the checking of ITS version for KVM: If and only if
both GIC & ITS support GICv4, gic_kvm_info.has_v4 is true.
If and only if both GIC & ITS support GICv4.1,
gic_kvm_info.has_v4_1 is true.

Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Marc Zyngier <maz@xxxxxxxxxx>
Signed-off-by: Wudi Wang <wangwudi@xxxxxxxxxxxxx>
Signed-off-by: Shaokun Zhang <zhangshaokun@xxxxxxxxxxxxx>
---
 drivers/irqchip/irq-gic-common.h |  2 ++
 drivers/irqchip/irq-gic-v3-its.c |  3 +++
 drivers/irqchip/irq-gic-v3.c     | 10 +++++-----
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/irqchip/irq-gic-common.h b/drivers/irqchip/irq-gic-common.h
index ccba8b0fe0f5..e5d44998445a 100644
--- a/drivers/irqchip/irq-gic-common.h
+++ b/drivers/irqchip/irq-gic-common.h
@@ -10,6 +10,8 @@
 #include <linux/irqdomain.h>
 #include <linux/irqchip/arm-gic-common.h>
 
+extern struct gic_kvm_info gic_v3_kvm_info;
+
 struct gic_quirk {
 	const char *desc;
 	const char *compatible;
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 2e6923c2c8a8..45d6163c14d5 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -5419,6 +5419,9 @@ int __init its_init(struct fwnode_handle *handle, struct rdists *rdists,
 		has_v4_1 |= is_v4_1(its);
 	}
 
+	gic_v3_kvm_info.has_v4 = has_v4;
+	gic_v3_kvm_info.has_v4_1 = has_v4_1;
+
 	/* Don't bother with inconsistent systems */
 	if (WARN_ON(!has_v4_1 && rdists->has_rvpeid))
 		rdists->has_rvpeid = false;
diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 37a23aa6de37..7454f99bf580 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -103,7 +103,7 @@ EXPORT_SYMBOL(gic_nonsecure_priorities);
 /* ppi_nmi_refs[n] == number of cpus having ppi[n + 16] set as NMI */
 static refcount_t *ppi_nmi_refs;
 
-static struct gic_kvm_info gic_v3_kvm_info;
+struct gic_kvm_info gic_v3_kvm_info;
 static DEFINE_PER_CPU(bool, has_rss);
 
 #define MPIDR_RS(mpidr)			(((mpidr) & 0xF0UL) >> 4)
@@ -1850,8 +1850,8 @@ static void __init gic_of_setup_kvm_info(struct device_node *node)
 	if (!ret)
 		gic_v3_kvm_info.vcpu = r;
 
-	gic_v3_kvm_info.has_v4 = gic_data.rdists.has_vlpis;
-	gic_v3_kvm_info.has_v4_1 = gic_data.rdists.has_rvpeid;
+	gic_v3_kvm_info.has_v4 &= gic_data.rdists.has_vlpis;
+	gic_v3_kvm_info.has_v4_1 &= gic_data.rdists.has_rvpeid;
 	gic_set_kvm_info(&gic_v3_kvm_info);
 }
 
@@ -2166,8 +2166,8 @@ static void __init gic_acpi_setup_kvm_info(void)
 		vcpu->end = vcpu->start + ACPI_GICV2_VCPU_MEM_SIZE - 1;
 	}
 
-	gic_v3_kvm_info.has_v4 = gic_data.rdists.has_vlpis;
-	gic_v3_kvm_info.has_v4_1 = gic_data.rdists.has_rvpeid;
+	gic_v3_kvm_info.has_v4 &= gic_data.rdists.has_vlpis;
+	gic_v3_kvm_info.has_v4_1 &= gic_data.rdists.has_rvpeid;
 	gic_set_kvm_info(&gic_v3_kvm_info);
 }
 
-- 
2.7.4