Just like for vLPIs, there is some configuration information that cannot
be directly communicated through the normal irqchip API, and we have to
use our good old friend set_vcpu_affinity as a side-band communication
mechanism.

This is used to configure group and priority for a given vSGI.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
---
 drivers/irqchip/irq-gic-v3-its.c   | 18 ++++++++++++++++++
 include/linux/irqchip/arm-gic-v4.h |  5 +++++
 2 files changed, 23 insertions(+)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index fb2b836c31ff..effb0e0b0c9d 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c

@@ -4033,6 +4033,23 @@ static int its_sgi_get_irqchip_state(struct irq_data *d,
 	return 0;
 }
 
+static int its_sgi_set_vcpu_affinity(struct irq_data *d, void *vcpu_info)
+{
+	struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
+	struct its_cmd_info *info = vcpu_info;
+
+	switch (info->cmd_type) {
+	case PROP_UPDATE_SGI:

+	default:
+		return -EINVAL;
+	}
+}
+
 static struct irq_chip its_sgi_irq_chip = {
 	.name			= "GICv4.1-sgi",
 	.irq_mask		= its_sgi_mask_irq,

@@ -4040,6 +4057,7 @@ static struct irq_chip its_sgi_irq_chip = {
 	.irq_set_affinity	= its_sgi_set_affinity,
 	.irq_set_irqchip_state	= its_sgi_set_irqchip_state,
 	.irq_get_irqchip_state	= its_sgi_get_irqchip_state,
+	.irq_set_vcpu_affinity	= its_sgi_set_vcpu_affinity,
 };
 
 static int its_sgi_irq_domain_alloc(struct irq_domain *domain,

diff --git a/include/linux/irqchip/arm-gic-v4.h b/include/linux/irqchip/arm-gic-v4.h
index 44e8c19e3d56..b4dbf899460b 100644
--- a/include/linux/irqchip/arm-gic-v4.h
+++ b/include/linux/irqchip/arm-gic-v4.h

@@ -103,6 +103,7 @@ enum its_vcpu_info_cmd_type {
 	SCHEDULE_VPE,
 	DESCHEDULE_VPE,
 	INVALL_VPE,
+	PROP_UPDATE_SGI,
 };
 
 struct its_cmd_info {

@@ -115,6 +116,10 @@ struct its_cmd_info {
 			bool		g0en;
 			bool		g1en;
 		};
+		struct {
+			u8		priority;
+			bool		group;
+		};
 	};
 };