2 files changed, 49 insertions, 0 deletions

diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index ffb84604c1de..bc2f5719dace 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -183,6 +183,12 @@ enum {
         /* Irq domain is an IPI domain with single virq */
         IRQ_DOMAIN_FLAG_IPI_SINGLE      = (1 << 3),
 
+        /* Irq domain implements MSIs */
+        IRQ_DOMAIN_FLAG_MSI             = (1 << 4),
+
+        /* Irq domain implements MSI remapping */
+        IRQ_DOMAIN_FLAG_MSI_REMAP       = (1 << 5),
+
         /*
          * Flags starting from IRQ_DOMAIN_FLAG_NONCORE are reserved
          * for implementation specific purposes and ignored by the
@@ -446,6 +452,19 @@ static inline bool irq_domain_is_ipi_single(struct irq_domain *domain)
 {
         return domain->flags & IRQ_DOMAIN_FLAG_IPI_SINGLE;
 }
+
+static inline bool irq_domain_is_msi(struct irq_domain *domain)
+{
+        return domain->flags & IRQ_DOMAIN_FLAG_MSI;
+}
+
+static inline bool irq_domain_is_msi_remap(struct irq_domain *domain)
+{
+        return domain->flags & IRQ_DOMAIN_FLAG_MSI_REMAP;
+}
+
+extern bool irq_domain_hierarchical_is_msi_remap(struct irq_domain *domain);
+
 #else   /* CONFIG_IRQ_DOMAIN_HIERARCHY */
 static inline void irq_domain_activate_irq(struct irq_data *data) { }
 static inline void irq_domain_deactivate_irq(struct irq_data *data) { }
@@ -477,6 +496,22 @@ static inline bool irq_domain_is_ipi_single(struct irq_domain *domain)
 {
         return false;
 }
+
+static inline bool irq_domain_is_msi(struct irq_domain *domain)
+{
+        return false;
+}
+
+static inline bool irq_domain_is_msi_remap(struct irq_domain *domain)
+{
+        return false;
+}
+
+static inline bool
+irq_domain_hierarchical_is_msi_remap(struct irq_domain *domain)
+{
+        return false;
+}
 #endif  /* CONFIG_IRQ_DOMAIN_HIERARCHY */
 
 #else /* CONFIG_IRQ_DOMAIN */
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 8c0a0ae43521..876e13172dc8 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -1392,6 +1392,20 @@ static void irq_domain_check_hierarchy(struct irq_domain *domain)
         if (domain->ops->alloc)
                 domain->flags |= IRQ_DOMAIN_FLAG_HIERARCHY;
 }
+
+/**
+ * irq_domain_hierarchical_is_msi_remap - Check if the domain or any
+ * parent has MSI remapping support
+ * @domain: domain pointer
+ */
+bool irq_domain_hierarchical_is_msi_remap(struct irq_domain *domain)
+{
+        for (; domain; domain = domain->parent) {
+                if (irq_domain_is_msi_remap(domain))
+                        return true;
+        }
+        return false;
+}
 #else   /* CONFIG_IRQ_DOMAIN_HIERARCHY */
 /**
  * irq_domain_get_irq_data - Get irq_data associated with @virq and @domain