@@ -189,6 +189,9 @@ enum {
/* Irq domain doesn't translate anything */
IRQ_DOMAIN_FLAG_NO_MAP = (1 << 6),
+ /* Irq domain is a MSI parent domain */
+ IRQ_DOMAIN_FLAG_MSI_PARENT = (1 << 8),
+
/*
* Flags starting from IRQ_DOMAIN_FLAG_NONCORE are reserved
* for implementation specific purposes and ignored by the
@@ -551,6 +554,11 @@ static inline bool irq_domain_is_msi_rem
extern bool irq_domain_hierarchical_is_msi_remap(struct irq_domain *domain);
+static inline bool irq_domain_is_msi_parent(struct irq_domain *domain)
+{
+ return domain->flags & IRQ_DOMAIN_FLAG_MSI_PARENT;
+}
+
#else /* CONFIG_IRQ_DOMAIN_HIERARCHY */
static inline int irq_domain_alloc_irqs(struct irq_domain *domain,
unsigned int nr_irqs, int node, void *arg)
@@ -596,6 +604,12 @@ irq_domain_hierarchical_is_msi_remap(str
{
return false;
}
+
+static inline bool irq_domain_is_msi_parent(struct irq_domain *domain)
+{
+ return false;
+}
+
#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
#else /* CONFIG_IRQ_DOMAIN */
The new PCI/IMS (Interrupt Message Store) functionality is allowing hardware vendors to provide implementation specific storage for the MSI messages. This can be device memory and also host/guest memory, e.g. in queue memory which is shared with the hardware. This requires device specific MSI interrupt domains, which cannot be achieved by expanding the existing PCI/MSI interrupt domain concept which is a global interrupt domain shared by all PCI devices on a particular (IOMMU) segment: |--- device 1 [Vector]---[Remapping]---[PCI/MSI]--|... |--- device N This works because the PCI/MSI[-X] space is uniform, but falls apart with PCI/IMS which is implementation defined and must be available along with PCI/MSI[-X] on the same device. To support PCI/MSI[-X] plus PCI/IMS on the same device it is required to rework the PCI/MSI interrupt domain hierarchy concept in the following way: |--- [PCI/MSI] device 1 [Vector]---[Remapping]---|... |--- [PCI/MSI] device N That allows in the next step to create multiple interrupt domains per device: |--- [PCI/MSI] device 1 |--- [PCI/IMS] device 1 [Vector]---[Remapping]---|... |--- [PCI/MSI] device N |--- [PCI/IMS] device N So the domain which previously created the global PCI/MSI domain must now act as parent domain for the per device domains. The hierarchy depth is the same as before, but the PCI/MSI domains are then device specific and not longer global. Provide IRQ_DOMAIN_FLAG_MSI_PARENT, which allows to identify these parent domains, along with helpers to query it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> --- include/linux/irqdomain.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+)