[PATCH 07/10] PCI: dwc: Add support to use non default msi_irq_chip

[Kishon Vijay Abraham I]

Platforms using Designware IP uses dw_pci_msi_bottom_irq_chip for
configuring the MSI controller logic within the Designware IP. However
certain platforms like Keystone (K2G) which uses Desingware IP has
it's own MSI controller logic. For handling such platforms,
the irqchip ops uses msi_irq_ack, msi_set_irq, msi_clear_irq callback
functions.

Add support to use different msi_irq_chip with default as
dw_pci_msi_bottom_irq_chip. This is in preparation to get rid off
msi_irq_ack, msi_set_irq, msi_clear_irq and other Keystone specific
dw_pcie_host_ops.

Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
---
 drivers/pci/controller/dwc/pcie-designware-host.c | 5 ++++-
 drivers/pci/controller/dwc/pcie-designware.h      | 1 +
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 0fa9e8fdce66..db21bd11f153 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -245,7 +245,7 @@ static int dw_pcie_irq_domain_alloc(struct irq_domain *domain,
 
 	for (i = 0; i < nr_irqs; i++)
 		irq_domain_set_info(domain, virq + i, bit + i,
-				    &dw_pci_msi_bottom_irq_chip,
+				    pp->msi_irq_chip,
 				    pp, handle_edge_irq,
 				    NULL, NULL);
 
@@ -277,6 +277,9 @@ int dw_pcie_allocate_domains(struct pcie_port *pp)
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
 	struct fwnode_handle *fwnode = of_node_to_fwnode(pci->dev->of_node);
 
+	if (!pp->msi_irq_chip)
+		pp->msi_irq_chip = &dw_pci_msi_bottom_irq_chip;
+
 	pp->irq_domain = irq_domain_create_linear(fwnode, pp->num_vectors,
 					       &dw_pcie_msi_domain_ops, pp);
 	if (!pp->irq_domain) {
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 0989d880ac46..0873ee4084aa 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -168,6 +168,7 @@ struct pcie_port {
 	struct irq_domain	*irq_domain;
 	struct irq_domain	*msi_domain;
 	dma_addr_t		msi_data;
+	struct irq_chip		*msi_irq_chip;
 	u32			num_vectors;
 	u32			irq_status[MAX_MSI_CTRLS];
 	raw_spinlock_t		lock;
-- 
2.17.1