PCI: cadence: Add MSI-X support to Endpoint driver

Implement ->set_msix() and ->get_msix() callback functions in order
to configure MSIX capability in the PCIe endpoint controller.

Add cdns_pcie_ep_send_msix_irq() to send MSIX interrupts to Host.
cdns_pcie_ep_send_msix_irq() gets the MSIX table address (virtual
address) from "struct cdns_pcie_epf" that gets initialized in
->set_bar() call back function.

[kishon@ti.com: Re-implement MSIX support in accordance with the
 re-designed core MSI-X interfaces]
Link: https://lore.kernel.org/r/20200722110317.4744-11-kishon@ti.com
Signed-off-by: Alan Douglas <adouglas@cadence.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
index 7c804ac1dbc2..dd910a1c30fb 100644
--- a/drivers/pci/controller/cadence/pcie-cadence.h
+++ b/drivers/pci/controller/cadence/pcie-cadence.h
@@ -113,6 +113,7 @@
 #define CDNS_PCIE_EP_FUNC_BASE(fn)	(((fn) << 12) & GENMASK(19, 12))
 
 #define CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET	0x90
+#define CDNS_PCIE_EP_FUNC_MSIX_CAP_OFFSET	0xb0
 
 /*
  * Root Port Registers (PCI configuration space for the root port function)
@@ -303,6 +304,14 @@ struct cdns_pcie_rc {
 };
 
 /**
+ * struct cdns_pcie_epf - Structure to hold info about endpoint function
+ * @epf_bar: reference to the pci_epf_bar for the six Base Address Registers
+ */
+struct cdns_pcie_epf {
+	struct pci_epf_bar *epf_bar[PCI_STD_NUM_BARS];
+};
+
+/**
  * struct cdns_pcie_ep - private data for this PCIe endpoint controller driver
  * @pcie: Cadence PCIe controller
  * @max_regions: maximum number of regions supported by hardware
@@ -321,6 +330,7 @@ struct cdns_pcie_rc {
  * @lock: spin lock to disable interrupts while modifying PCIe controller
  *        registers fields (RMW) accessible by both remote RC and EP to
  *        minimize time between read and write
+ * @epf: Structure to hold info about endpoint function
  */
 struct cdns_pcie_ep {
 	struct cdns_pcie	pcie;
@@ -334,6 +344,7 @@ struct cdns_pcie_ep {
 	u8			irq_pending;
 	/* protect writing to PCI_STATUS while raising legacy interrupts */
 	spinlock_t		lock;
+	struct cdns_pcie_epf	*epf;
 };