PCI: cadence: Implement ->msi_map_irq() ops

Implement ->msi_map_irq() ops in order to map physical address to MSI
address and return MSI data.

Link: https://lore.kernel.org/r/20210201195809.7342-12-kishon@ti.comSigned-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Tom Joseph <tjoseph@cadence.com>

drivers/pci/controller/cadence/pcie-cadence-ep.c

@@ -382,6 +382,57 @@ static int cdns_pcie_ep_send_msi_irq(struct cdns_pcie_ep *ep, u8 fn,
 	return 0;
 }
 
+static int cdns_pcie_ep_map_msi_irq(struct pci_epc *epc, u8 fn,
+				    phys_addr_t addr, u8 interrupt_num,
+				    u32 entry_size, u32 *msi_data,
+				    u32 *msi_addr_offset)
+{
+	struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
+	u32 cap = CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET;
+	struct cdns_pcie *pcie = &ep->pcie;
+	u64 pci_addr, pci_addr_mask = 0xff;
+	u16 flags, mme, data, data_mask;
+	u8 msi_count;
+	int ret;
+	int i;
+
+	/* Check whether the MSI feature has been enabled by the PCI host. */
+	flags = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_MSI_FLAGS);
+	if (!(flags & PCI_MSI_FLAGS_ENABLE))
+		return -EINVAL;
+
+	/* Get the number of enabled MSIs */
+	mme = (flags & PCI_MSI_FLAGS_QSIZE) >> 4;
+	msi_count = 1 << mme;
+	if (!interrupt_num || interrupt_num > msi_count)
+		return -EINVAL;
+
+	/* Compute the data value to be written. */
+	data_mask = msi_count - 1;
+	data = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_MSI_DATA_64);
+	data = data & ~data_mask;
+
+	/* Get the PCI address where to write the data into. */
+	pci_addr = cdns_pcie_ep_fn_readl(pcie, fn, cap + PCI_MSI_ADDRESS_HI);
+	pci_addr <<= 32;
+	pci_addr |= cdns_pcie_ep_fn_readl(pcie, fn, cap + PCI_MSI_ADDRESS_LO);
+	pci_addr &= GENMASK_ULL(63, 2);
+
+	for (i = 0; i < interrupt_num; i++) {
+		ret = cdns_pcie_ep_map_addr(epc, fn, addr,
+					    pci_addr & ~pci_addr_mask,
+					    entry_size);
+		if (ret)
+			return ret;
+		addr = addr + entry_size;
+	}
+
+	*msi_data = data;
+	*msi_addr_offset = pci_addr & pci_addr_mask;
+
+	return 0;
+}
+
 static int cdns_pcie_ep_send_msix_irq(struct cdns_pcie_ep *ep, u8 fn,
 				      u16 interrupt_num)
 {
@@ -481,6 +532,7 @@ static const struct pci_epc_features cdns_pcie_epc_features = {
 	.linkup_notifier = false,
 	.msi_capable = true,
 	.msix_capable = true,
+	.align = 256,
 };
 
 static const struct pci_epc_features*
@@ -500,6 +552,7 @@ static const struct pci_epc_ops cdns_pcie_epc_ops = {
 	.set_msix	= cdns_pcie_ep_set_msix,
 	.get_msix	= cdns_pcie_ep_get_msix,
 	.raise_irq	= cdns_pcie_ep_raise_irq,
+	.map_msi_irq	= cdns_pcie_ep_map_msi_irq,
 	.start		= cdns_pcie_ep_start,
 	.get_features	= cdns_pcie_ep_get_features,
 };