Merge branch 'pci/controller/dwc'

- Fall back to allocating 64-bit MSI DMA address if unable to allocate a
  32-bit address (Ajay Agarwal)

* pci/controller/dwc:
  PCI: dwc: endpoint: Fix advertised resizable BAR size
  PCI: dwc: Strengthen the MSI address allocation logic

2 files changed, 19 insertions, 9 deletions

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 5befed2dc02b..389daebc4316 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -627,8 +627,13 @@ int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep)
 		nbars = (reg & PCI_REBAR_CTRL_NBAR_MASK) >>
 			PCI_REBAR_CTRL_NBAR_SHIFT;
 
+		/*
+		 * PCIe r6.0, sec 7.8.6.2 require us to support at least one
+		 * size in the range from 1 MB to 512 GB. Advertise support
+		 * for 1 MB BAR size only.
+		 */
 		for (i = 0; i < nbars; i++, offset += PCI_REBAR_CTRL)
-			dw_pcie_writel_dbi(pci, offset + PCI_REBAR_CAP, 0x0);
+			dw_pcie_writel_dbi(pci, offset + PCI_REBAR_CAP, BIT(4));
 	}
 
 	/*
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index d5fc31f8345f..d15a5c2d5b48 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -328,7 +328,7 @@ static int dw_pcie_msi_host_init(struct dw_pcie_rp *pp)
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
 	struct device *dev = pci->dev;
 	struct platform_device *pdev = to_platform_device(dev);
-	u64 *msi_vaddr;
+	u64 *msi_vaddr = NULL;
 	int ret;
 	u32 ctrl, num_ctrls;
 
@@ -379,15 +379,20 @@ static int dw_pcie_msi_host_init(struct dw_pcie_rp *pp)
 	 * memory.
 	 */
 	ret = dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
-	if (ret)
-		dev_warn(dev, "Failed to set DMA mask to 32-bit. Devices with only 32-bit MSI support may not work properly\n");
+	if (!ret)
+		msi_vaddr = dmam_alloc_coherent(dev, sizeof(u64), &pp->msi_data,
+						GFP_KERNEL);
 
-	msi_vaddr = dmam_alloc_coherent(dev, sizeof(u64), &pp->msi_data,
-					GFP_KERNEL);
 	if (!msi_vaddr) {
-		dev_err(dev, "Failed to alloc and map MSI data\n");
-		dw_pcie_free_msi(pp);
-		return -ENOMEM;
+		dev_warn(dev, "Failed to allocate 32-bit MSI address\n");
+		dma_set_coherent_mask(dev, DMA_BIT_MASK(64));
+		msi_vaddr = dmam_alloc_coherent(dev, sizeof(u64), &pp->msi_data,
+						GFP_KERNEL);
+		if (!msi_vaddr) {
+			dev_err(dev, "Failed to allocate MSI address\n");
+			dw_pcie_free_msi(pp);
+			return -ENOMEM;
+		}
 	}
 
 	return 0;