From: Minghuan Lian <Minghuan.Lian@freescale.com>
Date: Fri, 16 Oct 2015 07:19:16 +0000 (+0800)
Subject: PCI: layerscape: Ignore PCIe controllers in Endpoint mode
X-Git-Tag: firefly_0821_release~176^2~768^2^2~5
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=7af4ce3571931bdc043c4220402262f817b9b968;p=firefly-linux-kernel-4.4.55.git

PCI: layerscape: Ignore PCIe controllers in Endpoint mode

Layerscape PCIe controller supports root complex (RC) and endpoint (EP)
modes, which can be set by RCW.

If not in RC mode, return -ENODEV without claiming the controller.

Signed-off-by: Minghuan Lian <Minghuan.Lian@freescale.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---

diff --git a/drivers/pci/host/pci-layerscape.c b/drivers/pci/host/pci-layerscape.c
index 6dd44a071240..5eabe9238f0e 100644
--- a/drivers/pci/host/pci-layerscape.c
+++ b/drivers/pci/host/pci-layerscape.c
@@ -47,6 +47,16 @@ struct ls_pcie {
 
 #define to_ls_pcie(x)	container_of(x, struct ls_pcie, pp)
 
+static bool ls_pcie_is_bridge(struct ls_pcie *pcie)
+{
+	u32 header_type;
+
+	header_type = ioread8(pcie->dbi + PCI_HEADER_TYPE);
+	header_type &= 0x7f;
+
+	return header_type == PCI_HEADER_TYPE_BRIDGE;
+}
+
 static int ls_pcie_link_up(struct pcie_port *pp)
 {
 	u32 state;
@@ -135,6 +145,9 @@ static int __init ls_pcie_probe(struct platform_device *pdev)
 		return ret;
 	pcie->index = index[1];
 
+	if (!ls_pcie_is_bridge(pcie))
+		return -ENODEV;
+
 	ret = ls_add_pcie_port(pcie);
 	if (ret < 0)
 		return ret;