[PATCH 5.8 429/633] PCI: designware-ep: Fix the Header Type check

[Greg Kroah-Hartman]

From: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>

[ Upstream commit 16270a92355722e387e9ca19627c5a4d7bae1354 ]

The current check will result in the multiple function device
fails to initialize. So fix the check by masking out the
multiple function bit.

Link: https://lore.kernel.org/r/20200818092746.24366-1-Zhiqiang.Hou@xxxxxxx
Fixes: 0b24134f7888 ("PCI: dwc: Add validation that PCIe core is set to correct mode")
Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/pci/controller/dwc/pcie-designware-ep.c | 3 ++-
 include/uapi/linux/pci_regs.h                   | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 5e5b8821bed8c..ce1c00ea5fdca 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -505,7 +505,8 @@ int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep)
 	u32 reg;
 	int i;
 
-	hdr_type = dw_pcie_readb_dbi(pci, PCI_HEADER_TYPE);
+	hdr_type = dw_pcie_readb_dbi(pci, PCI_HEADER_TYPE) &
+		   PCI_HEADER_TYPE_MASK;
 	if (hdr_type != PCI_HEADER_TYPE_NORMAL) {
 		dev_err(pci->dev,
 			"PCIe controller is not set to EP mode (hdr_type:0x%x)!\n",
diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
index f9701410d3b52..57a222014cd20 100644
--- a/include/uapi/linux/pci_regs.h
+++ b/include/uapi/linux/pci_regs.h
@@ -76,6 +76,7 @@
 #define PCI_CACHE_LINE_SIZE	0x0c	/* 8 bits */
 #define PCI_LATENCY_TIMER	0x0d	/* 8 bits */
 #define PCI_HEADER_TYPE		0x0e	/* 8 bits */
+#define  PCI_HEADER_TYPE_MASK		0x7f
 #define  PCI_HEADER_TYPE_NORMAL		0
 #define  PCI_HEADER_TYPE_BRIDGE		1
 #define  PCI_HEADER_TYPE_CARDBUS	2
-- 
2.25.1