[PATCHv2] PCI: designware-ep: Fix the Header Type check

From: Zhiqiang Hou
Date: Tue Aug 18 2020 - 05:35:13 EST


From: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>

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

Fixes: 0b24134f7888 ("PCI: dwc: Add validation that PCIe core is set to correct mode")
Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
---
V2:
- Add marco PCI_HEADER_TYPE_MASK and print the masked value.

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 4680a51c49c0..0634bd3a0b96 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -653,7 +653,8 @@ 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 f9701410d3b5..57a222014cd2 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
--
2.17.1