[PATCH 1/3] PCI: dwc: Add support for vendor specific capability search

[Shradha Todi]

Add vendor specific extended configuration space capability search API
using struct dw_pcie pointer for DW controllers.

Signed-off-by: Shradha Todi <shradha.t@xxxxxxxxxxx>
---
 drivers/pci/controller/dwc/pcie-designware.c | 16 ++++++++++++++++
 drivers/pci/controller/dwc/pcie-designware.h |  4 ++++
 2 files changed, 20 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index a945f0c0e73d..348f6f696976 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -90,6 +90,22 @@ static u16 dw_pcie_find_next_ext_capability(struct dw_pcie *pci, u16 start,
 	return 0;
 }
 
+u16 dw_pcie_find_vsec_capability(struct dw_pcie *pci, u8 vsec_cap)
+{
+	u16 vsec = 0;
+	u32 header;
+
+	while ((vsec = dw_pcie_find_next_ext_capability(pci, vsec,
+					PCI_EXT_CAP_ID_VNDR))) {
+		header = dw_pcie_readl_dbi(pci, vsec + PCI_VNDR_HEADER);
+		if (PCI_VNDR_HEADER_ID(header) == vsec_cap)
+			return vsec;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dw_pcie_find_vsec_capability);
+
 u16 dw_pcie_find_ext_capability(struct dw_pcie *pci, u8 cap)
 {
 	return dw_pcie_find_next_ext_capability(pci, 0, cap);
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 7d6e9b7576be..307525aaa063 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -155,6 +155,9 @@
 #define MAX_IATU_IN			256
 #define MAX_IATU_OUT			256
 
+/* Synopsys Vendor specific data */
+#define DW_PCIE_RAS_CAP_ID		0x2
+
 struct pcie_port;
 struct dw_pcie;
 struct dw_pcie_ep;
@@ -284,6 +287,7 @@ struct dw_pcie {
 
 u8 dw_pcie_find_capability(struct dw_pcie *pci, u8 cap);
 u16 dw_pcie_find_ext_capability(struct dw_pcie *pci, u8 cap);
+u16 dw_pcie_find_vsec_capability(struct dw_pcie *pci, u8 vsec_cap);
 
 int dw_pcie_read(void __iomem *addr, int size, u32 *val);
 int dw_pcie_write(void __iomem *addr, int size, u32 val);
-- 
2.17.1