[PATCH v4 1/2] PCI: dwc: Add support for vendor specific capability search

Shradha Todi
2024-12-06T08:34:26Z

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

Signed-off-by: Shradha Todi <shradha.t@samsung.com>
---
drivers/pci/controller/dwc/pcie-designware.c | 16 ++++++++++++++++
drivers/pci/controller/dwc/pcie-designware.h | 1 +
2 files changed, 17 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 6d6cbc8b5b2c..41230c5e4a53 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -277,6 +277,22 @@ 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 347ab74ac35a..98a057820bc7 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -476,6 +476,7 @@ void dw_pcie_version_detect(struct dw_pcie *pci);

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