PCI: cadence: Implement capability search using PCI core APIs

The PCI core now provides generic PCI_FIND_NEXT_CAP() and
PCI_FIND_NEXT_EXT_CAP() macros to search for PCI capabilities, using
config accessors we supply.

Use them in the CDNS driver to add cdns_pcie_find_capability() and
cdns_pcie_find_ext_capability() interfaces.

Signed-off-by: Hans Zhang <18255117159@163.com>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20250813144529.303548-6-18255117159@163.com

diff --git a/drivers/pci/controller/cadence/pcie-cadence.c b/drivers/pci/controller/cadence/pcie-cadence.c
index 70a19573440ee9fc0ea78310505a25830cc45247..c45585ae17468609d29d8a8fa07f5ca571873f40 100644 (file)
--- a/drivers/pci/controller/cadence/pcie-cadence.c
+++ b/drivers/pci/controller/cadence/pcie-cadence.c
@@ -8,6 +8,20 @@
 #include <linux/of.h>
 
 #include "pcie-cadence.h"
+#include "../../pci.h"
+
+u8 cdns_pcie_find_capability(struct cdns_pcie *pcie, u8 cap)
+{
+       return PCI_FIND_NEXT_CAP(cdns_pcie_read_cfg, PCI_CAPABILITY_LIST,
+                                cap, pcie);
+}
+EXPORT_SYMBOL_GPL(cdns_pcie_find_capability);
+
+u16 cdns_pcie_find_ext_capability(struct cdns_pcie *pcie, u8 cap)
+{
+       return PCI_FIND_NEXT_EXT_CAP(cdns_pcie_read_cfg, 0, cap, pcie);
+}
+EXPORT_SYMBOL_GPL(cdns_pcie_find_ext_capability);
 
 void cdns_pcie_detect_quiet_min_delay_set(struct cdns_pcie *pcie)
 {

diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
index 1d81c4bf6c6db7844816f01490e53f3a3d6b8c27..9eebf8f02abc1ea04a86768440dccd8c2d3bf8a1 100644 (file)
--- a/drivers/pci/controller/cadence/pcie-cadence.h
+++ b/drivers/pci/controller/cadence/pcie-cadence.h
@@ -367,6 +367,37 @@ static inline u32 cdns_pcie_readl(struct cdns_pcie *pcie, u32 reg)
        return readl(pcie->reg_base + reg);
 }
 
+static inline u16 cdns_pcie_readw(struct cdns_pcie *pcie, u32 reg)
+{
+       return readw(pcie->reg_base + reg);
+}
+
+static inline u8 cdns_pcie_readb(struct cdns_pcie *pcie, u32 reg)
+{
+       return readb(pcie->reg_base + reg);
+}
+
+static inline int cdns_pcie_read_cfg_byte(struct cdns_pcie *pcie, int where,
+                                         u8 *val)
+{
+       *val = cdns_pcie_readb(pcie, where);
+       return PCIBIOS_SUCCESSFUL;
+}
+
+static inline int cdns_pcie_read_cfg_word(struct cdns_pcie *pcie, int where,
+                                         u16 *val)
+{
+       *val = cdns_pcie_readw(pcie, where);
+       return PCIBIOS_SUCCESSFUL;
+}
+
+static inline int cdns_pcie_read_cfg_dword(struct cdns_pcie *pcie, int where,
+                                          u32 *val)
+{
+       *val = cdns_pcie_readl(pcie, where);
+       return PCIBIOS_SUCCESSFUL;
+}
+
 static inline u32 cdns_pcie_read_sz(void __iomem *addr, int size)
 {
        void __iomem *aligned_addr = PTR_ALIGN_DOWN(addr, 0x4);
@@ -536,6 +567,9 @@ static inline void cdns_pcie_ep_disable(struct cdns_pcie_ep *ep)
 }
 #endif
 
+u8 cdns_pcie_find_capability(struct cdns_pcie *pcie, u8 cap);
+u16 cdns_pcie_find_ext_capability(struct cdns_pcie *pcie, u8 cap);
+
 void cdns_pcie_detect_quiet_min_delay_set(struct cdns_pcie *pcie);
 
 void cdns_pcie_set_outbound_region(struct cdns_pcie *pcie, u8 busnr, u8 fn,