.../pci/controller/dwc/pcie-designware-ep.c | 31 ++----------------- drivers/pci/controller/dwc/pcie-designware.h | 21 +++++++++++++ 2 files changed, 23 insertions(+), 29 deletions(-)
The PCI core now provides generic PCI_FIND_NEXT_CAP() macros to search
for PCI capabilities, using config accessors we supply.
Use them in the DWC EP driver to implement dw_pcie_ep_find_capability()
instead of duplicating the algorithm.
Signed-off-by: Hans Zhang <18255117159@163.com>
---
Changes for v2:
https://patchwork.kernel.org/project/linux-pci/patch/20250616152515.966480-1-18255117159@163.com/
- Rebase to v6.17-rc1.
- Based on the following branch:
https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git/log/?h=capability-search
---
.../pci/controller/dwc/pcie-designware-ep.c | 31 ++-----------------
drivers/pci/controller/dwc/pcie-designware.h | 21 +++++++++++++
2 files changed, 23 insertions(+), 29 deletions(-)
diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 0ae54a94809b..7f2112c2fb21 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -69,37 +69,10 @@ void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar)
}
EXPORT_SYMBOL_GPL(dw_pcie_ep_reset_bar);
-static u8 __dw_pcie_ep_find_next_cap(struct dw_pcie_ep *ep, u8 func_no,
- u8 cap_ptr, u8 cap)
-{
- u8 cap_id, next_cap_ptr;
- u16 reg;
-
- if (!cap_ptr)
- return 0;
-
- reg = dw_pcie_ep_readw_dbi(ep, func_no, cap_ptr);
- cap_id = (reg & 0x00ff);
-
- if (cap_id > PCI_CAP_ID_MAX)
- return 0;
-
- if (cap_id == cap)
- return cap_ptr;
-
- next_cap_ptr = (reg & 0xff00) >> 8;
- return __dw_pcie_ep_find_next_cap(ep, func_no, next_cap_ptr, cap);
-}
-
static u8 dw_pcie_ep_find_capability(struct dw_pcie_ep *ep, u8 func_no, u8 cap)
{
- u8 next_cap_ptr;
- u16 reg;
-
- reg = dw_pcie_ep_readw_dbi(ep, func_no, PCI_CAPABILITY_LIST);
- next_cap_ptr = (reg & 0x00ff);
-
- return __dw_pcie_ep_find_next_cap(ep, func_no, next_cap_ptr, cap);
+ return PCI_FIND_NEXT_CAP(dw_pcie_ep_read_cfg, PCI_CAPABILITY_LIST,
+ cap, ep, func_no);
}
/**
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index b5e7e18138a6..a44f2113925d 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -695,6 +695,27 @@ static inline u8 dw_pcie_ep_readb_dbi(struct dw_pcie_ep *ep, u8 func_no,
return dw_pcie_ep_read_dbi(ep, func_no, reg, 0x1);
}
+static inline int dw_pcie_ep_read_cfg_byte(struct dw_pcie_ep *ep, u8 func_no,
+ int where, u8 *val)
+{
+ *val = dw_pcie_ep_readb_dbi(ep, func_no, where);
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static inline int dw_pcie_ep_read_cfg_word(struct dw_pcie_ep *ep, u8 func_no,
+ int where, u16 *val)
+{
+ *val = dw_pcie_ep_readw_dbi(ep, func_no, where);
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static inline int dw_pcie_ep_read_cfg_dword(struct dw_pcie_ep *ep, u8 func_no,
+ int where, u32 *val)
+{
+ *val = dw_pcie_ep_readl_dbi(ep, func_no, where);
+ return PCIBIOS_SUCCESSFUL;
+}
+
static inline unsigned int dw_pcie_ep_get_dbi2_offset(struct dw_pcie_ep *ep,
u8 func_no)
{
base-commit: 8742b2d8935f476449ef37e263bc4da3295c7b58
--
2.25.1Hi Hans,
kernel test robot noticed the following build errors:
[auto build test ERROR on 8742b2d8935f476449ef37e263bc4da3295c7b58]
url: https://github.com/intel-lab-lkp/linux/commits/Hans-Zhang/PCI-endpoint-Implement-capability-search-using-PCI-core-APIs/20250819-231353
base: 8742b2d8935f476449ef37e263bc4da3295c7b58
patch link: https://lore.kernel.org/r/20250819145828.438541-1-18255117159%40163.com
patch subject: [PATCH v2] PCI: endpoint: Implement capability search using PCI core APIs
config: x86_64-randconfig-002-20250826 (https://download.01.org/0day-ci/archive/20250826/202508261929.5s2blqmA-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14+deb12u1) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250826/202508261929.5s2blqmA-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202508261929.5s2blqmA-lkp@intel.com/
All error/warnings (new ones prefixed by >>):
drivers/pci/controller/dwc/pcie-designware-ep.c: In function 'dw_pcie_ep_find_capability':
>> drivers/pci/controller/dwc/pcie-designware-ep.c:74:16: error: implicit declaration of function 'PCI_FIND_NEXT_CAP' [-Werror=implicit-function-declaration]
74 | return PCI_FIND_NEXT_CAP(dw_pcie_ep_read_cfg, PCI_CAPABILITY_LIST,
| ^~~~~~~~~~~~~~~~~
>> drivers/pci/controller/dwc/pcie-designware-ep.c:74:34: error: 'dw_pcie_ep_read_cfg' undeclared (first use in this function); did you mean 'dw_pcie_ep_read_dbi'?
74 | return PCI_FIND_NEXT_CAP(dw_pcie_ep_read_cfg, PCI_CAPABILITY_LIST,
| ^~~~~~~~~~~~~~~~~~~
| dw_pcie_ep_read_dbi
drivers/pci/controller/dwc/pcie-designware-ep.c:74:34: note: each undeclared identifier is reported only once for each function it appears in
>> drivers/pci/controller/dwc/pcie-designware-ep.c:76:1: warning: control reaches end of non-void function [-Wreturn-type]
76 | }
| ^
cc1: some warnings being treated as errors
vim +/PCI_FIND_NEXT_CAP +74 drivers/pci/controller/dwc/pcie-designware-ep.c
71
72 static u8 dw_pcie_ep_find_capability(struct dw_pcie_ep *ep, u8 func_no, u8 cap)
73 {
> 74 return PCI_FIND_NEXT_CAP(dw_pcie_ep_read_cfg, PCI_CAPABILITY_LIST,
75 cap, ep, func_no);
> 76 }
77
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi，
Please ignore it because there is no problem compiling in this branch.
And it depends on this series.
https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git/log/?h=capability-search
Best regards,
Hans
On 2025/8/26 19:58, kernel test robot wrote:
> Hi Hans,
>
> kernel test robot noticed the following build errors:
>
> [auto build test ERROR on 8742b2d8935f476449ef37e263bc4da3295c7b58]
>
> url: https://github.com/intel-lab-lkp/linux/commits/Hans-Zhang/PCI-endpoint-Implement-capability-search-using-PCI-core-APIs/20250819-231353
> base: 8742b2d8935f476449ef37e263bc4da3295c7b58
> patch link: https://lore.kernel.org/r/20250819145828.438541-1-18255117159%40163.com
> patch subject: [PATCH v2] PCI: endpoint: Implement capability search using PCI core APIs
> config: x86_64-randconfig-002-20250826 (https://download.01.org/0day-ci/archive/20250826/202508261929.5s2blqmA-lkp@intel.com/config)
> compiler: gcc-12 (Debian 12.2.0-14+deb12u1) 12.2.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250826/202508261929.5s2blqmA-lkp@intel.com/reproduce)
>
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202508261929.5s2blqmA-lkp@intel.com/
>
> All error/warnings (new ones prefixed by >>):
>
> drivers/pci/controller/dwc/pcie-designware-ep.c: In function 'dw_pcie_ep_find_capability':
>>> drivers/pci/controller/dwc/pcie-designware-ep.c:74:16: error: implicit declaration of function 'PCI_FIND_NEXT_CAP' [-Werror=implicit-function-declaration]
> 74 | return PCI_FIND_NEXT_CAP(dw_pcie_ep_read_cfg, PCI_CAPABILITY_LIST,
> | ^~~~~~~~~~~~~~~~~
>>> drivers/pci/controller/dwc/pcie-designware-ep.c:74:34: error: 'dw_pcie_ep_read_cfg' undeclared (first use in this function); did you mean 'dw_pcie_ep_read_dbi'?
> 74 | return PCI_FIND_NEXT_CAP(dw_pcie_ep_read_cfg, PCI_CAPABILITY_LIST,
> | ^~~~~~~~~~~~~~~~~~~
> | dw_pcie_ep_read_dbi
> drivers/pci/controller/dwc/pcie-designware-ep.c:74:34: note: each undeclared identifier is reported only once for each function it appears in
>>> drivers/pci/controller/dwc/pcie-designware-ep.c:76:1: warning: control reaches end of non-void function [-Wreturn-type]
> 76 | }
> | ^
> cc1: some warnings being treated as errors
>
>
> vim +/PCI_FIND_NEXT_CAP +74 drivers/pci/controller/dwc/pcie-designware-ep.c
>
> 71
> 72 static u8 dw_pcie_ep_find_capability(struct dw_pcie_ep *ep, u8 func_no, u8 cap)
> 73 {
> > 74 return PCI_FIND_NEXT_CAP(dw_pcie_ep_read_cfg, PCI_CAPABILITY_LIST,
> 75 cap, ep, func_no);
> > 76 }
> 77
>
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