On Fri, 2025-11-14 at 08:03 +0100, Arnd Bergmann wrote:

On Fri, Nov 14, 2025, at 06:47, Siddharth Vadapalli wrote:

quoted

On Thu, 2025-11-13 at 11:13 +0100, Arnd Bergmann wrote:

quoted

On Thu, Nov 13, 2025, at 10:27, Siddharth Vadapalli wrote:

quoted

Thank you for the suggestion. I think that the following Makefile changes
will be sufficient and Kconfig doesn't need to be modified:

diff --git a/drivers/pci/controller/cadence/Makefile

b/drivers/pci/controller/cadence/Makefile
index 5e23f8539ecc..1a97c9b249b8 100644

--- a/drivers/pci/controller/cadence/Makefile
+++ b/drivers/pci/controller/cadence/Makefile

@@ -4,4 +4,6 @@ obj-$(CONFIG_PCIE_CADENCE_HOST) += pcie-cadence-host.o
 obj-$(CONFIG_PCIE_CADENCE_EP) += pcie-cadence-ep.o
 obj-$(CONFIG_PCIE_CADENCE_PLAT) += pcie-cadence-plat.o
 obj-$(CONFIG_PCI_J721E) += pci-j721e.o
+pci_j721e-y := pci-j721e.o pcie-cadence.o
 obj-$(CONFIG_PCIE_SG2042_HOST) += pcie-sg2042.o
+pci_sg2042_host-y := pci-sg2042.o pcie-cadence.o

If either of PCI_J721E or SG2042_HOST is selected as a built-in module,
then pcie-cadence-host.c, pcie-cadence-ep.c and pcie-cadence.c drivers will
be built-in. If both PCI_J721E and SG2042_HOST are selected as loadable
modules, only then the library drivers will be enabled as loadable modules.

Please let me know what you think.

I don't think that the version above does what you want,
this would build the pcie-cadence.o file into three separate
modules and break in additional ways if a subset of them are
built-in.

I would still suggest combining pcie-cadence{,-ep,-host}.o into
one module that is used by the other drivers, as that would address
the build failure you are observing.

An alternative would be to change the pcie-j721e.c file to only
reference the host portion if host support is enabled for this
driver.

While 'pcie-cadence.h' handles the case where 'PCIE_CADENCE_HOST' is not
defined:

#if IS_ENABLED(CONFIG_PCIE_CADENCE_HOST)
...
void cdns_pcie_host_disable(struct cdns_pcie_rc *rc);
...
#else
...
static inline void cdns_pcie_host_disable(struct cdns_pcie_rc *rc)
{
}
...
#endif

the issue occurs because PCIE_SG2042_HOST enables CONFIG_PCIE_CADENCE_HOST
but it is enabled as 'm'. As a result, the definition exists in pcie-
cadence-host.c that is built as a loadable module which is not accessible
by pci-j721e.c that is built-in.

I understand that the solution should be fixing the pci-j721e.c driver
rather than updating Kconfig or Makefile. Thank you for the feedback. I
will update the pci-j721e.c driver to handle the case that is triggering
the build error.

Regards,
Siddharth.