On Wed, Mar 19, 2025 at 02:09:03PM +0800, Peter Chen wrote:

Hello Peter,

On 25-03-07 16:01:24, Siddharth Vadapalli wrote:

quoted

EXTERNAL EMAIL

Hello,

This series enables support to build the PCIe Cadence Controller drivers
and the PCI J721E Application/Wrapper/Glue driver as Loadable Kernel
Modules. The motivation for this series is that PCIe is not a necessity
for booting the SoC, due to which it doesn't have to be a built-in
module. Additionally, the defconfig doesn't enable the PCIe Cadence
Controller drivers and the PCI J721E driver, due to which PCIe is not
supported by default. Enabling the configs as of now (i.e. without this
series) will result in built-in drivers i.e. a bloated Linux Image for
everyone who doesn't have the PCIe Controller.

If the user doesn't enable PCIe controller device through DTS/ACPI,
that's doesn't matter.

The Linux Image for arm64 systems built using:
arch/arm64/configs/defconfig
will not have support for the Cadence PCIe Controller and the PCIe J721e
driver, because these configs aren't enabled.

quoted

@@ -209,6 +209,12 @@ CONFIG_NFC=m
 CONFIG_NFC_NCI=m
 CONFIG_NFC_S3FWRN5_I2C=m
 CONFIG_PCI=y
+CONFIG_PCI_J721E=m
+CONFIG_PCI_J721E_HOST=m
+CONFIG_PCI_J721E_EP=m
+CONFIG_PCIE_CADENCE=m
+CONFIG_PCIE_CADENCE_HOST=m
+CONFIG_PCIE_CADENCE_EP=m

The common Cadence configuration will be select if the glue layer's
configuration is select according to Kconfig.

Please do not set common configuration as module, some user may need
it as build-in like dw's. Considering the situation, the rootfs is at
NVMe.

The common configuration at the moment is "DISABLED" i.e. no support for
the Cadence Controller at all. Which "user" are you referring to? This
series was introduced since having the drivers built-in was pushed back at:
https://lore.kernel.org/linux-arm-kernel/20250122145822.4ewsmkk6ztbeejzf@slashing/ (local)

Regards,
Siddharth.