Re: [PATCH V13 2/5] PCI: Create device tree node for bridge

Guenter Roeck
2023-08-31T13:57:58Z

On Tue, Aug 15, 2023 at 10:19:57AM -0700, Lizhi Hou wrote:
> The PCI endpoint device such as Xilinx Alveo PCI card maps the register
> spaces from multiple hardware peripherals to its PCI BAR. Normally,
> the PCI core discovers devices and BARs using the PCI enumeration process.
> There is no infrastructure to discover the hardware peripherals that are
> present in a PCI device, and which can be accessed through the PCI BARs.
>
> Apparently, the device tree framework requires a device tree node for the
> PCI device. Thus, it can generate the device tree nodes for hardware
> peripherals underneath. Because PCI is self discoverable bus, there might
> not be a device tree node created for PCI devices. Furthermore, if the PCI
> device is hot pluggable, when it is plugged in, the device tree nodes for
> its parent bridges are required. Add support to generate device tree node
> for PCI bridges.
>
> Add an of_pci_make_dev_node() interface that can be used to create device
> tree node for PCI devices.
>
> Add a PCI_DYNAMIC_OF_NODES config option. When the option is turned on,
> the kernel will generate device tree nodes for PCI bridges unconditionally.
>
> Initially, add the basic properties for the dynamically generated device
> tree nodes which include #address-cells, #size-cells, device_type,
> compatible, ranges, reg.
>
> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
> Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>

This patch results in the following build error.

Building sparc64:allmodconfig ... failed
--------------
Error log:
<stdin>:1519:2: warning: #warning syscall clone3 not implemented [-Wcpp]
sparc64-linux-ld: drivers/pci/of_property.o: in function `of_pci_prop_intr_map':
of_property.c:(.text+0xc4): undefined reference to `of_irq_parse_raw'

Guenter