Hi Simon,
On Wed, Apr 7, 2021 at 12:32 PM Simon Glass sjg@chromium.org wrote:
At present only bridge devices are bound before relocation, to save space in pre-relocation memory. In some cases we do actually want to bind a device, e.g. because it provides the console UART. Add a devicetree binding to support this.
Use the PCI_VENDEV() macro to encode the cell value. This is present in U-Boot but not used, so move it to the binding header-file.
Signed-off-by: Simon Glass sjg@chromium.org
doc/device-tree-bindings/pci/x86-pci.txt | 7 ++++- drivers/pci/pci-uclass.c | 33 +++++++++++++++++++++++- include/dt-bindings/pci/pci.h | 12 +++++++++ include/pci.h | 1 - 4 files changed, 50 insertions(+), 3 deletions(-) create mode 100644 include/dt-bindings/pci/pci.h
diff --git a/doc/device-tree-bindings/pci/x86-pci.txt b/doc/device-tree-bindings/pci/x86-pci.txt index 95e370b3e72..cf4e5ed595a 100644 --- a/doc/device-tree-bindings/pci/x86-pci.txt +++ b/doc/device-tree-bindings/pci/x86-pci.txt @@ -20,6 +20,10 @@ For PCI devices the following optional property is available: output to be lost. This should not generally be used in production code, although it is often harmless.
+- u-boot,pci-pre-reloc : List of vendor/device IDs to bind before relocation, even
if they are not bridges. This is useful if the device is needed (e.g. aUART). The format is 0xvvvvdddd where d is the device ID and v is thevendor ID.
Can we reuse "u-boot,dm-pre-reloc" to do such thing?
The following is an example from arch/x86/dts/crownbay.dts
pciuart0: uart@a,1 { compatible = "pci8086,8811.00", "pci8086,8811", "pciclass,070002", "pciclass,0700", "ns16550"; u-boot,dm-pre-reloc; reg = <0x00025100 0x0 0x0 0x0 0x0 0x01025110 0x0 0x0 0x0 0x0>; reg-shift = <0>; clock-frequency = <1843200>; current-speed = <115200>; };
Regards, Bin