1x86 PCI DT details:
2===================
3
4Some options are available to affect how PCI operates on x86.
5
6Optional properties:
7- u-boot,skip-auto-config-until-reloc : Don't set up PCI configuration until
8	after U-Boot has relocated. Normally if PCI is used before relocation,
9	this happens before relocation also. Some platforms set up static
10	configuration in TPL/SPL to reduce code size and boot time, since these
11	phases only know about a small subset of PCI devices.
12
13For PCI devices the following optional property is available:
14
15- pci,no-autoconfig : Don't automatically configure this PCI device at all.
16	This is used when the device is statically configured and must maintain
17	this same config throughout the boot process. An example is a serial
18	UART being used to debug PCI configuration, since reconfiguring it stops
19	the UART from working until the driver is re-probed, and this can cause
20	output to be lost. This should not generally be used in production code,
21	although it is often harmless.
22
23- u-boot,pci-pre-reloc : List of vendor/device IDs to bind before relocation, even
24	if they are not bridges. This is useful if the device is needed (e.g. a
25	UART). The format is 0xvvvvdddd where d is the device ID and v is the
26	vendor ID.
27
28Example:
29
30pci {
31	compatible = "pci-x86";
32	#address-cells = <3>;
33	#size-cells = <2>;
34	bootph-all;
35	ranges = <0x02000000 0x0 0xc0000000 0xc0000000 0 0x10000000
36		0x42000000 0x0 0xb0000000 0xb0000000 0 0x10000000
37		0x01000000 0x0 0x1000 0x1000 0 0xefff>;
38	u-boot,skip-auto-config-until-reloc;
39	u-boot,pci-pre-reloc = <
40		PCI_VENDEV(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_APL_UART2)>;
41
42	serial: serial@18,2 {
43		reg = <0x0200c210 0 0 0 0>;
44		bootph-all;
45		compatible = "intel,apl-ns16550";
46		early-regs = <0xde000000 0x20>;
47		reg-shift = <2>;
48		clock-frequency = <1843200>;
49		current-speed = <115200>;
50		pci,no-autoconfig;
51	};
52};
53