问题描述如下：
linux 启动后，运行命令“lspci -v”，我们可以看到 pci 设备可以找到，但没有分配地址给设备。通过进一步检查 linux 启动消息，可以发现许多类似“bridge window mem ...”的消息。不确定这些消息是正常的还是实际上是地址分配失败的迹象。
我正在运行的处理器是飞思卡尔 p2010，它是 powerpc 架构。bootloader是我们自己设计的，没有接触pci相关的东西。所以我们完全依赖Linux内核自己做完整的pci枚举。
在 Linux 内核 pci 枚举开始之前，我们唯一做的就是为 pci 空间使用配置一个 LAW 窗口（特别是 LAW4）。此外，当然，根据我们的硬件配置对 dts 文件进行适当的修改。我们认为完成所有这些准备后，Linux 内核应该能够使所有 pci 东西正常工作，但事实并非如此。
那么，有没有人知道如何解决这个问题或曾经遇到过类似的问题并且可以对此有所了解？非常感谢！
更多信息附在下面：
========内核启动参数===============
root=/dev/ram rw ip=off console=ttyS0,9600
========dts中的PCI部分设置=======
pci0: pcie@fbf0a000 {
interrupt-map-mask = <0xf800 0x0 0x0 0x7>;
interrupt-map = <
00000 0x0 0x0 0x1 &mpic 0x0 0x1
00000 0x0 0x0 0x2 &mpic 0x1 0x1
00000 0x0 0x0 0x3 &mpic 0x2 0x1
00000 0x0 0x0 0x4 &mpic 0x3 0x1>;
interrupt-parent = <&mpic>;
interrupts = <26 2>;
bus-range = <0 255>;
ranges = <0x2000000 0x0 0x80000000 0x80000000 0x0 0x40000000
0x1000000 0x0 0x0 0xd3000000 0x0 0x100000>;
clock-frequency = <33333333>;
#interrupt-cells = <1>;
#size-cells = <2>;
#address-cells = <3>;
reg = <0xfbf0a000 0x1000>;
compatible = "fsl,mpc8548-pcie";
device_type = "pci";
fsl,pcie-access-big-endian;
pcie@0 {
reg = <0x0 0x0 0x0 0x0 0x0>;
#size-cells = <2>;
#address-cells = <3>;
device_type = "pci";
ranges = <0x2000000 0x0 0x80000000
0x2000000 0x0 0x80000000
0x0 0x40000000
0x1000000 0x0 0x0
0x1000000 0x0 0x0
0x0 0x100000>;
};
};
==============“lspci -v”的结果===============
# lspci -v
0000:00:00.0 Class 0b20: 1957:007b (rev 21)
!!! Invalid class 0b20 for header type 01
Flags: bus master, fast devsel, latency 0
Memory at <ignored> (32-bit, non-prefetchable)
Bus: primary=00, secondary=01, subordinate=07, sec-latency=0
I/O behind bridge: 00000000-00000fff
Memory behind bridge: 00000000-000fffff
Prefetchable memory behind bridge: 0000000000000000-0000000000000000
Capabilities: [44] Power Management version 2
Capabilities: [4c] #10 [0041]
0000:01:00.0 Class 0604: 10b5:8606 (rev ba)
Flags: bus master, fast devsel, latency 0
Bus: primary=01, secondary=02, subordinate=07, sec-latency=0
Capabilities: [40] Power Management version 3
Capabilities: [48] Message Signalled Interrupts: 64bit+ Queue=0/2 Enable+
Capabilities: [68] #10 [0052]
Capabilities: [a4] #0d [0000]
0000:02:01.0 Class 0604: 10b5:8606 (rev ba)
Flags: bus master, fast devsel, latency 0
Bus: primary=02, secondary=03, subordinate=03, sec-latency=0
Capabilities: [40] Power Management version 3
Capabilities: [48] Message Signalled Interrupts: 64bit+ Queue=0/2 Enable+
Capabilities: [68] #10 [0162]
Capabilities: [a4] #0d [0000]
0000:02:04.0 Class 0604: 10b5:8606 (rev ba)
Flags: bus master, fast devsel, latency 0
Bus: primary=02, secondary=04, subordinate=04, sec-latency=0
Capabilities: [40] Power Management version 3
Capabilities: [48] Message Signalled Interrupts: 64bit+ Queue=0/2 Enable+
Capabilities: [68] #10 [0162]
Capabilities: [a4] #0d [0000]
0000:02:05.0 Class 0604: 10b5:8606 (rev ba)
Flags: bus master, fast devsel, latency 0
Bus: primary=02, secondary=05, subordinate=05, sec-latency=0
Capabilities: [40] Power Management version 3
Capabilities: [48] Message Signalled Interrupts: 64bit+ Queue=0/2 Enable+
Capabilities: [68] #10 [0162]
Capabilities: [a4] #0d [0000]
0000:02:07.0 Class 0604: 10b5:8606 (rev ba)
Flags: bus master, fast devsel, latency 0
Bus: primary=02, secondary=06, subordinate=06, sec-latency=0
Capabilities: [40] Power Management version 3
Capabilities: [48] Message Signalled Interrupts: 64bit+ Queue=0/2 Enable+
Capabilities: [68] #10 [0162]
Capabilities: [a4] #0d [0000]
0000:02:09.0 Class 0604: 10b5:8606 (rev ba)
Flags: bus master, fast devsel, latency 0
Bus: primary=02, secondary=07, subordinate=07, sec-latency=0
Capabilities: [40] Power Management version 3
Capabilities: [48] Message Signalled Interrupts: 64bit+ Queue=0/2 Enable+
Capabilities: [68] #10 [0162]
Capabilities: [a4] #0d [0000]
0000:03:00.0 Class 0580: 10ee:7011
Subsystem: 10ee:0007
Flags: fast devsel, IRQ 17
Capabilities: [40] Power Management version 3
Capabilities: [48] Message Signalled Interrupts: 64bit+ Queue=0/0 Enable-
Capabilities: [60] #10 [0002]
0000:04:00.0 Class 0580: 10ee:7011
Subsystem: 10ee:0007
Flags: fast devsel, IRQ 16
Capabilities: [40] Power Management version 3
Capabilities: [48] Message Signalled Interrupts: 64bit+ Queue=0/0 Enable-
Capabilities: [60] #10 [0002]
0000:05:00.0 Class 0200: 14e4:8372 (rev 13)
Subsystem: 14e4:8372
Flags: fast devsel, IRQ 17
Memory at <ignored> (64-bit, non-prefetchable)
Capabilities: [48] Power Management version 3
Capabilities: [50] Vital Product Data
Capabilities: [58] Message Signalled Interrupts: 64bit+ Queue=0/3 Enable-
Capabilities: [ac] #10 [0002]
0000:06:00.0 Class 0200: 14e4:8372 (rev 13)
Subsystem: 14e4:8372
Flags: fast devsel, IRQ 18
Memory at <ignored> (64-bit, non-prefetchable)
Capabilities: [48] Power Management version 3
Capabilities: [50] Vital Product Data
Capabilities: [58] Message Signalled Interrupts: 64bit+ Queue=0/3 Enable-
Capabilities: [ac] #10 [0002]
#
=======================Linux内核启动消息====================
irq: irq 47 on host /soc@fbf00000/pic@40000 mapped to virtual irq 47
PCI: Probing PCI hardware
pci 0000:00:00.0: ignoring class b20 (doesn't match header type 01)
pci 0000:00:00.0: supports D1 D2
pci 0000:00:00.0: PME# supported from D0 D1 D2 D3hot D3cold
pci 0000:00:00.0: PME# disabled
pci 0000:01:00.0: reg 10: [mem 0x00000000-0x0001ffff]
pci 0000:01:00.0: PME# supported from D0 D3hot D3cold
pci 0000:01:00.0: PME# disabled
pci 0000:00:00.0: PCI bridge to [bus 01-ff]
pci 0000:00:00.0: bridge window [io 0x0000-0x0000] (disabled)
pci 0000:00:00.0: bridge window [mem 0x00000000-0x000fffff] (disabled)
pci 0000:00:00.0: bridge window [mem 0x00000000-0x000fffff pref] (disabled)
irq: irq 0 on host /soc@fbf00000/pic@40000 mapped to virtual irq 16
pci 0000:02:01.0: PME# supported from D0 D3hot D3cold
pci 0000:02:01.0: PME# disabled
pci 0000:02:04.0: PME# supported from D0 D3hot D3cold
pci 0000:02:04.0: PME# disabled
pci 0000:02:05.0: PME# supported from D0 D3hot D3cold
pci 0000:02:05.0: PME# disabled
pci 0000:02:07.0: PME# supported from D0 D3hot D3cold
pci 0000:02:07.0: PME# disabled
pci 0000:02:09.0: PME# supported from D0 D3hot D3cold
pci 0000:02:09.0: PME# disabled
pci 0000:01:00.0: PCI bridge to [bus 02-ff]
pci 0000:01:00.0: bridge window [io 0xf000-0x0000] (disabled)
pci 0000:01:00.0: bridge window [mem 0xfff00000-0x000fffff] (disabled)
pci 0000:01:00.0: bridge window [mem 0xfff00000-0x000fffff pref] (disabled)
irq: irq 1 on host /soc@fbf00000/pic@40000 mapped to virtual irq 17
irq: irq 3 on host /soc@fbf00000/pic@40000 mapped to virtual irq 18
pci 0000:03:00.0: reg 10: [mem 0x00000000-0x00003fff]
pci 0000:03:00.0: PME# supported from D0 D1 D2 D3hot
pci 0000:03:00.0: PME# disabled
pci 0000:02:01.0: PCI bridge to [bus 03-ff]
pci 0000:02:01.0: bridge window [io 0xf000-0x0000] (disabled)
pci 0000:02:01.0: bridge window [mem 0xfff00000-0x000fffff] (disabled)
pci 0000:02:01.0: bridge window [mem 0xfff00000-0x000fffff pref] (disabled)
pci 0000:04:00.0: reg 10: [mem 0x00000000-0x00003fff]
pci 0000:04:00.0: PME# supported from D0 D1 D2 D3hot
pci 0000:04:00.0: PME# disabled
pci 0000:02:04.0: PCI bridge to [bus 04-ff]
pci 0000:02:04.0: bridge window [io 0xf000-0x0000] (disabled)
pci 0000:02:04.0: bridge window [mem 0xfff00000-0x000fffff] (disabled)
pci 0000:02:04.0: bridge window [mem 0xfff00000-0x000fffff pref] (disabled)
pci 0000:05:00.0: reg 10: [mem 0x80400000-0x8043ffff 64bit]
pci 0000:05:00.0: PME# supported from D0 D3hot D3cold
pci 0000:05:00.0: PME# disabled
pci 0000:02:05.0: PCI bridge to [bus 05-ff]
pci 0000:02:05.0: bridge window [io 0xf000-0x0000] (disabled)
pci 0000:02:05.0: bridge window [mem 0xfff00000-0x000fffff] (disabled)
pci 0000:02:05.0: bridge window [mem 0xfff00000-0x000fffff pref] (disabled)
pci 0000:06:00.0: reg 10: [mem 0x80500000-0x8053ffff 64bit]
pci 0000:06:00.0: PME# supported from D0 D3hot D3cold
pci 0000:06:00.0: PME# disabled
pci 0000:02:07.0: PCI bridge to [bus 06-ff]
pci 0000:02:07.0: bridge window [io 0xf000-0x0000] (disabled)
pci 0000:02:07.0: bridge window [mem 0xfff00000-0x000fffff] (disabled)
pci 0000:02:07.0: bridge window [mem 0xfff00000-0x000fffff pref] (disabled)
pci 0000:02:09.0: PCI bridge to [bus 07-ff]
pci 0000:02:09.0: bridge window [io 0xf000-0x0000] (disabled)
pci 0000:02:09.0: bridge window [mem 0xfff00000-0x000fffff] (disabled)
pci 0000:02:09.0: bridge window [mem 0xfff00000-0x000fffff pref] (disabled)
PCI: Cannot allocate resource region 0 of device 0000:05:00.0, will remap
PCI: Cannot allocate resource region 0 of device 0000:06:00.0, will remap
pci 0000:01:00.0: BAR 8: can't assign mem (size 0x400000)
pci 0000:01:00.0: BAR 0: can't assign mem (size 0x20000)
pci 0000:02:01.0: BAR 8: can't assign mem (size 0x100000)
pci 0000:02:04.0: BAR 8: can't assign mem (size 0x100000)
pci 0000:02:05.0: BAR 8: can't assign mem (size 0x100000)
pci 0000:02:07.0: BAR 8: can't assign mem (size 0x100000)
pci 0000:03:00.0: BAR 0: can't assign mem (size 0x4000)
pci 0000:02:01.0: PCI bridge to [bus 03-03]
pci 0000:02:01.0: bridge window [io disabled]
pci 0000:02:01.0: bridge window [mem disabled]
pci 0000:02:01.0: bridge window [mem pref disabled]
pci 0000:04:00.0: BAR 0: can't assign mem (size 0x4000)
pci 0000:02:04.0: PCI bridge to [bus 04-04]
pci 0000:02:04.0: bridge window [io disabled]
pci 0000:02:04.0: bridge window [mem disabled]
pci 0000:02:04.0: bridge window [mem pref disabled]
pci 0000:05:00.0: BAR 0: can't assign mem (size 0x40000)
pci 0000:02:05.0: PCI bridge to [bus 05-05]
pci 0000:02:05.0: bridge window [io disabled]
pci 0000:02:05.0: bridge window [mem disabled]
pci 0000:02:05.0: bridge window [mem pref disabled]
pci 0000:06:00.0: BAR 0: can't assign mem (size 0x40000)
pci 0000:02:07.0: PCI bridge to [bus 06-06]
pci 0000:02:07.0: bridge window [io disabled]
pci 0000:02:07.0: bridge window [mem disabled]
pci 0000:02:07.0: bridge window [mem pref disabled]
pci 0000:02:09.0: PCI bridge to [bus 07-07]
pci 0000:02:09.0: bridge window [io disabled]
pci 0000:02:09.0: bridge window [mem disabled]
pci 0000:02:09.0: bridge window [mem pref disabled]
pci 0000:01:00.0: PCI bridge to [bus 02-07]
pci 0000:01:00.0: bridge window [io disabled]
pci 0000:01:00.0: bridge window [mem disabled]
pci 0000:01:00.0: bridge window [mem pref disabled]
pci 0000:00:00.0: not setting up bridge for bus 0000:01
pci_bus 0000:00: resource 0 [io 0xffafd000-0xffbfcfff]
pci_bus 0000:00: resource 1 [mem 0x80000000-0xbfffffff]
Registering qe_ic with sysfs...
bio: create slab <bio-0> at 0
vgaarb: loaded
Generic PHY: Registered new driver