Hi, I'm running linux-2.6.33 on a custom board based on 460EX CPU (powerpc). There's a PCI-PCI bridge on this board, PLX 6254, and a single hot-pluggable device behind the bridge. When this device is plugged in before system boots everything works fine: bridge and device are properly recognized by kernel, resources are allocated and device memory regions are accessible. Below is relevant kernel messages and lspci output: PCI: Probing PCI hardware pci_bus 0000:00: scanning bus pci 0000:00:02.0: found [3388:0020] class 000604 header type 01 pci 0000:00:02.0: calling pcibios_fixup_resources+0x0/0xf4 pci 0000:00:02.0: calling fixup_ppc4xx_pci_bridge+0x0/0x154 pci 0000:00:02.0: calling quirk_resource_alignment+0x0/0x200 pci 0000:00:02.0: supports D1 D2 pci 0000:00:02.0: PME# supported from D0 D1 D2 D3hot pci 0000:00:02.0: PME# disabled pci_bus 0000:00: fixups for bus pci 0000:00:02.0: scanning behind bridge, config 010100, pass 0 pci_bus 0000:01: scanning bus pci 0000:01:00.0: found [1575:0002] class 00ff00 header type 00 pci 0000:01:00.0: reg 10: [mem 0x80000000-0x800fffff] pci 0000:01:00.0: reg 14: [mem 0x84000000-0x87ffffff] pci 0000:01:00.0: reg 18: [mem 0x88000000-0x8bffffff] pci 0000:01:00.0: reg 1c: [mem 0x8c000000-0x8c003fff] pci 0000:01:00.0: calling pcibios_fixup_resources+0x0/0xf4 pci 0000:01:00.0: calling fixup_ppc4xx_pci_bridge+0x0/0x154 pci 0000:01:00.0: calling quirk_resource_alignment+0x0/0x200 pci_bus 0000:01: fixups for bus pci 0000:00:02.0: PCI bridge to [bus 01-01] pci 0000:00:02.0: bridge window [mem 0x80000000-0x8c0fffff] pci_bus 0000:01: bus scan returning with max=01 pci 0000:00:02.0: scanning behind bridge, config 010100, pass 1 pci_bus 0000:00: bus scan returning with max=01 pci 0000:00:02.0: BAR 8: assigned [mem 0xd80000000-0xd89ffffff] pci 0000:01:00.0: BAR 1: assigned [mem 0xd80000000-0xd83ffffff] pci 0000:01:00.0: BAR 1: set to [mem 0xd80000000-0xd83ffffff] (PCI address [0x80000000-0x83ffffff] pci 0000:01:00.0: BAR 2: assigned [mem 0xd84000000-0xd87ffffff] pci 0000:01:00.0: BAR 2: set to [mem 0xd84000000-0xd87ffffff] (PCI address [0x84000000-0x87ffffff] pci 0000:01:00.0: BAR 0: assigned [mem 0xd88000000-0xd880fffff] pci 0000:01:00.0: BAR 0: set to [mem 0xd88000000-0xd880fffff] (PCI address [0x88000000-0x880fffff] pci 0000:01:00.0: BAR 3: assigned [mem 0xd88100000-0xd88103fff] pci 0000:01:00.0: BAR 3: set to [mem 0xd88100000-0xd88103fff] (PCI address [0x88100000-0x88103fff] pci 0000:00:02.0: PCI bridge to [bus 01-01] pci 0000:00:02.0: bridge window [io disabled] pci 0000:00:02.0: bridge window [mem 0xd80000000-0xd89ffffff] pci 0000:00:02.0: bridge window [mem pref disabled] pci_bus 0000:00: resource 0 [io 0x0000-0xffff] pci_bus 0000:00: resource 1 [mem 0xd80000000-0xdffffffff] pci_bus 0000:01: resource 1 [mem 0xd80000000-0xd89ffffff] 00:02.0 PCI bridge: Hint Corp HB6 Universal PCI-PCI bridge (transparent mode) (rev 04) 00: 88 33 20 00 87 00 b0 02 04 00 04 06 08 80 01 00 10: 00 00 00 00 00 00 00 00 00 01 01 00 f1 01 a0 02 20: 00 80 f0 89 f1 ff 01 00 00 00 00 00 00 00 00 00 30: 00 00 00 00 dc 00 00 00 00 00 00 00 00 00 00 00 The problem arises when device is plugged in after boot. After doing echo 1 > /sys/bus/pci/rescan the device is identified, but bridge memory window is not allocated, and reads from device memory regions return 0xffffffff. Below is relevant output: PCI: Probing PCI hardware pci_bus 0000:00: scanning bus pci 0000:00:02.0: found [3388:0020] class 000604 header type 01 pci 0000:00:02.0: calling pcibios_fixup_resources+0x0/0xf4 pci 0000:00:02.0: calling fixup_ppc4xx_pci_bridge+0x0/0x154 pci 0000:00:02.0: calling quirk_resource_alignment+0x0/0x200 pci 0000:00:02.0: supports D1 D2 pci 0000:00:02.0: PME# supported from D0 D1 D2 D3hot pci 0000:00:02.0: PME# disabled pci_bus 0000:00: fixups for bus pci 0000:00:02.0: scanning behind bridge, config 010100, pass 0 pci_bus 0000:01: scanning bus pci_bus 0000:01: fixups for bus pci 0000:00:02.0: PCI bridge to [bus 01-01] pci_bus 0000:01: bus scan returning with max=01 pci 0000:00:02.0: scanning behind bridge, config 010100, pass 1 pci_bus 0000:00: bus scan returning with max=01 pci 0000:00:02.0: PCI bridge to [bus 01-01] pci 0000:00:02.0: bridge window [io disabled] pci 0000:00:02.0: bridge window [mem disabled] pci 0000:00:02.0: bridge window [mem pref disabled] pci_bus 0000:00: resource 0 [io 0x0000-0xffff] pci_bus 0000:00: resource 1 [mem 0xd80000000-0xdffffffff] pci 0000:00:02.0: calling quirk_cardbus_legacy+0x0/0x54 pci 0000:00:02.0: calling quirk_usb_early_handoff+0x0/0x6cc PCI: CLS 32 bytes, default 32 pci_bus 0000:00: scanning bus pci 0000:00:02.0: scanning behind bridge, config 010100, pass 0 pci_bus 0000:01: scanning bus pci 0000:01:00.0: found [1575:0002] class 00ff00 header type 00 pci 0000:01:00.0: reg 10: [mem 0x00000000-0x000fffff] pci 0000:01:00.0: reg 14: [mem 0x00000000-0x03ffffff] pci 0000:01:00.0: reg 18: [mem 0x00000000-0x03ffffff] pci 0000:01:00.0: reg 1c: [mem 0x00000000-0x00003fff] pci 0000:01:00.0: calling pcibios_fixup_resources+0x0/0xf4 pci 0000:01:00.0: calling fixup_ppc4xx_pci_bridge+0x0/0x154 pci 0000:01:00.0: calling quirk_resource_alignment+0x0/0x200 pci_bus 0000:01: bus scan returning with max=01 pci 0000:00:02.0: scanning behind bridge, config 010100, pass 1 pci_bus 0000:00: bus scan returning with max=01 pci 0000:00:02.0: BAR 8: assigned [mem 0xd80000000-0xd89ffffff] pci 0000:01:00.0: BAR 1: assigned [mem 0xd80000000-0xd83ffffff] pci 0000:01:00.0: BAR 1: set to [mem 0xd80000000-0xd83ffffff] (PCI address [0x80000000-0x83ffffff] pci 0000:01:00.0: BAR 2: assigned [mem 0xd84000000-0xd87ffffff] pci 0000:01:00.0: BAR 2: set to [mem 0xd84000000-0xd87ffffff] (PCI address [0x84000000-0x87ffffff] pci 0000:01:00.0: BAR 0: assigned [mem 0xd88000000-0xd880fffff] pci 0000:01:00.0: BAR 0: set to [mem 0xd88000000-0xd880fffff] (PCI address [0x88000000-0x880fffff] pci 0000:01:00.0: BAR 3: assigned [mem 0xd88100000-0xd88103fff] pci 0000:01:00.0: BAR 3: set to [mem 0xd88100000-0xd88103fff] (PCI address [0x88100000-0x88103fff] 00:02.0 PCI bridge: Hint Corp HB6 Universal PCI-PCI bridge (transparent mode) (rev 04) 00: 88 33 20 00 87 00 b0 02 04 00 04 06 08 80 01 00 10: 00 00 00 00 00 00 00 00 00 01 01 00 f1 01 a0 02 20: f0 ff 00 00 f1 ff 01 00 00 00 00 00 00 00 00 00 30: 00 00 00 00 dc 00 00 00 00 00 00 00 00 00 00 00 As you can see, the PLX BAR at address 0x20 is not properly configured. Writing the value 0x89f08000 using setpci fixes access to hot-plugged device. Any idea why PCI bus rescan fails to allocate bridge memory window ? Thanks a lot. Felix. -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
