On 2018-01-05 18:18, Lorenzo Pieralisi wrote:
Hi Lorenzo,
This is exactly what I'm trying to explain:
The host starts of with a (hardcoded today) subord of 1. [bits 16:23]
Since commit a20c7f36bd3d, downstream devices cannot assign bus nr's
higher than the subord of the upstream device.
So in this case, scanning stops after the bridge as soon as bus 1 is
assigned .. :)
There is one thing that I need to understand though. Before the commit
above, how would enumeration works given that the subordinate bus number
was set to 1 and that the kernel, AFAICS, does not overwrite it ?
Are you able to send me a log (enumeration with debugging enabled and
lspci) with the commit above reverted please ?
Thanks,
Lorenzo
Info below as requested:
[ 0.116729] OF: PCI: host bridge /soc/pcie@0x01000000 ranges:
[ 0.116748] OF: PCI: No bus range found for /soc/pcie@0x01000000,
using [bus 00-ff]
[ 0.116777] OF: PCI: IO 0x01f80000..0x01f8ffff -> 0x00000000
[ 0.116796] OF: PCI: MEM 0x01000000..0x01efffff -> 0x01000000
[ 0.337917] imx6q-pcie 1ffc000.pcie: link up
[ 0.337934] imx6q-pcie 1ffc000.pcie: Link: Gen2 disabled
[ 0.337947] imx6q-pcie 1ffc000.pcie: link up
[ 0.337958] imx6q-pcie 1ffc000.pcie: Link up, Gen1
[ 0.338197] imx6q-pcie 1ffc000.pcie: PCI host bridge to bus 0000:00
[ 0.338215] pci_bus 0000:00: root bus resource [bus 00-ff]
[ 0.338230] pci_bus 0000:00: root bus resource [io 0x0000-0xffff]
[ 0.338243] pci_bus 0000:00: root bus resource [mem
0x01000000-0x01efffff]
[ 0.338255] pci_bus 0000:00: scanning bus
[ 0.338286] pci 0000:00:00.0: [16c3:abcd] type 01 class 0x060400
[ 0.338311] pci 0000:00:00.0: reg 0x10: [mem 0x00000000-0x000fffff]
[ 0.338328] pci 0000:00:00.0: reg 0x38: [mem 0x00000000-0x0000ffff pref]
[ 0.338362] pci 0000:00:00.0: calling pci_fixup_ide_bases+0x0/0x4c
[ 0.338416] pci 0000:00:00.0: supports D1
[ 0.338425] pci 0000:00:00.0: PME# supported from D0 D1 D3hot D3cold
[ 0.338436] pci 0000:00:00.0: PME# disabled
[ 0.338664] pci_bus 0000:00: fixups for bus
[ 0.338676] PCI: bus0: Fast back to back transfers disabled
[ 0.338692] pci 0000:00:00.0: scanning [bus 01-01] behind bridge, pass 0
[ 0.338822] pci_bus 0000:01: scanning bus
[ 0.338926] pci 0000:01:00.0: [10b5:8604] type 01 class 0x060400
[ 0.338969] pci 0000:01:00.0: calling ventana_pciesw_early_fixup+0x0/0xa4
[ 0.457984] pci 0000:01:00.0: reg 0x10: [mem 0x00000000-0x0001ffff]
[ 0.458167] pci 0000:01:00.0: calling pci_fixup_ide_bases+0x0/0x4c
[ 0.458635] pci 0000:01:00.0: PME# supported from D0 D3hot D3cold
[ 0.458660] pci 0000:01:00.0: PME# disabled
[ 0.458970] pci_bus 0000:01: fixups for bus
[ 0.459027] PCI: bus1: Fast back to back transfers disabled
[ 0.459052] pci 0000:01:00.0: scanning [bus 00-00] behind bridge, pass 0
[ 0.459060] pci 0000:01:00.0: bridge configuration invalid ([bus
00-00]), reconfiguring
[ 0.459115] pci 0000:01:00.0: scanning [bus 00-00] behind bridge, pass 1
[ 0.459443] pci_bus 0000:02: busn_res: can not insert [bus 02-ff]
under [bus 01] (conflicts with (null) [bus 01])
[ 0.459461] pci_bus 0000:02: scanning bus
[ 0.459573] pci 0000:02:01.0: [10b5:8604] type 01 class 0x060400
[ 0.459617] pci 0000:02:01.0: calling ventana_pciesw_early_fixup+0x0/0xa4
[ 0.459865] pci 0000:02:01.0: calling pci_fixup_ide_bases+0x0/0x4c
[ 0.460298] pci 0000:02:01.0: PME# supported from D0 D3hot D3cold
[ 0.460321] pci 0000:02:01.0: PME# disabled
[ 0.460719] pci 0000:02:04.0: [10b5:8604] type 01 class 0x060400
[ 0.460760] pci 0000:02:04.0: calling ventana_pciesw_early_fixup+0x0/0xa4
[ 0.461009] pci 0000:02:04.0: calling pci_fixup_ide_bases+0x0/0x4c
[ 0.461436] pci 0000:02:04.0: PME# supported from D0 D3hot D3cold
[ 0.461460] pci 0000:02:04.0: PME# disabled
[ 0.461841] pci 0000:02:05.0: [10b5:8604] type 01 class 0x060400
[ 0.461883] pci 0000:02:05.0: calling ventana_pciesw_early_fixup+0x0/0xa4
[ 0.462128] pci 0000:02:05.0: calling pci_fixup_ide_bases+0x0/0x4c
[ 0.462553] pci 0000:02:05.0: PME# supported from D0 D3hot D3cold
[ 0.462578] pci 0000:02:05.0: PME# disabled
[ 0.463084] pci_bus 0000:02: fixups for bus
[ 0.463231] PCI: bus2: Fast back to back transfers disabled
[ 0.463255] pci 0000:02:01.0: scanning [bus 00-00] behind bridge, pass 0
[ 0.463264] pci 0000:02:01.0: bridge configuration invalid ([bus
00-00]), reconfiguring
[ 0.463319] pci 0000:02:04.0: scanning [bus 00-00] behind bridge, pass 0
[ 0.463328] pci 0000:02:04.0: bridge configuration invalid ([bus
00-00]), reconfiguring
[ 0.463378] pci 0000:02:05.0: scanning [bus 00-00] behind bridge, pass 0
[ 0.463385] pci 0000:02:05.0: bridge configuration invalid ([bus
00-00]), reconfiguring
[ 0.463435] pci 0000:02:01.0: scanning [bus 00-00] behind bridge, pass 1
[ 0.463764] pci_bus 0000:03: scanning bus
[ 0.463785] pci_bus 0000:03: fixups for bus
[ 0.463791] PCI: bus3: Fast back to back transfers enabled
[ 0.463803] pci_bus 0000:03: bus scan returning with max=03
[ 0.463814] pci_bus 0000:03: busn_res: [bus 03-ff] end is updated to 03
[ 0.463833] pci_bus 0000:03: [bus 03] partially hidden behind bridge
0000:01 [bus 01]
[ 0.463862] pci 0000:02:04.0: scanning [bus 00-00] behind bridge, pass 1
[ 0.464178] pci_bus 0000:04: scanning bus
[ 0.464197] pci_bus 0000:04: fixups for bus
[ 0.464202] PCI: bus4: Fast back to back transfers enabled
[ 0.464214] pci_bus 0000:04: bus scan returning with max=04
[ 0.464223] pci_bus 0000:04: busn_res: [bus 04-ff] end is updated to 04
[ 0.464242] pci_bus 0000:04: [bus 04] partially hidden behind bridge
0000:01 [bus 01]
[ 0.464271] pci 0000:02:05.0: scanning [bus 00-00] behind bridge, pass 1
[ 0.464586] pci_bus 0000:05: scanning bus
[ 0.464691] pci 0000:05:00.0: [168c:0033] type 00 class 0x028000
[ 0.464825] pci 0000:05:00.0: reg 0x10: [mem 0x00000000-0x0001ffff 64bit]
[ 0.465036] pci 0000:05:00.0: reg 0x30: [mem 0x00000000-0x0000ffff pref]
[ 0.465095] pci 0000:05:00.0: calling pci_fixup_ide_bases+0x0/0x4c
[ 0.465117] pci 0000:05:00.0: calling quirk_no_bus_reset+0x0/0x20
[ 0.465489] pci 0000:05:00.0: supports D1
[ 0.465498] pci 0000:05:00.0: PME# supported from D0 D1 D3hot
[ 0.465524] pci 0000:05:00.0: PME# disabled
[ 0.465859] pci_bus 0000:05: fixups for bus
[ 0.465903] PCI: bus5: Fast back to back transfers disabled
[ 0.465916] pci_bus 0000:05: bus scan returning with max=05
[ 0.465926] pci_bus 0000:05: busn_res: [bus 05-ff] end is updated to 05
[ 0.465946] pci_bus 0000:05: [bus 05] partially hidden behind bridge
0000:01 [bus 01]
[ 0.465965] pci_bus 0000:02: bus scan returning with max=05
[ 0.465974] pci_bus 0000:02: busn_res: [bus 02-ff] end is updated to 05
[ 0.465984] pci_bus 0000:02: busn_res: can not insert [bus 02-05]
under [bus 01] (conflicts with (null) [bus 01])
[ 0.466005] pci_bus 0000:02: [bus 02-05] partially hidden behind
bridge 0000:01 [bus 01]
[ 0.466026] pci_bus 0000:01: bus scan returning with max=05
[ 0.466033] pci 0000:00:00.0: bridge has subordinate 01 but max busn 05
[ 0.466049] pci 0000:00:00.0: scanning [bus 01-01] behind bridge, pass 1
[ 0.466059] pci_bus 0000:00: bus scan returning with max=01
[ 0.466186] pci 0000:00:00.0: fixup irq: got 298
[ 0.466196] pci 0000:00:00.0: assigning IRQ 298
[ 0.466247] pci 0000:01:00.0: fixup irq: got 298
[ 0.466254] pci 0000:01:00.0: assigning IRQ 298
[ 0.466374] pci 0000:02:01.0: fixup irq: got 299
[ 0.466382] pci 0000:02:01.0: assigning IRQ 299
[ 0.466436] pci 0000:02:04.0: fixup irq: got 298
[ 0.466442] pci 0000:02:04.0: assigning IRQ 298
[ 0.466501] pci 0000:02:05.0: fixup irq: got 299
[ 0.466509] pci 0000:02:05.0: assigning IRQ 299
[ 0.466562] pci 0000:05:00.0: fixup irq: got 299
[ 0.466569] pci 0000:05:00.0: assigning IRQ 299
[ 0.466807] pci 0000:00:00.0: BAR 0: assigned [mem 0x01000000-0x010fffff]
[ 0.466825] pci 0000:00:00.0: BAR 8: assigned [mem 0x01100000-0x012fffff]
[ 0.466843] pci 0000:00:00.0: BAR 6: assigned [mem
0x01300000-0x0130ffff pref]
[ 0.466862] pci 0000:01:00.0: BAR 8: assigned [mem 0x01100000-0x011fffff]
[ 0.466875] pci 0000:01:00.0: BAR 0: assigned [mem 0x01200000-0x0121ffff]
[ 0.466908] pci 0000:02:05.0: BAR 8: assigned [mem 0x01100000-0x011fffff]
[ 0.466919] pci 0000:02:01.0: PCI bridge to [bus 03]
[ 0.467001] pci 0000:02:04.0: PCI bridge to [bus 04]
[ 0.467086] pci 0000:05:00.0: BAR 0: assigned [mem
0x01100000-0x0111ffff 64bit]
[ 0.467160] pci 0000:05:00.0: BAR 6: assigned [mem
0x01120000-0x0112ffff pref]
[ 0.467171] pci 0000:02:05.0: PCI bridge to [bus 05]
[ 0.467206] pci 0000:02:05.0: bridge window [mem 0x01100000-0x011fffff]
[ 0.467262] pci 0000:01:00.0: PCI bridge to [bus 02-05]
[ 0.467297] pci 0000:01:00.0: bridge window [mem 0x01100000-0x011fffff]
[ 0.467352] pci 0000:00:00.0: PCI bridge to [bus 01]
[ 0.467364] pci 0000:00:00.0: bridge window [mem 0x01100000-0x012fffff]
[ 0.467627] pcieport 0000:00:00.0: Signaling PME through PCIe PME
interrupt
[ 0.467643] pci 0000:01:00.0: Signaling PME through PCIe PME interrupt
[ 0.467653] pci 0000:02:01.0: Signaling PME through PCIe PME interrupt
[ 0.467662] pci 0000:02:04.0: Signaling PME through PCIe PME interrupt
[ 0.467671] pci 0000:02:05.0: Signaling PME through PCIe PME interrupt
[ 0.467680] pci 0000:05:00.0: Signaling PME through PCIe PME interrupt
[ 0.467694] pcie_pme 0000:00:00.0:pcie001: service driver pcie_pme loaded
[ 0.468019] pcieport 0000:01:00.0: enabling device (0140 -> 0142)
[ 0.468147] pcieport 0000:01:00.0: enabling bus mastering
[ 0.468886] pcieport 0000:02:01.0: enabling bus mastering
[ 0.469576] pcieport 0000:02:04.0: enabling bus mastering
[ 0.470165] pcieport 0000:02:05.0: enabling device (0140 -> 0142)
[ 0.470275] pcieport 0000:02:05.0: enabling bus mastering
[ Node 4 | node-4 ] lspci -v
00:00.0 PCI bridge: Synopsys, Inc. Device abcd (rev 01) (prog-if 00
[Normal decode])
Flags: bus master, fast devsel, latency 0, IRQ 298
Memory at 01000000 (32-bit, non-prefetchable) [size=1M]
Bus: primary=00, secondary=01, subordinate=01, sec-latency=0
I/O behind bridge: None
Memory behind bridge: 01100000-012fffff [size=2M]
Prefetchable memory behind bridge: None
[virtual] Expansion ROM at 01300000 [disabled] [size=64K]
Capabilities: [40] Power Management version 3
Capabilities: [50] MSI: Enable- Count=1/1 Maskable+ 64bit+
Capabilities: [70] Express Root Port (Slot-), MSI 00
Capabilities: [100] Advanced Error Reporting
Capabilities: [140] Virtual Channel
Kernel driver in use: pcieport
lspci: Unable to load libkmod resources: error -12
01:00.0 PCI bridge: PLX Technology, Inc. PEX 8604 4-lane, 4-Port PCI
Express Gen 2 (5.0 GT/s) Switch (rev ba) (prog-if 00 [Normal decode])
Flags: bus master, fast devsel, latency 0, IRQ 298
Memory at 01200000 (32-bit, non-prefetchable) [size=128K]
Bus: primary=01, secondary=02, subordinate=05, sec-latency=0
I/O behind bridge: None
Memory behind bridge: 01100000-011fffff [size=1M]
Prefetchable memory behind bridge: None
Capabilities: [40] Power Management version 3
Capabilities: [48] MSI: Enable- Count=1/4 Maskable+ 64bit+
Capabilities: [68] Express Upstream Port, MSI 00
Capabilities: [a4] Subsystem: PLX Technology, Inc. PEX 8604 4-lane,
4-Port PCI Express Gen 2 (5.0 GT/s) Switch
Capabilities: [100] Device Serial Number ba-86-01-10-b5-df-0e-00
Capabilities: [fb4] Advanced Error Reporting
Capabilities: [138] Power Budgeting <?>
Capabilities: [148] Virtual Channel
Capabilities: [448] Vendor Specific Information: ID=0000 Rev=0
Len=0cc <?>
Capabilities: [950] Vendor Specific Information: ID=0001 Rev=0
Len=010 <?>
Kernel driver in use: pcieport
02:01.0 PCI bridge: PLX Technology, Inc. PEX 8604 4-lane, 4-Port PCI
Express Gen 2 (5.0 GT/s) Switch (rev ba) (prog-if 00 [Normal decode])
Flags: bus master, fast devsel, latency 0, IRQ 299
Bus: primary=02, secondary=03, subordinate=03, sec-latency=0
I/O behind bridge: None
Memory behind bridge: None
Prefetchable memory behind bridge: None
Capabilities: [40] Power Management version 3
Capabilities: [48] MSI: Enable- Count=1/4 Maskable+ 64bit+
Capabilities: [68] Express Downstream Port (Slot+), MSI 00
Capabilities: [a4] Subsystem: PLX Technology, Inc. PEX 8604 4-lane,
4-Port PCI Express Gen 2 (5.0 GT/s) Switch
Capabilities: [100] Device Serial Number ba-86-01-10-b5-df-0e-00
Capabilities: [fb4] Advanced Error Reporting
Capabilities: [148] Virtual Channel
Capabilities: [520] Access Control Services
Capabilities: [950] Vendor Specific Information: ID=0001 Rev=0
Len=010 <?>
Kernel driver in use: pcieport
02:04.0 PCI bridge: PLX Technology, Inc. PEX 8604 4-lane, 4-Port PCI
Express Gen 2 (5.0 GT/s) Switch (rev ba) (prog-if 00 [Normal decode])
Flags: bus master, fast devsel, latency 0, IRQ 298
Bus: primary=02, secondary=04, subordinate=04, sec-latency=0
I/O behind bridge: None
Memory behind bridge: None
Prefetchable memory behind bridge: None
Capabilities: [40] Power Management version 3
Capabilities: [48] MSI: Enable- Count=1/4 Maskable+ 64bit+
Capabilities: [68] Express Downstream Port (Slot+), MSI 00
Capabilities: [a4] Subsystem: PLX Technology, Inc. PEX 8604 4-lane,
4-Port PCI Express Gen 2 (5.0 GT/s) Switch
Capabilities: [100] Device Serial Number ba-86-01-10-b5-df-0e-00
Capabilities: [fb4] Advanced Error Reporting
Capabilities: [148] Virtual Channel
Capabilities: [520] Access Control Services
Capabilities: [950] Vendor Specific Information: ID=0001 Rev=0
Len=010 <?>
Kernel driver in use: pcieport
02:05.0 PCI bridge: PLX Technology, Inc. PEX 8604 4-lane, 4-Port PCI
Express Gen 2 (5.0 GT/s) Switch (rev ba) (prog-if 00 [Normal decode])
Flags: bus master, fast devsel, latency 0, IRQ 299
Bus: primary=02, secondary=05, subordinate=05, sec-latency=0
I/O behind bridge: None
Memory behind bridge: 01100000-011fffff [size=1M]
Prefetchable memory behind bridge: None
Capabilities: [40] Power Management version 3
Capabilities: [48] MSI: Enable- Count=1/4 Maskable+ 64bit+
Capabilities: [68] Express Downstream Port (Slot+), MSI 00
Capabilities: [a4] Subsystem: PLX Technology, Inc. PEX 8604 4-lane,
4-Port PCI Express Gen 2 (5.0 GT/s) Switch
Capabilities: [100] Device Serial Number ba-86-01-10-b5-df-0e-00
Capabilities: [fb4] Advanced Error Reporting
Capabilities: [148] Virtual Channel
Capabilities: [520] Access Control Services
Capabilities: [950] Vendor Specific Information: ID=0001 Rev=0
Len=010 <?>
Kernel driver in use: pcieport
05:00.0 Network controller: Qualcomm Atheros AR958x 802.11abgn Wireless
Network Adapter (rev 01)
Subsystem: Device 19b6:d016
Flags: bus master, fast devsel, latency 0, IRQ 299
Memory at 01100000 (64-bit, non-prefetchable) [size=128K]
[virtual] Expansion ROM at 01120000 [disabled] [size=64K]
Capabilities: [40] Power Management version 3
Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
Capabilities: [70] Express Endpoint, MSI 00
Capabilities: [100] Advanced Error Reporting
Capabilities: [140] Virtual Channel
Capabilities: [300] Device Serial Number 00-00-00-00-00-00-00-00
Kernel driver in use: ath9k
