[PATCH v6 3/3] PCI: imx6: Add support for i.MX6 PCIe controller

[Tim Harvey]

On Fri, Oct 18, 2013 at 12:45 AM, Zhu Richard-R65037
<r65037 at freescale.com> wrote:

[...]

>
> >
> > Richard,
> >
> > I would suspect this is the imprecise abort issue.  Please see my patch
> > (http://thread.gmane.org/gmane.linux.kernel.pci/26159) resolves that for you
> > and reply to that thread if so.
> >
> > I believe that the imprecise abort's only occurs if you have a PCIe switch on
> > the bus - is this your topology and if so are you experiencing any issues with
> > devices behind the bus that use io regions?  If you do have a switch, perhaps
> > you can provide me with an 'lspci -v' for comparison.
> >
> Hi Tim:
> Oh, It's great. Your patch can fix my problem.
> My own patch-set of pcie driver works well when my Pericom's switch is used.
> Thanks a lot.

Good to hear!  Please reply to that thread and provide an Acked-by and
Tested-by so we can get that patch upstream.

>
> Yes, it is.
> E1000e network card request about 32 bytes IO regions during the bus enumeration procedure,
> and it works well behind the my Pericom's switch.
>
> Based on my own pcie driver(not the one up-streamed by Sean),

How about with the upstream driver?  I have 'my own driver' as well
(based on Freescale's BSP) which works, but I'm very interested in
getting this upstream driver to work so we don't have to keep
maintaining our own drivers.  Can you please test with this upstream
driver?

> Here are the log and the lspci -v results I got just now:
>
> imx-pcie 1ffc000.pcie: legacy_irq 155
> imx-pcie 1ffc000.pcie: map [mem 0x01ffc000-0x01ffffff]
> imx-pcie 1ffc000.pcie: starting to link pcie port.
> imx-pcie 1ffc000.pcie: Link up
> PCI host bridge to bus 0000:00
> pci_bus 0000:00: root bus resource [io  0x1000-0x10000]
> pci_bus 0000:00: root bus resource [mem 0x01000000-0x01efffff]
> pci_bus 0000:00: No busn resource found for root bus, will use [bus 00-ff]
> PCI: bus0: Fast back to back transfers disabled
> PCI: bus1: Fast back to back transfers disabled
> pci 0000:01:00.0: bridge configuration invalid ([bus 00-00]), reconfiguring
> PCI: bus2: Fast back to back transfers disabled
> pci 0000:02:01.0: bridge configuration invalid ([bus 00-00]), reconfiguring
> pci 0000:02:02.0: bridge configuration invalid ([bus 00-00]), reconfiguring
> PCI: bus3: Fast back to back transfers disabled
> PCI: bus4: Fast back to back transfers enabled
> pci 0000:00:00.0: BAR 0: assigned [mem 0x01000000-0x010fffff]
> pci 0000:00:00.0: BAR 8: assigned [mem 0x01100000-0x011fffff]
> pci 0000:00:00.0: BAR 9: assigned [mem 0x01200000-0x012fffff pref]
> pci 0000:00:00.0: BAR 6: assigned [mem 0x01300000-0x0130ffff pref]
> pci 0000:00:00.0: BAR 7: assigned [io  0x1000-0x1fff]
> pci 0000:01:00.0: BAR 8: assigned [mem 0x01100000-0x011fffff]
> pci 0000:01:00.0: BAR 9: assigned [mem 0x01200000-0x012fffff pref]
> pci 0000:01:00.0: BAR 7: assigned [io  0x1000-0x1fff]
> pci 0000:02:01.0: BAR 8: assigned [mem 0x01100000-0x011fffff]
> pci 0000:02:01.0: BAR 9: assigned [mem 0x01200000-0x012fffff pref]
> pci 0000:02:01.0: BAR 7: assigned [io  0x1000-0x1fff]
> pci 0000:03:00.0: BAR 1: assigned [mem 0x01100000-0x0117ffff]
> pci 0000:03:00.0: BAR 6: assigned [mem 0x01200000-0x0123ffff pref]
> pci 0000:03:00.0: BAR 0: assigned [mem 0x01180000-0x0119ffff]
> pci 0000:03:00.0: BAR 3: assigned [mem 0x011a0000-0x011a3fff]
> pci 0000:03:00.0: BAR 2: assigned [io  0x1000-0x101f]
> pci 0000:02:01.0: PCI bridge to [bus 03]
> pci 0000:02:01.0:   bridge window [io  0x1000-0x1fff]
> pci 0000:02:01.0:   bridge window [mem 0x01100000-0x011fffff]
> pci 0000:02:01.0:   bridge window [mem 0x01200000-0x012fffff pref]
> pci 0000:02:02.0: PCI bridge to [bus 04]
> pci 0000:01:00.0: PCI bridge to [bus 02-04]
> pci 0000:01:00.0:   bridge window [io  0x1000-0x1fff]
> pci 0000:01:00.0:   bridge window [mem 0x01100000-0x011fffff]
> pci 0000:01:00.0:   bridge window [mem 0x01200000-0x012fffff pref]
> pci 0000:00:00.0: PCI bridge to [bus 01-04]
> pci 0000:00:00.0:   bridge window [io  0x1000-0x1fff]
> pci 0000:00:00.0:   bridge window [mem 0x01100000-0x011fffff]
> pci 0000:00:00.0:   bridge window [mem 0x01200000-0x012fffff pref]
> PCI: enabling device 0000:01:00.0 (0140 -> 0143)
> PCI: enabling device 0000:02:01.0 (0140 -> 0143)
> PCI: enabling device 0000:02:02.0 (0140 -> 0143)
> ...
> root at freescale ~$ lspci -v
> 00:00.0 PCI bridge: Unknown device 16c3:abcd (rev 01) (prog-if 00 [Normal decode])
>         Flags: bus master, fast devsel, latency 0
>         Memory at 01000000 (32-bit, non-prefetchable) [size=1M]
>         Bus: primary=00, secondary=01, subordinate=04, sec-latency=0
>         I/O behind bridge: 00001000-00001fff
>         Memory behind bridge: 01100000-011fffff
>         Prefetchable memory behind bridge: 01200000-012fffff
>         [virtual] Expansion ROM at 01300000 [disabled] [size=64K]
>         Capabilities: [40] Power Management version 3
>         Capabilities: [50] Message Signalled Interrupts: Mask+ 64bit+ Queue=0/0 Enable-
>         Capabilities: [70] Express Root Port (Slot-) IRQ 0
>         Capabilities: [100] Advanced Error Reporting
>         Capabilities: [140] Virtual Channel
>
> 01:00.0 PCI bridge: Pericom Semiconductor Unknown device 2303 (rev 05) (prog-if 00 [Normal decode])
>         Flags: bus master, fast devsel, latency 0
>         Bus: primary=01, secondary=02, subordinate=04, sec-latency=0
>         I/O behind bridge: 00001000-00001fff
>         Memory behind bridge: 01100000-011fffff
>         Prefetchable memory behind bridge: 0000000001200000-00000000012fffff
>         Capabilities: [40] Power Management version 3
>         Capabilities: [5c] Vital Product Data
>         Capabilities: [64] Vendor Specific Information
>         Capabilities: [b0] Subsystem: Gammagraphx, Inc. Unknown device 0000
>         Capabilities: [c0] Express Upstream Port IRQ 0
>         Capabilities: [100] Advanced Error Reporting
>         Capabilities: [140] Virtual Channel
>         Capabilities: [20c] Power Budgeting
>         Capabilities: [230] Unknown (24)
>
> 02:01.0 PCI bridge: Pericom Semiconductor Unknown device 2303 (rev 05) (prog-if 00 [Normal decode])
>         Flags: bus master, fast devsel, latency 0
>         Bus: primary=02, secondary=03, subordinate=03, sec-latency=0
>         I/O behind bridge: 00001000-00001fff
>         Memory behind bridge: 01100000-011fffff
>         Prefetchable memory behind bridge: 0000000001200000-00000000012fffff
>         Capabilities: [40] Power Management version 3
>         Capabilities: [4c] Message Signalled Interrupts: Mask- 64bit+ Queue=0/0 Enable-
>         Capabilities: [64] Vendor Specific Information
>         Capabilities: [b0] Subsystem: Gammagraphx, Inc. Unknown device 0000
>         Capabilities: [c0] Express Downstream Port (Slot+) IRQ 0
>         Capabilities: [100] Advanced Error Reporting
>         Capabilities: [140] Virtual Channel
>         Capabilities: [20c] Power Budgeting
>         Capabilities: [220] Unknown (13)
>
> 02:02.0 PCI bridge: Pericom Semiconductor Unknown device 2303 (rev 05) (prog-if 00 [Normal decode])
>         Flags: bus master, fast devsel, latency 0
>         Bus: primary=02, secondary=04, subordinate=04, sec-latency=0
>         Capabilities: [40] Power Management version 3
>         Capabilities: [4c] Message Signalled Interrupts: Mask- 64bit+ Queue=0/0 Enable-
>         Capabilities: [64] Vendor Specific Information
>         Capabilities: [b0] Subsystem: Gammagraphx, Inc. Unknown device 0000
>         Capabilities: [c0] Express Downstream Port (Slot+) IRQ 0
>         Capabilities: [100] Advanced Error Reporting
>         Capabilities: [140] Virtual Channel
>         Capabilities: [20c] Power Budgeting
>         Capabilities: [220] Unknown (13)
>
> 03:00.0 Ethernet controller: Intel Corporation Unknown device 10d3
>         Subsystem: Intel Corporation Unknown device a01f
>         Flags: bus master, fast devsel, latency 0, IRQ 154
>         Memory at 01180000 (32-bit, non-prefetchable) [size=128K]
>         Memory at 01100000 (32-bit, non-prefetchable) [size=512K]
>         I/O ports at 1000 [disabled] [size=32]
>         Memory at 011a0000 (32-bit, non-prefetchable) [size=16K]
>         [virtual] Expansion ROM at 01200000 [disabled] [size=256K]
>         Capabilities: [c8] Power Management version 2
>         Capabilities: [d0] Message Signalled Interrupts: Mask- 64bit+ Queue=0/0 Enable-
>         Capabilities: [e0] Express Endpoint IRQ 0
>         Capabilities: [a0] MSI-X: Enable- Mask- TabSize=5
>         Capabilities: [100] Advanced Error Reporting
>         Capabilities: [140] Device Serial Number 8b-18-3a-ff-ff-21-1b-00
>

The above device does show an io resource but it says its disabled?
I'm not sure what that means, but I'm not convinced you would see the
same issue as I do if the io resource isn't being used.

Tim