questions: second of the 2 pcie controllers does not scan the bus.

questions: second of the 2 pcie controllers does not scan the bus.

[Ruchika]

Hi,
I am working with an Soc with multiple PCIE controllers.
I need to have 2 configured properly.

In uboot I have no problems scanning and discovering what is connected 
to both controllers/PCI bridges.
PCIE1 :
PCIE2:

For both PCIE1/2 uboot sets up the Primary, secondary and Subordinate 
bus numbers to 0,1,1 respectively.

When linux boots up and probes the controllers, PCIE1 is probed and the 
bridge scanned properly but PCIE2 is probed at the bridge but not 
attempted a scan.
I see this message
"pci 0001:02:00.0: bridge configuration invalid ([bus 01-01]), reconfiguring
"

I updated uboot to set the secondary and subordinate numbers to 2 (left 
the primary number to 0) and a subsequent kernel boot scanned the bus 
for PCIE2 successfully.
I found these numbers to be very critical since the device tree blob 
(bus-range) for pci is also based off these.

I'd like to get a good fix and get better understanding of the problem. 
If there are any pointers someone could provide it would be awesome.

Thank you
Regards
Ruchika

-- 
Regards,
Ruchika Kharwar | Validation engineer
Servergy, Inc. | Save Energy. Work Smart. ®
M (832) 276 9309| E ruchika.k@servergy.com
www.servergy.com

questions: second of the 2 pcie controllers does not scan the bus.

[Ruchika]

Hi,
I am working with an p4080 based board. I am trying to get 2 PCIE 
controllers probed properly.

In uboot I have no problems scanning and discovering what is connected 
to both controllers/PCI bridges.

For both PCIE1/2 uboot sets up the Primary, secondary and Subordinate 
bus numbers to 0,1,1 respectively.

When linux boots up and probes the controllers, PCIE1 is probed and the 
bridge scanned properly but PCIE2 is probed at the bridge but not 
attempted a scan.
I see this message
"pci 0001:02:00.0: bridge configuration invalid ([bus 01-01]), reconfiguring
"

I updated uboot to set the secondary and subordinate numbers to 2 (left 
the primary number to 0) and a subsequent kernel boot scanned the bus 
for PCIE2 successfully.
I found these numbers to be very critical since the device tree blob 
(bus-range) for pci is also based off these.

I'd like to get a good fix rather than the uboot hack and get better 
understanding of the problem. If there are any pointers someone could 
provide it would be awesome.

Thank you
Regards
Ruchika

questions: second of the 2 pcie controllers does not scan the bus.

[Ruchika]

Any ideas/pointers anyone ?
Thank you
On 12/6/2013 6:48 PM, Ruchika wrote:
>
> Hi,
> I am working with an p4080 based board. I am trying to get 2 PCIE
> controllers probed properly.
>
> In uboot I have no problems scanning and discovering what is connected
> to both controllers/PCI bridges.
>
> For both PCIE1/2 uboot sets up the Primary, secondary and Subordinate
> bus numbers to 0,1,1 respectively.
>
> When linux boots up and probes the controllers, PCIE1 is probed and the
> bridge scanned properly but PCIE2 is probed at the bridge but not
> attempted a scan.
> I see this message
> "pci 0001:02:00.0: bridge configuration invalid ([bus 01-01]),
> reconfiguring
> "
>
> I updated uboot to set the secondary and subordinate numbers to 2 (left
> the primary number to 0) and a subsequent kernel boot scanned the bus
> for PCIE2 successfully.
> I found these numbers to be very critical since the device tree blob
> (bus-range) for pci is also based off these.
>
> I'd like to get a good fix rather than the uboot hack and get better
> understanding of the problem. If there are any pointers someone could
> provide it would be awesome.
>
> Thank you
> Regards
> Ruchika
>
>
>

Re: questions: second of the 2 pcie controllers does not scan the bus.

[Scott Wood]

On Fri, 2013-12-06 at 18:48 -0600, Ruchika wrote:
> Hi,
> I am working with an p4080 based board. I am trying to get 2 PCIE 
> controllers probed properly.
> 
> In uboot I have no problems scanning and discovering what is connected 
> to both controllers/PCI bridges.
> 
> For both PCIE1/2 uboot sets up the Primary, secondary and Subordinate 
> bus numbers to 0,1,1 respectively.
> 
> When linux boots up and probes the controllers, PCIE1 is probed and the 
> bridge scanned properly but PCIE2 is probed at the bridge but not 
> attempted a scan.
> I see this message
> "pci 0001:02:00.0: bridge configuration invalid ([bus 01-01]), reconfiguring
> "
> 
> I updated uboot to set the secondary and subordinate numbers to 2 (left 
> the primary number to 0) and a subsequent kernel boot scanned the bus 
> for PCIE2 successfully.
> I found these numbers to be very critical since the device tree blob 
> (bus-range) for pci is also based off these.
> 
> I'd like to get a good fix rather than the uboot hack and get better 
> understanding of the problem. If there are any pointers someone could 
> provide it would be awesome.

This is the code that prints that:

        /* Check if setup is sensible at all */
        if (!pass &&
            (primary != bus->number || secondary <= bus->number ||
             secondary > subordinate)) {
                dev_info(&dev->dev, "bridge configuration invalid ([bus %02x-%0
                         secondary, subordinate);
                broken = 1;
        }

Start by printing out more information to determine which of those
checks is failing (e.g. what is primary and bus->number).  If it turns
out that U-Boot is configuring the PCI bus incorrectly, send e-mail to
the U-Boot list.  Be sure to mention what version of Linux and U-Boot
you're using.

-Scott