Am Montag, den 28.03.2016, 15:06 -0700 schrieb Tim Harvey:

On Mon, Mar 28, 2016 at 2:30 PM, Fabio Estevam [off-list ref] wrote:

quoted

On Mon, Mar 28, 2016 at 5:42 PM, Tim Harvey [off-list ref] wrote:

quoted

Fabio,

ok - I'll respond there as I agree with the patch but not the wording
of the commit (It's Gateworks 'Ventana' using IMX6 not Laguna and we
do define the polarity properly as active-low in Ventana dt's). It is
the fact that the gpio polarity has the wrong logic level that breaks
Ventana.

Ok, I will change the wording in v2.

quoted

However, there seems to be another regression in 4.5 that's keeping
PCI working for me and I'm still bisecting that (using 802.11n access
points to test). Can you confirm that PCI works in v4.5 on IMX6 boards
with only 5c5fb40de8f14391a1238db05cef88754faf9229 reverted?

On imx6qdl-sabresd.dtsi the PCI reset gpio polarity is set to high,
which is not correct, so the Wifi card could be detected even with
5c5fb40de8f. So two errors in sequence and PCI still works on this
board :-)

ouch - two wrongs did make a right!

It's not too easy to tell how many IMX6 boards incorrectly specify
their reset-gpio polarity. I don't know what the best way to determine
what boards use the IMX6 pcie host controller. Is there a dtc usage
that will display the compiled dtb's then we grep out 'compatible =
"fsl,imx6q-pcie"' to at least get the list of boards to inspect? I'm
curious if its just one or two boards that incorrectly specify the
polarity of their PCI reset.

I would suspect that most boards specify the reset polarity the wrong
way around. Fixing this without breaking DT stability is hard. OTOH we
could just argue that the system description in DT is wrong and needs to
be fixed.

quoted

I don't have access to the board at the moment, but the only test I
did was to see that the Wifi card got detected. I haven't really tried
to communicate via Wifi.

I figured out it was the change to enable CONFIG_PCI_MSI in v4.5 that
is causing interrupts to fail for me.

Is this working with v4.4 and PCI_MSI enabled? I'm sure I've tested MSI
IRQs before enabling them in the defconfig and they have been working
for me for a long time before that. Tested with i210 on Gateworks
Ventana.

Lucas, the case that is failing for me is when I have 4 miniPCI radios
behind a PCIe->PCI bridge. In this case the radios get legacy
INTA/B/C/D mapped to them correctly from what I can tell (GIC
123/122/121/120 swizzled appropriately), but those interrupts never
fire. I don't think this case is necessarily a regression, I'm not
clear that it has ever worked. In fact I can't seem to come up with a
scenario where the MSI irq is firing either: IMX6->ath9k radio (no
bridge) with MSI doesn't fire the PCI-MSI interrupt or the GPC 123
interrupt that gets mapped to it via the driver. Any ideas what can be
going on here?

Please test if MSI IRQs work with v4.4. I'll take a look at this later
today.

Regards,
Lucas