topic i.MX6Q PCIe error in i.MX Processors

i.MX6Q PCIe error

jimmyli — Fri, 04 Sep 2020 10:05:30 GMT

Hi,

Our customer is debugging PCIe communitcation with other device, it is a problem happened that we can't solve the problem.

Hope you can help us to solve it !!!

Thanks very much.

--Platform: MCIMX6Q-SDB

--Linux ver: L4.1.15 dtb: imx6q-sabresd.dtb

--Question:

PCIe device can be recognized, and probes our PCIe driver. But the problem happens when PCIe driver request MSI interrupt from pci_msi_setup_msi_irqs, return -28. Our PCIe device needs 15 interrupts.

Re: i.MX6Q PCIe error

weidong_sun — Tue, 08 Sep 2020 03:37:17 GMT

Hi Jimmy,

you need to select MSI in kernel.

See drivers/pci/Kconfig

.......

config PCI_MSI
bool "Message Signaled Interrupts (MSI and MSI-X)"
depends on PCI
select GENERIC_MSI_IRQ
help
This allows device drivers to enable MSI (Message Signaled
Interrupts). Message Signaled Interrupts enable a device to
generate an interrupt using an inbound Memory Write on its
PCI bus instead of asserting a device IRQ pin.

Use of PCI MSI interrupts can be disabled at kernel boot time
by using the 'pci=nomsi' option. This disables MSI for the
entire system.

If you don't know what to do here, say Y.

config PCI_MSI_IRQ_DOMAIN
bool
depends on PCI_MSI
select GENERIC_MSI_IRQ_DOMAIN

......

Have a nice day!

Weidong

Re: i.MX6Q PCIe error

jimmyli — Tue, 08 Sep 2020 09:50:19 GMT

Hi Weidong,

I don't know how to fix the problem. Hope you can show me how to fix it.

Thanks very much.