I'm developing the PCIe controller driver.
It needs to work the PCI device via the PCIe-PCI bridge.
The PCI device supports legacy PCI interrupts only.
The PCIe controller driver can't catch it's legacy PCI interrupts.
I have some questions.
Q1: Does PCIe controller of i.MX8MM support legacy PCI interrupts?
Q2: If PCIe controller of i.MX8MM support legacy PCI interrupts,
which GIC IRQs of i.MX8MM are the Legacy PCI interrupts assigned to?
I tried to use IRQ 122, IRQ 123, IRQ 124, IRQ 125 and IRQ 127.
But the PCIe controller driver couldn't cache the Legacy PCI interrupts.
Q3: If PCIe controller of i.MX8MM support legacy PCI interrupts,
Could you provide information about using legacy PCI interrupts?
I read i.MX8MM Reference Manual(IMX8MMRM.pdf). But I couldn't find it.
Solved! Go to Solution.
Hi,
Q1: Does PCIe controller of i.MX8MM support legacy PCI interrupts?
Yes, it does.
Q2: IRQ 122, IRQ 123, IRQ 124, IRQ 125 and IRQ 127 are used for PCIe interrupts, so no problem.
Q3: If PCIe controller of i.MX8MM support legacy PCI interrupts, Could you provide information about using legacy PCI interrupts?
You should add "pci=nomsi" to linux command line , which will cause all pcie device to work in legacy PCI interrupts mode. otherwise, msi mode.
Hope above information is helpful to you.
Have a nice day!
B.R,
Weidong
Hi,
Q1: Does PCIe controller of i.MX8MM support legacy PCI interrupts?
Yes, it does.
Q2: IRQ 122, IRQ 123, IRQ 124, IRQ 125 and IRQ 127 are used for PCIe interrupts, so no problem.
Q3: If PCIe controller of i.MX8MM support legacy PCI interrupts, Could you provide information about using legacy PCI interrupts?
You should add "pci=nomsi" to linux command line , which will cause all pcie device to work in legacy PCI interrupts mode. otherwise, msi mode.
Hope above information is helpful to you.
Have a nice day!
B.R,
Weidong
Thank you for your advice.
I can execute linux in no-msi mode.
And linux behavior helped my debugging.
At result developping drive can catch legacy PCI interrupt.