问题
I am currently implementing a PCIE endpoint device in xilinx PFGA, and have some problem regards to the interrupt.
when the driver init, it map the interrupt to IRQ 32
[ 1078.938669] alloc irq_desc for 32 on node -1
[ 1078.938670] alloc kstat_irqs on node -1
[ 1078.938675] pci 0000:06:00.0: PCI INT A -> GSI 32 (level, low) -> IRQ 32
However, when the interrupt fires,
[ 1134.850064] irq 16: nobody cared (try booting with the "irqpoll" option)
[ 1134.850067] Pid: 0, comm: swapper Tainted: P 2.6.32-5-amd64 #1
[ 1134.850069] Call Trace:
[ 1134.850070] <IRQ> [<ffffffff81095d89>] ? __report_bad_irq+0x30/0x7d
.
.
.
[ 1134.850119] handlers:
[ 1134.850120] [<ffffffffa0e7935e>] (azx_interrupt+0x0/0x11d [snd_hda_intel])
[ 1134.850124] Disabling IRQ #16
The irq seems to be routed to to another pin IRQ #16. And I used the PCIe msi interrupt. What could cause this problem?
回答1:
I think u maybe using ML555 board. This is a website about PCIE driver on ML555. Luckily it's still alive. https://asim.csail.mit.edu/redmine/projects/leap-platforms/repository/show/trunk/drivers/linux/platforms/htg-pcie-virtex5/src I also meet some obstacle about driver of pcie device. So we can exchange about that.
回答2:
I've run into similar problems.
1) Chris said in his comment, make sure you implement the MSI registers in PCI configuration space. These registers are written by the BIOS/OS to tell the hardware what value to write to which address for the MSI interrupt.
2) Make sure that the PCIE endpoint (pcie_7x?) has the address of those registers configured. 4 registers are required per interrupt. The address given to coregen is a 16-bit word address.
Hope this helps.
来源：https://stackoverflow.com/questions/14217311/pcie-interrupt-routing