On 16/03/2017 16:40, Mason wrote:
> Here is my current DT:
>
> msi0: msi@2e080 {
> compatible = "sigma,msi";
> reg = <0x2e04c 0x40>;
> interrupt-parent = <&irq0>;
> interrupts = <55 IRQ_TYPE_LEVEL_HIGH>;
> msi-controller;
> num-vectors = <32>;
> };
>
> pcie@30000000 {
> compatible = "sigma,smp8759-pcie";
> reg = <0x30000000 SZ_4M>, <0x2e02c 4>;
> device_type = "pci";
> bus-range = <0 3>;
> #size-cells = <2>;
> #address-cells = <3>;
> #interrupt-cells = <1>;
> ranges = <0x02000000 0x0 0x00400000 0x30400000 0x0 SZ_60M>;
> msi-parent = <&msi0>;
> interrupt-parent = <&irq0>;
> interrupts = <54 IRQ_TYPE_LEVEL_HIGH>;
> };
>
>
> I traced the action into pdev_fixup_irq()
> which calls of_irq_parse_and_map_pci()
>
> How do I tell Linux that
> - All the legacy PCI interrupts are muxed to a single line
> - And this line is routed to system interrupt 54
>
> Ooooooh... Wait...
>
> Is this what interrupt-map is used for?
>
> http://elinux.org/Device_Tree_Usage#Advanced_Interrupt_Mapping
I added this to my pcie@30000000 node:
interrupt-map = <0 0 0 1 &irq0 54 IRQ_TYPE_LEVEL_HIGH>;
to map INTA to system IRQ 54.
And now it works much better :-)
# cat /proc/interrupts
CPU0
19: 1529 GIC-0 29 Edge twd
20: 125 irq0 1 Level serial
22: 0 irq0 54 Level tutu, xhci-hcd:usb1
About shared ISRs. Are they supposed to return IRQ_HANDLED
if and only if they handled something?
Will that stop the next ISR from being called?
I guess if two interrupts fire at the same time, we'll
just take two separate exceptions?
Regards.
