Multiprocessor support

[stlankes]

Hello,

do you test if your crate is able to support a multiprocessor configuration?

In my case, I configure the first processor as followed:

let mut gic = unsafe {
        GicV3::new(
	       gicd_address.as_mut_ptr(),
	       gicr_address.as_mut_ptr(),
	       2,
	       false,
	)
};

gic.setup(0);
let sgi_intid = IntId::sgi(3);
gic.set_interrupt_priority(sgi_intid, Some(0), 0x00);
gic.enable_interrupt(sgi_intid, Some(0), true);

Afterwards, the processor 0 is able to send a software interrupt to itself as followed:

let sgi_intid = IntId::sgi(3);
irq_enable();
GicV3::send_sgi(
    sgi_intid,
    SgiTarget::List {
        affinity3: 0,
        affinity2: 0,
        affinity1: 0,
        target_list: 1 << 0,
    },
);

Processor 0 receives as expected the interrupt.

In addition, the processor 1 initialize the GIC as followed:

gic.init_cpu(1);
let sgi_intid = IntId::sgi(3);
gic.set_interrupt_priority(sgi_intid, Some(0), 0x00);
gic.enable_interrupt(sgi_intid, Some(0), true);
irq_enable();

Now, processor 0 wants to send an interrupt to processor 1 as followed:

let sgi_intid = IntId::sgi(3);
irq_enable();
GicV3::send_sgi(
    sgi_intid,
    SgiTarget::List {
        affinity3: 0,
        affinity2: 0,
        affinity1: 0,
        target_list: 1 << 1,
    },
);

Processor 1 doesn't receive any interrupt. Do I misunderstand your interface?

[qwandor]

This should work, I'll see if I can reproduce your issue.

[stlankes]

My mistake... Also core 1 has to use gic.setup(1) instead of gic.init_cpu(1). You crate works also in our kernel

[qwandor]

My mistake... Also core 1 has to use gic.setup(1) instead of gic.init_cpu(1). You crate works also in our kernel

That shouldn't be necessary, but the setup method is currently a bit of a weird mix of different things. I'll try to clean that up.

[stlankes]

If you are interested, I used your crate for hermit-os/kernel#1705

I forgot also to use GicV3::set_priority_mask(0xff); on the second core...

[qwandor]

Nice!