Can't understand /proc/interrupts output for GICv3 case

Chan Kim ckim at
Mon Apr 11 10:15:57 EDT 2022

> > > What bus type is your driver written for?
> > >
> > That sounds very logical. In my case I added it to system bus.
> What exactly do you mean by "system bus"?
I meant 'sysbus' in qemu code that I showed in the qemu code.
And I think it's the CPU bus.

> Where is your kernel code?
This is the init function of my char driver. I thought if the struct cdev
contains struct device, maybe I could use the struct device's of_node to
call of_irq_get but it doesn't.
And I remember I've seen the cdev in usually contained in the driver data of
platform driver(?). Can I implement platform driver in kernel module form? 
Below is the char driver init code. Currently it's request_irq(6, ... ) but
I want to know out the number 6 using program. If you have any advice,
please tell me.

static int __init chr_driver_init(void)
	int ret;
	/* Allocating Major number */
	if ((alloc_chrdev_region(&dev, 0, 1, "axpu_Dev")) < 0) {
		printk(KERN_INFO"Cannot allocate the major number..\n");
		return -1;

	printk(KERN_INFO"Major = %d Minor = %d..\n",MAJOR(dev),MINOR(dev));
	/* creating cdev structure */
	cdev_init(&axpu_cdev, &fops);
	axpu_cdev.owner = THIS_MODULE;

	/* Adding character device to the system */
	if ((cdev_add(&axpu_cdev,dev,1)) < 0) {
		printk(KERN_INFO "Cannot add the device to the
		goto r_class;

	/* creating struct class */
	if ((dev_class = class_create(THIS_MODULE, "axpu_class")) == NULL) {
		printk(KERN_INFO "cannot create the struct class...\n");
		goto r_class;

	/* for interrupt test !! */
	/*  for vanilla work-around.. already made by mkdev */
	if ((device_create(dev_class, NULL, dev, NULL, "axpu_device")) ==
		printk(KERN_INFO "cannot create the device ..\n");
		goto r_device;
	else { printk(KERN_INFO "axpu_device created..\n"); }

	vaddr = ioremap(AXPU_BASE, 0x80000);	
		printk(KERN_INFO"Failed to map the address.\n");
		return 1;
	printk("----- AXPU_BASE mapped at vaddr = %px\n", vaddr);

	ret = request_irq(6, axpu_irq_handler, IRQF_SHARED, "axpu_irq",
	printk("request_irq returned %d\n", ret); // -EINVAL
	printk(KERN_INFO "Device driver inserted ..done properly..\n");
	return 0;

r_device :

r_class :
	return -1;

Thank you.
Chan Kim

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