[PATCH v2 2/3] IRQ/Gic-V3: Change arm-gic-its to support the Mbigen interrupt

majun (F) majun258 at huawei.com
Fri Jun 26 03:28:07 PDT 2015

Hi Marc:

在 2015/6/26 16:44, Marc Zyngier 写道:
> You can then keep your MBI stuff in a separate file, and call into 
> its_msi_prepare.
Thanks for your good suggestion!
I have two questions:

Question 1:

I found the ‘its_msi_preapare ' defined without static.
So,I guess you mean I can call this fucntion directly
from mbigen driver, right?
or I need make the code likes below and leave these code in ITS?

static struct mbigen_domain_ops its_mbigen_ops = {
+	.mbigen_prepare	= its_msi_prepare,

static struct mbigen_domain_info its_mbigen_domain_info = {
	.ops	= &its_mbigen_ops,

Question 2:

@@ -1489,6 +1538,18 @@ static int its_probe(struct device_node *node, struct irq_domain *parent)
 		err = of_pci_msi_chip_add(&its->msi_chip);
 		if (err)
 			goto out_free_domains;
+			its->mbi_chip.domain = its_mbigen_create_irq_domain(node,
+										&its_mbigen_domain_info,
+										its->domain);
+			if (!its->mbi_chip.domain) {
+				err = -ENOMEM;
+				pr_warn_once("ITS:no mbigen chip found\n");
+				goto out_free_mbigen;
+			}
+		}

@@ -1497,6 +1558,9 @@ static int its_probe(struct device_node *node, struct irq_domain *parent)

 	return 0;

+	if (its->mbi_chip.domain)
+		irq_domain_remove(its->mbi_chip.domain);
 	if (its->msi_chip.domain)

What's you opinion about the code above
Leave it in ITS or create the mbi irq domain in mbigen driver?
If I have to create mbi irq domain in mbigen driver,
I need a pointer of its domain.

For this problem, I think i can solve it by using its_nodes’
in mbigen driver *if*
[1] add a member " struct device_node *node" in 'struct its_node'
[2] in 'its_probe' function , add
	its->node = node;
[3] remove the static definition from  'static LIST_HEAD(its_nodes);'

How is you opinion?

Thansks again!

>> Now, all these functions and data structure are defined as static.
>> to use them, I have to remove the 'static' definition and put them
>> in a head file ( create a new head file).
> I don't want to see these functions and structure leaking out of the
> ITS code unless we're absolutely forced to do so.  The above code
> shows you one possible way to solve the problem.

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