On 11/25/2011 04:28 PM, Jamie Iles :

On Fri, Nov 25, 2011 at 02:51:06PM +0100, Jean-Christophe PLAGNIOL-VILLARD wrote:

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On 22:26 Thu 24 Nov     , Jamie Iles wrote:

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Hi Nicolas,
On Thu, Nov 24, 2011 at 10:56:27PM +0100, Nicolas Ferre wrote:

[...]

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+#if defined(CONFIG_OF)
+static struct of_device_id aic_ids[]  = {
+	{ .compatible = "atmel,at91rm9200-aic" },
+	{ /*sentinel*/ }
+};
+
+static int __init at91_aic_of_init(void)
+{
+	struct device_node *np;
+
+	np = of_find_matching_node(NULL, aic_ids);
+	if (np == NULL)
+		return -ENODEV;
+
+	at91_aic_base = of_iomap(np, 0);
+	at91_aic_domain.of_node = np;

I think this needs to be:

	at91_aic_domain.of_node = of_node_get(np);

to keep the reference count.

Well, in fact the of_find_matching_node() function already indent the 
ref. count...

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+	/* Keep refcount of the node */

... That is why I added this comment ^^

But maybe for sake of clarity, I may have used what you propose anyway. 
What it your opinion?

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+
+	return 0;
+}
+#else
+static int __init at91_aic_of_init(void)
+{
+	return -ENOSYS;
+}
+#endif

I think it's preferred if you use of_irq_init() here as it can handle
the ordering of IRQ controllers.  There are GIC and VIC bindings in
-next that use this and provide a way for non-DT platforms to still use
the drivers.

which is the case here as if the of_init fail we failback to the non-dt init

and this IP is AT91 only

Right, but it's not using the of_irq_init() interface which is the
standard way of registering interrupt controllers and will correctly
dependencies for you.

So if you could have something like:

void __init __at91_aic_init(unsigned int priority[NR_AIC_IRQS],
			    void __iomem *regs,
			    struct device_node *np)
{
	/*
	 * Do all of the writes to the AIC itself and configure
	 * the IRQ domain.
	 */
}

void __init at91_aic_init(unsigned int priority[NR_AIC_IRQS])
{
	void __iomem *base = ioremap(AT91_AIC, 512);

	__at91_aic_init(priority, base, NULL);
}

int __init at91_aic_of_init(struct device_node *node,
			    struct device_node *parent)
{
	void __iomem *regs = of_iomap(node, 0);

	/*
	 * Get priorities from the DT.  If this was an array of cells
	 * then that should be okay.
	 */
	__at91_aic_init(dt_priorities, regs, node);
}

Then the DT based board initialisation can do:

static const struct of_device_id at91_irq_of_match[] __initconst = {
	{ .compatible = "atmel,at91-aic", .data = at91_aic_of_init },
	{}
};

static void __init at91_of_irq_init(void)
{
	of_irq_init(at91_of_irq_init);
}

That looks nice. I will try to implement this. I will try to figure out 
when of_irq_init() is called compared to the other init_IRQ() function.

Which is consistent with other platforms.  However this does require
that the priorities are encoded in the device-tree, but I guess that's a
good thing anyway isn't it?

That is a annoying point: I do not want to add all this "default" 
priority stuff in the DT. It is kind of useless until we use the 
threaded interrupts everywhere and may bloat the DT...

I will try to find a way to pass the default priority table to the DT 
called function.

Thanks for your review,
-- 
Nicolas Ferre