On 12/09/2011 10:06 AM, Cousson, Benoit wrote:

On 12/9/2011 4:22 PM, Rob Herring wrote:

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On 12/09/2011 08:52 AM, Cousson, Benoit wrote:

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On 12/9/2011 2:20 PM, Rob Herring wrote:

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On 12/08/2011 08:59 AM, Cousson, Benoit wrote:

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On 12/7/2011 10:20 PM, Rob Herring wrote:

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On 12/07/2011 02:50 PM, Benoit Cousson wrote:

[...]

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+#ifdef CONFIG_OF
+int __init intc_of_init(struct device_node *node, struct
device_node
*parent)
+{
+    struct resource res;
+    u32 nr_irqs;
+
+    if (WARN_ON(!node))
+        return -ENODEV;
+
+    if (of_address_to_resource(node, 0,&res)) {
+        WARN(1, "unable to get intc registers\n");
+        return -EINVAL;
+    }
+
+    if (of_property_read_u32(node, "ti,intc-size",&nr_irqs)) {
+        WARN(1, "unable to get intc-size\n");
+        return -EINVAL;

There is no default value that makes sense?

So far we have 96 or 128, so I can put 96 as a default and just
keep the
warning without returning an error.

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+    }
+
+    omap_init_irq(res.start, nr_irqs);
+    irq_domain_add_simple(node, 0);

Have you read the NO_IRQ thread...

Yeah, I tried, but that's a long email thread with some unclear
conclusion...
The point is that the few users of that API today are using 0 as a
base
as well, so I thought it was still valid.

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Is 0 ever a valid interrupt for a driver? If so, you must not use
0 for
the base. I would pick 16 to skip over legacy ISA irqs.

I do not have any 0 interrupts right now, my concern is that I still
have some legacy non-DT drivers that expect the previous hwirq = irq
mapping.

I guess it depends how easily you can shift all the irq defines. You
allow specifying the base so that you can set it to 0 for non-DT and -1
(dynamic allocation) for DT.

The issue, is that the IRQs are not defined anymore but hard coded in
the hwmod database. And the idea is that this is reflecting exactly the
hwirq from the spec, so I do not want to add any artificial offset for
the domain in the original data.

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irqdomains should always be enabled regardless of CONFIG_OF. So
either
you can leave it as is if OF is always enabled for OMAP, or you
should
move domain setup into omap_init_irq.

OK, but it looks like I cannot really modify the current INTC to DT
without having fully adapted the OMAP drivers to use
irq_of_parse_and_map. Or did I miss something?

No, the drivers should not need to be modified as long as they get the
irq's from platform device resources. You just want to make sure the
INTC has no knowledge of it's irq base so it can change.

OK, the driver will not have to change but the IRQ value will not be the
same in the case of DT since it will use the irq_create_of_mapping.

Currently, the driver IRQ resource is 7 for example for the twl, this is
the hwirq (= irq). If I use a domain with a base of 16, the resource
will still be 7 except if the resource is created from OF, then it will
be 23.

The only way I have today to maintain the legacy drivers to work without
hacking the OMAP resource code is to keep the base_irq at 0.

For non-DT case, that is fine. It should not be hard to support 0 for
legacy and !0 for DT.

Mmm, I'm probably missing something here.

My point is that even in the DT case I do have some devices that are
initialized without DT for the moment and thus cannot get access to the
interrupt-controller node and then cannot retrieve the domain information.

How can I ensure the proper hwirq -> irq translation then for such devices?
Only the one created by DT will have the correct irq number.

Okay, I missed that aspect of it. So I guess 0 base is fine for now.

Rob

Adding some hacks to add a +16 is clearly possible, but that will be a
dirty hacks in the OMAP core code that will have to be removed later. So
I'd rather keep the domain with a 0 offset to avoid all these temporary
hacks.

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Since I do not have any hwirq at 0 so far, is it a big deal to keep the
base_irq at 0 for the moment?
It will be easier to transition to DT that way without breaking the
existing drivers.

As long as it is trivial to change later. I'm afraid that if it is not
changed, then we won't know if it is trivial.

As soon as every devices are initialized from DT, the irq_base will
become transparent, since both the IRQ handler and the IRQ resource will
use the irq_domain_to_irq to get the irq from the hwirq. At that time
adding 16 will then be straightforward.
That's why I prefer that approach which is the one that generate the
minimal temporary effort.

Regards,
Benoit