[PATCH v3 1/2] irq: add irq_domain support to generic-chip

[Shawn Guo]

On Mon, Jan 30, 2012 at 11:31:38AM -0600, Rob Herring wrote:
...
> +#ifdef CONFIG_IRQ_DOMAIN
> +static int irq_gc_irq_domain_match(struct irq_domain *d, struct device_node *np)
> +{
> +	struct irq_chip_generic *gc;
> +
> +	if (d->of_node != NULL && d->of_node == np) {
> +		list_for_each_entry(gc, &gc_list, list) {
> +			if ((gc == d->host_data) && (d == gc->domain))
> +				return 1;
> +		}
> +	}

IIRC, we talked about this a little bit, but I'm still unsure how this
works for imx5 tzic case, where we have the same one tzic device_node
for 4 irqdomains representing 128 irq lines.  It seems to me the match
function here will always find the first irqdomain of the 4 for any
of those 128 tzic irqs.

The following is my code change against your branch for testing.  Am I
missing anything?

8<---
diff --git a/arch/arm/mach-imx/imx51-dt.c b/arch/arm/mach-imx/imx51-dt.c
index e1b5edf..45abf11 100644
--- a/arch/arm/mach-imx/imx51-dt.c
+++ b/arch/arm/mach-imx/imx51-dt.c
@@ -44,13 +44,6 @@ static const struct of_dev_auxdata
imx51_auxdata_lookup[] __initconst = {
        { /* sentinel */ }
 };

-static int __init imx51_tzic_add_irq_domain(struct device_node *np,
-                               struct device_node *interrupt_parent)
-{
-       irq_domain_add_legacy(np, 32, 0, 0, &irq_domain_simple_ops, NULL);
-       return 0;
-}
-
 static int __init imx51_gpio_add_irq_domain(struct device_node *np,
                                struct device_node *interrupt_parent)
 {
@@ -63,7 +56,6 @@ static int __init imx51_gpio_add_irq_domain(struct
device_node *np,
 }

 static const struct of_device_id imx51_irq_match[] __initconst = {
-       { .compatible = "fsl,imx51-tzic", .data = imx51_tzic_add_irq_domain, },
        { .compatible = "fsl,imx51-gpio", .data = imx51_gpio_add_irq_domain, },
        { /* sentinel */ }
 };

diff --git a/arch/arm/plat-mxc/tzic.c b/arch/arm/plat-mxc/tzic.c
index 98308ec..ffb615d 100644
--- a/arch/arm/plat-mxc/tzic.c
+++ b/arch/arm/plat-mxc/tzic.c
@@ -122,7 +122,9 @@ static __init void tzic_init_gc(unsigned int irq_start)
        ct->regs.disable = TZIC_ENCLEAR0(idx);
        ct->regs.enable = TZIC_ENSET0(idx);

-       irq_setup_generic_chip(gc, IRQ_MSK(32), 0, IRQ_NOREQUEST, 0);
+       irq_setup_generic_chip_domain(gc,
+               of_find_compatible_node(NULL, NULL, "fsl,tzic"),
+               IRQ_MSK(32), 0, IRQ_NOREQUEST, 0);
 }

 asmlinkage void __exception_irq_entry tzic_handle_irq(struct pt_regs *regs)
--->8

> +	return 0;
> +}
> +
...
> +void irq_setup_generic_chip_domain(struct irq_chip_generic *gc,
> +			    struct device_node *node, u32 msk,
> +			    enum irq_gc_flags flags, unsigned int clr,
> +			    unsigned int set)
> +{
> +	struct irq_chip_type *ct = gc->chip_types;
> +
> +	if (!node) {
> +		irq_setup_generic_chip(gc, msk, flags, clr, set);
> +		return;
> +	}
> +
> +	raw_spin_lock(&gc_lock);
> +	list_add_tail(&gc->list, &gc_list);
> +	raw_spin_unlock(&gc_lock);
> +
> +	/* Init mask cache ? */
> +	if (flags & IRQ_GC_INIT_MASK_CACHE)
> +		gc->mask_cache = irq_reg_readl(gc->reg_base + ct->regs.mask);
> +
> +	gc->flags = flags;
> +	gc->irq_clr = clr;
> +	gc->irq_set = set;
> +
> +	/* Users of domains should not use irq_base */
> +	if ((int)gc->irq_base > 0)
> +		gc->domain = irq_domain_add_legacy(node, fls(msk),
> +						   gc->irq_base, 0,
> +						   &irq_gc_irq_domain_ops, gc);
> +	else {
> +		gc->irq_base = 0;
> +		gc->domain = irq_domain_add_linear(node, fls(msk),
> +						   &irq_gc_irq_domain_ops, gc);
> +	}

We have 4 generic_chips for tzic with irq_base as 0, 32, 64, 96.  In
this case, we end up with having the first domain as the linear, and
the other 3 as the legacy?

> +}
> +EXPORT_SYMBOL_GPL(irq_setup_generic_chip_domain);
> +#endif

-- 
Regards,
Shawn