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authorKyle Moffett <Kyle.D.Moffett@boeing.com>2011-12-02 06:28:07 +0000
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>2011-12-07 13:43:09 +1100
commit09dc34a95bfbc6062e1e7de0b96175480924aea8 (patch)
treed21a67d125278304324415ae2b7c23aa056584dc /arch/powerpc/sysdev
parentc51242e7080d2265761de309cdea222d7e27bdfe (diff)
powerpc/mpic: Add in-core support for cascaded MPICs
The Cell and PowerMac platforms use virtually identical cascaded-IRQ setup code, so just merge it into the core. Ideally this code would trigger automatically when an MPIC device-node specifies an "interrupts" property, perhaps even enabling MPIC_SECONDARY along the way. Unfortunately, Benjamin Herrenschmidt has had bad experiences in the past with the quality of Apple PowerMac device-trees, so to be safe we will only try to parse out an IRQ if the MPIC_SECONDARY flag is set by the caller. Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/sysdev')
-rw-r--r--arch/powerpc/sysdev/mpic.c30
1 files changed, 28 insertions, 2 deletions
diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index 76110608543..4e9ccb1015d 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -1111,6 +1111,22 @@ static int mpic_host_xlate(struct irq_host *h, struct device_node *ct,
return 0;
}
+/* IRQ handler for a secondary MPIC cascaded from another IRQ controller */
+static void mpic_cascade(unsigned int irq, struct irq_desc *desc)
+{
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ struct mpic *mpic = irq_desc_get_handler_data(desc);
+ unsigned int virq;
+
+ BUG_ON(!(mpic->flags & MPIC_SECONDARY));
+
+ virq = mpic_get_one_irq(mpic);
+ if (virq != NO_IRQ)
+ generic_handle_irq(virq);
+
+ chip->irq_eoi(&desc->irq_data);
+}
+
static struct irq_host_ops mpic_host_ops = {
.match = mpic_host_match,
.map = mpic_host_map,
@@ -1402,8 +1418,7 @@ void __init mpic_set_default_senses(struct mpic *mpic, u8 *senses, int count)
void __init mpic_init(struct mpic *mpic)
{
- int i;
- int cpu;
+ int i, cpu;
BUG_ON(mpic->num_sources == 0);
@@ -1488,6 +1503,17 @@ void __init mpic_init(struct mpic *mpic)
GFP_KERNEL);
BUG_ON(mpic->save_data == NULL);
#endif
+
+ /* Check if this MPIC is chained from a parent interrupt controller */
+ if (mpic->flags & MPIC_SECONDARY) {
+ int virq = irq_of_parse_and_map(mpic->node, 0);
+ if (virq != NO_IRQ) {
+ printk(KERN_INFO "%s: hooking up to IRQ %d\n",
+ mpic->node->full_name, virq);
+ irq_set_handler_data(virq, mpic);
+ irq_set_chained_handler(virq, &mpic_cascade);
+ }
+ }
}
void __init mpic_set_clk_ratio(struct mpic *mpic, u32 clock_ratio)