From 09dc34a95bfbc6062e1e7de0b96175480924aea8 Mon Sep 17 00:00:00 2001 From: Kyle Moffett Date: Fri, 2 Dec 2011 06:28:07 +0000 Subject: 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 Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/sysdev/mpic.c | 30 ++++++++++++++++++++++++++++-- 1 file changed, 28 insertions(+), 2 deletions(-) (limited to 'arch/powerpc/sysdev') diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c index 76110608543a..4e9ccb1015de 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) -- cgit v1.2.3