lkml.org 
[lkml]   [2016]   [Aug]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/2] irqchip: mips-gic: Implement activate op for device domain
Date
If an IRQ is setup using __setup_irq(), which is used by the
request_irq() family of functions, and we are using an SMP kernel then
the affinity of the IRQ will be set via setup_affinity() immediately
after the IRQ is enabled. This call to gic_set_affinity() will lead to
the interrupt being mapped to a VPE. However there are other ways to use
IRQs which don't cause affinity to be set, for example if it is used to
chain to another IRQ controller with irq_set_chained_handler_and_data().
The irq_set_chained_handler_and_data() code path will enable the IRQ,
but will not trigger a call to gic_set_affinity() and in this case
nothing will map the interrupt to a VPE, meaning that the interrupt is
never received.

Fix this by implementing the activate operation for the GIC device IRQ
domain, using gic_shared_irq_domain_map() to map the interrupt to the
correct pin of cpu 0.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: c98c1822ee13 ("irqchip/mips-gic: Add device hierarchy domain")
Cc: stable@vger.kernel.org # v4.6+
---
This one would be great to get in ASAP, for v4.8 if possible, as it breaks
certain uses of GIC interrupts.
---
drivers/irqchip/irq-mips-gic.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/irqchip/irq-mips-gic.c b/drivers/irqchip/irq-mips-gic.c
index d7ec984..d3ef0fc 100644
--- a/drivers/irqchip/irq-mips-gic.c
+++ b/drivers/irqchip/irq-mips-gic.c
@@ -893,10 +893,17 @@ void gic_dev_domain_free(struct irq_domain *d, unsigned int virq,
return;
}

+static void gic_dev_domain_activate(struct irq_domain *domain,
+ struct irq_data *d)
+{
+ gic_shared_irq_domain_map(domain, d->irq, d->hwirq, 0);
+}
+
static struct irq_domain_ops gic_dev_domain_ops = {
.xlate = gic_dev_domain_xlate,
.alloc = gic_dev_domain_alloc,
.free = gic_dev_domain_free,
+ .activate = gic_dev_domain_activate,
};

static int gic_ipi_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
--
2.9.3
\
 
 \ /
  Last update: 2016-09-17 09:57    [W:0.055 / U:1.620 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site