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3 commits

Author SHA1 Message Date
Rich Felker
c024f06b3d irqchip/jcore: Fix lost per-cpu interrupts
The J-Core AIC does not have separate interrupt numbers reserved for
cpu-local vs global interrupts. Instead, the driver requesting the irq
is expected to know whether its device uses per-cpu interrupts or not.
Previously it was assumed that handle_simple_irq could work for both
cases, but it intentionally drops interrupts for an irq number that
already has a handler running. This resulted in the timer interrupt
for one cpu being lost when multiple cpus' timers were set for
approximately the same expiration time, leading to stalls. In theory
the same could also happen with IPIs.

To solve the problem, instead of registering handle_simple_irq as the
handler, register a wrapper function which checks whether the irq to
be handled was requested as per-cpu or not, and passes it to
handle_simple_irq or handle_percpu_irq accordingly.

Fixes: 981b58f66c ("irqchip/jcore-aic: Add J-Core AIC driver")
Signed-off-by: Rich Felker <dalias@libc.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: linux-sh@vger.kernel.org
Link: http://lkml.kernel.org/r/f18cec30bc17e3f52e478dd9f6714bfab02f227f.1476390724.git.dalias@libc.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-10-14 14:26:55 +02:00
Wei Yongjun
21118df66c irqchip/jcore-aic: Fix non static symbol warning
Fixes the following sparse warning:

drivers/irqchip/irq-jcore-aic.c:47:12: warning:
 symbol 'aic_irq_of_init' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com>
Link: https://lkml.kernel.org/r/1471706788-27587-1-git-send-email-weiyj.lk@gmail.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2016-08-22 23:08:59 +00:00
Rich Felker
981b58f66c irqchip/jcore-aic: Add J-Core AIC driver
There are two versions of the J-Core interrupt controller in use, aic1
which generates interrupts with programmable priorities, but only
supports 8 irq lines and maps them to cpu traps in the range 17 to 24,
and aic2 which uses traps in the range 64-127 and supports up to 128
irqs, with priorities dependent on the interrupt number. The Linux
driver does not make use of priorities anyway.

For simplicity, there is no aic1-specific logic in the driver beyond
setting the priority register, which is necessary for interrupts to
work at all. Eventually aic1 will likely be phased out, but it's
currently in use in deployments and all released bitstream binaries.

Signed-off-by: Rich Felker <dalias@libc.org>
Link: https://lkml.kernel.org/r/c3b89ef74aaa6477575dbe2d410eb1d182503243.147018b6529.git.dalias@libc.org
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2016-08-08 20:28:11 +00:00