genirq: Add a new generic IPI reservation code to irq core
Add a generic mechanism to dynamically allocate an IPI. Depending on the
underlying implementation this creates either a single Linux irq or a
consective range of Linux irqs. The Linux irq is used later to send IPIs to
other CPUs.
[ tglx: Massaged the code and removed the 'consecutive mask' restriction for
the single IRQ case ]
Signed-off-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: <jason@lakedaemon.net>
Cc: <marc.zyngier@arm.com>
Cc: <jiang.liu@linux.intel.com>
Cc: <ralf@linux-mips.org>
Cc: <linux-mips@linux-mips.org>
Cc: <lisa.parratt@imgtec.com>
Cc: Qais Yousef <qsyousef@gmail.com>
Link: http://lkml.kernel.org/r/1449580830-23652-9-git-send-email-qais.yousef@imgtec.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/irq.h b/include/linux/irq.h
index a32b47f..95f4f66 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -940,4 +940,7 @@
return readl(gc->reg_base + reg_offset);
}
+/* Contrary to Linux irqs, for hardware irqs the irq number 0 is valid */
+#define INVALID_HWIRQ (~0UL)
+
#endif /* _LINUX_IRQ_H */