sh: intc: userimask support.
This adds support for hardware-assisted userspace irq masking for
special priority levels. Due to the SR.IMASK interactivity, only some
platforms implement this in hardware (including but not limited to
SH-4A interrupt controllers, and ARM-based SH-Mobile CPUs). Each CPU
needs to wire this up on its own, for now only SH7786 is wired up as an
example.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/drivers/sh/Kconfig b/drivers/sh/Kconfig
new file mode 100644
index 0000000..22c3cda
--- /dev/null
+++ b/drivers/sh/Kconfig
@@ -0,0 +1,13 @@
+config INTC_USERIMASK
+ bool "Userspace interrupt masking support"
+ depends on ARCH_SHMOBILE || (SUPERH && CPU_SH4A)
+ help
+ This enables support for hardware-assisted userspace hardirq
+ masking.
+
+ SH-4A and newer interrupt blocks all support a special shadowed
+ page with all non-masking registers obscured when mapped in to
+ userspace. This is primarily for use by userspace device
+ drivers that are using special priority levels.
+
+ If in doubt, say N.