[POWERPC] pasemi: Implement NMI support

Some PWRficient-based boards have a NMI button that's wired up to a GPIO
as interrupt source. By configuring the openpic accordingly, these get
delivered as a machine check with high priority, instead of as an external
interrupt.

The device tree contains a property "nmi-source" in the openpic node
for these systems, and it's the (hwirq) source for the input.

Also, for these interrupts, the IACK is read from another register than
the regular (MCACK instead), but they are EOI'd as usual. So implement
said function for the mpic driver.

Finally, move a couple of external function defines to include/ instead
of local under sysdev. Being able to mask/unmask and eoi directly saves
us from setting up a dummy irq handler that will never be called.

Signed-off-by: Olof Johansson <olof@lixom.net>
diff --git a/include/asm-powerpc/mpic.h b/include/asm-powerpc/mpic.h
index ae84dde3..e7ac810 100644
--- a/include/asm-powerpc/mpic.h
+++ b/include/asm-powerpc/mpic.h
@@ -23,6 +23,7 @@
 #define		MPIC_GREG_GCONF_RESET			0x80000000
 #define		MPIC_GREG_GCONF_8259_PTHROU_DIS		0x20000000
 #define		MPIC_GREG_GCONF_BASE_MASK		0x000fffff
+#define		MPIC_GREG_GCONF_MCK			0x08000000
 #define MPIC_GREG_GLOBAL_CONF_1		0x00030
 #define		MPIC_GREG_GLOBAL_CONF_1_SIE		0x08000000
 #define		MPIC_GREG_GLOBAL_CONF_1_CLK_RATIO_MASK	0x70000000
@@ -78,6 +79,7 @@
 #define 	MPIC_CPU_WHOAMI_MASK			0x0000001f
 #define MPIC_CPU_INTACK			0x000a0
 #define MPIC_CPU_EOI			0x000b0
+#define MPIC_CPU_MCACK			0x000c0
 
 /*
  * Per-source registers
@@ -141,6 +143,7 @@
 #define TSI108_CPU_WHOAMI		0xffffffff
 #define TSI108_CPU_INTACK		0x00004
 #define TSI108_CPU_EOI			0x00008
+#define TSI108_CPU_MCACK		0x00004 /* Doesn't really exist here */
 
 /*
  * Per-source registers
@@ -183,6 +186,7 @@
 	MPIC_IDX_CPU_WHOAMI,
 	MPIC_IDX_CPU_INTACK,
 	MPIC_IDX_CPU_EOI,
+	MPIC_IDX_CPU_MCACK,
 
 	MPIC_IDX_IRQ_BASE,
 	MPIC_IDX_IRQ_STRIDE,
@@ -344,6 +348,8 @@
 #define MPIC_USES_DCR			0x00000080
 /* MPIC has 11-bit vector fields (or larger) */
 #define MPIC_LARGE_VECTORS		0x00000100
+/* Enable delivery of prio 15 interrupts as MCK instead of EE */
+#define MPIC_ENABLE_MCK			0x00000200
 
 /* MPIC HW modification ID */
 #define MPIC_REGSET_MASK		0xf0000000
@@ -447,10 +453,19 @@
 /* Send a message (IPI) to a given target (cpu number or MSG_*) */
 void smp_mpic_message_pass(int target, int msg);
 
+/* Unmask a specific virq */
+extern void mpic_unmask_irq(unsigned int irq);
+/* Mask a specific virq */
+extern void mpic_mask_irq(unsigned int irq);
+/* EOI a specific virq */
+extern void mpic_end_irq(unsigned int irq);
+
 /* Fetch interrupt from a given mpic */
 extern unsigned int mpic_get_one_irq(struct mpic *mpic);
-/* This one gets to the primary mpic */
+/* This one gets from the primary mpic */
 extern unsigned int mpic_get_irq(void);
+/* Fetch Machine Check interrupt from primary mpic */
+extern unsigned int mpic_get_mcirq(void);
 
 /* Set the EPIC clock ratio */
 void mpic_set_clk_ratio(struct mpic *mpic, u32 clock_ratio);