powerpc/kexec: make masking/disabling interrupts generic

Right now just the kexec crash pathway turns turns off the interrupts.
Pull that out and make a generic version for use elsewhere

Signed-off-by: Matthew McClintock <msm@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

arch/powerpc/include/asm/kexec.h

@@ -91,6 +91,7 @@ extern void machine_kexec_simple(struct kimage *image);
 extern void crash_kexec_secondary(struct pt_regs *regs);
 extern int overlaps_crashkernel(unsigned long start, unsigned long size);
 extern void reserve_crashkernel(void);
+extern void machine_kexec_mask_interrupts(void);
 
 #else /* !CONFIG_KEXEC */
 static inline int kexec_sr_activated(int cpu) { return 0; }

arch/powerpc/kernel/crash.c

@@ -414,18 +414,7 @@ void default_machine_crash_shutdown(struct pt_regs *regs)
 	crash_kexec_wait_realmode(crashing_cpu);
 #endif
 
-	for_each_irq(i) {
-		struct irq_desc *desc = irq_to_desc(i);
-
-		if (!desc || !desc->chip || !desc->chip->eoi)
-			continue;
-
-		if (desc->status & IRQ_INPROGRESS)
-			desc->chip->eoi(i);
-
-		if (!(desc->status & IRQ_DISABLED))
-			desc->chip->shutdown(i);
-	}
+	machine_kexec_mask_interrupts();
 
 	/*
 	 * Call registered shutdown routines savely.  Swap out

arch/powerpc/kernel/machine_kexec.c

@@ -14,10 +14,34 @@
 #include <linux/threads.h>
 #include <linux/memblock.h>
 #include <linux/of.h>
+#include <linux/irq.h>
+
 #include <asm/machdep.h>
 #include <asm/prom.h>
 #include <asm/sections.h>
 
+void machine_kexec_mask_interrupts(void) {
+	unsigned int i;
+
+	for_each_irq(i) {
+		struct irq_desc *desc = irq_to_desc(i);
+
+		if (!desc || !desc->chip)
+			continue;
+
+		if (desc->chip->eoi &&
+		    desc->status & IRQ_INPROGRESS)
+			desc->chip->eoi(i);
+
+		if (desc->chip->mask)
+			desc->chip->mask(i);
+
+		if (desc->chip->disable &&
+		    !(desc->status & IRQ_DISABLED))
+			desc->chip->disable(i);
+	}
+}
+
 void machine_crash_shutdown(struct pt_regs *regs)
 {
 	if (ppc_md.machine_crash_shutdown)

arch/powerpc/kernel/machine_kexec_32.c

@@ -39,6 +39,10 @@ void default_machine_kexec(struct kimage *image)
 	/* Interrupts aren't acceptable while we reboot */
 	local_irq_disable();
 
+	/* mask each interrupt so we are in a more sane state for the
+	 * kexec kernel */
+	machine_kexec_mask_interrupts();
+
 	page_list = image->head;
 
 	/* we need both effective and real address here */