[MIPS] The irq_chip for TX39/TX49 SoCs

Add generic irq_chip for TX39/TX49 SoCs.  This can be replace
jmr3927_irq_irc, tx4927_irq_pic_type and tx4938_irq_pic_type.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/include/asm-mips/txx9irq.h b/include/asm-mips/txx9irq.h
new file mode 100644
index 0000000..1c439e5
--- /dev/null
+++ b/include/asm-mips/txx9irq.h
@@ -0,0 +1,30 @@
+/*
+ * include/asm-mips/txx9irq.h
+ * TX39/TX49 interrupt controller definitions.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#ifndef __ASM_TXX9IRQ_H
+#define __ASM_TXX9IRQ_H
+
+#include <irq.h>
+
+#ifdef CONFIG_IRQ_CPU
+#define TXX9_IRQ_BASE	(MIPS_CPU_IRQ_BASE + 8)
+#else
+#define TXX9_IRQ_BASE	0
+#endif
+
+#ifdef CONFIG_CPU_TX39XX
+#define TXx9_MAX_IR 16
+#else
+#define TXx9_MAX_IR 32
+#endif
+
+void txx9_irq_init(unsigned long baseaddr);
+int txx9_irq(void);
+int txx9_irq_set_pri(int irc_irq, int new_pri);
+
+#endif /* __ASM_TXX9IRQ_H */