MIPS: CPS: Set Status.KX on entry for MIPS64 kernels

If the kernel may make use of 64 bit addresses outside of the
compatibility address space then we need to set KX such that those
accesses can succeed. Do so for MIPS64 kernels.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11201/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/cps-vec.S

@@ -25,6 +25,12 @@
 
 .set noreorder
 
+#ifdef CONFIG_64BIT
+# define STATUS_BITDEPS		ST0_KX
+#else
+# define STATUS_BITDEPS		0
+#endif
+
 	/*
 	 * Set dest to non-zero if the core supports the MT ASE, else zero. If
 	 * MT is not supported then branch to nomt.
@@ -71,7 +77,7 @@ not_nmi:
 	mtc0	t0, CP0_CAUSE
 
 	/* Setup Status */
-	li	t0, ST0_CU1 | ST0_CU0 | ST0_BEV
+	li	t0, ST0_CU1 | ST0_CU0 | ST0_BEV | STATUS_BITDEPS
 	mtc0	t0, CP0_STATUS
 
 	/*