xtensa: use register window specific opcodes only when present

xtensa core may be configured without register windows support, don't
use register window specific opcodes in that case. Use window register
specific opcodes to initialize hardware or reset core to a known state
regardless of the chosen ABI.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

arch/xtensa/boot/boot-elf/bootstrap.S

@@ -42,12 +42,14 @@ _bootparam:
 
 	.align  4
 _SetupMMU:
+#if XCHAL_HAVE_WINDOWED
 	movi	a0, 0
 	wsr	a0, windowbase
 	rsync
 	movi	a0, 1
 	wsr	a0, windowstart
 	rsync
+#endif
 	movi	a0, 0x1F
 	wsr	a0, ps
 	rsync

arch/xtensa/boot/boot-redboot/bootstrap.S

@@ -56,13 +56,13 @@ _start:
 	movi	a4, 1
 	wsr	a4, ps
 	rsync
-
+#if XCHAL_HAVE_WINDOWED
 	rsr	a5, windowbase
 	ssl	a5
 	sll	a4, a4
 	wsr	a4, windowstart
 	rsync
-
+#endif
 	movi	a4, KERNEL_PS_WOE_MASK
 	wsr	a4, ps
 	rsync

arch/xtensa/kernel/align.S

@@ -58,7 +58,9 @@
  *  BE  shift left / mask 0 0 X X
  */
 
+#if XCHAL_HAVE_WINDOWED
 #define UNALIGNED_USER_EXCEPTION
+#endif
 
 #if XCHAL_HAVE_BE
 

arch/xtensa/kernel/entry.S

@@ -940,12 +940,14 @@ unrecoverable_text:
 
 ENTRY(unrecoverable_exception)
 
+#if XCHAL_HAVE_WINDOWED
 	movi	a0, 1
 	movi	a1, 0
 
 	wsr	a0, windowstart
 	wsr	a1, windowbase
 	rsync
+#endif
 
 	movi	a1, KERNEL_PS_WOE_MASK | LOCKLEVEL
 	wsr	a1, ps

arch/xtensa/kernel/head.S

@@ -67,11 +67,13 @@ _SetupOCD:
 	 * xt-gdb to single step via DEBUG exceptions received directly
 	 * by ocd.
 	 */
+#if XCHAL_HAVE_WINDOWED
 	movi	a1, 1
 	movi	a0, 0
 	wsr	a1, windowstart
 	wsr	a0, windowbase
 	rsync
+#endif
 
 	movi	a1, LOCKLEVEL
 	wsr	a1, ps