[XTENSA] Remove non-rt signal handling

The non-rt signal handling was never really used, so we don't break
anything. This patch also cleans up the signal stack-frame to make
it independent from the processor configuration. It also improves
the method used for controlling single-stepping. We now save and
restore the 'icountlevel' register that controls single stepping
and set or clear the saved state to enable or disable it.

Signed-off-by: Chris Zankel <chris@zankel.net>

include/asm-xtensa/sigcontext.h

@@ -5,21 +5,12 @@
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  *
- * Copyright (C) 2001 - 2003 Tensilica Inc.
+ * Copyright (C) 2001 - 2007 Tensilica Inc.
  */
 
 #ifndef _XTENSA_SIGCONTEXT_H
 #define _XTENSA_SIGCONTEXT_H
 
-#define _ASMLANGUAGE
-#include <asm/processor.h>
-#include <asm/coprocessor.h>
-
-
-struct _cpstate {
-	unsigned char _cpstate[XTENSA_CP_EXTRA_SIZE];
-} __attribute__ ((aligned (XTENSA_CP_EXTRA_ALIGN)));
-
 
 struct sigcontext {
 	unsigned long	oldmask;
@@ -27,18 +18,13 @@ struct sigcontext {
 	/* CPU registers */
 	unsigned long sc_pc;
 	unsigned long sc_ps;
-	unsigned long sc_wmask;
-	unsigned long sc_windowbase;
-	unsigned long sc_windowstart;
 	unsigned long sc_lbeg;
 	unsigned long sc_lend;
 	unsigned long sc_lcount;
 	unsigned long sc_sar;
-	unsigned long sc_depc;
-	unsigned long sc_dareg0;
-	unsigned long sc_treg[4];
-	unsigned long sc_areg[XCHAL_NUM_AREGS];
-	struct _cpstate *sc_cpstate;
+	unsigned long sc_acclo;
+	unsigned long sc_acchi;
+	unsigned long sc_a[16];
 };
 
-#endif /* __ASM_XTENSA_SIGCONTEXT_H */
+#endif /* _XTENSA_SIGCONTEXT_H */