sh: kdump support.

This adds support for kexec based crash dumps.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/include/asm-sh/kexec.h b/include/asm-sh/kexec.h
index 9d235af..da36a75 100644
--- a/include/asm-sh/kexec.h
+++ b/include/asm-sh/kexec.h
@@ -1,5 +1,8 @@
-#ifndef _SH_KEXEC_H
-#define _SH_KEXEC_H
+#ifndef __ASM_SH_KEXEC_H
+#define __ASM_SH_KEXEC_H
+
+#include <asm/ptrace.h>
+#include <asm/string.h>
 
 /*
  * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
@@ -25,8 +28,37 @@
 
 #define MAX_NOTE_BYTES 1024
 
-/* Provide a dummy definition to avoid build failures. */
 static inline void crash_setup_regs(struct pt_regs *newregs,
-					struct pt_regs *oldregs) { }
+				    struct pt_regs *oldregs)
+{
+	if (oldregs)
+		memcpy(newregs, oldregs, sizeof(*newregs));
+	else {
+		__asm__ __volatile__ ("mov r0, %0" : "=r" (newregs->regs[0]));
+		__asm__ __volatile__ ("mov r1, %0" : "=r" (newregs->regs[1]));
+		__asm__ __volatile__ ("mov r2, %0" : "=r" (newregs->regs[2]));
+		__asm__ __volatile__ ("mov r3, %0" : "=r" (newregs->regs[3]));
+		__asm__ __volatile__ ("mov r4, %0" : "=r" (newregs->regs[4]));
+		__asm__ __volatile__ ("mov r5, %0" : "=r" (newregs->regs[5]));
+		__asm__ __volatile__ ("mov r6, %0" : "=r" (newregs->regs[6]));
+		__asm__ __volatile__ ("mov r7, %0" : "=r" (newregs->regs[7]));
+		__asm__ __volatile__ ("mov r8, %0" : "=r" (newregs->regs[8]));
+		__asm__ __volatile__ ("mov r9, %0" : "=r" (newregs->regs[9]));
+		__asm__ __volatile__ ("mov r10, %0" : "=r" (newregs->regs[10]));
+		__asm__ __volatile__ ("mov r11, %0" : "=r" (newregs->regs[11]));
+		__asm__ __volatile__ ("mov r12, %0" : "=r" (newregs->regs[12]));
+		__asm__ __volatile__ ("mov r13, %0" : "=r" (newregs->regs[13]));
+		__asm__ __volatile__ ("mov r14, %0" : "=r" (newregs->regs[14]));
+		__asm__ __volatile__ ("mov r15, %0" : "=r" (newregs->regs[15]));
 
-#endif /* _SH_KEXEC_H */
+		__asm__ __volatile__ ("sts pr, %0" : "=r" (newregs->pr));
+		__asm__ __volatile__ ("sts macl, %0" : "=r" (newregs->macl));
+		__asm__ __volatile__ ("sts mach, %0" : "=r" (newregs->mach));
+
+		__asm__ __volatile__ ("stc gbr, %0" : "=r" (newregs->gbr));
+		__asm__ __volatile__ ("stc sr, %0" : "=r" (newregs->sr));
+
+		newregs->pc = (unsigned long)current_text_addr();
+	}
+}
+#endif /* __ASM_SH_KEXEC_H */