Diffstat (limited to 'include/asm-powerpc/sstep.h')
1 files changed, 26 insertions, 0 deletions
diff --git a/include/asm-powerpc/sstep.h b/include/asm-powerpc/sstep.h
new file mode 100644
@@ -0,0 +1,26 @@
+ * Copyright (C) 2004 Paul Mackerras <firstname.lastname@example.org>, IBM
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ * We don't allow single-stepping an mtmsrd that would clear
+ * MSR_RI, since that would make the exception unrecoverable.
+ * Since we need to single-step to proceed from a breakpoint,
+ * we don't allow putting a breakpoint on an mtmsrd instruction.
+ * Similarly we don't allow breakpoints on rfid instructions.
+ * These macros tell us if an instruction is a mtmsrd or rfid.
+ * Note that IS_MTMSRD returns true for both an mtmsr (32-bit)
+ * and an mtmsrd (64-bit).
+#define IS_MTMSRD(instr) (((instr) & 0xfc0007be) == 0x7c000124)
+#define IS_RFID(instr) (((instr) & 0xfc0007fe) == 0x4c000024)
+/* Emulate instructions that cause a transfer of control. */
+extern int emulate_step(struct pt_regs *regs, unsigned int instr);