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-rw-r--r--arch/xtensa/include/asm/traps.h118
1 files changed, 118 insertions, 0 deletions
diff --git a/arch/xtensa/include/asm/traps.h b/arch/xtensa/include/asm/traps.h
new file mode 100644
index 000000000..f720a57d0
--- /dev/null
+++ b/arch/xtensa/include/asm/traps.h
@@ -0,0 +1,118 @@
+/*
+ * arch/xtensa/include/asm/traps.h
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2012 Tensilica Inc.
+ */
+#ifndef _XTENSA_TRAPS_H
+#define _XTENSA_TRAPS_H
+
+#include <asm/ptrace.h>
+
+/*
+ * Per-CPU exception handling data structure.
+ * EXCSAVE1 points to it.
+ */
+struct exc_table {
+ /* Kernel Stack */
+ void *kstk;
+ /* Double exception save area for a0 */
+ unsigned long double_save;
+ /* Fixup handler */
+ void *fixup;
+ /* For passing a parameter to fixup */
+ void *fixup_param;
+ /* Fast user exception handlers */
+ void *fast_user_handler[EXCCAUSE_N];
+ /* Fast kernel exception handlers */
+ void *fast_kernel_handler[EXCCAUSE_N];
+ /* Default C-Handlers */
+ void *default_handler[EXCCAUSE_N];
+};
+
+/*
+ * handler must be either of the following:
+ * void (*)(struct pt_regs *regs);
+ * void (*)(struct pt_regs *regs, unsigned long exccause);
+ */
+extern void * __init trap_set_handler(int cause, void *handler);
+extern void do_unhandled(struct pt_regs *regs, unsigned long exccause);
+void fast_second_level_miss(void);
+
+/* Initialize minimal exc_table structure sufficient for basic paging */
+static inline void __init early_trap_init(void)
+{
+ static struct exc_table exc_table __initdata = {
+ .fast_kernel_handler[EXCCAUSE_DTLB_MISS] =
+ fast_second_level_miss,
+ };
+ __asm__ __volatile__("wsr %0, excsave1\n" : : "a" (&exc_table));
+}
+
+void secondary_trap_init(void);
+
+static inline void spill_registers(void)
+{
+#if XCHAL_NUM_AREGS > 16
+ __asm__ __volatile__ (
+ " call8 1f\n"
+ " _j 2f\n"
+ " retw\n"
+ " .align 4\n"
+ "1:\n"
+#if XCHAL_NUM_AREGS == 32
+ " _entry a1, 32\n"
+ " addi a8, a0, 3\n"
+ " _entry a1, 16\n"
+ " mov a12, a12\n"
+ " retw\n"
+#else
+ " _entry a1, 48\n"
+ " call12 1f\n"
+ " retw\n"
+ " .align 4\n"
+ "1:\n"
+ " .rept (" __stringify(XCHAL_NUM_AREGS) " - 16) / 12\n"
+ " _entry a1, 48\n"
+ " mov a12, a0\n"
+ " .endr\n"
+ " _entry a1, 16\n"
+#if XCHAL_NUM_AREGS % 12 == 0
+ " mov a12, a12\n"
+#elif XCHAL_NUM_AREGS % 12 == 4
+ " mov a4, a4\n"
+#elif XCHAL_NUM_AREGS % 12 == 8
+ " mov a8, a8\n"
+#endif
+ " retw\n"
+#endif
+ "2:\n"
+ : : : "a8", "a9", "memory");
+#else
+ __asm__ __volatile__ (
+ " mov a12, a12\n"
+ : : : "memory");
+#endif
+}
+
+struct debug_table {
+ /* Pointer to debug exception handler */
+ void (*debug_exception)(void);
+ /* Temporary register save area */
+ unsigned long debug_save[1];
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+ /* Save area for DBREAKC registers */
+ unsigned long dbreakc_save[XCHAL_NUM_DBREAK];
+ /* Saved ICOUNT register */
+ unsigned long icount_save;
+ /* Saved ICOUNTLEVEL register */
+ unsigned long icount_level_save;
+#endif
+};
+
+void debug_exception(void);
+
+#endif /* _XTENSA_TRAPS_H */