nios2: Add architecture emulation support

Add support for emulating Altera NiosII R1 architecture into qemu.
This patch is based on previous work by Chris Wulff from 2012 and
updated to latest mainline QEMU.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Chris Wulff <crwulff@gmail.com>
Cc: Jeff Da Silva <jdasilva@altera.com>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Sandra Loosemore <sandra@codesourcery.com>
Cc: Yves Vandervennet <yvanderv@altera.com>
Cc: Alexander Graf <agraf@suse.de>
Message-Id: <20170118220146.489-3-marex@denx.de>
[rth: Remove tlb_flush from nios2_cpu_reset.]
Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 47 insertions, 0 deletions

diff --git a/target/nios2/op_helper.c b/target/nios2/op_helper.c
new file mode 100644
index 0000000000..538853cda7
--- /dev/null
+++ b/target/nios2/op_helper.c
@@ -0,0 +1,47 @@
+/*
+ * Altera Nios II helper routines.
+ *
+ * Copyright (C) 2012 Chris Wulff <crwulff@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+#include "cpu.h"
+#include "exec/helper-proto.h"
+#include "exec/cpu_ldst.h"
+
+#if !defined(CONFIG_USER_ONLY)
+void helper_mmu_read_debug(CPUNios2State *env, uint32_t rn)
+{
+    mmu_read_debug(env, rn);
+}
+
+void helper_mmu_write(CPUNios2State *env, uint32_t rn, uint32_t v)
+{
+    mmu_write(env, rn, v);
+}
+
+void helper_check_interrupts(CPUNios2State *env)
+{
+    nios2_check_interrupts(env);
+}
+#endif /* !CONFIG_USER_ONLY */
+
+void helper_raise_exception(CPUNios2State *env, uint32_t index)
+{
+    CPUState *cs = ENV_GET_CPU(env);
+    cs->exception_index = index;
+    cpu_loop_exit(cs);
+}