nios2: Add usermode binaries emulation

Add missing bits for qemu-user required for emulating Altera Nios2
userspace binaries.

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>
Reviewed-by: Alexander Graf <agraf@suse.de>
Message-Id: <20170118220146.489-4-marex@denx.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 26 insertions, 0 deletions

diff --git a/linux-user/nios2/target_signal.h b/linux-user/nios2/target_signal.h
new file mode 100644
index 0000000000..23a8267696
--- /dev/null
+++ b/linux-user/nios2/target_signal.h
@@ -0,0 +1,26 @@
+#ifndef TARGET_SIGNAL_H
+#define TARGET_SIGNAL_H
+
+#include "cpu.h"
+
+/* this struct defines a stack used during syscall handling */
+
+typedef struct target_sigaltstack {
+    abi_long ss_sp;
+    abi_ulong ss_size;
+    abi_long ss_flags;
+} target_stack_t;
+
+/* sigaltstack controls  */
+#define TARGET_SS_ONSTACK     1
+#define TARGET_SS_DISABLE     2
+
+#define TARGET_MINSIGSTKSZ    2048
+#define TARGET_SIGSTKSZ       8192
+
+static inline abi_ulong get_sp_from_cpustate(CPUNios2State *state)
+{
+    return state->regs[R_SP];
+}
+
+#endif /* TARGET_SIGNAL_H */