Chris Zankel writes:

The following patches add support for the Xtensa processor architecture
to uClibc. They are based on a recent SVN checkout (12/05/2007).

The first patch (attached to this post) adds Xtensa support to various
shared configuration and make files. The following patches then include
the Xtensa specific files and directories.

I welcome any feedback and would appreciate it if you could include the
patches into the mainline tree. I am certainly committed to maintain the port. 

Bob Wilson was kind enough to review the patches.

Some notes about the architecture: Xtensa is a configurable and
extensible processor architecture developed by Tensilica. For more
information, please visit: www.linux-xtensa.org.

1 files changed, 33 insertions, 0 deletions

diff --git a/libc/sysdeps/linux/xtensa/bits/sigcontextinfo.h b/libc/sysdeps/linux/xtensa/bits/sigcontextinfo.h
new file mode 100644
index 000000000..8f3301c9a
--- /dev/null
+++ b/libc/sysdeps/linux/xtensa/bits/sigcontextinfo.h
@@ -0,0 +1,33 @@
+/* Copyright (C) 2003, 2007 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C 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.
+
+   The GNU C 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 the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
+   Boston, MA 02110-1301, USA.  */
+
+/* Also see register-dump.h, where we spill live registers to the
+   stack so that we can trace the stack backward.  */
+
+#define SIGCONTEXT unsigned long _info, ucontext_t *
+#define SIGCONTEXT_EXTRA_ARGS _info,
+
+/* ANDing with 0x3fffffff clears the window-size bits.
+   Assumes TASK_SIZE = 0x40000000.  */
+
+#define GET_PC(ctx)	((void *) (ctx->uc_mcontext.sc_pc & 0x3fffffff))
+#define GET_FRAME(ctx)	((void *) ctx->uc_mcontext.sc_a[1])
+#define GET_STACK(ctx)	((void *) ctx->uc_mcontext.sc_a[1])
+#define CALL_SIGHANDLER(handler, signo, ctx) \
+  (handler)((signo), SIGCONTEXT_EXTRA_ARGS (ctx))
+