nds32: add support for new architecture

Add support for Andes Technology NDS32 architecture.
See here http://www.andestech.com/en/index/index.htm for more
informaton. Verification of the port from an older uClibc
port was done on a sponsored AG101p board.

The testsuite only has 5 errors, three are related to
an existing bug in dlclose() with LT.old, also happening
on cris32 and m68k.

Failures to fallocate/posix_fallocate are unresolved.

Thanks to Andes Technology sponsoring the hardware and
being very helpful while doing the uClibc-ng porting.

Signed-off-by: Waldemar Brodkorb <wbx@uclibc-ng.org>

1 files changed, 125 insertions, 0 deletions

diff --git a/libc/sysdeps/linux/nds32/sysdep.S b/libc/sysdeps/linux/nds32/sysdep.S
new file mode 100644
index 000000000..4e86a26e0
--- /dev/null
+++ b/libc/sysdeps/linux/nds32/sysdep.S
@@ -0,0 +1,125 @@
+/*
+ * Copyright (C) 2016 Andes Technology, Inc.
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ */
+
+/* Copyright (C) 1991-2003 Free Software Foundation, Inc.
+
+   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., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+ 
+#include <sysdep.h>
+#define _ERRNO_H
+#include <bits/errno.h>
+
+.text
+
+.globl C_SYMBOL_NAME(errno)
+.globl __syscall_error
+
+ENTRY (__syscall_error)
+#ifdef OLD_ABI
+	subri $r5, $r5, #0
+#else
+	subri $r0, $r0, #0
+#endif
+
+#define __syscall_error __syscall_error_1
+
+#undef syscall_error
+#ifdef NO_UNDERSCORES
+__syscall_error:
+#else
+syscall_error:
+#endif
+
+#ifdef PIC
+	/* set GP register */
+	pushm	$gp, $lp
+#ifdef __NDS32_N1213_43U1H__
+	jal	2f
+	sethi	$gp,	hi20(_GLOBAL_OFFSET_TABLE_)
+	ori	$gp,	$gp,	lo12(_GLOBAL_OFFSET_TABLE_+4)
+	add	$gp,	$gp,	$lp
+#else
+	mfusr	$r15, $PC
+	sethi	$gp,	hi20(_GLOBAL_OFFSET_TABLE_+4)
+	ori	$gp,	$gp,	lo12(_GLOBAL_OFFSET_TABLE_+8)
+	add	$gp,	$gp,	$r15
+#endif
+#endif
+
+#if defined (EWOULDBLOCK_sys) && EWOULDBLOCK_sys != EAGAIN
+	/* We translate the system's EWOULDBLOCK error into EAGAIN.
+	   The GNU C library always defines EWOULDBLOCK==EAGAIN.
+	   EWOULDBLOCK_sys is the original number.  */
+	   push	$t0
+	   li	$t0, EWOULDBLOCK_sys
+	   bne	$r0, $t0, 1f
+	   pop	$t0
+	   li	$r0, EAGAIN
+1:
+#endif
+
+#ifdef _LIBC_REENTRANT
+	push	$lp
+	push	$r0
+#if defined(NDS32_ABI_2) || defined(NDS32_ABI_2FP)
+#else
+	addi	$sp,	$sp, -24
+#endif
+
+#ifdef PIC
+	bal	C_SYMBOL_NAME(__errno_location@PLT)
+#else
+	bal	C_SYMBOL_NAME(__errno_location)
+#endif
+#if defined(NDS32_ABI_2) || defined(NDS32_ABI_2FP)
+#else
+	addi	$sp,	$sp, 24
+#endif
+	pop	$r1
+
+	swi	$r1, [$r0]
+	li	$r0, -1
+	pop	$lp
+#ifdef PIC
+	/* restore GP register */
+	popm	$gp, $lp
+#endif
+2:
+	ret
+#else
+#ifndef	PIC
+	l.w	$r1, .L1
+	swi	$r0, [$r1]
+	li	$r0, -1
+	ret
+
+.L1:	.long C_SYMBOL_NAME(errno)
+#else
+	s.w	$r0, errno@GOTOFF
+	li	$r0, -1
+	
+	/* restore GP register */
+	popm	$gp, $lp
+2:
+	ret
+
+#endif
+#endif
+
+#undef __syscall_error
+END (__syscall_error)