nds32: standalone support

Add standalone program related support for nds32 architecture.

Signed-off-by: Macpaul Lin <macpaul@andestech.com>

examples/standalone/nds32.lds

+/*
+ * Copyright (C) 2011 Andes Technology Corporation
+ * Shawn Lin, Andes Technology Corporation <nobuhiro@andestech.com>
+ * Macpaul Lin, Andes Technology Corporation <macpaul@andestech.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+OUTPUT_FORMAT("elf32-nds32", "elf32-nds32", "elf32-nds32")
+OUTPUT_ARCH(nds32)
+ENTRY(_start)
+SECTIONS
+{
+	. = ALIGN(4);
+	.text :
+	{
+		*(.text)
+	}
+
+	. = ALIGN(4);
+	.data : { *(.data) }
+
+	. = ALIGN(4);
+
+	.got : {
+		__got_start = .;
+		*(.got)
+		__got_end = .;
+	}
+
+	. = ALIGN(4);
+	__bss_start = .;
+	.bss : { *(.bss) }
+	__bss_end = .;
+
+	. = ALIGN(4);
+	.rela.text : { *(.rela.text .rela.text.* .rela.gnu.linkonce.t.*) }
+
+	_end = .;
+}

examples/standalone/stubs.c

@@ -167,8 +167,23 @@ gd_t *global_data;
 "	jmp %%g1\n"					\
 "	nop\n"						\
 	: : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "g1" );
-
+#elif defined(CONFIG_NDS32)
+/*
+ * r16 holds the pointer to the global_data. gp is call clobbered.
+ * not support reduced register (16 GPR).
+ */
+#define EXPORT_FUNC(x) \
+	asm volatile (			\
+"	.globl " #x "\n"		\
+#x ":\n"				\
+"	lwi	$r16, [$gp + (%0)]\n"	\
+"	lwi	$r16, [$r16 + (%1)]\n"	\
+"	jr	$r16\n"			\
+	: : "i"(offsetof(gd_t, jt)), "i"(XF_ ## x * sizeof(void *)) : "$r16");
 #else
+/*"	addi	$sp, $sp, -24\n"	\
+"	br	$r16\n"			\*/
+
 #error stubs definition missing for this architecture
 #endif
 

examples/standalone/x86-testapp.c

@@ -52,6 +52,17 @@ asm volatile (						\
 "	lw	$25, %1($25)\n"				\
 "	jr	$25\n"					\
 	: : "i"(offsetof(xxx_t, pfunc)), "i"(XF_ ## x * sizeof(void *)) : "t9");
+#elif defined(__nds32__)
+#define EXPORT_FUNC(x)					\
+asm volatile (						\
+"	.globl mon_" #x "\n"				\
+"mon_" #x ":\n"						\
+"	lwi	$r16, [$gp + (%0)]\n"			\
+"	lwi	$r16, [$r16 + (%1)]\n"			\
+"	jr	$r16\n"					\
+: : "i"(offsetof(xxx_t, pfunc)),			\
+"i"(XF_ ## x * sizeof(void *)) : "$r16");
+
 #else
 #error [No stub code for this arch]
 #endif
@@ -72,6 +83,8 @@ int main(void)
 	register volatile xxx_t *pq asm("r8");
 #elif defined(__mips__)
 	register volatile xxx_t *pq asm("k0");
+#elif defined(__nds32__)
+	register volatile xxx_t *pq asm("$r16");
 #endif
 	char buf[32];