CVS: blob/src/blob stack.S,NONE,1.1 rest-ld-script,1.1,1.2 trampoline.S,1.2,1.3

[Erik M. <er...@us...>]

Update of /cvsroot/blob/blob/src/blob
In directory usw-pr-cvs1:/tmp/cvs-serv30674

Modified Files:
	rest-ld-script trampoline.S 
Added Files:
	stack.S 
Log Message:
- Move the stack into the .bss section
- Actually clear the .bss section before we jump to C code


--- NEW FILE: stack.S ---
/*
 * stack.S: blob stack
 *
 * Copyright (C) 2001  Erik Mouw (J.A...@it...)
 *
 * $Id: stack.S,v 1.1 2001/10/28 20:34:41 erikm Exp $
 *
 * 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
 *
 */

.ident "$Id: stack.S,v 1.1 2001/10/28 20:34:41 erikm Exp $"

#ifdef HAVE_CONFIG_H
# include <blob/config.h>
#endif


.section ".stack"
	/* 8kB stack should be enough */
	.space	(8 * 1024)

Index: rest-ld-script
===================================================================
RCS file: /cvsroot/blob/blob/src/blob/rest-ld-script,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -d -r1.1 -r1.2
--- rest-ld-script	2001/10/07 19:04:25	1.1
+++ rest-ld-script	2001/10/28 20:34:41	1.2
@@ -53,12 +53,22 @@
 	. = ALIGN(4);
 	.ptaglist : {
 		__ptagtable_begin = .;
-			*(.ptaglist)
+		*(.ptaglist)
 		__ptagtable_end = .;
 	}
 
-	/* the BSS section should be the last section */
+	/* the BSS section should *always* be the last section */
 	. = ALIGN(4);
-	.bss : { *(.bss) }
+	.bss : {
+		__bss_start = .;
+		/* first the real BSS data */
+		*(.bss) 
+
+		/* and next the stack */
+		. = ALIGN(4);
+		*(.stack)
+		__stack_end = .;
+		__bss_end = .;
+	}
 }
 

Index: trampoline.S
===================================================================
RCS file: /cvsroot/blob/blob/src/blob/trampoline.S,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -d -r1.2 -r1.3
--- trampoline.S	2001/10/07 19:34:17	1.2
+++ trampoline.S	2001/10/28 20:34:41	1.3
@@ -24,11 +24,35 @@
 #ifdef HAVE_CONFIG_H
 # include <blob/config.h>
 #endif
-	
+
 .text
 
 .globl _trampoline
 _trampoline:
+	/* clear the BSS section */
+	ldr	r1, bss_start
+	ldr	r0, bss_end
+	sub	r0, r0, r1
+
+	/* r1 = start address */
+	/* r0 = #number of bytes */
+	mov	r2, #0
+
+clear_bss:
+	stmia	r1!, {r2}
+	subs	r0, r0, #4
+	bne	clear_bss
+
+	/* setup the stack pointer */
+	ldr	r0, stack_end
+	sub	sp, r0, #4
+
+	/* jump to C code */
 	bl	main
 	/* if main ever returns we just call it again */
 	b	_trampoline
+
+
+bss_start:	.word	__bss_start
+bss_end:	.word	__bss_end
+stack_end:	.word	__stack_end