xil-crt0.s

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/* $Id: xil-crt0.S,v 1.1.4.2 2011/11/04 11:42:34 sadanan Exp $*/
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/**
* @file xil-crt0.S
*
* <pre>
* MODIFICATION HISTORY:
*
* Ver   Who  Date     Changes
* ----- ---- -------- ---------------------------------------------------
* 1.00a ecm  10/20/09 Initial version
* 3.05a sdm  02/02/12 Added code for profiling
* 3.06a sgd  05/16/12 Added global constructors and cleanup code
*                     Uart initialization based on compiler flag
* </pre>
*
* @note
*
* None.
*
******************************************************************************/

.extern XSmc_NorInit
.extern XSmc_SramInit

	.file	"xil-crt0.S"
	.section ".got2","aw"
	.align	2

	.text
.Lsbss_start:
	.long	__sbss_start

.Lsbss_end:
	.long	__sbss_end

.Lbss_start:
	.long	__bss_start

.Lbss_end:	
	.long	__bss_end

.Lstack:	
	.long	__stack

    
	.globl	_start
_start:
	bl      __cpu_init		/* Initialize the CPU first (BSP provides this) */

	mov	r0, #0
	
	/* clear sbss */
	ldr 	r1,.Lsbss_start		/* calculate beginning of the SBSS */
	ldr	r2,.Lsbss_end		/* calculate end of the SBSS */

.Lloop_sbss:
	cmp	r1,r2
	bge	.Lenclsbss		/* If no SBSS, no clearing required */
	str	r0, [r1], #4
	b	.Lloop_sbss

.Lenclsbss:  
	/* clear bss */
	ldr	r1,.Lbss_start		/* calculate beginning of the BSS */
	ldr	r2,.Lbss_end		/* calculate end of the BSS */

.Lloop_bss:	
	cmp	r1,r2
	bge	.Lenclbss		/* If no BSS, no clearing required */
	str	r0, [r1], #4
	b	.Lloop_bss

.Lenclbss:

	/* set stack pointer */
	ldr	r13,.Lstack		/* stack address */

#ifdef PEEP
	/* Initialize STDOUT */
	bl	Init_Uart
#endif

#ifdef PROFILING			/* defined in Makefile */
	/* Setup profiling stuff */
	bl	_profile_init
#endif /* PROFILING */


	/* Initialize the SMC interfaces for NOR and SRAM */
#ifndef USE_AMP
	bl	XSmc_NorInit

	bl	XSmc_SramInit
#endif

   /* run global constructors */ 
   bl __libc_init_array 

	/* make sure argc and argv are valid */
	mov	r0, #0
	mov	r1, #0

	/* Let her rip */
	bl	main

   /* Cleanup global constructors */ 
   bl __libc_fini_array 

#ifdef PROFILING
	/* Cleanup profiling stuff */
	bl	_profile_clean
#endif /* PROFILING */

        /* All done */
	bl	exit

.Lexit:	/* should never get here */
	b .Lexit

.Lstart:
	.size	_start,.Lstart-_start