diff options
Diffstat (limited to 'c/src/lib/libbsp/powerpc/ep1a/start/start.S')
-rw-r--r-- | c/src/lib/libbsp/powerpc/ep1a/start/start.S | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/powerpc/ep1a/start/start.S b/c/src/lib/libbsp/powerpc/ep1a/start/start.S new file mode 100644 index 0000000000..873d729787 --- /dev/null +++ b/c/src/lib/libbsp/powerpc/ep1a/start/start.S @@ -0,0 +1,151 @@ +/* + * This is based on the mvme-crt0.S file from libgloss/rs6000. + * crt0.S -- startup file for PowerPC systems. + * + * (c) 1998, Radstone Technology plc. + * + * + * This is an unpublished work the copyright in which vests + * in Radstone Technology plc. All rights reserved. + * + * The information contained herein is the property of Radstone + * Technology plc. and is supplied without liability for + * errors or omissions and no part may be reproduced, used or + * disclosed except as authorized by contract or other written + * permission. The copyright and the foregoing + * restriction on reproduction, use and disclosure extend to + * all the media in which this information may be + * embodied. + * + * Copyright (c) 1995 Cygnus Support + * + * The authors hereby grant permission to use, copy, modify, distribute, + * and license this software and its documentation for any purpose, provided + * that existing copyright notices are retained in all copies and that this + * notice is included verbatim in any distributions. No written agreement, + * license, or royalty fee is required for any of the authorized uses. + * Modifications to this software may be copyrighted by their authors + * and need not follow the licensing terms described here, provided that + * the new terms are clearly indicated on the first page of each file where + * they apply. + * + * start.S,v 1.4 2002/04/19 13:25:27 joel Exp + */ +/* +#include <ppc-asm.h> +#include <bsp.h> +*/ + +#include <asm.h> +#include <rtems/score/cpu.h> +#include <libcpu/io.h> +#include <ppc-asm.h> + +#define H0_60X_ICE 0x8000 /* HID0 I-Cache Enable */ +#define H0_60X_DCE 0x4000 /* HID0 D-Cache Enable */ + + .file "start.s" + + .extern FUNC_NAME(atexit) + .globl FUNC_NAME(__atexit) + .section ".sdata","aw" + .align 2 +FUNC_NAME(__atexit): /* tell C's eabi-ctor's we have an atexit function */ + .long FUNC_NAME(atexit)@fixup /* and that it is to register __do_global_dtors */ + + .section ".fixup","aw" + .align 2 + .long FUNC_NAME(__atexit) + + .text + .globl __rtems_entry_point + .type __rtems_entry_point,@function +__rtems_entry_point: + + /* Set MSR */ + /* + * Enable data and instruction address translation and floating point + */ + li r3,MSR_IR | MSR_DR | MSR_FP + mtmsr r3 + + /* XXX - ADD BACK IN CACHING INSTRUCTIONS */ + + /* clear bss */ + lis r6,__bss_start@h + ori r6,r6,__bss_start@l + lis r7,__bss_end@h + ori r7,r7,__bss_end@l + + cmplw 1,r6,r7 + bc 4,4,.Lbss_done + + subf r8,r6,r7 /* number of bytes to zero */ + srwi r9,r8,2 /* number of words to zero */ + mtctr r9 + li r0,0 /* zero to clear memory */ + addi r6,r6,-4 /* adjust so we can use stwu */ +.Lbss_loop: + stwu r0,4(r6) /* zero bss */ + bdnz .Lbss_loop + +.Lbss_done: + + /* clear sbss */ + lis r6,__sbss_start@h + ori r6,r6,__sbss_start@l + lis r7,__sbss_end@h + ori r7,r7,__sbss_end@l + + cmplw 1,r6,r7 + bc 4,4,.Lsbss_done + + subf r8,r6,r7 /* number of bytes to zero */ + srwi r9,r8,2 /* number of words to zero */ + mtctr r9 + li r0,0 /* zero to clear memory */ + addi r6,r6,-4 /* adjust so we can use stwu */ +.Lsbss_loop: + stwu r0,4(r6) /* zero sbss */ + bdnz .Lsbss_loop + +.Lsbss_done: + + lis sp,__stack@h + ori sp,sp,__stack@l + + /* set up initial stack frame */ + addi sp,sp,-4 /* make sure we don't overwrite debug mem */ + lis r0,0 + stw r0,0(sp) /* clear back chain */ + stwu sp,-56(sp) /* push another stack frame */ + + lis r5,environ@ha + la r5,environ@l(r5) /* environp */ + li r4, 0 /* argv */ + li r3, 0 /* argc */ + + /* Let her rip */ + bl FUNC_NAME(boot_card) + + /* + * This should never get reached + */ + /* + * Return MSR to its reset state + */ + li r3,0 + mtmsr r3 + isync + + /* + * Call reset entry point + */ + lis r3,0xfff0 + ori r3,r3,0x100 + mtlr r3 + blr +.Lstart: + .size _start,.Lstart-_start + + .comm environ,4,4 |