source: rtems/bsps/powerpc/psim/start/start.S @ ff081aee

Last change on this file since ff081aee was ff081aee, checked in by Sebastian Huber <sebastian.huber@…>, on Nov 6, 2018 at 3:58:02 PM

score: Rename interrupt stack symbols

Rename

  • _Configuration_Interrupt_stack_area_begin in _ISR_Stack_area_begin,
  • _Configuration_Interrupt_stack_area_end in _ISR_Stack_area_end, and
  • _Configuration_Interrupt_stack_size in _ISR_Stack_size.

Move definitions to <rtems/score/isr.h>. The new names are considerable
shorter and in the right namespace.

Update #3459.

  • Property mode set to 100644
File size: 3.4 KB
Line 
1/*
2 * This is based on the mvme-crt0.S file from libgloss/rs6000.
3 * crt0.S -- startup file for PowerPC systems.
4 *
5 * Copyright (c) 1995 Cygnus Support
6 *
7 * The authors hereby grant permission to use, copy, modify, distribute,
8 * and license this software and its documentation for any purpose, provided
9 * that existing copyright notices are retained in all copies and that this
10 * notice is included verbatim in any distributions. No written agreement,
11 * license, or royalty fee is required for any of the authorized uses.
12 * Modifications to this software may be copyrighted by their authors
13 * and need not follow the licensing terms described here, provided that
14 * the new terms are clearly indicated on the first page of each file where
15 * they apply.
16 */
17
18#include <rtems/asm.h>
19#include <rtems/score/cpu.h>
20#include <libcpu/io.h>
21#include "ppc-asm.h"
22
23        .section ".got2","aw"
24        .align  2
25
26.LCTOC1 = .+32768
27
28        .extern FUNC_NAME(atexit)
29        .globl  FUNC_NAME(__atexit)
30        .section ".sdata","aw"
31        .align  2
32FUNC_NAME(__atexit):                    /* tell C's eabi-ctor's we have an atexit function */
33        .long   FUNC_NAME(atexit)@fixup /* and that it is to register __do_global_dtors */
34
35        .section ".fixup","aw"
36        .align  2
37        .long   FUNC_NAME(__atexit)
38
39        .section ".got2","aw"
40.Ltable = .-.LCTOC1
41        .long   .LCTOC1                 /* address we think .LCTOC1 is loaded at */
42
43.Lbss_start = .-.LCTOC1
44        .long   bsp_section_sbss_begin
45
46.Lend = .-.LCTOC1
47        .long   bsp_section_bss_end
48
49.Lstack = .-.LCTOC1                     /* stack address if set by user */
50        .long   _ISR_Stack_area_end
51
52        .text
53.Lptr:
54        .long .LCTOC1-.Laddr
55
56        .globl  __rtems_entry_point
57        .type   __rtems_entry_point,@function
58__rtems_entry_point:
59#if 1
60        .globl  _start
61        .type   _start,@function
62_start:
63#endif
64        bl      .Laddr                  /* get current address */
65.Laddr:
66        mflr    r4                      /* real address of .Laddr */
67        lwz     r5,(.Lptr-.Laddr)(r4)   /* linker generated address of .LCTOC1 */
68        add     r5,r5,r4                /* correct to real pointer */
69        lwz     r4,.Ltable(r5)          /* get linker's idea of where .Laddr is */
70        subf    r4,r4,r5                /* calculate difference between where linked and current */
71
72        /* clear bss */
73        lwz     r6,.Lbss_start(r5)      /* calculate beginning of the BSS */
74        lwz     r7,.Lend(r5)            /* calculate end of the BSS */
75        add     r6,r6,r4                /* adjust pointers */
76        add     r7,r7,r4
77
78        cmplw   1,r6,r7
79        bc      4,4,.Ldone
80
81        subf    r8,r6,r7                /* number of bytes to zero */
82        srwi    r9,r8,2                 /* number of words to zero */
83        mtctr   r9
84        li      r0,0                    /* zero to clear memory */
85        addi    r6,r6,-4                /* adjust so we can use stwu */
86.Lloop:
87        stwu    r0,4(r6)                /* zero bss */
88        bdnz    .Lloop
89
90.Ldone:
91
92        lwz     r0,.Lstack(r5)  /* stack area or 0 */
93        cmplwi  1,r0,0                  /* equal to 0? */
94        bc      12,6,.Lnostack          /* use default stack if == 0 */
95        mr      sp,r0                   /* use user defined stack */
96
97.Lnostack:
98#ifdef __ALTIVEC__
99        /* enable altivec; this requires the ALTIVEC user
100         * extension to be installed in the user extension
101         * slot 0!
102         */
103        mfmsr r0
104        oris  r0, r0, (1<<(31-16-6))
105        mtmsr r0
106        isync
107        /*
108         * set vscr and vrsave to known values
109         */
110        li    r0, 0
111        mtvrsave r0
112        vxor   0,0,0
113        mtvscr 0
114#endif
115        /* set up initial stack frame */
116        addi    sp,sp,-4                /* make sure we don't overwrite debug mem */
117        /* align */
118        li  r3, CPU_STACK_ALIGNMENT-1
119        andc    sp, sp, r3
120        lis     r0,0
121        stw     r0,0(sp)                /* clear back chain */
122        stwu    sp,-CPU_STACK_ALIGNMENT(sp)             /* push another stack frame */
123        bl  FUNC_NAME(__eabi)
124
125        /* Let her rip */
126        li      r3, 0                   /* command line */
127        bl      FUNC_NAME(boot_card)
128
129       .globl  FUNC_NAME(bsp_reset)
130FUNC_NAME(bsp_reset):
131        li  10,99                       /* 0x63 */
132        sc
133
134.Lstart:
135        .size   _start,.Lstart-_start
Note: See TracBrowser for help on using the repository browser.