sysalib.s

菲利普22系列 vxworks bsp 可以用来可以和其他版本的ARM vxworks bsp（特别是7内核的进行比较）进行比较可以加深对BSP的理解和掌握

/* Copyright 1984-2001 Wind River Systems, Inc. */

#define _ASMLANGUAGE
#include "vxWorks.h"
#include "arch/arm/arm.h"
#include "regs.h"
#include "sysLib.h"
#include "config.h"
#include "wrSbcArm7.h"

    .data
    .globl  FUNC(copyright_wind_river)
    .long   FUNC(copyright_wind_river)
/* internals */

    .globl    FUNC(sysInit)        /* start of system code */
    .globl    FUNC(lpc2210ExcVecInit)        /* lpc2210ExcVecInit, this is to replace vxworks's excVecInit */
    .globl    FUNC(sysIntStackSplit)    /* routine to split interrupt stack */

/* externals */

    .extern    FUNC(usrInit)        /* system initialization routine */

    .extern    FUNC(vxSvcIntStackBase)    /* base of SVC-mode interrupt stack */
    .extern    FUNC(vxSvcIntStackEnd)    /* end of SVC-mode interrupt stack */
    .extern    FUNC(vxIrqIntStackBase)    /* base of IRQ-mode interrupt stack */
    .extern    FUNC(vxIrqIntStackEnd)    /* end of IRQ-mode interrupt stack */

    .extern FUNC(armInitExceptionModes)
    .extern FUNC(_func_armIrqHandler)
    .extern FUNC(excIntHandle)

    .text
    .balign 4

_ARM_FUNCTION(lpc2210ExcVecInit)
    stmfd sp!, {r0-r10,lr}
    bl FUNC(armInitExceptionModes)

    ldr r0, L$__func_armIrqHandler
    ldr r1, L$_excIntHandle
    str r1, [r0]

    nop
    ldmfd sp!, {r0-r10,pc}
    
L$_excIntHandle:
    .long excIntHandle
L$__func_armIrqHandler:
    .long _func_armIrqHandler
    
/*******************************************************************************
*
* sysIntStackSplit - split interrupt stack and set interrupt stack pointers
*
* This routine is called, via a function pointer, during kernel
* initialisation.  It splits the allocated interrupt stack into IRQ and
* SVC-mode stacks and sets the processor's IRQ stack pointer. Note that
* the pointer passed points to the bottom of the stack allocated i.e.
* highest address+1.
*
* IRQ stack needs 6 words per nested interrupt;
* SVC-mode will need a good deal more for the C interrupt handlers.
* For now, use ratio 1:7 with any excess allocated to the SVC-mode stack
* at the lowest address.
*
* Note that FIQ is not handled by VxWorks so no stack is allocated for it.
*
* The stacks and the variables that describe them look like this.
* .CS
*
*         - HIGH MEMORY -
*     ------------------------ <--- vxIrqIntStackBase (r0 on entry)
*     |                      |
*     |       IRQ-mode       |
*     |    interrupt stack   |
*     |                      |
*     ------------------------ <--{ vxIrqIntStackEnd
*     |                      |    { vxSvcIntStackBase
*     |       SVC-mode       |
*     |    interrupt stack   |
*     |                      |
*     ------------------------ <--- vxSvcIntStackEnd
*         - LOW  MEMORY -
* .CE
*
* NOTE: This routine should not be called by the user.

* void sysIntStackSplit
*     (
*     char *pBotStack   /@ pointer to bottom of interrupt stack @/
*     long size        /@ size of stack @/
*     )

*/


_ARM_FUNCTION_CALLED_FROM_C(sysIntStackSplit)

    /*
     * r0 = base of space allocated for stacks (i.e. highest address)
     * r1 = size of space
     */

    SUB    r2, r0, r1            /* r2->lowest usable address */
    LDR    r3, L$_vxSvcIntStackEnd
    STR    r2, [r3]            /*  == end of SVC-mode stack */
    SUB    r2, r0, r1, ASR #3        /* leave 1/8 for IRQ */
    LDR    r3, L$_vxSvcIntStackBase
    STR    r2, [r3]

    /* now allocate IRQ stack, setting irq_sp */

    LDR    r3, L$_vxIrqIntStackEnd
    STR    r2, [r3]
    LDR    r3, L$_vxIrqIntStackBase
    STR    r0, [r3]

    MRS    r2, cpsr
    BIC    r3, r2, #MASK_MODE
    ORR    r3, r3, #MODE_IRQ32 | I_BIT    /* set irq_sp */
    MSR    cpsr, r3
    MOV    sp, r0

    /* switch back to original mode and return */

    MSR    cpsr, r2

#if    (CPU == ARMARCH4_T)
    BX     lr
#else
    MOV    pc, lr
#endif    /* (CPU == ARMARCH4_T) */

#ifdef INCLUDE_VWARE_LAUNCH
#include "sysAVware.s"
#endif /* INCLUDE_VWARE_LAUNCH */

/******************************************************************************/

/*
 * PC-relative-addressable pointers - LDR Rn,=sym is broken
 * note "_" after "$" to stop preprocessor preforming substitution
 */

    .balign    4

L$_vxSvcIntStackBase:
    .long    FUNC(vxSvcIntStackBase)

L$_vxSvcIntStackEnd:
    .long    FUNC(vxSvcIntStackEnd)

L$_vxIrqIntStackBase:
    .long    FUNC(vxIrqIntStackBase)

L$_vxIrqIntStackEnd:
    .long    FUNC(vxIrqIntStackEnd)