121 lines
3.6 KiB
ArmAsm
121 lines
3.6 KiB
ArmAsm
/*
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* This file is part of the COMROGUE Operating System for Raspberry Pi
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*
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* Copyright (c) 2013, Eric J. Bowersox / Erbosoft Enterprises
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* All rights reserved.
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*
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* This program is free for commercial and non-commercial use as long as the following conditions are
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* adhered to.
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*
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* Copyright in this file remains Eric J. Bowersox and/or Erbosoft, and as such any copyright notices
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* in the code are not to be removed.
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*
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* Redistribution and use in source and binary forms, with or without modification, are permitted
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* provided that the following conditions are met:
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*
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* * Redistributions of source code must retain the above copyright notice, this list of conditions and
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* the following disclaimer.
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* * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and
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* the following disclaimer in the documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
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* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
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* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
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* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
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* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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* "Raspberry Pi" is a trademark of the Raspberry Pi Foundation.
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*/
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#include <comrogue/internals/layout.h>
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#include <comrogue/internals/sctlr.h>
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.section ".first.init.text"
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.globl COMROGUEStart
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/* entry: r0 = physical (low-memory) address of STARTUP_INFO1 structure */
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COMROGUEStart:
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/* initialize the stack pointer */
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ldr sp, =.initstack
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/* clear init bss */
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ldr r4, =vmaInitBss
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ldr r5, =vmaFirstFree
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mov r6, #0
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mov r7, #0
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mov r8, #0
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mov r9, #0
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bl .erase
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/* clear resident bss */
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ldr r4, =vmaKernelBss
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ldr r5, =vmaInitCode
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bl .erase
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/* initialize trace */
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push {r0}
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bl TrInit
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#if 0
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ldr r0, =.msg0
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bl TrWriteString8
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#endif
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pop {r0}
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/* copy startup info to our local buffer */
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mov r1, r0
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ldr r0, =kiStartupInfo
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ldr r2, [r1] /* get number of bytes to copy */
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ldr ip, =StrCopyMem /* this is needed to branch to a library function */
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ldr lr, =.postCopy
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mov pc, ip
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.postCopy:
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#if 0
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ldr r0, =.msg1
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bl TrWriteString8
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#endif
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mcr p15, 0, r6, c7, c7, 0 /* clear caches */
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mcr p15, 0, r6, c8, c7, 0 /* clear TLB */
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mrc p15, 0, r0, c1, c0, 0
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orr r0, r0, # SCTLR_I /* activate instruction cache */
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orr r0, r0, # SCTLR_C /* activate data cache */
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mcr p15, 0, r0, c1, c0, 0
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/* transfer to C code to continue initialization */
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ldr ip, =KiSystemStartup
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ldr lr, =.hang
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mov pc, ip /* transfer to C code */
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.hang:
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wfe /* if KiSystemStartup returns, just hang */
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b .hang
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/* Simple erase routine. Start and end addresses in r4 and r5. r6-r9 assumed to be 0. */
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/* Do not touch r0-r2. */
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.erase:
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cmp r4, r5 /* are we done? */
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movhs pc, lr /* yes, return */
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stm r4!, {r6-r9} /* stomp 16 bytes */
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b .erase
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#if 0
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.balign 4
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.msg0:
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.asciz "got here 2\n"
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.balign 4
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.msg1:
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.asciz "got here 3\n"
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#endif
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.section ".init.bss"
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.balign 8
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.globl g_pInitHeapBlock
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g_pInitHeapBlock:
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.space SIZE_INIT_HEAP
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.balign 4
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.space SIZE_INIT_STACK
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.initstack:
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