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/******************************************************************************
* Copyright (c) 2004, 2008 IBM Corporation
* All rights reserved.
* This program and the accompanying materials
* are made available under the terms of the BSD License
* which accompanies this distribution, and is available at
* http://www.opensource.org/licenses/bsd-license.php
*
* Contributors:
* IBM Corporation - initial implementation
*****************************************************************************/
#define STACKSIZE 0x100000
#include <macros.h>
.section ".toc","aw" # TOC entries are needed for relocation
.exception_stack_frame_toc:
.tc exception_stack_frame[TC],exception_stack_frame
.exit_sp_toc:
.tc _exit_sp[TC],_exit_sp
.prom_entry_toc:
.tc _prom_entry[TC],_prom_entry
.previous
/*
Function:
Input:
r3:
r4:
r5: prom entry
Output:
Decription: Main entry point, called from OF
*/
C_ENTRY(_entry)
mr r3, r6 # parm 0 passed in r6
mr r4, r7 # parm 1 passed in r7
mr r6, r1 # save stack pointer
mflr r7 # save link register
bcl 20,31,over # branch after pointer table
base:
.align 3
.LCgot: .quad _got-base+0x8000
.LCstack: .quad _stack+STACKSIZE-0x80-base
over:
mflr r8 # gpr 8 is the base
ld r1,.LCstack-base(r8) # load new stack pointer
add r1, r1, r8 # add base
std r2, 64(r1) # save got
std r7, 56(r1) # save link register
ld r2, .LCgot-base(r8) # load got pointer
add r2, r2, r8 # add base
std r6, 0(r1) # save stack pointer
ld r6, .prom_entry_toc@toc(r2)
std r5, 0(r6) # Save prom handle
ld r10, .exit_sp_toc@toc(r2) # save stack pointer for exit call
std r1, 0(r10)
bl ._start_kernel # call kernel init code
the_end:
ld r4, 56(r1) # Restore link register
mtlr r4
ld r2, 64(r1) # restore got
ld r1, 0(r1)
blr
/*
* Function: _callback_entry
* Input: r6 start address of parameter string
* r7 length of parameter string.
*
* Description: If a client application wants to register a callback function,
* this function is registered w/ SLOF, not the application's function. SLOF
* passes the parameter string in Forth representation in R6 and R7. This
* function moves R6 to R3 and R7 to R4 and then calls callback_entry().
*
*/
C_ENTRY(_callback_entry)
# Save the LR
mflr r0
std r0, 16(r1)
# Reserve stack space
stdu r1, -32(r1)
# SLOF passes the parameters in Registers R6 and R7 but the target
# wants them in registers R3 and R4
mr r3, r6
mr r4, r7
# Branch to the callback_entry function
bl .callback_entry
# Destroy stack frame
ld r1, 0(r1)
# Restore LR
ld r0, 16(r1)
mtlr r0
# Return to caller
blr
.section ".bss"
_exit_sp: .quad 0
.global _prom_entry
_prom_entry: .quad 0
.section ".text"
C_ENTRY(_exit)
ld r1, .exit_sp_toc@toc(r2)
ld r1, 0(r1)
b the_end
.lcomm _stack,STACKSIZE,16
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