#
# Copyright (C) 2006 Martin Decky
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# - Redistributions of source code must retain the above copyright
#   notice, this list of conditions and the following disclaimer.
# - Redistributions in binary form must reproduce the above copyright
#   notice, this list of conditions and the following disclaimer in the
#   documentation and/or other materials provided with the distribution.
# - The name of the author may not be used to endorse or promote products
#   derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#

#define STACK_WINDOW_SAVE_AREA_SIZE     (16*8)

#define PSTATE_AM_BIT	8

.text

.global halt
.global memcpy
.global jump_to_kernel

halt:
	b halt
	nop
	
memcpy:
	.register       %g2, #scratch
        .register       %g3, #scratch
	add	%o1, 7, %g1
	and	%g1, -8, %g1
	cmp	%o1, %g1
	be,pn	%xcc, 3f
	add	%o0, 7, %g1
	mov	0, %g3
0:
	brz,pn	%o2, 2f
	mov	0, %g2
1:
	ldub	[%g3 + %o1], %g1
	add	%g2, 1, %g2
	cmp	%o2, %g2
	stb	%g1, [%g3 + %o0]
	bne,pt	%xcc, 1b
	mov	%g2, %g3
2:
	jmp	%o7 + 8			! exit point
	mov	%o1, %o0
3:
	and	%g1, -8, %g1
	cmp	%o0, %g1
	bne,pt	%xcc, 0b
	mov	0, %g3
	srlx	%o2, 3, %g4
	brz,pn	%g4, 5f
	mov	0, %g5
4:
	sllx	%g3, 3, %g2
	add	%g5, 1, %g3
	ldx	[%o1 + %g2], %g1
	mov	%g3, %g5
	cmp	%g4, %g3
	bne,pt	%xcc, 4b
	stx	%g1, [%o0 + %g2]
5:
	and	%o2, 7, %o2
	brz,pn	%o2, 2b
	sllx	%g4, 3, %g1
	mov	0, %g2
	add	%g1, %o0, %o0
	add	%g1, %o1, %g4
	mov	0, %g3
6:
	ldub	[%g2 + %g4], %g1
	stb	%g1, [%g2 + %o0]
	add	%g3, 1, %g2
	cmp	%o2, %g2
	bne,pt	%xcc, 6b
	mov	%g2, %g3

	jmp	%o7 + 8			! exit point
	mov	%o1, %o0

jump_to_kernel:
	set ofw_cif, %l0
	jmp %o0				! jump to kernel
	ldx [%l0], %o4			! pass OpenFirmware address in %o4

.global ofw
ofw:
	save %sp, -STACK_WINDOW_SAVE_AREA_SIZE, %sp
	set ofw_cif, %l0
	ldx [%l0], %l0

	rdpr  %pstate, %l1
	and  %l1, ~PSTATE_AM_BIT, %l2
	wrpr  %l2, 0, %pstate
    
	jmpl %l0, %o7
	mov %i0, %o0

	wrpr %l1, 0, %pstate

	ret
	restore %o0, 0, %o0