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#

# Copyright (c) 2005 Jakub Jermar

# 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.

#

#include <arch/arch.h>

#include <arch/stack.h>

#include <arch/regdef.h>

#include <arch/mm/mmu.h>

.text

.register       %g2, #scratch

.register       %g3, #scratch

/*

 * This is the assembly language version of our _memcpy() generated by gcc.

 */

.global memcpy

memcpy:

	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

/*

 * Almost the same as memcpy() except the loads are from userspace.

 */

.global memcpy_from_uspace

memcpy_from_uspace:

	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:

	lduba	[%g3 + %o1] ASI_AIUS, %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

	ldxa	[%o1 + %g2] ASI_AIUS, %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:

	lduba	[%g2 + %g4] ASI_AIUS, %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

/*

 * Almost the same as memcpy() except the stores are to userspace.

 */

.global memcpy_to_uspace

memcpy_to_uspace:

	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

	stba	%g1, [%g3 + %o0] ASI_AIUS

	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

	stxa	%g1, [%o0 + %g2] ASI_AIUS

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

	stba	%g1, [%g2 + %o0] ASI_AIUS

	add	%g3, 1, %g2

	cmp	%o2, %g2

	bne,pt	%xcc, 6b

	mov	%g2, %g3

	jmp	%o7 + 8			! exit point

	mov	%o1, %o0

.global memcpy_from_uspace_failover_address

.global memcpy_to_uspace_failover_address

memcpy_from_uspace_failover_address:

memcpy_to_uspace_failover_address:

	jmp	%o7 + 8			! exit point

	mov	%g0, %o0		! return 0 on failure

.global memsetb

memsetb:

	b _memsetb

	nop

.macro WRITE_ALTERNATE_REGISTER reg, bit

	rdpr %pstate, %g1				! save PSTATE.PEF

	wrpr %g0, (\bit | PSTATE_PRIV_BIT), %pstate

	mov %o0, \reg

	wrpr %g0, PSTATE_PRIV_BIT, %pstate

	retl

	wrpr %g1, 0, %pstate				! restore PSTATE.PEF

.endm

.macro READ_ALTERNATE_REGISTER reg, bit

	rdpr %pstate, %g1				! save PSTATE.PEF

	wrpr %g0, (\bit | PSTATE_PRIV_BIT), %pstate

	mov \reg, %o0

	wrpr %g0, PSTATE_PRIV_BIT, %pstate

	retl

	wrpr %g1, 0, %pstate				! restore PSTATE.PEF

.endm

.global write_to_ag_g6

write_to_ag_g6:

	WRITE_ALTERNATE_REGISTER %g6, PSTATE_AG_BIT

.global write_to_ag_g7

write_to_ag_g7:

	WRITE_ALTERNATE_REGISTER %g7, PSTATE_AG_BIT

.global write_to_ig_g6

write_to_ig_g6:

	WRITE_ALTERNATE_REGISTER %g6, PSTATE_IG_BIT

.global read_from_ag_g7

read_from_ag_g7:

	READ_ALTERNATE_REGISTER %g7, PSTATE_AG_BIT

/** Switch to userspace.

 *

 * %o0	Userspace entry address.

 * %o1	Userspace stack pointer address.

 * %o2  Userspace address of uarg structure.

 */

.global switch_to_userspace

switch_to_userspace:

	save %o1, -STACK_WINDOW_SAVE_AREA_SIZE, %sp

	flushw

	wrpr %g0, 0, %cleanwin		! avoid information leak

	mov %i2, %o0			! uarg

	xor %o1, %o1, %o1		! %o1 is defined to hold pcb_ptr

					! set it to 0

	clr %i2

	clr %i3

	clr %i4

	clr %i5

	clr %i6

	wrpr %g0, 1, %tl		! enforce mapping via nucleus

	rdpr %cwp, %g1

	wrpr %g1, TSTATE_IE_BIT, %tstate

	wrpr %i0, 0, %tnpc

	/*

	 * Set primary context according to secondary context.

	 * Secondary context has been already installed by

	 * higher-level functions.

	 */

	wr %g0, ASI_DMMU, %asi

	ldxa [VA_SECONDARY_CONTEXT_REG] %asi, %g1

	stxa %g1, [VA_PRIMARY_CONTEXT_REG] %asi

	flush %i7

	/*

	 * Spills and fills will be handled by the userspace handlers.

	 */

	wrpr %g0, WSTATE_OTHER(0) | WSTATE_NORMAL(1), %wstate

	done				! jump to userspace