xref: /openbmc/linux/tools/testing/selftests/arm64/mte/mte_helper.S (revision 4f2c0a4acffbec01079c28f839422e64ddeff004)

/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (C) 2020 ARM Limited */

#include "mte_def.h"

.arch	armv8.5-a+memtag

#define ENTRY(name) \
	.globl name ;\
	.p2align 2;\
	.type name, @function ;\
name:

#define ENDPROC(name) \
	.size name, .-name ;

	.text
/*
 * mte_insert_random_tag: Insert random tag and might be same as the source tag if
 *			  the source pointer has it.
 * Input:
 *		x0 - source pointer with a tag/no-tag
 * Return:
 *		x0 - pointer with random tag
 */
ENTRY(mte_insert_random_tag)
	irg	x0, x0, xzr
	ret
ENDPROC(mte_insert_random_tag)

/*
 * mte_insert_new_tag: Insert new tag and different from the source tag if
 *		       source pointer has it.
 * Input:
 *		x0 - source pointer with a tag/no-tag
 * Return:
 *		x0 - pointer with random tag
 */
ENTRY(mte_insert_new_tag)
	gmi	x1, x0, xzr
	irg	x0, x0, x1
	ret
ENDPROC(mte_insert_new_tag)

/*
 * mte_get_tag_address: Get the tag from given address.
 * Input:
 *		x0 - source pointer
 * Return:
 *		x0 - pointer with appended tag
 */
ENTRY(mte_get_tag_address)
	ldg	x0, [x0]
	ret
ENDPROC(mte_get_tag_address)

/*
 * mte_set_tag_address_range: Set the tag range from the given address
 * Input:
 *		x0 - source pointer with tag data
 *		x1 - range
 * Return:
 *		none
 */
ENTRY(mte_set_tag_address_range)
	cbz	x1, 2f
1:
	stg	x0, [x0, #0x0]
	add	x0, x0, #MT_GRANULE_SIZE
	sub	x1, x1, #MT_GRANULE_SIZE
	cbnz	x1, 1b
2:
	ret
ENDPROC(mte_set_tag_address_range)

/*
 * mt_clear_tag_address_range: Clear the tag range from the given address
 * Input:
 *		x0 - source pointer with tag data
 *		x1 - range
 * Return:
 *		none
 */
ENTRY(mte_clear_tag_address_range)
	cbz	x1, 2f
1:
	stzg	x0, [x0, #0x0]
	add	x0, x0, #MT_GRANULE_SIZE
	sub	x1, x1, #MT_GRANULE_SIZE
	cbnz	x1, 1b
2:
	ret
ENDPROC(mte_clear_tag_address_range)

/*
 * mte_enable_pstate_tco: Enable PSTATE.TCO (tag check override) field
 * Input:
 *		none
 * Return:
 *		none
 */
ENTRY(mte_enable_pstate_tco)
	msr	tco, #MT_PSTATE_TCO_EN
	ret
ENDPROC(mte_enable_pstate_tco)

/*
 * mte_disable_pstate_tco: Disable PSTATE.TCO (tag check override) field
 * Input:
 *		none
 * Return:
 *		none
 */
ENTRY(mte_disable_pstate_tco)
	msr	tco, #MT_PSTATE_TCO_DIS
	ret
ENDPROC(mte_disable_pstate_tco)

/*
 * mte_get_pstate_tco: Get PSTATE.TCO (tag check override) field
 * Input:
 *		none
 * Return:
 *		x0
 */
ENTRY(mte_get_pstate_tco)
	mrs	x0, tco
	ubfx	x0, x0, #MT_PSTATE_TCO_SHIFT, #1
	ret
ENDPROC(mte_get_pstate_tco)