xref: /linux/arch/arm/common/secure_cntvoff.S (revision 312b62b6610cabea4cb535fd4889c41e9a84afca)
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2014 Renesas Electronics Corporation
4 *
5 * Initialization of CNTVOFF register from secure mode
6 *
7 */
8
9#include <linux/linkage.h>
10#include <asm/assembler.h>
11
12ENTRY(secure_cntvoff_init)
13	.arch	armv7-a
14	/*
15	 * CNTVOFF has to be initialized either from non-secure Hypervisor
16	 * mode or secure Monitor mode with SCR.NS==1. If TrustZone is enabled
17	 * then it should be handled by the secure code. The CPU must implement
18	 * the virtualization extensions.
19	 */
20	cps	#MON_MODE
21	mrc	p15, 0, r1, c1, c1, 0		/* Get Secure Config */
22	orr	r0, r1, #1
23	mcr	p15, 0, r0, c1, c1, 0		/* Set Non Secure bit */
24	isb
25	mov	r0, #0
26	mcrr	p15, 4, r0, r0, c14		/* CNTVOFF = 0 */
27	isb
28	mcr	p15, 0, r1, c1, c1, 0		/* Set Secure bit */
29	isb
30	cps	#SVC_MODE
31	ret	lr
32ENDPROC(secure_cntvoff_init)
33