xref: /OK3568_Linux_fs/u-boot/arch/arm/include/asm/arch-armv7/generictimer.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * Copyright (C) 2013 - ARM Ltd
3*4882a593Smuzhiyun  * Author: Marc Zyngier <marc.zyngier@arm.com>
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Based on code by Carl van Schaik <carl@ok-labs.com>.
6*4882a593Smuzhiyun  *
7*4882a593Smuzhiyun  * This program is free software; you can redistribute it and/or modify
8*4882a593Smuzhiyun  * it under the terms of the GNU General Public License version 2 as
9*4882a593Smuzhiyun  * published by the Free Software Foundation.
10*4882a593Smuzhiyun  *
11*4882a593Smuzhiyun  * This program is distributed in the hope that it will be useful,
12*4882a593Smuzhiyun  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13*4882a593Smuzhiyun  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14*4882a593Smuzhiyun  * GNU General Public License for more details.
15*4882a593Smuzhiyun  *
16*4882a593Smuzhiyun  * You should have received a copy of the GNU General Public License
17*4882a593Smuzhiyun  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
18*4882a593Smuzhiyun  */
19*4882a593Smuzhiyun 
20*4882a593Smuzhiyun #ifndef _GENERICTIMER_H_
21*4882a593Smuzhiyun #define _GENERICTIMER_H_
22*4882a593Smuzhiyun 
23*4882a593Smuzhiyun #ifdef __ASSEMBLY__
24*4882a593Smuzhiyun 
25*4882a593Smuzhiyun /*
26*4882a593Smuzhiyun  * This macro provide a physical timer that can be used for delay in the code.
27*4882a593Smuzhiyun  * The macro is moved from sunxi/psci_sun7i.S
28*4882a593Smuzhiyun  *
29*4882a593Smuzhiyun  * reg: is used in this macro.
30*4882a593Smuzhiyun  * ticks: The freq is based on generic timer.
31*4882a593Smuzhiyun  */
32*4882a593Smuzhiyun .macro	timer_wait	reg, ticks
33*4882a593Smuzhiyun 	movw	\reg, #(\ticks & 0xffff)
34*4882a593Smuzhiyun 	movt	\reg, #(\ticks >> 16)
35*4882a593Smuzhiyun 	mcr	p15, 0, \reg, c14, c2, 0
36*4882a593Smuzhiyun 	isb
37*4882a593Smuzhiyun 	mov	\reg, #3
38*4882a593Smuzhiyun 	mcr	p15, 0, \reg, c14, c2, 1
39*4882a593Smuzhiyun 1 :	isb
40*4882a593Smuzhiyun 	mrc	p15, 0, \reg, c14, c2, 1
41*4882a593Smuzhiyun 	ands	\reg, \reg, #4
42*4882a593Smuzhiyun 	bne	1b
43*4882a593Smuzhiyun 	mov	\reg, #0
44*4882a593Smuzhiyun 	mcr	p15, 0, \reg, c14, c2, 1
45*4882a593Smuzhiyun 	isb
46*4882a593Smuzhiyun .endm
47*4882a593Smuzhiyun 
48*4882a593Smuzhiyun #endif /* __ASSEMBLY__ */
49*4882a593Smuzhiyun 
50*4882a593Smuzhiyun #endif /* _GENERICTIMER_H_ */
51