xref: /rk3399_ARM-atf/plat/rockchip/rk3399/drivers/m0/src/suspend.c (revision 51faada71a219a8b94cd8d8e423f0f22e9da4d8f)
1 /*
2  * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
6  *
7  * Redistributions of source code must retain the above copyright notice, this
8  * list of conditions and the following disclaimer.
9  *
10  * Redistributions in binary form must reproduce the above copyright notice,
11  * this list of conditions and the following disclaimer in the documentation
12  * and/or other materials provided with the distribution.
13  *
14  * Neither the name of ARM nor the names of its contributors may be used
15  * to endorse or promote products derived from this software without specific
16  * prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include <pmu_regs.h>
32 #include "rk3399_mcu.h"
33 
34 #define M0_SCR			0xe000ed10  /* System Control Register (SCR) */
35 
36 #define SCR_SLEEPDEEP_SHIFT	(1 << 2)
37 
38 void handle_suspend(void)
39 {
40 	unsigned int status_value;
41 
42 	while (1) {
43 		status_value = mmio_read_32(PMU_BASE + PMU_POWER_ST);
44 		if (status_value) {
45 			mmio_clrbits_32(PMU_BASE + PMU_PWRMODE_CON, 0x01);
46 			return;
47 		}
48 	}
49 
50 	/* m0 enter deep sleep mode */
51 	mmio_setbits_32(M0_SCR, SCR_SLEEPDEEP_SHIFT);
52 }
53