xref: /linux/arch/arm/mach-davinci/pm.h (revision 8eecf1c9929aef24e9e75280a39ed1ba3c64fb71)
1 /*
2  * TI DaVinci platform support for power management.
3  *
4  * Copyright (C) 2009 Texas Instruments, Inc. https://www.ti.com/
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation version 2.
9  *
10  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
11  * kind, whether express or implied; without even the implied warranty
12  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  */
15 #ifndef _MACH_DAVINCI_PM_H
16 #define _MACH_DAVINCI_PM_H
17 
18 /*
19  * Caution: Assembly code in sleep.S makes assumtion on the order
20  * of the members of this structure.
21  */
22 struct davinci_pm_config {
23 	void __iomem *ddr2_ctlr_base;
24 	void __iomem *ddrpsc_reg_base;
25 	int ddrpsc_num;
26 	void __iomem *ddrpll_reg_base;
27 	void __iomem *deepsleep_reg;
28 	void __iomem *cpupll_reg_base;
29 	/*
30 	 * Note on SLEEPCOUNT:
31 	 * The SLEEPCOUNT feature is mainly intended for cases in which
32 	 * the internal oscillator is used. The internal oscillator is
33 	 * fully disabled in deep sleep mode.  When you exist deep sleep
34 	 * mode, the oscillator will be turned on and will generate very
35 	 * small oscillations which will not be detected by the deep sleep
36 	 * counter.  Eventually those oscillations will grow to an amplitude
37 	 * large enough to start incrementing the deep sleep counter.
38 	 * In this case recommendation from hardware engineers is that the
39 	 * SLEEPCOUNT be set to 4096.  This means that 4096 valid clock cycles
40 	 * must be detected before the clock is passed to the rest of the
41 	 * system.
42 	 * In the case that the internal oscillator is not used and the
43 	 * clock is generated externally, the SLEEPCOUNT value can be very
44 	 * small since the clock input is assumed to be stable before SoC
45 	 * is taken out of deepsleep mode.  A value of 128 would be more than
46 	 * adequate.
47 	 */
48 	int sleepcount;
49 };
50 
51 extern unsigned int davinci_cpu_suspend_sz;
52 extern void davinci_cpu_suspend(struct davinci_pm_config *);
53 
54 #endif
55