xref: /openbmc/linux/arch/arm/mach-davinci/pm.h (revision 2a9eb57e)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * TI DaVinci platform support for power management.
4  *
5  * Copyright (C) 2009 Texas Instruments, Inc. https://www.ti.com/
6  */
7 #ifndef _MACH_DAVINCI_PM_H
8 #define _MACH_DAVINCI_PM_H
9 
10 /*
11  * Caution: Assembly code in sleep.S makes assumtion on the order
12  * of the members of this structure.
13  */
14 struct davinci_pm_config {
15 	void __iomem *ddr2_ctlr_base;
16 	void __iomem *ddrpsc_reg_base;
17 	int ddrpsc_num;
18 	void __iomem *ddrpll_reg_base;
19 	void __iomem *deepsleep_reg;
20 	void __iomem *cpupll_reg_base;
21 	/*
22 	 * Note on SLEEPCOUNT:
23 	 * The SLEEPCOUNT feature is mainly intended for cases in which
24 	 * the internal oscillator is used. The internal oscillator is
25 	 * fully disabled in deep sleep mode.  When you exist deep sleep
26 	 * mode, the oscillator will be turned on and will generate very
27 	 * small oscillations which will not be detected by the deep sleep
28 	 * counter.  Eventually those oscillations will grow to an amplitude
29 	 * large enough to start incrementing the deep sleep counter.
30 	 * In this case recommendation from hardware engineers is that the
31 	 * SLEEPCOUNT be set to 4096.  This means that 4096 valid clock cycles
32 	 * must be detected before the clock is passed to the rest of the
33 	 * system.
34 	 * In the case that the internal oscillator is not used and the
35 	 * clock is generated externally, the SLEEPCOUNT value can be very
36 	 * small since the clock input is assumed to be stable before SoC
37 	 * is taken out of deepsleep mode.  A value of 128 would be more than
38 	 * adequate.
39 	 */
40 	int sleepcount;
41 };
42 
43 extern unsigned int davinci_cpu_suspend_sz;
44 extern void davinci_cpu_suspend(struct davinci_pm_config *);
45 
46 #endif
47