xref: /openbmc/linux/arch/mips/include/asm/pm-cps.h (revision 9b93eb47)
1 /*
2  * Copyright (C) 2014 Imagination Technologies
3  * Author: Paul Burton <paul.burton@mips.com>
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License as published by the
7  * Free Software Foundation;  either version 2 of the  License, or (at your
8  * option) any later version.
9  */
10 
11 #ifndef __MIPS_ASM_PM_CPS_H__
12 #define __MIPS_ASM_PM_CPS_H__
13 
14 /*
15  * The CM & CPC can only handle coherence & power control on a per-core basis,
16  * thus in an MT system the VP(E)s within each core are coupled and can only
17  * enter or exit states requiring CM or CPC assistance in unison.
18  */
19 #if defined(CONFIG_CPU_MIPSR6)
20 # define coupled_coherence cpu_has_vp
21 #elif defined(CONFIG_MIPS_MT)
22 # define coupled_coherence cpu_has_mipsmt
23 #else
24 # define coupled_coherence 0
25 #endif
26 
27 /* Enumeration of possible PM states */
28 enum cps_pm_state {
29 	CPS_PM_NC_WAIT,		/* MIPS wait instruction, non-coherent */
30 	CPS_PM_CLOCK_GATED,	/* Core clock gated */
31 	CPS_PM_POWER_GATED,	/* Core power gated */
32 	CPS_PM_STATE_COUNT,
33 };
34 
35 /**
36  * cps_pm_support_state - determine whether the system supports a PM state
37  * @state: the state to test for support
38  *
39  * Returns true if the system supports the given state, otherwise false.
40  */
41 extern bool cps_pm_support_state(enum cps_pm_state state);
42 
43 /**
44  * cps_pm_enter_state - enter a PM state
45  * @state: the state to enter
46  *
47  * Enter the given PM state. If coupled_coherence is non-zero then it is
48  * expected that this function be called at approximately the same time on
49  * each coupled CPU. Returns 0 on successful entry & exit, otherwise -errno.
50  */
51 extern int cps_pm_enter_state(enum cps_pm_state state);
52 
53 #endif /* __MIPS_ASM_PM_CPS_H__ */
54