xref: /openbmc/linux/arch/powerpc/include/asm/cpuidle.h (revision 7aacf86b)
1 #ifndef _ASM_POWERPC_CPUIDLE_H
2 #define _ASM_POWERPC_CPUIDLE_H
3 
4 #ifdef CONFIG_PPC_POWERNV
5 /* Thread state used in powernv idle state management */
6 #define PNV_THREAD_RUNNING              0
7 #define PNV_THREAD_NAP                  1
8 #define PNV_THREAD_SLEEP                2
9 #define PNV_THREAD_WINKLE               3
10 
11 /*
12  * Core state used in powernv idle for POWER8.
13  *
14  * The lock bit synchronizes updates to the state, as well as parts of the
15  * sleep/wake code (see kernel/idle_book3s.S).
16  *
17  * Bottom 8 bits track the idle state of each thread. Bit is cleared before
18  * the thread executes an idle instruction (nap/sleep/winkle).
19  *
20  * Then there is winkle tracking. A core does not lose complete state
21  * until every thread is in winkle. So the winkle count field counts the
22  * number of threads in winkle (small window of false positives is okay
23  * around the sleep/wake, so long as there are no false negatives).
24  *
25  * When the winkle count reaches 8 (the COUNT_ALL_BIT becomes set), then
26  * the THREAD_WINKLE_BITS are set, which indicate which threads have not
27  * yet woken from the winkle state.
28  */
29 #define PNV_CORE_IDLE_LOCK_BIT			0x10000000
30 
31 #define PNV_CORE_IDLE_WINKLE_COUNT		0x00010000
32 #define PNV_CORE_IDLE_WINKLE_COUNT_ALL_BIT	0x00080000
33 #define PNV_CORE_IDLE_WINKLE_COUNT_BITS		0x000F0000
34 #define PNV_CORE_IDLE_THREAD_WINKLE_BITS_SHIFT	8
35 #define PNV_CORE_IDLE_THREAD_WINKLE_BITS	0x0000FF00
36 
37 #define PNV_CORE_IDLE_THREAD_BITS       	0x000000FF
38 
39 /*
40  * ============================ NOTE =================================
41  * The older firmware populates only the RL field in the psscr_val and
42  * sets the psscr_mask to 0xf. On such a firmware, the kernel sets the
43  * remaining PSSCR fields to default values as follows:
44  *
45  * - ESL and EC bits are to 1. So wakeup from any stop state will be
46  *   at vector 0x100.
47  *
48  * - MTL and PSLL are set to the maximum allowed value as per the ISA,
49  *    i.e. 15.
50  *
51  * - The Transition Rate, TR is set to the Maximum value 3.
52  */
53 #define PSSCR_HV_DEFAULT_VAL    (PSSCR_ESL | PSSCR_EC |		    \
54 				PSSCR_PSLL_MASK | PSSCR_TR_MASK |   \
55 				PSSCR_MTL_MASK)
56 
57 #define PSSCR_HV_DEFAULT_MASK   (PSSCR_ESL | PSSCR_EC |		    \
58 				PSSCR_PSLL_MASK | PSSCR_TR_MASK |   \
59 				PSSCR_MTL_MASK | PSSCR_RL_MASK)
60 #define PSSCR_EC_SHIFT    20
61 #define PSSCR_ESL_SHIFT   21
62 #define GET_PSSCR_EC(x)   (((x) & PSSCR_EC) >> PSSCR_EC_SHIFT)
63 #define GET_PSSCR_ESL(x)  (((x) & PSSCR_ESL) >> PSSCR_ESL_SHIFT)
64 #define GET_PSSCR_RL(x)   ((x) & PSSCR_RL_MASK)
65 
66 #define ERR_EC_ESL_MISMATCH		-1
67 #define ERR_DEEP_STATE_ESL_MISMATCH	-2
68 
69 #ifndef __ASSEMBLY__
70 extern u32 pnv_fastsleep_workaround_at_entry[];
71 extern u32 pnv_fastsleep_workaround_at_exit[];
72 
73 extern u64 pnv_first_deep_stop_state;
74 
75 unsigned long pnv_cpu_offline(unsigned int cpu);
76 int validate_psscr_val_mask(u64 *psscr_val, u64 *psscr_mask, u32 flags);
77 static inline void report_invalid_psscr_val(u64 psscr_val, int err)
78 {
79 	switch (err) {
80 	case ERR_EC_ESL_MISMATCH:
81 		pr_warn("Invalid psscr 0x%016llx : ESL,EC bits unequal",
82 			psscr_val);
83 		break;
84 	case ERR_DEEP_STATE_ESL_MISMATCH:
85 		pr_warn("Invalid psscr 0x%016llx : ESL cleared for deep stop-state",
86 			psscr_val);
87 	}
88 }
89 #endif
90 
91 #endif
92 
93 /* Idle state entry routines */
94 #ifdef	CONFIG_PPC_P7_NAP
95 #define IDLE_STATE_ENTER_SEQ(IDLE_INST)                         \
96 	/* Magic NAP/SLEEP/WINKLE mode enter sequence */	\
97 	std	r0,0(r1);					\
98 	ptesync;						\
99 	ld	r0,0(r1);					\
100 236:	cmpd	cr0,r0,r0;					\
101 	bne	236b;						\
102 	IDLE_INST;						\
103 
104 #define	IDLE_STATE_ENTER_SEQ_NORET(IDLE_INST)			\
105 	IDLE_STATE_ENTER_SEQ(IDLE_INST)                         \
106 	b	.
107 #endif /* CONFIG_PPC_P7_NAP */
108 
109 #endif
110