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1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * Copyright 2010 IBM Corp, Benjamin Herrenschmidt <benh@kernel.crashing.org>
4 *
5 * Generic idle routine for Book3E processors
6 */
7
8#include <linux/threads.h>
9#include <asm/reg.h>
10#include <asm/ppc_asm.h>
11#include <asm/asm-offsets.h>
12#include <asm/ppc-opcode.h>
13#include <asm/processor.h>
14#include <asm/thread_info.h>
15#include <asm/epapr_hcalls.h>
16#include <asm/hw_irq.h>
17
18/* 64-bit version only for now */
19#ifdef CONFIG_PPC64
20
21.macro BOOK3E_IDLE name loop
22_GLOBAL(\name)
23 /* Save LR for later */
24 mflr r0
25 std r0,16(r1)
26
27 /* Hard disable interrupts */
28 wrteei 0
29
30 /* Now check if an interrupt came in while we were soft disabled
31 * since we may otherwise lose it (doorbells etc...).
32 */
33 lbz r3,PACAIRQHAPPENED(r13)
34 cmpwi cr0,r3,0
35 bne 2f
36
37 /* Now we are going to mark ourselves as soft and hard enabled in
38 * order to be able to take interrupts while asleep. We inform lockdep
39 * of that. We don't actually turn interrupts on just yet tho.
40 */
41#ifdef CONFIG_TRACE_IRQFLAGS
42 stdu r1,-128(r1)
43 bl trace_hardirqs_on
44 addi r1,r1,128
45#endif
46 li r0,IRQS_ENABLED
47 stb r0,PACAIRQSOFTMASK(r13)
48
49 /* Interrupts will make use return to LR, so get something we want
50 * in there
51 */
52 bl 1f
53
54 /* And return (interrupts are on) */
55 ld r0,16(r1)
56 mtlr r0
57 blr
58
591: /* Let's set the _TLF_NAPPING flag so interrupts make us return
60 * to the right spot
61 */
62 ld r11, PACACURRENT(r13)
63 ld r10,TI_LOCAL_FLAGS(r11)
64 ori r10,r10,_TLF_NAPPING
65 std r10,TI_LOCAL_FLAGS(r11)
66
67 /* We can now re-enable hard interrupts and go to sleep */
68 wrteei 1
69 \loop
70
712:
72 lbz r10,PACAIRQHAPPENED(r13)
73 ori r10,r10,PACA_IRQ_HARD_DIS
74 stb r10,PACAIRQHAPPENED(r13)
75 blr
76.endm
77
78.macro BOOK3E_IDLE_LOOP
791:
80 PPC_WAIT(0)
81 b 1b
82.endm
83
84/* epapr_ev_idle_start below is patched with the proper hcall
85 opcodes during kernel initialization */
86.macro EPAPR_EV_IDLE_LOOP
87idle_loop:
88 LOAD_REG_IMMEDIATE(r11, EV_HCALL_TOKEN(EV_IDLE))
89
90.global epapr_ev_idle_start
91epapr_ev_idle_start:
92 li r3, -1
93 nop
94 nop
95 nop
96 b idle_loop
97.endm
98
99BOOK3E_IDLE epapr_ev_idle EPAPR_EV_IDLE_LOOP
100
101BOOK3E_IDLE book3e_idle BOOK3E_IDLE_LOOP
102
103#endif /* CONFIG_PPC64 */
1/*
2 * Copyright 2010 IBM Corp, Benjamin Herrenschmidt <benh@kernel.crashing.org>
3 *
4 * Generic idle routine for Book3E processors
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
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/threads.h>
13#include <asm/reg.h>
14#include <asm/ppc_asm.h>
15#include <asm/asm-offsets.h>
16#include <asm/ppc-opcode.h>
17#include <asm/processor.h>
18#include <asm/thread_info.h>
19
20/* 64-bit version only for now */
21#ifdef CONFIG_PPC64
22
23_GLOBAL(book3e_idle)
24 /* Save LR for later */
25 mflr r0
26 std r0,16(r1)
27
28 /* Hard disable interrupts */
29 wrteei 0
30
31 /* Now check if an interrupt came in while we were soft disabled
32 * since we may otherwise lose it (doorbells etc...). We know
33 * that since PACAHARDIRQEN will have been cleared in that case.
34 */
35 lbz r3,PACAHARDIRQEN(r13)
36 cmpwi cr0,r3,0
37 beqlr
38
39 /* Now we are going to mark ourselves as soft and hard enables in
40 * order to be able to take interrupts while asleep. We inform lockdep
41 * of that. We don't actually turn interrupts on just yet tho.
42 */
43#ifdef CONFIG_TRACE_IRQFLAGS
44 stdu r1,-128(r1)
45 bl .trace_hardirqs_on
46#endif
47 li r0,1
48 stb r0,PACASOFTIRQEN(r13)
49 stb r0,PACAHARDIRQEN(r13)
50
51 /* Interrupts will make use return to LR, so get something we want
52 * in there
53 */
54 bl 1f
55
56 /* Hard disable interrupts again */
57 wrteei 0
58
59 /* Mark them off again in the PACA as well */
60 li r0,0
61 stb r0,PACASOFTIRQEN(r13)
62 stb r0,PACAHARDIRQEN(r13)
63
64 /* Tell lockdep about it */
65#ifdef CONFIG_TRACE_IRQFLAGS
66 bl .trace_hardirqs_off
67 addi r1,r1,128
68#endif
69 ld r0,16(r1)
70 mtlr r0
71 blr
72
731: /* Let's set the _TLF_NAPPING flag so interrupts make us return
74 * to the right spot
75 */
76 clrrdi r11,r1,THREAD_SHIFT
77 ld r10,TI_LOCAL_FLAGS(r11)
78 ori r10,r10,_TLF_NAPPING
79 std r10,TI_LOCAL_FLAGS(r11)
80
81 /* We can now re-enable hard interrupts and go to sleep */
82 wrteei 1
831: PPC_WAIT(0)
84 b 1b
85
86#endif /* CONFIG_PPC64 */