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nv-tegra.nvidia.com / linux-5.10 / f7354ccac844da7b1af8cc4f09da330fa3e960e4 / . / arch / powerpc / kernel / idle_book3e.S
blob: 4e0d94d02030afb2a59da4898a6d90da9e54c457 [file] [log] [blame]
Benjamin Herrenschmidt34d97e072010-07-14 14:12:16 +1000[diff] [blame]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>
Stuart Yoderf0709862013-02-08 13:22:56 -0600[diff] [blame]19#include <asm/epapr_hcalls.h>
Madhavan Srinivasanc2e480b2017-12-20 09:25:42 +0530[diff] [blame]20#include <asm/hw_irq.h>
Benjamin Herrenschmidt34d97e072010-07-14 14:12:16 +1000[diff] [blame]21
22/* 64-bit version only for now */
23#ifdef CONFIG_PPC64
24
Stuart Yoderf0709862013-02-08 13:22:56 -0600[diff] [blame]25.macro BOOK3E_IDLE name loop
26_GLOBAL(\name)
Benjamin Herrenschmidt34d97e072010-07-14 14:12:16 +1000[diff] [blame]27 /* Save LR for later */
28 mflr r0
29 std r0,16(r1)
30
31 /* Hard disable interrupts */
32 wrteei 0
33
34 /* Now check if an interrupt came in while we were soft disabled
Benjamin Herrenschmidt7230c562012-03-06 18:27:59 +1100[diff] [blame]35 * since we may otherwise lose it (doorbells etc...).
Benjamin Herrenschmidt34d97e072010-07-14 14:12:16 +1000[diff] [blame]36 */
Benjamin Herrenschmidt7230c562012-03-06 18:27:59 +1100[diff] [blame]37 lbz r3,PACAIRQHAPPENED(r13)
Benjamin Herrenschmidt34d97e072010-07-14 14:12:16 +1000[diff] [blame]38 cmpwi cr0,r3,0
Nicholas Piggin9b81c022018-06-03 22:24:32 +1000[diff] [blame]39 bne 2f
Benjamin Herrenschmidt34d97e072010-07-14 14:12:16 +1000[diff] [blame]40
Benjamin Herrenschmidt7230c562012-03-06 18:27:59 +1100[diff] [blame]41 /* Now we are going to mark ourselves as soft and hard enabled in
Benjamin Herrenschmidt34d97e072010-07-14 14:12:16 +1000[diff] [blame]42 * order to be able to take interrupts while asleep. We inform lockdep
43 * of that. We don't actually turn interrupts on just yet tho.
44 */
45#ifdef CONFIG_TRACE_IRQFLAGS
46 stdu r1,-128(r1)
Anton Blanchardb1576fe2014-02-04 16:04:35 +1100[diff] [blame]47 bl trace_hardirqs_on
Benjamin Herrenschmidt7230c562012-03-06 18:27:59 +1100[diff] [blame]48 addi r1,r1,128
Benjamin Herrenschmidt34d97e072010-07-14 14:12:16 +1000[diff] [blame]49#endif
Madhavan Srinivasanc2e480b2017-12-20 09:25:42 +0530[diff] [blame]50 li r0,IRQS_ENABLED
Madhavan Srinivasan4e26bc42017-12-20 09:25:50 +0530[diff] [blame]51 stb r0,PACAIRQSOFTMASK(r13)
Benjamin Herrenschmidt34d97e072010-07-14 14:12:16 +1000[diff] [blame]52
53 /* Interrupts will make use return to LR, so get something we want
54 * in there
55 */
56 bl 1f
57
Benjamin Herrenschmidt7230c562012-03-06 18:27:59 +1100[diff] [blame]58 /* And return (interrupts are on) */
Benjamin Herrenschmidt34d97e072010-07-14 14:12:16 +1000[diff] [blame]59 ld r0,16(r1)
60 mtlr r0
61 blr
62
631: /* Let's set the _TLF_NAPPING flag so interrupts make us return
64 * to the right spot
65 */
Stuart Yoder9778b692012-07-05 04:41:35 +0000[diff] [blame]66 CURRENT_THREAD_INFO(r11, r1)
Benjamin Herrenschmidt34d97e072010-07-14 14:12:16 +1000[diff] [blame]67 ld r10,TI_LOCAL_FLAGS(r11)
68 ori r10,r10,_TLF_NAPPING
69 std r10,TI_LOCAL_FLAGS(r11)
70
71 /* We can now re-enable hard interrupts and go to sleep */
72 wrteei 1
Stuart Yoderf0709862013-02-08 13:22:56 -0600[diff] [blame]73 \loop
74
Nicholas Piggin9b81c022018-06-03 22:24:32 +1000[diff] [blame]752:
76 lbz r10,PACAIRQHAPPENED(r13)
77 ori r10,r10,PACA_IRQ_HARD_DIS
78 stb r10,PACAIRQHAPPENED(r13)
79 blr
Stuart Yoderf0709862013-02-08 13:22:56 -0600[diff] [blame]80.endm
81
82.macro BOOK3E_IDLE_LOOP
831:
84 PPC_WAIT(0)
Benjamin Herrenschmidt34d97e072010-07-14 14:12:16 +1000[diff] [blame]85 b 1b
Stuart Yoderf0709862013-02-08 13:22:56 -0600[diff] [blame]86.endm
87
88/* epapr_ev_idle_start below is patched with the proper hcall
89 opcodes during kernel initialization */
90.macro EPAPR_EV_IDLE_LOOP
91idle_loop:
92 LOAD_REG_IMMEDIATE(r11, EV_HCALL_TOKEN(EV_IDLE))
93
94.global epapr_ev_idle_start
95epapr_ev_idle_start:
96 li r3, -1
97 nop
98 nop
99 nop
100 b idle_loop
101.endm
102
103BOOK3E_IDLE epapr_ev_idle EPAPR_EV_IDLE_LOOP
104
105BOOK3E_IDLE book3e_idle BOOK3E_IDLE_LOOP
Benjamin Herrenschmidt34d97e072010-07-14 14:12:16 +1000[diff] [blame]106
107#endif /* CONFIG_PPC64 */