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1/*
2 * Copyright (C) 1996-2000 Russell King - Converted to ARM.
3 * Original Copyright (C) 1995 Linus Torvalds
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 */
9#include <linux/cpu.h>
10#include <linux/delay.h>
11#include <linux/reboot.h>
12
13#include <asm/cacheflush.h>
14#include <asm/idmap.h>
15
16#include "reboot.h"
17
18typedef void (*phys_reset_t)(unsigned long);
19
20/*
21 * Function pointers to optional machine specific functions
22 */
23void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
24void (*pm_power_off)(void);
25EXPORT_SYMBOL(pm_power_off);
26
27/*
28 * A temporary stack to use for CPU reset. This is static so that we
29 * don't clobber it with the identity mapping. When running with this
30 * stack, any references to the current task *will not work* so you
31 * should really do as little as possible before jumping to your reset
32 * code.
33 */
34static u64 soft_restart_stack[16];
35
36static void __soft_restart(void *addr)
37{
38 phys_reset_t phys_reset;
39
40 /* Take out a flat memory mapping. */
41 setup_mm_for_reboot();
42
43 /* Clean and invalidate caches */
44 flush_cache_all();
45
46 /* Turn off caching */
47 cpu_proc_fin();
48
49 /* Push out any further dirty data, and ensure cache is empty */
50 flush_cache_all();
51
52 /* Switch to the identity mapping. */
53 phys_reset = (phys_reset_t)virt_to_idmap(cpu_reset);
54 phys_reset((unsigned long)addr);
55
56 /* Should never get here. */
57 BUG();
58}
59
60void _soft_restart(unsigned long addr, bool disable_l2)
61{
62 u64 *stack = soft_restart_stack + ARRAY_SIZE(soft_restart_stack);
63
64 /* Disable interrupts first */
65 raw_local_irq_disable();
66 local_fiq_disable();
67
68 /* Disable the L2 if we're the last man standing. */
69 if (disable_l2)
70 outer_disable();
71
72 /* Change to the new stack and continue with the reset. */
73 call_with_stack(__soft_restart, (void *)addr, (void *)stack);
74
75 /* Should never get here. */
76 BUG();
77}
78
79void soft_restart(unsigned long addr)
80{
81 _soft_restart(addr, num_online_cpus() == 1);
82}
83
84/*
85 * Called by kexec, immediately prior to machine_kexec().
86 *
87 * This must completely disable all secondary CPUs; simply causing those CPUs
88 * to execute e.g. a RAM-based pin loop is not sufficient. This allows the
89 * kexec'd kernel to use any and all RAM as it sees fit, without having to
90 * avoid any code or data used by any SW CPU pin loop. The CPU hotplug
91 * functionality embodied in disable_nonboot_cpus() to achieve this.
92 */
93void machine_shutdown(void)
94{
95 disable_nonboot_cpus();
96}
97
98/*
99 * Halting simply requires that the secondary CPUs stop performing any
100 * activity (executing tasks, handling interrupts). smp_send_stop()
101 * achieves this.
102 */
103void machine_halt(void)
104{
105 local_irq_disable();
106 smp_send_stop();
107
108 local_irq_disable();
109 while (1);
110}
111
112/*
113 * Power-off simply requires that the secondary CPUs stop performing any
114 * activity (executing tasks, handling interrupts). smp_send_stop()
115 * achieves this. When the system power is turned off, it will take all CPUs
116 * with it.
117 */
118void machine_power_off(void)
119{
120 local_irq_disable();
121 smp_send_stop();
122
123 if (pm_power_off)
124 pm_power_off();
125}
126
127/*
128 * Restart requires that the secondary CPUs stop performing any activity
129 * while the primary CPU resets the system. Systems with a single CPU can
130 * use soft_restart() as their machine descriptor's .restart hook, since that
131 * will cause the only available CPU to reset. Systems with multiple CPUs must
132 * provide a HW restart implementation, to ensure that all CPUs reset at once.
133 * This is required so that any code running after reset on the primary CPU
134 * doesn't have to co-ordinate with other CPUs to ensure they aren't still
135 * executing pre-reset code, and using RAM that the primary CPU's code wishes
136 * to use. Implementing such co-ordination would be essentially impossible.
137 */
138void machine_restart(char *cmd)
139{
140 local_irq_disable();
141 smp_send_stop();
142
143 if (arm_pm_restart)
144 arm_pm_restart(reboot_mode, cmd);
145 else
146 do_kernel_restart(cmd);
147
148 /* Give a grace period for failure to restart of 1s */
149 mdelay(1000);
150
151 /* Whoops - the platform was unable to reboot. Tell the user! */
152 printk("Reboot failed -- System halted\n");
153 local_irq_disable();
154 while (1);
155}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 1996-2000 Russell King - Converted to ARM.
4 * Original Copyright (C) 1995 Linus Torvalds
5 */
6#include <linux/cpu.h>
7#include <linux/delay.h>
8#include <linux/reboot.h>
9
10#include <asm/cacheflush.h>
11#include <asm/idmap.h>
12#include <asm/virt.h>
13#include <asm/system_misc.h>
14
15#include "reboot.h"
16
17typedef void (*phys_reset_t)(unsigned long, bool);
18
19/*
20 * Function pointers to optional machine specific functions
21 */
22void (*pm_power_off)(void);
23EXPORT_SYMBOL(pm_power_off);
24
25/*
26 * A temporary stack to use for CPU reset. This is static so that we
27 * don't clobber it with the identity mapping. When running with this
28 * stack, any references to the current task *will not work* so you
29 * should really do as little as possible before jumping to your reset
30 * code.
31 */
32static u64 soft_restart_stack[16];
33
34static void __soft_restart(void *addr)
35{
36 phys_reset_t phys_reset;
37
38 /* Take out a flat memory mapping. */
39 setup_mm_for_reboot();
40
41 /* Clean and invalidate caches */
42 flush_cache_all();
43
44 /* Turn off caching */
45 cpu_proc_fin();
46
47 /* Push out any further dirty data, and ensure cache is empty */
48 flush_cache_all();
49
50 /* Switch to the identity mapping. */
51 phys_reset = (phys_reset_t)virt_to_idmap(cpu_reset);
52
53 /* original stub should be restored by kvm */
54 phys_reset((unsigned long)addr, is_hyp_mode_available());
55
56 /* Should never get here. */
57 BUG();
58}
59
60void _soft_restart(unsigned long addr, bool disable_l2)
61{
62 u64 *stack = soft_restart_stack + ARRAY_SIZE(soft_restart_stack);
63
64 /* Disable interrupts first */
65 raw_local_irq_disable();
66 local_fiq_disable();
67
68 /* Disable the L2 if we're the last man standing. */
69 if (disable_l2)
70 outer_disable();
71
72 /* Change to the new stack and continue with the reset. */
73 call_with_stack(__soft_restart, (void *)addr, (void *)stack);
74
75 /* Should never get here. */
76 BUG();
77}
78
79void soft_restart(unsigned long addr)
80{
81 _soft_restart(addr, num_online_cpus() == 1);
82}
83
84/*
85 * Called by kexec, immediately prior to machine_kexec().
86 *
87 * This must completely disable all secondary CPUs; simply causing those CPUs
88 * to execute e.g. a RAM-based pin loop is not sufficient. This allows the
89 * kexec'd kernel to use any and all RAM as it sees fit, without having to
90 * avoid any code or data used by any SW CPU pin loop. The CPU hotplug
91 * functionality embodied in smp_shutdown_nonboot_cpus() to achieve this.
92 */
93void machine_shutdown(void)
94{
95 smp_shutdown_nonboot_cpus(reboot_cpu);
96}
97
98/*
99 * Halting simply requires that the secondary CPUs stop performing any
100 * activity (executing tasks, handling interrupts). smp_send_stop()
101 * achieves this.
102 */
103void machine_halt(void)
104{
105 local_irq_disable();
106 smp_send_stop();
107 while (1);
108}
109
110/*
111 * Power-off simply requires that the secondary CPUs stop performing any
112 * activity (executing tasks, handling interrupts). smp_send_stop()
113 * achieves this. When the system power is turned off, it will take all CPUs
114 * with it.
115 */
116void machine_power_off(void)
117{
118 local_irq_disable();
119 smp_send_stop();
120 do_kernel_power_off();
121}
122
123/*
124 * Restart requires that the secondary CPUs stop performing any activity
125 * while the primary CPU resets the system. Systems with a single CPU can
126 * use soft_restart() as their machine descriptor's .restart hook, since that
127 * will cause the only available CPU to reset. Systems with multiple CPUs must
128 * provide a HW restart implementation, to ensure that all CPUs reset at once.
129 * This is required so that any code running after reset on the primary CPU
130 * doesn't have to co-ordinate with other CPUs to ensure they aren't still
131 * executing pre-reset code, and using RAM that the primary CPU's code wishes
132 * to use. Implementing such co-ordination would be essentially impossible.
133 */
134void machine_restart(char *cmd)
135{
136 local_irq_disable();
137 smp_send_stop();
138
139 do_kernel_restart(cmd);
140
141 /* Give a grace period for failure to restart of 1s */
142 mdelay(1000);
143
144 /* Whoops - the platform was unable to reboot. Tell the user! */
145 printk("Reboot failed -- System halted\n");
146 while (1);
147}