1 /* linux arch/arm/mach-s5pv310/hotplug.c
3 * Based on linux/arch/arm/mach-realview/hotplug.c
5 * Copyright (C) 2002 ARM Ltd.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/smp.h>
16 #include <linux/completion.h>
19 #include <asm/cacheflush.h>
21 #include <mach/regs-pmu.h>
22 #include <mach/cpu_revision.h>
24 extern volatile int pen_release;
26 static DECLARE_COMPLETION(cpu_killed);
28 static void cpu_enter_lowpower(void)
34 " mcr p15, 0, %1, c7, c5, 0\n"
35 " mcr p15, 0, %1, c7, c10, 4\n"
39 " mrc p15, 0, %0, c1, c0, 1\n"
40 " bic %0, %0, #0x41\n"
41 " mcr p15, 0, %0, c1, c0, 1\n"
42 " mrc p15, 0, %0, c1, c0, 0\n"
43 " bic %0, %0, #0x04\n"
44 " mcr p15, 0, %0, c1, c0, 0\n"
50 static void cpu_leave_lowpower(void)
55 " mrc p15, 0, %0, c1, c0, 0\n"
56 " orr %0, %0, #0x04\n"
57 " mcr p15, 0, %0, c1, c0, 0\n"
58 " mrc p15, 0, %0, c1, c0, 1\n"
59 " orr %0, %0, #0x41\n"
60 " mcr p15, 0, %0, c1, c0, 1\n"
66 inline void platform_do_lowpower(unsigned int cpu)
69 /* make cpu1 to be turned off at next WFI command */
71 __raw_writel(0, S5P_ARM_CORE1_CONFIGURATION);
74 if (hard_smp_processor_id() == 0)
80 asm(".word 0xe320f003\n"
85 if (pen_release == cpu) {
87 * OK, proper wakeup, we're done
93 * getting here, means that we have come out of WFI without
94 * having been woken up - this shouldn't happen
96 * The trouble is, letting people know about this is not really
97 * possible, since we are currently running incoherently, and
98 * therefore cannot safely call printk() or anything else
101 printk(KERN_WARN "CPU%u: spurious wakeup call\n", cpu);
106 int platform_cpu_kill(unsigned int cpu)
108 return wait_for_completion_timeout(&cpu_killed, 5000);
112 * platform-specific code to shutdown a CPU
114 * Called with IRQs disabled
116 void platform_cpu_die(unsigned int cpu)
119 unsigned int this_cpu = hard_smp_processor_id();
121 if (cpu != this_cpu) {
122 printk(KERN_CRIT "Eek! platform_cpu_die running on %u, should be %u\n",
128 printk(KERN_NOTICE "CPU%u: shutdown\n", cpu);
129 complete(&cpu_killed);
132 * we're ready for shutdown now, so do it
134 cpu_enter_lowpower();
135 platform_do_lowpower(cpu);
138 * bring this CPU back into the world of cache
139 * coherency, and then restore interrupts
141 cpu_leave_lowpower();
144 int platform_cpu_disable(unsigned int cpu)
147 * we don't allow CPU 0 to be shutdown (it is still too special
148 * e.g. clock tick interrupts)
150 return cpu == 0 ? -EPERM : 0;