]>
git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - arch/arm/mach-realview/hotplug.c
2 * linux/arch/arm/mach-realview/hotplug.c
4 * Copyright (C) 2002 ARM Ltd.
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/smp.h>
16 #include <asm/smp_plat.h>
18 static inline void cpu_enter_lowpower(void)
23 " mcr p15, 0, %1, c7, c5, 0\n"
24 " mcr p15, 0, %1, c7, c10, 4\n"
28 " mrc p15, 0, %0, c1, c0, 1\n"
29 " bic %0, %0, #0x20\n"
30 " mcr p15, 0, %0, c1, c0, 1\n"
31 " mrc p15, 0, %0, c1, c0, 0\n"
33 " mcr p15, 0, %0, c1, c0, 0\n"
35 : "r" (0), "Ir" (CR_C
)
39 static inline void cpu_leave_lowpower(void)
43 asm volatile( "mrc p15, 0, %0, c1, c0, 0\n"
45 " mcr p15, 0, %0, c1, c0, 0\n"
46 " mrc p15, 0, %0, c1, c0, 1\n"
47 " orr %0, %0, #0x20\n"
48 " mcr p15, 0, %0, c1, c0, 1\n"
54 static inline void platform_do_lowpower(unsigned int cpu
, int *spurious
)
57 * there is no power-control hardware on this platform, so all
58 * we can do is put the core into WFI; this is safe as the calling
59 * code will have already disabled interrupts
65 asm(".word 0xe320f003\n"
70 if (pen_release
== cpu_logical_map(cpu
)) {
72 * OK, proper wakeup, we're done
78 * Getting here, means that we have come out of WFI without
79 * having been woken up - this shouldn't happen
81 * Just note it happening - when we're woken, we can report
89 * platform-specific code to shutdown a CPU
91 * Called with IRQs disabled
93 void realview_cpu_die(unsigned int cpu
)
98 * we're ready for shutdown now, so do it
100 cpu_enter_lowpower();
101 platform_do_lowpower(cpu
, &spurious
);
104 * bring this CPU back into the world of cache
105 * coherency, and then restore interrupts
107 cpu_leave_lowpower();
110 pr_warn("CPU%u: %u spurious wakeup calls\n", cpu
, spurious
);