Kukjin Kim | 7d30e8b | 2011-02-14 16:33:10 +0900 | [diff] [blame] | 1 | /* linux arch/arm/mach-exynos4/hotplug.c |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 2 | * |
| 3 | * Cloned from linux/arch/arm/mach-realview/hotplug.c |
| 4 | * |
| 5 | * Copyright (C) 2002 ARM Ltd. |
| 6 | * All Rights Reserved |
| 7 | * |
| 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. |
| 11 | */ |
| 12 | |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/errno.h> |
| 15 | #include <linux/smp.h> |
JungHi Min | 911c29b | 2011-07-16 13:39:09 +0900 | [diff] [blame] | 16 | #include <linux/io.h> |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 17 | |
| 18 | #include <asm/cacheflush.h> |
Russell King | 15d07dc | 2012-03-28 18:30:01 +0100 | [diff] [blame] | 19 | #include <asm/cp15.h> |
Will Deacon | eb50439 | 2012-01-20 12:01:12 +0100 | [diff] [blame] | 20 | #include <asm/smp_plat.h> |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 21 | |
JungHi Min | 911c29b | 2011-07-16 13:39:09 +0900 | [diff] [blame] | 22 | #include <mach/regs-pmu.h> |
| 23 | |
Marc Zyngier | 06853ae | 2011-09-08 13:15:22 +0100 | [diff] [blame^] | 24 | #include "common.h" |
| 25 | |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 26 | extern volatile int pen_release; |
| 27 | |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 28 | static inline void cpu_enter_lowpower(void) |
| 29 | { |
| 30 | unsigned int v; |
| 31 | |
| 32 | flush_cache_all(); |
| 33 | asm volatile( |
| 34 | " mcr p15, 0, %1, c7, c5, 0\n" |
| 35 | " mcr p15, 0, %1, c7, c10, 4\n" |
| 36 | /* |
| 37 | * Turn off coherency |
| 38 | */ |
| 39 | " mrc p15, 0, %0, c1, c0, 1\n" |
Kukjin Kim | ad849a2 | 2011-02-28 20:35:33 +0900 | [diff] [blame] | 40 | " bic %0, %0, %3\n" |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 41 | " mcr p15, 0, %0, c1, c0, 1\n" |
| 42 | " mrc p15, 0, %0, c1, c0, 0\n" |
Russell King | 30b99d0 | 2011-01-14 12:06:26 +0000 | [diff] [blame] | 43 | " bic %0, %0, %2\n" |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 44 | " mcr p15, 0, %0, c1, c0, 0\n" |
| 45 | : "=&r" (v) |
Kukjin Kim | ad849a2 | 2011-02-28 20:35:33 +0900 | [diff] [blame] | 46 | : "r" (0), "Ir" (CR_C), "Ir" (0x40) |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 47 | : "cc"); |
| 48 | } |
| 49 | |
| 50 | static inline void cpu_leave_lowpower(void) |
| 51 | { |
| 52 | unsigned int v; |
| 53 | |
| 54 | asm volatile( |
| 55 | "mrc p15, 0, %0, c1, c0, 0\n" |
Russell King | e3d9c62 | 2010-12-19 11:36:33 +0000 | [diff] [blame] | 56 | " orr %0, %0, %1\n" |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 57 | " mcr p15, 0, %0, c1, c0, 0\n" |
| 58 | " mrc p15, 0, %0, c1, c0, 1\n" |
Kukjin Kim | ad849a2 | 2011-02-28 20:35:33 +0900 | [diff] [blame] | 59 | " orr %0, %0, %2\n" |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 60 | " mcr p15, 0, %0, c1, c0, 1\n" |
| 61 | : "=&r" (v) |
Kukjin Kim | ad849a2 | 2011-02-28 20:35:33 +0900 | [diff] [blame] | 62 | : "Ir" (CR_C), "Ir" (0x40) |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 63 | : "cc"); |
| 64 | } |
| 65 | |
Russell King | d445026 | 2010-12-19 11:30:43 +0000 | [diff] [blame] | 66 | static inline void platform_do_lowpower(unsigned int cpu, int *spurious) |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 67 | { |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 68 | for (;;) { |
JungHi Min | 911c29b | 2011-07-16 13:39:09 +0900 | [diff] [blame] | 69 | |
| 70 | /* make cpu1 to be turned off at next WFI command */ |
| 71 | if (cpu == 1) |
| 72 | __raw_writel(0, S5P_ARM_CORE1_CONFIGURATION); |
| 73 | |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 74 | /* |
| 75 | * here's the WFI |
| 76 | */ |
| 77 | asm(".word 0xe320f003\n" |
| 78 | : |
| 79 | : |
| 80 | : "memory", "cc"); |
| 81 | |
Will Deacon | 2f41c36 | 2011-08-09 11:29:19 +0100 | [diff] [blame] | 82 | if (pen_release == cpu_logical_map(cpu)) { |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 83 | /* |
| 84 | * OK, proper wakeup, we're done |
| 85 | */ |
| 86 | break; |
| 87 | } |
| 88 | |
| 89 | /* |
Russell King | d445026 | 2010-12-19 11:30:43 +0000 | [diff] [blame] | 90 | * Getting here, means that we have come out of WFI without |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 91 | * having been woken up - this shouldn't happen |
| 92 | * |
Russell King | d445026 | 2010-12-19 11:30:43 +0000 | [diff] [blame] | 93 | * Just note it happening - when we're woken, we can report |
| 94 | * its occurrence. |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 95 | */ |
Russell King | d445026 | 2010-12-19 11:30:43 +0000 | [diff] [blame] | 96 | (*spurious)++; |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 97 | } |
| 98 | } |
| 99 | |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 100 | /* |
| 101 | * platform-specific code to shutdown a CPU |
| 102 | * |
| 103 | * Called with IRQs disabled |
| 104 | */ |
Marc Zyngier | 06853ae | 2011-09-08 13:15:22 +0100 | [diff] [blame^] | 105 | void __ref exynos_cpu_die(unsigned int cpu) |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 106 | { |
Russell King | d445026 | 2010-12-19 11:30:43 +0000 | [diff] [blame] | 107 | int spurious = 0; |
| 108 | |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 109 | /* |
| 110 | * we're ready for shutdown now, so do it |
| 111 | */ |
| 112 | cpu_enter_lowpower(); |
Russell King | d445026 | 2010-12-19 11:30:43 +0000 | [diff] [blame] | 113 | platform_do_lowpower(cpu, &spurious); |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 114 | |
| 115 | /* |
| 116 | * bring this CPU back into the world of cache |
| 117 | * coherency, and then restore interrupts |
| 118 | */ |
| 119 | cpu_leave_lowpower(); |
Russell King | d445026 | 2010-12-19 11:30:43 +0000 | [diff] [blame] | 120 | |
| 121 | if (spurious) |
| 122 | pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious); |
Changhwan Youn | 11adcc2 | 2010-08-20 18:17:51 +0900 | [diff] [blame] | 123 | } |