Michal Simek | c7c28b0 | 2013-03-20 13:56:15 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2012-2013 Xilinx |
| 3 | * |
| 4 | * based on linux/arch/arm/mach-realview/hotplug.c |
| 5 | * |
| 6 | * Copyright (C) 2002 ARM Ltd. |
| 7 | * All Rights Reserved |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU General Public License version 2 as |
| 11 | * published by the Free Software Foundation. |
| 12 | */ |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/errno.h> |
| 15 | #include <linux/smp.h> |
| 16 | |
| 17 | #include <asm/cacheflush.h> |
| 18 | #include <asm/cp15.h> |
| 19 | #include "common.h" |
| 20 | |
| 21 | static inline void zynq_cpu_enter_lowpower(void) |
| 22 | { |
| 23 | unsigned int v; |
| 24 | |
| 25 | flush_cache_all(); |
| 26 | asm volatile( |
| 27 | " mcr p15, 0, %1, c7, c5, 0\n" |
| 28 | " dsb\n" |
| 29 | /* |
| 30 | * Turn off coherency |
| 31 | */ |
| 32 | " mrc p15, 0, %0, c1, c0, 1\n" |
| 33 | " bic %0, %0, #0x40\n" |
| 34 | " mcr p15, 0, %0, c1, c0, 1\n" |
| 35 | " mrc p15, 0, %0, c1, c0, 0\n" |
| 36 | " bic %0, %0, %2\n" |
| 37 | " mcr p15, 0, %0, c1, c0, 0\n" |
| 38 | : "=&r" (v) |
| 39 | : "r" (0), "Ir" (CR_C) |
| 40 | : "cc"); |
| 41 | } |
| 42 | |
Michal Simek | c7c28b0 | 2013-03-20 13:56:15 +0100 | [diff] [blame] | 43 | /* |
| 44 | * platform-specific code to shutdown a CPU |
| 45 | * |
| 46 | * Called with IRQs disabled |
| 47 | */ |
| 48 | void zynq_platform_cpu_die(unsigned int cpu) |
| 49 | { |
Michal Simek | c7c28b0 | 2013-03-20 13:56:15 +0100 | [diff] [blame] | 50 | zynq_cpu_enter_lowpower(); |
Michal Simek | c7c28b0 | 2013-03-20 13:56:15 +0100 | [diff] [blame] | 51 | |
| 52 | /* |
Soren Brinkmann | b522877 | 2013-08-01 09:36:53 -0700 | [diff] [blame] | 53 | * there is no power-control hardware on this platform, so all |
| 54 | * we can do is put the core into WFI; this is safe as the calling |
| 55 | * code will have already disabled interrupts |
Michal Simek | c7c28b0 | 2013-03-20 13:56:15 +0100 | [diff] [blame] | 56 | */ |
Soren Brinkmann | b522877 | 2013-08-01 09:36:53 -0700 | [diff] [blame] | 57 | for (;;) |
| 58 | cpu_do_idle(); |
Michal Simek | c7c28b0 | 2013-03-20 13:56:15 +0100 | [diff] [blame] | 59 | } |