1 /* 2 * Copyright 2011 Freescale Semiconductor, Inc. 3 * Copyright 2011 Linaro Ltd. 4 * 5 * The code contained herein is licensed under the GNU General Public 6 * License. You may obtain a copy of the GNU General Public License 7 * Version 2 or later at the following locations: 8 * 9 * http://www.opensource.org/licenses/gpl-license.html 10 * http://www.gnu.org/copyleft/gpl.html 11 */ 12 13 #include <linux/errno.h> 14 #include <asm/cacheflush.h> 15 #include <asm/cp15.h> 16 #include <mach/common.h> 17 18 static inline void cpu_enter_lowpower(void) 19 { 20 unsigned int v; 21 22 flush_cache_all(); 23 asm volatile( 24 "mcr p15, 0, %1, c7, c5, 0\n" 25 " mcr p15, 0, %1, c7, c10, 4\n" 26 /* 27 * Turn off coherency 28 */ 29 " mrc p15, 0, %0, c1, c0, 1\n" 30 " bic %0, %0, %3\n" 31 " mcr p15, 0, %0, c1, c0, 1\n" 32 " mrc p15, 0, %0, c1, c0, 0\n" 33 " bic %0, %0, %2\n" 34 " mcr p15, 0, %0, c1, c0, 0\n" 35 : "=&r" (v) 36 : "r" (0), "Ir" (CR_C), "Ir" (0x40) 37 : "cc"); 38 } 39 40 /* 41 * platform-specific code to shutdown a CPU 42 * 43 * Called with IRQs disabled 44 */ 45 void imx_cpu_die(unsigned int cpu) 46 { 47 cpu_enter_lowpower(); 48 imx_enable_cpu(cpu, false); 49 50 /* spin here until hardware takes it down */ 51 while (1) 52 ; 53 } 54