/* * Copyright (C) STMicroelectronics 2009 * Copyright (C) ST-Ericsson SA 2010 * * License Terms: GNU General Public License v2 * Based on ARM realview platform * * Author: Sundar Iyer <sundar.iyer@stericsson.com> * */ #include <linux/kernel.h> #include <linux/errno.h> #include <linux/smp.h> #include <asm/cacheflush.h> #include <asm/smp_plat.h> extern volatile int pen_release; static inline void platform_do_lowpower(unsigned int cpu) { flush_cache_all(); /* we put the platform to just WFI */ for (;;) { __asm__ __volatile__("dsb\n\t" "wfi\n\t" : : : "memory"); if (pen_release == cpu_logical_map(cpu)) { /* * OK, proper wakeup, we're done */ break; } } } int platform_cpu_kill(unsigned int cpu) { return 1; } /* * platform-specific code to shutdown a CPU * * Called with IRQs disabled */ void platform_cpu_die(unsigned int cpu) { /* directly enter low power state, skipping secure registers */ platform_do_lowpower(cpu); } int platform_cpu_disable(unsigned int cpu) { /* * we don't allow CPU 0 to be shutdown (it is still too special * e.g. clock tick interrupts) */ return cpu == 0 ? -EPERM : 0; }