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- /*
- * SMP support for R-Mobile / SH-Mobile
- *
- * Copyright (C) 2010 Magnus Damm
- *
- * Based on realview, Copyright (C) 2002 ARM Ltd, All Rights Reserved
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
- #include <linux/kernel.h>
- #include <linux/errno.h>
- #include <linux/smp.h>
- #include <linux/cpumask.h>
- #include <linux/delay.h>
- #include <mach/common.h>
- #include <asm/cacheflush.h>
- static cpumask_t dead_cpus;
- int platform_cpu_kill(unsigned int cpu)
- {
- int k;
- /* this function is running on another CPU than the offline target,
- * here we need wait for shutdown code in platform_cpu_die() to
- * finish before asking SoC-specific code to power off the CPU core.
- */
- for (k = 0; k < 1000; k++) {
- if (cpumask_test_cpu(cpu, &dead_cpus))
- return shmobile_platform_cpu_kill(cpu);
- mdelay(1);
- }
- return 0;
- }
- void platform_cpu_die(unsigned int cpu)
- {
- /* hardware shutdown code running on the CPU that is being offlined */
- flush_cache_all();
- dsb();
- /* notify platform_cpu_kill() that hardware shutdown is finished */
- cpumask_set_cpu(cpu, &dead_cpus);
- /* wait for SoC code in platform_cpu_kill() to shut off CPU core
- * power. CPU bring up starts from the reset vector.
- */
- while (1) {
- /*
- * here's the WFI
- */
- asm(".word 0xe320f003\n"
- :
- :
- : "memory", "cc");
- }
- }
- int platform_cpu_disable(unsigned int cpu)
- {
- cpumask_clear_cpu(cpu, &dead_cpus);
- /*
- * we don't allow CPU 0 to be shutdown (it is still too special
- * e.g. clock tick interrupts)
- */
- return cpu == 0 ? -EPERM : 0;
- }
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