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Diffstat (limited to 'ANDROID_3.4.5/arch/arm/mach-shmobile/hotplug.c')
-rw-r--r--ANDROID_3.4.5/arch/arm/mach-shmobile/hotplug.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/ANDROID_3.4.5/arch/arm/mach-shmobile/hotplug.c b/ANDROID_3.4.5/arch/arm/mach-shmobile/hotplug.c
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index 00000000..828d22f3
--- /dev/null
+++ b/ANDROID_3.4.5/arch/arm/mach-shmobile/hotplug.c
@@ -0,0 +1,71 @@
+/*
+ * 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;
+}