1 files changed, 147 insertions, 0 deletions
diff --git a/arch/arm/mach-msm/hotplug.c b/arch/arm/mach-msm/hotplug.c
new file mode 100644
index 000000000000..c217ded0cd3d
--- /dev/null
+++ b/arch/arm/mach-msm/hotplug.c
@@ -0,0 +1,147 @@
+/*
+ *  Copyright (C) 2002 ARM Ltd.
+ *  All Rights Reserved
+ *  Copyright (c) 2011-2014, 2016 The Linux Foundation. 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/cpu.h>
+#include <linux/notifier.h>
+#include <soc/qcom/spm.h>
+#include <soc/qcom/pm.h>
+#include <linux/irqchip/arm-gic.h>
+
+#include <asm/smp_plat.h>
+#include <asm/vfp.h>
+
+#include <soc/qcom/jtag.h>
+
+static cpumask_t cpu_dying_mask;
+
+static DEFINE_PER_CPU(unsigned int, warm_boot_flag);
+
+static inline void cpu_enter_lowpower(void)
+{
+}
+
+static inline void cpu_leave_lowpower(void)
+{
+}
+
+static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
+{
+	/* Just enter wfi for now. TODO: Properly shut off the cpu. */
+	for (;;) {
+
+		lpm_cpu_hotplug_enter(cpu);
+		if (pen_release == cpu_logical_map(cpu)) {
+			/*
+			 * OK, proper wakeup, we're done
+			 */
+			break;
+		}
+
+		/*
+		 * getting here, means that we have come out of WFI without
+		 * having been woken up - this shouldn't happen
+		 *
+		 * The trouble is, letting people know about this is not really
+		 * possible, since we are currently running incoherently, and
+		 * therefore cannot safely call printk() or anything else
+		 * Read the pending interrupts to understand why we woke up
+		 */
+#ifdef CONFIG_MSM_PM
+		gic_show_pending_irq();
+#endif
+		(*spurious)++;
+	}
+}
+
+int msm_cpu_kill(unsigned int cpu)
+{
+	int ret = 0;
+
+	if (cpumask_test_and_clear_cpu(cpu, &cpu_dying_mask))
+		ret = msm_pm_wait_cpu_shutdown(cpu);
+
+	return ret ? 0 : 1;
+}
+
+/*
+ * platform-specific code to shutdown a CPU
+ *
+ * Called with IRQs disabled
+ */
+void __ref msm_cpu_die(unsigned int cpu)
+{
+	int spurious = 0;
+
+	if (unlikely(cpu != smp_processor_id())) {
+		pr_crit("%s: running on %u, should be %u\n",
+			__func__, smp_processor_id(), cpu);
+		BUG();
+	}
+	/*
+	 * we're ready for shutdown now, so do it
+	 */
+	cpu_enter_lowpower();
+	platform_do_lowpower(cpu, &spurious);
+
+	pr_debug("CPU%u: %s: normal wakeup\n", cpu, __func__);
+	cpu_leave_lowpower();
+
+	if (spurious)
+		pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious);
+}
+
+static int hotplug_dying_callback(struct notifier_block *nfb,
+				unsigned long action, void *hcpu)
+{
+	switch (action & (~CPU_TASKS_FROZEN)) {
+	case CPU_DYING:
+		cpumask_set_cpu((unsigned long)hcpu, &cpu_dying_mask);
+		break;
+	default:
+		break;
+	}
+
+	return NOTIFY_OK;
+}
+static struct notifier_block hotplug_dying_notifier = {
+	.notifier_call = hotplug_dying_callback,
+};
+
+int msm_platform_secondary_init(unsigned int cpu)
+{
+	int ret;
+	unsigned int *warm_boot = &__get_cpu_var(warm_boot_flag);
+
+	if (!(*warm_boot)) {
+		*warm_boot = 1;
+		/*
+		 * All CPU0 boots are considered warm boots (restore needed)
+		 * since CPU0 is the system boot CPU and never cold-booted
+		 * by the kernel.
+		 */
+		if (cpu)
+			return 0;
+	}
+	msm_jtag_restore_state();
+#if defined(CONFIG_VFP) && defined (CONFIG_CPU_PM)
+	vfp_pm_resume();
+#endif
+	ret = msm_spm_set_low_power_mode(MSM_SPM_MODE_CLOCK_GATING, false);
+
+	return ret;
+}
+
+static int __init init_hotplug_dying(void)
+{
+	return register_hotcpu_notifier(&hotplug_dying_notifier);
+}
+early_initcall(init_hotplug_dying);