From 849369d6c66d3054688672f97d31fceb8e8230fb Mon Sep 17 00:00:00 2001
From: root <root@artemis.panaceas.org>
Date: Fri, 25 Dec 2015 04:40:36 +0000
Subject: initial_commit

---
 arch/arm/mach-omap2/omap-smp.c | 143 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 143 insertions(+)
 create mode 100644 arch/arm/mach-omap2/omap-smp.c

(limited to 'arch/arm/mach-omap2/omap-smp.c')

diff --git a/arch/arm/mach-omap2/omap-smp.c b/arch/arm/mach-omap2/omap-smp.c
new file mode 100644
index 00000000..ecfe93c4
--- /dev/null
+++ b/arch/arm/mach-omap2/omap-smp.c
@@ -0,0 +1,143 @@
+/*
+ * OMAP4 SMP source file. It contains platform specific fucntions
+ * needed for the linux smp kernel.
+ *
+ * Copyright (C) 2009 Texas Instruments, Inc.
+ *
+ * Author:
+ *      Santosh Shilimkar <santosh.shilimkar@ti.com>
+ *
+ * Platform file needed for the OMAP4 SMP. This file is based on arm
+ * realview smp platform.
+ * * Copyright (c) 2002 ARM Limited.
+ *
+ * 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/init.h>
+#include <linux/device.h>
+#include <linux/smp.h>
+#include <linux/io.h>
+
+#include <asm/cacheflush.h>
+#include <asm/hardware/gic.h>
+#include <asm/smp_scu.h>
+#include <mach/hardware.h>
+#include <mach/omap4-common.h>
+
+/* SCU base address */
+static void __iomem *scu_base;
+
+static DEFINE_SPINLOCK(boot_lock);
+
+void __cpuinit platform_secondary_init(unsigned int cpu)
+{
+	/*
+	 * If any interrupts are already enabled for the primary
+	 * core (e.g. timer irq), then they will not have been enabled
+	 * for us: do so
+	 */
+	gic_secondary_init(0);
+
+	/*
+	 * Synchronise with the boot thread.
+	 */
+	spin_lock(&boot_lock);
+	spin_unlock(&boot_lock);
+}
+
+int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	/*
+	 * Set synchronisation state between this boot processor
+	 * and the secondary one
+	 */
+	spin_lock(&boot_lock);
+
+	/*
+	 * Update the AuxCoreBoot0 with boot state for secondary core.
+	 * omap_secondary_startup() routine will hold the secondary core till
+	 * the AuxCoreBoot1 register is updated with cpu state
+	 * A barrier is added to ensure that write buffer is drained
+	 */
+	omap_modify_auxcoreboot0(0x200, 0xfffffdff);
+	flush_cache_all();
+	smp_wmb();
+	gic_raise_softirq(cpumask_of(cpu), 1);
+
+	/*
+	 * Now the secondary core is starting up let it run its
+	 * calibrations, then wait for it to finish
+	 */
+	spin_unlock(&boot_lock);
+
+	return 0;
+}
+
+static void __init wakeup_secondary(void)
+{
+	/*
+	 * Write the address of secondary startup routine into the
+	 * AuxCoreBoot1 where ROM code will jump and start executing
+	 * on secondary core once out of WFE
+	 * A barrier is added to ensure that write buffer is drained
+	 */
+	omap_auxcoreboot_addr(virt_to_phys(omap_secondary_startup));
+	smp_wmb();
+
+	/*
+	 * Send a 'sev' to wake the secondary core from WFE.
+	 * Drain the outstanding writes to memory
+	 */
+	dsb_sev();
+	mb();
+}
+
+/*
+ * Initialise the CPU possible map early - this describes the CPUs
+ * which may be present or become present in the system.
+ */
+void __init smp_init_cpus(void)
+{
+	unsigned int i, ncores;
+
+	/* Never released */
+	scu_base = ioremap(OMAP44XX_SCU_BASE, SZ_256);
+	BUG_ON(!scu_base);
+
+	ncores = scu_get_core_count(scu_base);
+
+	/* sanity check */
+	if (ncores > NR_CPUS) {
+		printk(KERN_WARNING
+		       "OMAP4: no. of cores (%d) greater than configured "
+		       "maximum of %d - clipping\n",
+		       ncores, NR_CPUS);
+		ncores = NR_CPUS;
+	}
+
+	for (i = 0; i < ncores; i++)
+		set_cpu_possible(i, true);
+
+	set_smp_cross_call(gic_raise_softirq);
+}
+
+void __init platform_smp_prepare_cpus(unsigned int max_cpus)
+{
+	int i;
+
+	/*
+	 * Initialise the present map, which describes the set of CPUs
+	 * actually populated at the present time.
+	 */
+	for (i = 0; i < max_cpus; i++)
+		set_cpu_present(i, true);
+
+	/*
+	 * Initialise the SCU and wake up the secondary core using
+	 * wakeup_secondary().
+	 */
+	scu_enable(scu_base);
+	wakeup_secondary();
+}
-- 
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