arm/imx6q: add smp and cpu hotplug support

It adds smp and cpu hotplug support for imx6q.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

arch/arm/mach-imx/platsmp.c

@@ -0,0 +1,85 @@
+/*
+ * Copyright 2011 Freescale Semiconductor, Inc.
+ * Copyright 2011 Linaro Ltd.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <asm/page.h>
+#include <asm/smp_scu.h>
+#include <asm/hardware/gic.h>
+#include <asm/mach/map.h>
+#include <mach/common.h>
+#include <mach/hardware.h>
+
+static void __iomem *scu_base;
+
+static struct map_desc scu_io_desc __initdata = {
+	/* .virtual and .pfn are run-time assigned */
+	.length		= SZ_4K,
+	.type		= MT_DEVICE,
+};
+
+void __init imx_scu_map_io(void)
+{
+	unsigned long base;
+
+	/* Get SCU base */
+	asm("mrc p15, 4, %0, c15, c0, 0" : "=r" (base));
+
+	scu_io_desc.virtual = IMX_IO_P2V(base);
+	scu_io_desc.pfn = __phys_to_pfn(base);
+	iotable_init(&scu_io_desc, 1);
+
+	scu_base = IMX_IO_ADDRESS(base);
+}
+
+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);
+}
+
+int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	imx_set_cpu_jump(cpu, v7_secondary_startup);
+	imx_enable_cpu(cpu, true);
+	return 0;
+}
+
+/*
+ * 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)
+{
+	int i, ncores;
+
+	ncores = scu_get_core_count(scu_base);
+
+	for (i = 0; i < ncores; i++)
+		set_cpu_possible(i, true);
+
+	set_smp_cross_call(gic_raise_softirq);
+}
+
+void imx_smp_prepare(void)
+{
+	scu_enable(scu_base);
+}
+
+void __init platform_smp_prepare_cpus(unsigned int max_cpus)
+{
+	imx_smp_prepare();
+}