ARM: socfpga: Enable SMP for socfpga

Enable SMP for the SOCFPGA platform.

Signed-off-by: Pavel Machek <pavel@denx.de>
Signed-off-by: Dinh Nguyen <dinguyen@altera.com>
Reviewed-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 116 insertions, 0 deletions

diff --git a/arch/arm/mach-socfpga/platsmp.c b/arch/arm/mach-socfpga/platsmp.c
new file mode 100644
index 00000000000..68dd1b69512
--- /dev/null
+++ b/arch/arm/mach-socfpga/platsmp.c
@@ -0,0 +1,116 @@
+/*
+ * Copyright 2010-2011 Calxeda, Inc.
+ * Copyright 2012 Pavel Machek <pavel@denx.de>
+ * Based on platsmp.c, Copyright (C) 2002 ARM Ltd.
+ * Copyright (C) 2012 Altera Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+#include <asm/cacheflush.h>
+#include <asm/hardware/gic.h>
+#include <asm/smp_scu.h>
+#include <asm/smp_plat.h>
+
+#include "core.h"
+
+extern void __iomem *sys_manager_base_addr;
+extern void __iomem *rst_manager_base_addr;
+
+static void __cpuinit socfpga_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);
+}
+
+static int __cpuinit socfpga_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	int trampoline_size = &secondary_trampoline_end - &secondary_trampoline;
+
+	memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size);
+
+	__raw_writel(virt_to_phys(secondary_startup), (sys_manager_base_addr+0x10));
+
+	flush_cache_all();
+	smp_wmb();
+	outer_clean_range(0, trampoline_size);
+
+	/* This will release CPU #1 out of reset.*/
+	__raw_writel(0, rst_manager_base_addr + 0x10);
+
+	return 0;
+}
+
+/*
+ * Initialise the CPU possible map early - this describes the CPUs
+ * which may be present or become present in the system.
+ */
+static void __init socfpga_smp_init_cpus(void)
+{
+	unsigned int i, ncores;
+
+	ncores = scu_get_core_count(socfpga_scu_base_addr);
+
+	for (i = 0; i < ncores; i++)
+		set_cpu_possible(i, true);
+
+	/* sanity check */
+	if (ncores > num_possible_cpus()) {
+		pr_warn("socfpga: no. of cores (%d) greater than configured"
+			"maximum of %d - clipping\n", ncores, num_possible_cpus());
+		ncores = num_possible_cpus();
+	}
+
+	for (i = 0; i < ncores; i++)
+		set_cpu_possible(i, true);
+
+	set_smp_cross_call(gic_raise_softirq);
+}
+
+static void __init socfpga_smp_prepare_cpus(unsigned int max_cpus)
+{
+	scu_enable(socfpga_scu_base_addr);
+}
+
+/*
+ * platform-specific code to shutdown a CPU
+ *
+ * Called with IRQs disabled
+ */
+static void socfpga_cpu_die(unsigned int cpu)
+{
+	cpu_do_idle();
+
+	/* We should have never returned from idle */
+	panic("cpu %d unexpectedly exit from shutdown\n", cpu);
+}
+
+struct smp_operations socfpga_smp_ops __initdata = {
+	.smp_init_cpus		= socfpga_smp_init_cpus,
+	.smp_prepare_cpus	= socfpga_smp_prepare_cpus,
+	.smp_secondary_init	= socfpga_secondary_init,
+	.smp_boot_secondary	= socfpga_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+	.cpu_die		= socfpga_cpu_die,
+#endif
+};