arm: mvebu: Add SMP support for Armada XP
This enables SMP support on the Armada XP processor. It adds the
mandatory functions to support SMP such as: the SMP initialization
functions in platsmp.c, the secondary CPU entry point in headsmp.S and
the CPU hotplug initial support in hotplug.c.
Signed-off-by: Yehuda Yitschak <yehuday@marvell.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
diff --git a/arch/arm/mach-mvebu/platsmp.c b/arch/arm/mach-mvebu/platsmp.c
new file mode 100644
index 0000000..fe16aaf
--- /dev/null
+++ b/arch/arm/mach-mvebu/platsmp.c
@@ -0,0 +1,122 @@
+/*
+ * Symmetric Multi Processing (SMP) support for Armada XP
+ *
+ * Copyright (C) 2012 Marvell
+ *
+ * Lior Amsalem <alior@marvell.com>
+ * Yehuda Yitschak <yehuday@marvell.com>
+ * Gregory CLEMENT <gregory.clement@free-electrons.com>
+ * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ *
+ * The Armada XP SoC has 4 ARMv7 PJ4B CPUs running in full HW coherency
+ * This file implements the routines for preparing the SMP infrastructure
+ * and waking up the secondary CPUs
+ */
+
+#include <linux/init.h>
+#include <linux/smp.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <asm/cacheflush.h>
+#include <asm/smp_plat.h>
+#include "common.h"
+#include "armada-370-xp.h"
+#include "pmsu.h"
+#include "coherency.h"
+
+void __init set_secondary_cpus_clock(void)
+{
+ int thiscpu;
+ unsigned long rate;
+ struct clk *cpu_clk = NULL;
+ struct device_node *np = NULL;
+
+ thiscpu = smp_processor_id();
+ for_each_node_by_type(np, "cpu") {
+ int err;
+ int cpu;
+
+ err = of_property_read_u32(np, "reg", &cpu);
+ if (WARN_ON(err))
+ return;
+
+ if (cpu == thiscpu) {
+ cpu_clk = of_clk_get(np, 0);
+ break;
+ }
+ }
+ if (WARN_ON(IS_ERR(cpu_clk)))
+ return;
+ clk_prepare_enable(cpu_clk);
+ rate = clk_get_rate(cpu_clk);
+
+ /* set all the other CPU clk to the same rate than the boot CPU */
+ for_each_node_by_type(np, "cpu") {
+ int err;
+ int cpu;
+
+ err = of_property_read_u32(np, "reg", &cpu);
+ if (WARN_ON(err))
+ return;
+
+ if (cpu != thiscpu) {
+ cpu_clk = of_clk_get(np, 0);
+ clk_set_rate(cpu_clk, rate);
+ }
+ }
+}
+
+static void __cpuinit armada_xp_secondary_init(unsigned int cpu)
+{
+ armada_xp_mpic_smp_cpu_init();
+}
+
+static int __cpuinit armada_xp_boot_secondary(unsigned int cpu,
+ struct task_struct *idle)
+{
+ pr_info("Booting CPU %d\n", cpu);
+
+ armada_xp_boot_cpu(cpu, armada_xp_secondary_startup);
+
+ return 0;
+}
+
+static void __init armada_xp_smp_init_cpus(void)
+{
+ unsigned int i, ncores;
+ ncores = coherency_get_cpu_count();
+
+ /* Limit possible CPUs to defconfig */
+ if (ncores > nr_cpu_ids) {
+ pr_warn("SMP: %d CPUs physically present. Only %d configured.",
+ ncores, nr_cpu_ids);
+ pr_warn("Clipping CPU count to %d\n", nr_cpu_ids);
+ ncores = nr_cpu_ids;
+ }
+
+ for (i = 0; i < ncores; i++)
+ set_cpu_possible(i, true);
+
+ set_smp_cross_call(armada_mpic_send_doorbell);
+}
+
+void __init armada_xp_smp_prepare_cpus(unsigned int max_cpus)
+{
+ set_secondary_cpus_clock();
+ flush_cache_all();
+ set_cpu_coherent(cpu_logical_map(smp_processor_id()), 0);
+}
+
+struct smp_operations armada_xp_smp_ops __initdata = {
+ .smp_init_cpus = armada_xp_smp_init_cpus,
+ .smp_prepare_cpus = armada_xp_smp_prepare_cpus,
+ .smp_secondary_init = armada_xp_secondary_init,
+ .smp_boot_secondary = armada_xp_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_die = armada_xp_cpu_die,
+#endif
+};