/* * 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 <linux/mbus.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); mvebu_mbus_add_window("bootrom", 0xfff00000, SZ_1M); } 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 };