1 /* 2 * linux/arch/arm/mach-vexpress/mcpm_platsmp.c 3 * 4 * Created by: Nicolas Pitre, November 2012 5 * Copyright: (C) 2012-2013 Linaro Limited 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * Code to handle secondary CPU bringup and hotplug for the cluster power API. 12 */ 13 14 #include <linux/init.h> 15 #include <linux/smp.h> 16 #include <linux/spinlock.h> 17 18 #include <linux/irqchip/arm-gic.h> 19 20 #include <asm/mcpm.h> 21 #include <asm/smp.h> 22 #include <asm/smp_plat.h> 23 24 static void __init simple_smp_init_cpus(void) 25 { 26 } 27 28 static int __cpuinit mcpm_boot_secondary(unsigned int cpu, struct task_struct *idle) 29 { 30 unsigned int mpidr, pcpu, pcluster, ret; 31 extern void secondary_startup(void); 32 33 mpidr = cpu_logical_map(cpu); 34 pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); 35 pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); 36 pr_debug("%s: logical CPU %d is physical CPU %d cluster %d\n", 37 __func__, cpu, pcpu, pcluster); 38 39 mcpm_set_entry_vector(pcpu, pcluster, NULL); 40 ret = mcpm_cpu_power_up(pcpu, pcluster); 41 if (ret) 42 return ret; 43 mcpm_set_entry_vector(pcpu, pcluster, secondary_startup); 44 arch_send_wakeup_ipi_mask(cpumask_of(cpu)); 45 dsb_sev(); 46 return 0; 47 } 48 49 static void __cpuinit mcpm_secondary_init(unsigned int cpu) 50 { 51 mcpm_cpu_powered_up(); 52 gic_secondary_init(0); 53 } 54 55 #ifdef CONFIG_HOTPLUG_CPU 56 57 static int mcpm_cpu_disable(unsigned int cpu) 58 { 59 /* 60 * We assume all CPUs may be shut down. 61 * This would be the hook to use for eventual Secure 62 * OS migration requests as described in the PSCI spec. 63 */ 64 return 0; 65 } 66 67 static void mcpm_cpu_die(unsigned int cpu) 68 { 69 unsigned int mpidr, pcpu, pcluster; 70 mpidr = read_cpuid_mpidr(); 71 pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); 72 pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); 73 mcpm_set_entry_vector(pcpu, pcluster, NULL); 74 mcpm_cpu_power_down(); 75 } 76 77 #endif 78 79 static struct smp_operations __initdata mcpm_smp_ops = { 80 .smp_init_cpus = simple_smp_init_cpus, 81 .smp_boot_secondary = mcpm_boot_secondary, 82 .smp_secondary_init = mcpm_secondary_init, 83 #ifdef CONFIG_HOTPLUG_CPU 84 .cpu_disable = mcpm_cpu_disable, 85 .cpu_die = mcpm_cpu_die, 86 #endif 87 }; 88 89 void __init mcpm_smp_set_ops(void) 90 { 91 smp_set_ops(&mcpm_smp_ops); 92 } 93