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 <asm/mcpm.h> 19 #include <asm/smp.h> 20 #include <asm/smp_plat.h> 21 22 static void cpu_to_pcpu(unsigned int cpu, 23 unsigned int *pcpu, unsigned int *pcluster) 24 { 25 unsigned int mpidr; 26 27 mpidr = cpu_logical_map(cpu); 28 *pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); 29 *pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); 30 } 31 32 static int mcpm_boot_secondary(unsigned int cpu, struct task_struct *idle) 33 { 34 unsigned int pcpu, pcluster, ret; 35 extern void secondary_startup(void); 36 37 cpu_to_pcpu(cpu, &pcpu, &pcluster); 38 39 pr_debug("%s: logical CPU %d is physical CPU %d cluster %d\n", 40 __func__, cpu, pcpu, pcluster); 41 42 mcpm_set_entry_vector(pcpu, pcluster, NULL); 43 ret = mcpm_cpu_power_up(pcpu, pcluster); 44 if (ret) 45 return ret; 46 mcpm_set_entry_vector(pcpu, pcluster, secondary_startup); 47 arch_send_wakeup_ipi_mask(cpumask_of(cpu)); 48 dsb_sev(); 49 return 0; 50 } 51 52 static void mcpm_secondary_init(unsigned int cpu) 53 { 54 mcpm_cpu_powered_up(); 55 } 56 57 #ifdef CONFIG_HOTPLUG_CPU 58 59 static int mcpm_cpu_kill(unsigned int cpu) 60 { 61 unsigned int pcpu, pcluster; 62 63 cpu_to_pcpu(cpu, &pcpu, &pcluster); 64 65 return !mcpm_cpu_power_down_finish(pcpu, pcluster); 66 } 67 68 static int mcpm_cpu_disable(unsigned int cpu) 69 { 70 /* 71 * We assume all CPUs may be shut down. 72 * This would be the hook to use for eventual Secure 73 * OS migration requests as described in the PSCI spec. 74 */ 75 return 0; 76 } 77 78 static void mcpm_cpu_die(unsigned int cpu) 79 { 80 unsigned int mpidr, pcpu, pcluster; 81 mpidr = read_cpuid_mpidr(); 82 pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); 83 pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); 84 mcpm_set_entry_vector(pcpu, pcluster, NULL); 85 mcpm_cpu_power_down(); 86 } 87 88 #endif 89 90 static struct smp_operations __initdata mcpm_smp_ops = { 91 .smp_boot_secondary = mcpm_boot_secondary, 92 .smp_secondary_init = mcpm_secondary_init, 93 #ifdef CONFIG_HOTPLUG_CPU 94 .cpu_kill = mcpm_cpu_kill, 95 .cpu_disable = mcpm_cpu_disable, 96 .cpu_die = mcpm_cpu_die, 97 #endif 98 }; 99 100 void __init mcpm_smp_set_ops(void) 101 { 102 smp_set_ops(&mcpm_smp_ops); 103 } 104