1 /* 2 * This program is free software; you can redistribute it and/or modify 3 * it under the terms of the GNU General Public License version 2 as 4 * published by the Free Software Foundation. 5 * 6 * This program is distributed in the hope that it will be useful, 7 * but WITHOUT ANY WARRANTY; without even the implied warranty of 8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 9 * GNU General Public License for more details. 10 * 11 * Copyright (C) 2012 ARM Limited 12 * 13 * Author: Will Deacon <will.deacon@arm.com> 14 */ 15 16 #include <linux/init.h> 17 #include <linux/irqchip/arm-gic.h> 18 #include <linux/smp.h> 19 #include <linux/of.h> 20 21 #include <asm/psci.h> 22 #include <asm/smp_plat.h> 23 24 /* 25 * psci_smp assumes that the following is true about PSCI: 26 * 27 * cpu_suspend Suspend the execution on a CPU 28 * @state we don't currently describe affinity levels, so just pass 0. 29 * @entry_point the first instruction to be executed on return 30 * returns 0 success, < 0 on failure 31 * 32 * cpu_off Power down a CPU 33 * @state we don't currently describe affinity levels, so just pass 0. 34 * no return on successful call 35 * 36 * cpu_on Power up a CPU 37 * @cpuid cpuid of target CPU, as from MPIDR 38 * @entry_point the first instruction to be executed on return 39 * returns 0 success, < 0 on failure 40 * 41 * migrate Migrate the context to a different CPU 42 * @cpuid cpuid of target CPU, as from MPIDR 43 * returns 0 success, < 0 on failure 44 * 45 */ 46 47 extern void secondary_startup(void); 48 49 static int psci_boot_secondary(unsigned int cpu, struct task_struct *idle) 50 { 51 if (psci_ops.cpu_on) 52 return psci_ops.cpu_on(cpu_logical_map(cpu), 53 __pa(secondary_startup)); 54 return -ENODEV; 55 } 56 57 #ifdef CONFIG_HOTPLUG_CPU 58 void __ref psci_cpu_die(unsigned int cpu) 59 { 60 const struct psci_power_state ps = { 61 .type = PSCI_POWER_STATE_TYPE_POWER_DOWN, 62 }; 63 64 if (psci_ops.cpu_off) 65 psci_ops.cpu_off(ps); 66 67 /* We should never return */ 68 panic("psci: cpu %d failed to shutdown\n", cpu); 69 } 70 #endif 71 72 bool __init psci_smp_available(void) 73 { 74 /* is cpu_on available at least? */ 75 return (psci_ops.cpu_on != NULL); 76 } 77 78 struct smp_operations __initdata psci_smp_ops = { 79 .smp_boot_secondary = psci_boot_secondary, 80 #ifdef CONFIG_HOTPLUG_CPU 81 .cpu_die = psci_cpu_die, 82 #endif 83 }; 84