1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * linux/arch/arm/mach-vexpress/mcpm_platsmp.c |
4 | * |
5 | * Created by: Nicolas Pitre, November 2012 |
6 | * Copyright: (C) 2012-2013 Linaro Limited |
7 | * |
8 | * Code to handle secondary CPU bringup and hotplug for the cluster power API. |
9 | */ |
10 | |
11 | #include <linux/init.h> |
12 | #include <linux/smp.h> |
13 | #include <linux/spinlock.h> |
14 | |
15 | #include <asm/mcpm.h> |
16 | #include <asm/smp.h> |
17 | #include <asm/smp_plat.h> |
18 | |
19 | static void cpu_to_pcpu(unsigned int cpu, |
20 | unsigned int *pcpu, unsigned int *pcluster) |
21 | { |
22 | unsigned int mpidr; |
23 | |
24 | mpidr = cpu_logical_map(cpu); |
25 | *pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); |
26 | *pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); |
27 | } |
28 | |
29 | static int mcpm_boot_secondary(unsigned int cpu, struct task_struct *idle) |
30 | { |
31 | unsigned int pcpu, pcluster, ret; |
32 | extern void secondary_startup(void); |
33 | |
34 | cpu_to_pcpu(cpu, pcpu: &pcpu, pcluster: &pcluster); |
35 | |
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 mcpm_secondary_init(unsigned int cpu) |
50 | { |
51 | mcpm_cpu_powered_up(); |
52 | } |
53 | |
54 | #ifdef CONFIG_HOTPLUG_CPU |
55 | |
56 | static int mcpm_cpu_kill(unsigned int cpu) |
57 | { |
58 | unsigned int pcpu, pcluster; |
59 | |
60 | cpu_to_pcpu(cpu, pcpu: &pcpu, pcluster: &pcluster); |
61 | |
62 | return !mcpm_wait_for_cpu_powerdown(pcpu, pcluster); |
63 | } |
64 | |
65 | static bool mcpm_cpu_can_disable(unsigned int cpu) |
66 | { |
67 | /* We assume all CPUs may be shut down. */ |
68 | return true; |
69 | } |
70 | |
71 | static void mcpm_cpu_die(unsigned int cpu) |
72 | { |
73 | unsigned int mpidr, pcpu, pcluster; |
74 | mpidr = read_cpuid_mpidr(); |
75 | pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); |
76 | pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); |
77 | mcpm_set_entry_vector(pcpu, pcluster, NULL); |
78 | mcpm_cpu_power_down(); |
79 | } |
80 | |
81 | #endif |
82 | |
83 | static const struct smp_operations mcpm_smp_ops __initconst = { |
84 | .smp_boot_secondary = mcpm_boot_secondary, |
85 | .smp_secondary_init = mcpm_secondary_init, |
86 | #ifdef CONFIG_HOTPLUG_CPU |
87 | .cpu_kill = mcpm_cpu_kill, |
88 | .cpu_can_disable = mcpm_cpu_can_disable, |
89 | .cpu_die = mcpm_cpu_die, |
90 | #endif |
91 | }; |
92 | |
93 | void __init mcpm_smp_set_ops(void) |
94 | { |
95 | smp_set_ops(&mcpm_smp_ops); |
96 | } |
97 | |