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
19static 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
29static 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, &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
49static void mcpm_secondary_init(unsigned int cpu)
50{
51	mcpm_cpu_powered_up();
52}
53
54#ifdef CONFIG_HOTPLUG_CPU
55
56static int mcpm_cpu_kill(unsigned int cpu)
57{
58	unsigned int pcpu, pcluster;
59
60	cpu_to_pcpu(cpu, &pcpu, &pcluster);
61
62	return !mcpm_wait_for_cpu_powerdown(pcpu, pcluster);
63}
64
65static bool mcpm_cpu_can_disable(unsigned int cpu)
66{
67	/* We assume all CPUs may be shut down. */
68	return true;
69}
70
71static 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
83static 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
93void __init mcpm_smp_set_ops(void)
94{
95	smp_set_ops(&mcpm_smp_ops);
96}
97