1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright: (C) 2018 Socionext Inc.
4 * Copyright: (C) 2015 Linaro Ltd.
5 */
6
7#include <linux/cpu_pm.h>
8#include <linux/irqchip/arm-gic.h>
9#include <linux/of_address.h>
10#include <linux/suspend.h>
11
12#include <asm/cacheflush.h>
13#include <asm/cp15.h>
14#include <asm/idmap.h>
15#include <asm/smp_plat.h>
16#include <asm/suspend.h>
17
18#define M10V_MAX_CPU 4
19#define KERNEL_UNBOOT_FLAG 0x12345678
20
21static void __iomem *m10v_smp_base;
22
23static int m10v_boot_secondary(unsigned int l_cpu, struct task_struct *idle)
24{
25 unsigned int mpidr, cpu, cluster;
26
27 if (!m10v_smp_base)
28 return -ENXIO;
29
30 mpidr = cpu_logical_map(l_cpu);
31 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
32 cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
33
34 if (cpu >= M10V_MAX_CPU)
35 return -EINVAL;
36
37 pr_info("%s: cpu %u l_cpu %u cluster %u\n",
38 __func__, cpu, l_cpu, cluster);
39
40 writel(__pa_symbol(secondary_startup), m10v_smp_base + cpu * 4);
41 arch_send_wakeup_ipi_mask(cpumask_of(l_cpu));
42
43 return 0;
44}
45
46static void m10v_smp_init(unsigned int max_cpus)
47{
48 unsigned int mpidr, cpu, cluster;
49 struct device_node *np;
50
51 np = of_find_compatible_node(NULL, NULL, compat: "socionext,milbeaut-smp-sram");
52 if (!np)
53 return;
54
55 m10v_smp_base = of_iomap(node: np, index: 0);
56 if (!m10v_smp_base)
57 return;
58
59 mpidr = read_cpuid_mpidr();
60 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
61 cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
62 pr_info("MCPM boot on cpu_%u cluster_%u\n", cpu, cluster);
63
64 for (cpu = 0; cpu < M10V_MAX_CPU; cpu++)
65 writel(KERNEL_UNBOOT_FLAG, addr: m10v_smp_base + cpu * 4);
66}
67
68#ifdef CONFIG_HOTPLUG_CPU
69static void m10v_cpu_die(unsigned int l_cpu)
70{
71 gic_cpu_if_down(gic_nr: 0);
72 v7_exit_coherency_flush(louis);
73 wfi();
74}
75
76static int m10v_cpu_kill(unsigned int l_cpu)
77{
78 unsigned int mpidr, cpu;
79
80 mpidr = cpu_logical_map(l_cpu);
81 cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
82
83 writel(KERNEL_UNBOOT_FLAG, addr: m10v_smp_base + cpu * 4);
84
85 return 1;
86}
87#endif
88
89static struct smp_operations m10v_smp_ops __initdata = {
90 .smp_prepare_cpus = m10v_smp_init,
91 .smp_boot_secondary = m10v_boot_secondary,
92#ifdef CONFIG_HOTPLUG_CPU
93 .cpu_die = m10v_cpu_die,
94 .cpu_kill = m10v_cpu_kill,
95#endif
96};
97CPU_METHOD_OF_DECLARE(m10v_smp, "socionext,milbeaut-m10v-smp", &m10v_smp_ops);
98
99static int m10v_pm_valid(suspend_state_t state)
100{
101 return (state == PM_SUSPEND_STANDBY) || (state == PM_SUSPEND_MEM);
102}
103
104typedef void (*phys_reset_t)(unsigned long);
105static phys_reset_t phys_reset;
106
107static int m10v_die(unsigned long arg)
108{
109 setup_mm_for_reboot();
110 asm("wfi");
111 /* Boot just like a secondary */
112 phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(address: cpu_reset);
113 phys_reset(virt_to_phys(address: cpu_resume));
114
115 return 0;
116}
117
118static int m10v_pm_enter(suspend_state_t state)
119{
120 switch (state) {
121 case PM_SUSPEND_STANDBY:
122 asm("wfi");
123 break;
124 case PM_SUSPEND_MEM:
125 cpu_pm_enter();
126 cpu_suspend(0, m10v_die);
127 cpu_pm_exit();
128 break;
129 }
130 return 0;
131}
132
133static const struct platform_suspend_ops m10v_pm_ops = {
134 .valid = m10v_pm_valid,
135 .enter = m10v_pm_enter,
136};
137
138struct clk *m10v_clclk_register(struct device *cpu_dev);
139
140static int __init m10v_pm_init(void)
141{
142 if (of_machine_is_compatible(compat: "socionext,milbeaut-evb"))
143 suspend_set_ops(ops: &m10v_pm_ops);
144
145 return 0;
146}
147late_initcall(m10v_pm_init);
148

source code of linux/arch/arm/mach-milbeaut/platsmp.c