1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright 2010-2011 Calxeda, Inc.
4 * Copyright 2012 Pavel Machek <pavel@denx.de>
5 * Based on platsmp.c, Copyright (C) 2002 ARM Ltd.
6 * Copyright (C) 2012 Altera Corporation
7 */
8 #include <linux/delay.h>
9 #include <linux/init.h>
10 #include <linux/smp.h>
11 #include <linux/io.h>
12 #include <linux/of.h>
13 #include <linux/of_address.h>
14
15 #include <asm/cacheflush.h>
16 #include <asm/smp_scu.h>
17 #include <asm/smp_plat.h>
18
19 #include "core.h"
20
21 static int socfpga_boot_secondary(unsigned int cpu, struct task_struct *idle)
22 {
23 int trampoline_size = secondary_trampoline_end - secondary_trampoline;
24
25 if (socfpga_cpu1start_addr) {
26 /* This will put CPU #1 into reset. */
27 writel(RSTMGR_MPUMODRST_CPU1,
28 rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST);
29
30 memcpy(phys_to_virt(0), secondary_trampoline, trampoline_size);
31
32 writel(__pa_symbol(secondary_startup),
33 sys_manager_base_addr + (socfpga_cpu1start_addr & 0x000000ff));
34
35 flush_cache_all();
36 smp_wmb();
37 outer_clean_range(0, trampoline_size);
38
39 /* This will release CPU #1 out of reset. */
40 writel(0, rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST);
41 }
42
43 return 0;
44 }
45
46 static int socfpga_a10_boot_secondary(unsigned int cpu, struct task_struct *idle)
47 {
48 int trampoline_size = secondary_trampoline_end - secondary_trampoline;
49
50 if (socfpga_cpu1start_addr) {
51 writel(RSTMGR_MPUMODRST_CPU1, rst_manager_base_addr +
52 SOCFPGA_A10_RSTMGR_MODMPURST);
53 memcpy(phys_to_virt(0), secondary_trampoline, trampoline_size);
54
55 writel(__pa_symbol(secondary_startup),
56 sys_manager_base_addr + (socfpga_cpu1start_addr & 0x00000fff));
57
58 flush_cache_all();
59 smp_wmb();
60 outer_clean_range(0, trampoline_size);
61
62 /* This will release CPU #1 out of reset. */
63 writel(0, rst_manager_base_addr + SOCFPGA_A10_RSTMGR_MODMPURST);
64 }
65
66 return 0;
67 }
68
69 static void __init socfpga_smp_prepare_cpus(unsigned int max_cpus)
70 {
71 struct device_node *np;
72 void __iomem *socfpga_scu_base_addr;
73
74 np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu");
75 if (!np) {
76 pr_err("%s: missing scu\n", __func__);
77 return;
78 }
79
80 socfpga_scu_base_addr = of_iomap(np, 0);
81 if (!socfpga_scu_base_addr)
82 return;
83 scu_enable(socfpga_scu_base_addr);
84 }
85
86 #ifdef CONFIG_HOTPLUG_CPU
87 /*
88 * platform-specific code to shutdown a CPU
89 *
90 * Called with IRQs disabled
91 */
92 static void socfpga_cpu_die(unsigned int cpu)
93 {
94 /* Do WFI. If we wake up early, go back into WFI */
95 while (1)
96 cpu_do_idle();
97 }
98
99 /*
100 * We need a dummy function so that platform_can_cpu_hotplug() knows
101 * we support CPU hotplug. However, the function does not need to do
102 * anything, because CPUs going offline just do WFI. We could reset
103 * the CPUs but it would increase power consumption.
104 */
105 static int socfpga_cpu_kill(unsigned int cpu)
106 {
107 return 1;
108 }
109 #endif
110
111 static const struct smp_operations socfpga_smp_ops __initconst = {
112 .smp_prepare_cpus = socfpga_smp_prepare_cpus,
113 .smp_boot_secondary = socfpga_boot_secondary,
114 #ifdef CONFIG_HOTPLUG_CPU
115 .cpu_die = socfpga_cpu_die,
116 .cpu_kill = socfpga_cpu_kill,
117 #endif
118 };
119
120 static const struct smp_operations socfpga_a10_smp_ops __initconst = {
121 .smp_prepare_cpus = socfpga_smp_prepare_cpus,
122 .smp_boot_secondary = socfpga_a10_boot_secondary,
123 #ifdef CONFIG_HOTPLUG_CPU
124 .cpu_die = socfpga_cpu_die,
125 .cpu_kill = socfpga_cpu_kill,
126 #endif
127 };
128
129 CPU_METHOD_OF_DECLARE(socfpga_smp, "altr,socfpga-smp", &socfpga_smp_ops);
130 CPU_METHOD_OF_DECLARE(socfpga_a10_smp, "altr,socfpga-a10-smp", &socfpga_a10_smp_ops);
131
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