1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (C) 2002 ARM Ltd. |
4 | * All Rights Reserved |
5 | */ |
6 | #include <linux/init.h> |
7 | #include <linux/errno.h> |
8 | #include <linux/smp.h> |
9 | #include <linux/io.h> |
10 | #include <linux/of_address.h> |
11 | #include <linux/vexpress.h> |
12 | |
13 | #include <asm/mcpm.h> |
14 | #include <asm/smp_scu.h> |
15 | #include <asm/mach/map.h> |
16 | |
17 | #include "platsmp.h" |
18 | #include "vexpress.h" |
19 | |
20 | bool __init vexpress_smp_init_ops(void) |
21 | { |
22 | #ifdef CONFIG_MCPM |
23 | int cpu; |
24 | struct device_node *cpu_node, *cci_node; |
25 | |
26 | /* |
27 | * The best way to detect a multi-cluster configuration |
28 | * is to detect if the kernel can take over CCI ports |
29 | * control. Loop over possible CPUs and check if CCI |
30 | * port control is available. |
31 | * Override the default vexpress_smp_ops if so. |
32 | */ |
33 | for_each_possible_cpu(cpu) { |
34 | bool available; |
35 | |
36 | cpu_node = of_get_cpu_node(cpu, NULL); |
37 | if (WARN(!cpu_node, "Missing cpu device node!" )) |
38 | return false; |
39 | |
40 | cci_node = of_parse_phandle(cpu_node, "cci-control-port" , 0); |
41 | available = cci_node && of_device_is_available(cci_node); |
42 | of_node_put(cci_node); |
43 | of_node_put(cpu_node); |
44 | |
45 | if (!available) |
46 | return false; |
47 | } |
48 | |
49 | mcpm_smp_set_ops(); |
50 | return true; |
51 | #else |
52 | return false; |
53 | #endif |
54 | } |
55 | |
56 | static const struct of_device_id vexpress_smp_dt_scu_match[] __initconst = { |
57 | { .compatible = "arm,cortex-a5-scu" , }, |
58 | { .compatible = "arm,cortex-a9-scu" , }, |
59 | {} |
60 | }; |
61 | |
62 | static void __init vexpress_smp_dt_prepare_cpus(unsigned int max_cpus) |
63 | { |
64 | struct device_node *scu = of_find_matching_node(NULL, |
65 | matches: vexpress_smp_dt_scu_match); |
66 | |
67 | if (scu) |
68 | scu_enable(of_iomap(node: scu, index: 0)); |
69 | |
70 | /* |
71 | * Write the address of secondary startup into the |
72 | * system-wide flags register. The boot monitor waits |
73 | * until it receives a soft interrupt, and then the |
74 | * secondary CPU branches to this address. |
75 | */ |
76 | vexpress_flags_set(__pa_symbol(versatile_secondary_startup)); |
77 | } |
78 | |
79 | #ifdef CONFIG_HOTPLUG_CPU |
80 | static void vexpress_cpu_die(unsigned int cpu) |
81 | { |
82 | versatile_immitation_cpu_die(cpu, actrl_mask: 0x40); |
83 | } |
84 | #endif |
85 | |
86 | const struct smp_operations vexpress_smp_dt_ops __initconst = { |
87 | .smp_prepare_cpus = vexpress_smp_dt_prepare_cpus, |
88 | .smp_secondary_init = versatile_secondary_init, |
89 | .smp_boot_secondary = versatile_boot_secondary, |
90 | #ifdef CONFIG_HOTPLUG_CPU |
91 | .cpu_die = vexpress_cpu_die, |
92 | #endif |
93 | }; |
94 | |