xref: /openbmc/linux/arch/sh/boards/of-generic.c (revision b4e18b29)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * SH generic board support, using device tree
4  *
5  * Copyright (C) 2015-2016 Smart Energy Instruments, Inc.
6  */
7 
8 #include <linux/of.h>
9 #include <linux/of_clk.h>
10 #include <linux/of_fdt.h>
11 #include <linux/clocksource.h>
12 #include <linux/irqchip.h>
13 #include <asm/machvec.h>
14 #include <asm/rtc.h>
15 
16 #ifdef CONFIG_SMP
17 
18 static void dummy_smp_setup(void)
19 {
20 }
21 
22 static void dummy_prepare_cpus(unsigned int max_cpus)
23 {
24 }
25 
26 static void dummy_start_cpu(unsigned int cpu, unsigned long entry_point)
27 {
28 }
29 
30 static unsigned int dummy_smp_processor_id(void)
31 {
32 	return 0;
33 }
34 
35 static void dummy_send_ipi(unsigned int cpu, unsigned int message)
36 {
37 }
38 
39 static struct plat_smp_ops dummy_smp_ops = {
40 	.smp_setup		= dummy_smp_setup,
41 	.prepare_cpus		= dummy_prepare_cpus,
42 	.start_cpu		= dummy_start_cpu,
43 	.smp_processor_id	= dummy_smp_processor_id,
44 	.send_ipi		= dummy_send_ipi,
45 	.cpu_die		= native_cpu_die,
46 	.cpu_disable		= native_cpu_disable,
47 	.play_dead		= native_play_dead,
48 };
49 
50 extern const struct of_cpu_method __cpu_method_of_table[];
51 const struct of_cpu_method __cpu_method_of_table_sentinel
52 	__section("__cpu_method_of_table_end");
53 
54 static void sh_of_smp_probe(void)
55 {
56 	struct device_node *np;
57 	const char *method = NULL;
58 	const struct of_cpu_method *m = __cpu_method_of_table;
59 
60 	pr_info("SH generic board support: scanning for cpus\n");
61 
62 	init_cpu_possible(cpumask_of(0));
63 
64 	for_each_of_cpu_node(np) {
65 		const __be32 *cell = of_get_property(np, "reg", NULL);
66 		u64 id = -1;
67 		if (cell) id = of_read_number(cell, of_n_addr_cells(np));
68 		if (id < NR_CPUS) {
69 			if (!method)
70 				of_property_read_string(np, "enable-method", &method);
71 			set_cpu_possible(id, true);
72 			set_cpu_present(id, true);
73 			__cpu_number_map[id] = id;
74 			__cpu_logical_map[id] = id;
75 		}
76 	}
77 	if (!method) {
78 		np = of_find_node_by_name(NULL, "cpus");
79 		of_property_read_string(np, "enable-method", &method);
80 		of_node_put(np);
81 	}
82 
83 	pr_info("CPU enable method: %s\n", method);
84 	if (method)
85 		for (; m->method; m++)
86 			if (!strcmp(m->method, method)) {
87 				register_smp_ops(m->ops);
88 				return;
89 			}
90 
91 	register_smp_ops(&dummy_smp_ops);
92 }
93 
94 #else
95 
96 static void sh_of_smp_probe(void)
97 {
98 }
99 
100 #endif
101 
102 static void noop(void)
103 {
104 }
105 
106 static int noopi(void)
107 {
108 	return 0;
109 }
110 
111 static void __init sh_of_mem_reserve(void)
112 {
113 	early_init_fdt_reserve_self();
114 	early_init_fdt_scan_reserved_mem();
115 }
116 
117 static void __init sh_of_setup(char **cmdline_p)
118 {
119 	struct device_node *root;
120 
121 	sh_mv.mv_name = "Unknown SH model";
122 	root = of_find_node_by_path("/");
123 	if (root) {
124 		of_property_read_string(root, "model", &sh_mv.mv_name);
125 		of_node_put(root);
126 	}
127 
128 	sh_of_smp_probe();
129 }
130 
131 static int sh_of_irq_demux(int irq)
132 {
133 	/* FIXME: eventually this should not be used at all;
134 	 * the interrupt controller should set_handle_irq(). */
135 	return irq;
136 }
137 
138 static void __init sh_of_init_irq(void)
139 {
140 	pr_info("SH generic board support: scanning for interrupt controllers\n");
141 	irqchip_init();
142 }
143 
144 static int __init sh_of_clk_init(void)
145 {
146 #ifdef CONFIG_COMMON_CLK
147 	/* Disabled pending move to COMMON_CLK framework. */
148 	pr_info("SH generic board support: scanning for clk providers\n");
149 	of_clk_init(NULL);
150 #endif
151 	return 0;
152 }
153 
154 static struct sh_machine_vector __initmv sh_of_generic_mv = {
155 	.mv_setup	= sh_of_setup,
156 	.mv_name	= "devicetree", /* replaced by DT root's model */
157 	.mv_irq_demux	= sh_of_irq_demux,
158 	.mv_init_irq	= sh_of_init_irq,
159 	.mv_clk_init	= sh_of_clk_init,
160 	.mv_mode_pins	= noopi,
161 	.mv_mem_init	= noop,
162 	.mv_mem_reserve	= sh_of_mem_reserve,
163 };
164 
165 struct sh_clk_ops;
166 
167 void __init __weak arch_init_clk_ops(struct sh_clk_ops **ops, int idx)
168 {
169 }
170 
171 void __init __weak plat_irq_setup(void)
172 {
173 }
174