xref: /openbmc/linux/arch/sh/boards/of-generic.c (revision fa0a497b)
1 /*
2  * SH generic board support, using device tree
3  *
4  * Copyright (C) 2015-2016 Smart Energy Instruments, Inc.
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file "COPYING" in the main directory of this archive
8  * for more details.
9  */
10 
11 #include <linux/of.h>
12 #include <linux/of_platform.h>
13 #include <linux/of_fdt.h>
14 #include <linux/of_iommu.h>
15 #include <linux/clocksource.h>
16 #include <linux/irqchip.h>
17 #include <linux/clk-provider.h>
18 #include <asm/machvec.h>
19 #include <asm/rtc.h>
20 
21 #ifdef CONFIG_SMP
22 
23 static void dummy_smp_setup(void)
24 {
25 }
26 
27 static void dummy_prepare_cpus(unsigned int max_cpus)
28 {
29 }
30 
31 static void dummy_start_cpu(unsigned int cpu, unsigned long entry_point)
32 {
33 }
34 
35 static unsigned int dummy_smp_processor_id(void)
36 {
37 	return 0;
38 }
39 
40 static void dummy_send_ipi(unsigned int cpu, unsigned int message)
41 {
42 }
43 
44 static struct plat_smp_ops dummy_smp_ops = {
45 	.smp_setup		= dummy_smp_setup,
46 	.prepare_cpus		= dummy_prepare_cpus,
47 	.start_cpu		= dummy_start_cpu,
48 	.smp_processor_id	= dummy_smp_processor_id,
49 	.send_ipi		= dummy_send_ipi,
50 	.cpu_die		= native_cpu_die,
51 	.cpu_disable		= native_cpu_disable,
52 	.play_dead		= native_play_dead,
53 };
54 
55 extern const struct of_cpu_method __cpu_method_of_table[];
56 const struct of_cpu_method __cpu_method_of_table_sentinel
57 	__section(__cpu_method_of_table_end);
58 
59 static void sh_of_smp_probe(void)
60 {
61 	struct device_node *np = 0;
62 	const char *method = 0;
63 	const struct of_cpu_method *m = __cpu_method_of_table;
64 
65 	pr_info("SH generic board support: scanning for cpus\n");
66 
67 	init_cpu_possible(cpumask_of(0));
68 
69 	while ((np = of_find_node_by_type(np, "cpu"))) {
70 		const __be32 *cell = of_get_property(np, "reg", NULL);
71 		u64 id = -1;
72 		if (cell) id = of_read_number(cell, of_n_addr_cells(np));
73 		if (id < NR_CPUS) {
74 			if (!method)
75 				of_property_read_string(np, "enable-method", &method);
76 			set_cpu_possible(id, true);
77 			set_cpu_present(id, true);
78 			__cpu_number_map[id] = id;
79 			__cpu_logical_map[id] = id;
80 		}
81 	}
82 	if (!method) {
83 		np = of_find_node_by_name(NULL, "cpus");
84 		of_property_read_string(np, "enable-method", &method);
85 	}
86 
87 	pr_info("CPU enable method: %s\n", method);
88 	if (method)
89 		for (; m->method; m++)
90 			if (!strcmp(m->method, method)) {
91 				register_smp_ops(m->ops);
92 				return;
93 			}
94 
95 	register_smp_ops(&dummy_smp_ops);
96 }
97 
98 #else
99 
100 static void sh_of_smp_probe(void)
101 {
102 }
103 
104 #endif
105 
106 static void noop(void)
107 {
108 }
109 
110 static int noopi(void)
111 {
112 	return 0;
113 }
114 
115 static void __init sh_of_mem_reserve(void)
116 {
117 	early_init_fdt_reserve_self();
118 	early_init_fdt_scan_reserved_mem();
119 }
120 
121 static void __init sh_of_time_init(void)
122 {
123 	pr_info("SH generic board support: scanning for clocksource devices\n");
124 	clocksource_probe();
125 }
126 
127 static void __init sh_of_setup(char **cmdline_p)
128 {
129 	unflatten_device_tree();
130 
131 	board_time_init = sh_of_time_init;
132 
133 	sh_mv.mv_name = of_flat_dt_get_machine_name();
134 	if (!sh_mv.mv_name)
135 		sh_mv.mv_name = "Unknown SH model";
136 
137 	sh_of_smp_probe();
138 }
139 
140 static int sh_of_irq_demux(int irq)
141 {
142 	/* FIXME: eventually this should not be used at all;
143 	 * the interrupt controller should set_handle_irq(). */
144 	return irq;
145 }
146 
147 static void __init sh_of_init_irq(void)
148 {
149 	pr_info("SH generic board support: scanning for interrupt controllers\n");
150 	irqchip_init();
151 }
152 
153 static int __init sh_of_clk_init(void)
154 {
155 #ifdef CONFIG_COMMON_CLK
156 	/* Disabled pending move to COMMON_CLK framework. */
157 	pr_info("SH generic board support: scanning for clk providers\n");
158 	of_clk_init(NULL);
159 #endif
160 	return 0;
161 }
162 
163 static struct sh_machine_vector __initmv sh_of_generic_mv = {
164 	.mv_setup	= sh_of_setup,
165 	.mv_name	= "devicetree", /* replaced by DT root's model */
166 	.mv_irq_demux	= sh_of_irq_demux,
167 	.mv_init_irq	= sh_of_init_irq,
168 	.mv_clk_init	= sh_of_clk_init,
169 	.mv_mode_pins	= noopi,
170 	.mv_mem_init	= noop,
171 	.mv_mem_reserve	= sh_of_mem_reserve,
172 };
173 
174 struct sh_clk_ops;
175 
176 void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx)
177 {
178 }
179 
180 void __init plat_irq_setup(void)
181 {
182 }
183 
184 static int __init sh_of_device_init(void)
185 {
186 	pr_info("SH generic board support: populating platform devices\n");
187 	if (of_have_populated_dt()) {
188 		of_iommu_init();
189 		of_platform_populate(NULL, of_default_bus_match_table,
190 				     NULL, NULL);
191 	} else {
192 		pr_crit("Device tree not populated\n");
193 	}
194 	return 0;
195 }
196 arch_initcall_sync(sh_of_device_init);
197