xref: /netbsd-src/sys/arch/arm/fdt/psci_fdt.c (revision 6e54367a22fbc89a1139d033e95bec0c0cf0975b)
1 /* $NetBSD: psci_fdt.c,v 1.20 2021/01/27 03:10:19 thorpej Exp $ */
2 
3 /*-
4  * Copyright (c) 2017 Jared McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include "opt_multiprocessor.h"
30 
31 #include <sys/cdefs.h>
32 __KERNEL_RCSID(0, "$NetBSD: psci_fdt.c,v 1.20 2021/01/27 03:10:19 thorpej Exp $");
33 
34 #include <sys/param.h>
35 #include <sys/atomic.h>
36 #include <sys/bus.h>
37 #include <sys/device.h>
38 #include <sys/kernel.h>
39 #include <sys/systm.h>
40 
41 #include <dev/fdt/fdtvar.h>
42 
43 #include <arm/arm/psci.h>
44 #include <arm/fdt/psci_fdtvar.h>
45 
46 static int	psci_fdt_match(device_t, cfdata_t, void *);
47 static void	psci_fdt_attach(device_t, device_t, void *);
48 
49 static int	psci_fdt_init(const int);
50 
51 static const struct device_compatible_entry compat_data[] = {
52 	{ .compat = "arm,psci" },
53 	{ .compat = "arm,psci-0.2" },
54 	{ .compat = "arm,psci-1.0" },
55 	DEVICE_COMPAT_EOL
56 };
57 
58 CFATTACH_DECL_NEW(psci_fdt, 0, psci_fdt_match, psci_fdt_attach, NULL, NULL);
59 
60 static void
61 psci_fdt_power_reset(device_t dev)
62 {
63 	delay(500000);
64 	psci_system_reset();
65 }
66 
67 static void
68 psci_fdt_power_poweroff(device_t dev)
69 {
70 	delay(500000);
71 	psci_system_off();
72 }
73 
74 static const struct fdtbus_power_controller_func psci_power_funcs = {
75 	.reset = psci_fdt_power_reset,
76 	.poweroff = psci_fdt_power_poweroff,
77 };
78 
79 static int
80 psci_fdt_match(device_t parent, cfdata_t cf, void *aux)
81 {
82 	struct fdt_attach_args * const faa = aux;
83 
84 	return of_compatible_match(faa->faa_phandle, compat_data);
85 }
86 
87 static void
88 psci_fdt_attach(device_t parent, device_t self, void *aux)
89 {
90 	struct fdt_attach_args * const faa = aux;
91 	const int phandle = faa->faa_phandle;
92 
93 	psci_fdt_init(phandle);
94 
95 	const uint32_t ver = psci_version();
96 	const u_int ver_maj = __SHIFTOUT(ver, PSCI_VERSION_MAJOR);
97 	const u_int ver_min = __SHIFTOUT(ver, PSCI_VERSION_MINOR);
98 
99 	aprint_naive("\n");
100 	aprint_normal(": PSCI %u.%u\n", ver_maj, ver_min);
101 
102 	fdtbus_register_power_controller(self, phandle,
103 	    &psci_power_funcs);
104 }
105 
106 static int
107 psci_fdt_init(const int phandle)
108 {
109 	const char *method, *psciver;
110 	uint32_t val;
111 
112 	method = fdtbus_get_string(phandle, "method");
113 	psciver = fdtbus_get_string(phandle, "compatible");
114 	if (method == NULL || psciver == NULL) {
115 		aprint_error("PSCI: missing required property on /psci\n");
116 		return EINVAL;
117 	}
118 
119 	if (strcmp(method, "smc") == 0)
120 		psci_init(psci_call_smc);
121 	else if (strcmp(method, "hvc") == 0)
122 		psci_init(psci_call_hvc);
123 	else {
124 		aprint_error("PSCI: unsupported method '%s'\n", method);
125 		return EINVAL;
126 	}
127 
128 	/*
129 	 * If the first compatible string is "arm,psci" then we
130 	 * are dealing with PSCI 0.1
131 	 */
132 	if (strcmp(psciver, "arm,psci") == 0) {
133 		psci_clearfunc();
134 		if (of_getprop_uint32(phandle, "cpu_on", &val) == 0)
135 			psci_setfunc(PSCI_FUNC_CPU_ON, val);
136 	}
137 
138 	return 0;
139 }
140 
141 int
142 psci_fdt_preinit(void)
143 {
144 	const int phandle = OF_finddevice("/psci");
145 	if (phandle == -1) {
146 		aprint_error("PSCI: no /psci node found\n");
147 		return ENODEV;
148 	}
149 
150 	return psci_fdt_init(phandle);
151 }
152 
153 void
154 psci_fdt_reset(void)
155 {
156 	if (psci_fdt_preinit() != 0) {
157 		aprint_error("PSCI: reset failed\n");
158 		return;
159 	}
160 
161 	psci_system_reset();
162 }
163