xref: /netbsd-src/sys/arch/arm/fdt/psci_fdt.c (revision 81be3b13bd13e0892c59e7cb1db4091a29bc9fb5)
1 /* $NetBSD: psci_fdt.c,v 1.21 2021/08/06 19:38:53 jmcneill 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 1.21 2021/08/06 19:38:53 jmcneill 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/smccc.h>
44 #include <arm/arm/psci.h>
45 #include <arm/fdt/psci_fdtvar.h>
46 
47 static int	psci_fdt_match(device_t, cfdata_t, void *);
48 static void	psci_fdt_attach(device_t, device_t, void *);
49 
50 static int	psci_fdt_init(const int);
51 
52 static const struct device_compatible_entry compat_data[] = {
53 	{ .compat = "arm,psci" },
54 	{ .compat = "arm,psci-0.2" },
55 	{ .compat = "arm,psci-1.0" },
56 	DEVICE_COMPAT_EOL
57 };
58 
59 CFATTACH_DECL_NEW(psci_fdt, 0, psci_fdt_match, psci_fdt_attach, NULL, NULL);
60 
61 static void
psci_fdt_power_reset(device_t dev)62 psci_fdt_power_reset(device_t dev)
63 {
64 	delay(500000);
65 	psci_system_reset();
66 }
67 
68 static void
psci_fdt_power_poweroff(device_t dev)69 psci_fdt_power_poweroff(device_t dev)
70 {
71 	delay(500000);
72 	psci_system_off();
73 }
74 
75 static const struct fdtbus_power_controller_func psci_power_funcs = {
76 	.reset = psci_fdt_power_reset,
77 	.poweroff = psci_fdt_power_poweroff,
78 };
79 
80 static int
psci_fdt_match(device_t parent,cfdata_t cf,void * aux)81 psci_fdt_match(device_t parent, cfdata_t cf, void *aux)
82 {
83 	struct fdt_attach_args * const faa = aux;
84 
85 	return of_compatible_match(faa->faa_phandle, compat_data);
86 }
87 
88 static void
psci_fdt_attach(device_t parent,device_t self,void * aux)89 psci_fdt_attach(device_t parent, device_t self, void *aux)
90 {
91 	struct fdt_attach_args * const faa = aux;
92 	const int phandle = faa->faa_phandle;
93 
94 	psci_fdt_init(phandle);
95 
96 	const uint32_t ver = psci_version();
97 	const u_int ver_maj = __SHIFTOUT(ver, PSCI_VERSION_MAJOR);
98 	const u_int ver_min = __SHIFTOUT(ver, PSCI_VERSION_MINOR);
99 
100 	aprint_naive("\n");
101 	aprint_normal(": PSCI %u.%u\n", ver_maj, ver_min);
102 
103 	fdtbus_register_power_controller(self, phandle,
104 	    &psci_power_funcs);
105 }
106 
107 static int
psci_fdt_init(const int phandle)108 psci_fdt_init(const int phandle)
109 {
110 	const char *method, *psciver;
111 	uint32_t val;
112 
113 	method = fdtbus_get_string(phandle, "method");
114 	psciver = fdtbus_get_string(phandle, "compatible");
115 	if (method == NULL || psciver == NULL) {
116 		aprint_error("PSCI: missing required property on /psci\n");
117 		return EINVAL;
118 	}
119 
120 	if (strcmp(method, "smc") == 0)
121 		psci_init(psci_call_smc);
122 	else if (strcmp(method, "hvc") == 0)
123 		psci_init(psci_call_hvc);
124 	else {
125 		aprint_error("PSCI: unsupported method '%s'\n", method);
126 		return EINVAL;
127 	}
128 
129 	/*
130 	 * If the first compatible string is "arm,psci" then we
131 	 * are dealing with PSCI 0.1
132 	 */
133 	if (strcmp(psciver, "arm,psci") == 0) {
134 		psci_clearfunc();
135 		if (of_getprop_uint32(phandle, "cpu_on", &val) == 0)
136 			psci_setfunc(PSCI_FUNC_CPU_ON, val);
137 	}
138 
139 	smccc_probe();
140 
141 	return 0;
142 }
143 
144 int
psci_fdt_preinit(void)145 psci_fdt_preinit(void)
146 {
147 	const int phandle = OF_finddevice("/psci");
148 	if (phandle == -1) {
149 		aprint_error("PSCI: no /psci node found\n");
150 		return ENODEV;
151 	}
152 
153 	return psci_fdt_init(phandle);
154 }
155 
156 void
psci_fdt_reset(void)157 psci_fdt_reset(void)
158 {
159 	if (psci_fdt_preinit() != 0) {
160 		aprint_error("PSCI: reset failed\n");
161 		return;
162 	}
163 
164 	psci_system_reset();
165 }
166