1 /*-
2 * Copyright (c) 2016 Rubicon Communications, LLC (Netgate)
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #include <sys/param.h>
28 #include <sys/systm.h>
29 #include <sys/bus.h>
30 #include <sys/kernel.h>
31 #include <sys/module.h>
32 #include <sys/sysctl.h>
33
34 #include <machine/bus.h>
35
36 #include <arm/ti/am335x/am335x_scm.h>
37 #include <arm/ti/ti_cpuid.h>
38 #include <arm/ti/ti_scm.h>
39
40 #include <dev/syscon/syscon.h>
41 #include "syscon_if.h"
42
43 #define TZ_ZEROC 2731
44
45 struct am335x_scm_softc {
46 int sc_last_temp;
47 struct sysctl_oid *sc_temp_oid;
48 struct syscon *syscon;
49 };
50
51 static int
am335x_scm_temp_sysctl(SYSCTL_HANDLER_ARGS)52 am335x_scm_temp_sysctl(SYSCTL_HANDLER_ARGS)
53 {
54 device_t dev;
55 int i, temp;
56 struct am335x_scm_softc *sc;
57 uint32_t reg;
58
59 dev = (device_t)arg1;
60 sc = device_get_softc(dev);
61
62 /* Read the temperature and convert to Kelvin. */
63 for(i = 50; i > 0; i--) {
64 reg = SYSCON_READ_4(sc->syscon, SCM_BGAP_CTRL);
65 if ((reg & SCM_BGAP_EOCZ) == 0)
66 break;
67 DELAY(50);
68 }
69 if ((reg & SCM_BGAP_EOCZ) == 0) {
70 sc->sc_last_temp =
71 (reg >> SCM_BGAP_TEMP_SHIFT) & SCM_BGAP_TEMP_MASK;
72 sc->sc_last_temp *= 10;
73 }
74 temp = sc->sc_last_temp + TZ_ZEROC;
75
76 return (sysctl_handle_int(oidp, &temp, 0, req));
77 }
78
79 static void
am335x_scm_identify(driver_t * driver,device_t parent)80 am335x_scm_identify(driver_t *driver, device_t parent)
81 {
82 device_t child;
83
84 /* AM335x only. */
85 if (ti_chip() != CHIP_AM335X)
86 return;
87
88 /* Make sure we attach only once. */
89 if (device_find_child(parent, "am335x_scm", DEVICE_UNIT_ANY) != NULL)
90 return;
91
92 child = device_add_child(parent, "am335x_scm", DEVICE_UNIT_ANY);
93 if (child == NULL)
94 device_printf(parent, "cannot add ti_scm child\n");
95 }
96
97 static int
am335x_scm_probe(device_t dev)98 am335x_scm_probe(device_t dev)
99 {
100 /* Just allow the first one */
101 if (strcmp(device_get_nameunit(dev), "am335x_scm0") != 0)
102 return (ENXIO);
103
104 device_set_desc(dev, "AM335x Control Module Extension");
105
106 return (BUS_PROBE_DEFAULT);
107 }
108
109 static int
am335x_scm_attach(device_t dev)110 am335x_scm_attach(device_t dev)
111 {
112 struct am335x_scm_softc *sc;
113 struct sysctl_ctx_list *ctx;
114 struct sysctl_oid_list *tree;
115 uint32_t reg;
116 phandle_t opp_table;
117 int err;
118
119 sc = device_get_softc(dev);
120
121 /* FIXME: For now; Go and kidnap syscon from opp-table */
122 opp_table = OF_finddevice("/opp-table");
123 if (opp_table == -1) {
124 device_printf(dev, "Cant find /opp-table\n");
125 return (ENXIO);
126 }
127 if (!OF_hasprop(opp_table, "syscon")) {
128 device_printf(dev, "/opp-table missing syscon property\n");
129 return (ENXIO);
130 }
131 err = syscon_get_by_ofw_property(dev, opp_table, "syscon", &sc->syscon);
132 if (err) {
133 device_printf(dev, "Failed to get syscon\n");
134 return (ENXIO);
135 }
136
137 /* Reset the digital outputs. */
138 SYSCON_WRITE_4(sc->syscon, SCM_BGAP_CTRL, 0);
139 reg = SYSCON_READ_4(sc->syscon, SCM_BGAP_CTRL);
140 DELAY(500);
141 /* Set continuous mode. */
142 SYSCON_WRITE_4(sc->syscon, SCM_BGAP_CTRL, SCM_BGAP_CONTCONV);
143 reg = SYSCON_READ_4(sc->syscon, SCM_BGAP_CTRL);
144 DELAY(500);
145 /* Start the ADC conversion. */
146 reg = SCM_BGAP_CLRZ | SCM_BGAP_CONTCONV | SCM_BGAP_SOC;
147 SYSCON_WRITE_4(sc->syscon, SCM_BGAP_CTRL, reg);
148
149 /* Temperature sysctl. */
150 ctx = device_get_sysctl_ctx(dev);
151 tree = SYSCTL_CHILDREN(device_get_sysctl_tree(dev));
152 sc->sc_temp_oid = SYSCTL_ADD_PROC(ctx, tree, OID_AUTO,
153 "temperature", CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
154 dev, 0, am335x_scm_temp_sysctl, "IK", "Current temperature");
155
156 return (0);
157 }
158
159 static int
am335x_scm_detach(device_t dev)160 am335x_scm_detach(device_t dev)
161 {
162 struct am335x_scm_softc *sc;
163
164 sc = device_get_softc(dev);
165
166 /* Remove temperature sysctl. */
167 if (sc->sc_temp_oid != NULL)
168 sysctl_remove_oid(sc->sc_temp_oid, 1, 0);
169
170 /* Stop the bandgap ADC. */
171 SYSCON_WRITE_4(sc->syscon, SCM_BGAP_CTRL, SCM_BGAP_BGOFF);
172
173 return (0);
174 }
175
176 static device_method_t am335x_scm_methods[] = {
177 DEVMETHOD(device_identify, am335x_scm_identify),
178 DEVMETHOD(device_probe, am335x_scm_probe),
179 DEVMETHOD(device_attach, am335x_scm_attach),
180 DEVMETHOD(device_detach, am335x_scm_detach),
181
182 DEVMETHOD_END
183 };
184
185 static driver_t am335x_scm_driver = {
186 "am335x_scm",
187 am335x_scm_methods,
188 sizeof(struct am335x_scm_softc),
189 };
190
191 DRIVER_MODULE(am335x_scm, ti_scm, am335x_scm_driver, 0, 0);
192 MODULE_VERSION(am335x_scm, 1);
193 MODULE_DEPEND(am335x_scm, ti_scm_syscon, 1, 1, 1);
194