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/cdefs.h>
28 #include <sys/param.h>
29 #include <sys/systm.h>
30 #include <sys/bus.h>
31 #include <sys/kernel.h>
32 #include <sys/module.h>
33 #include <sys/sysctl.h>
34
35 #include <machine/bus.h>
36
37 #include <arm/ti/am335x/am335x_scm.h>
38 #include <arm/ti/ti_cpuid.h>
39 #include <arm/ti/ti_scm.h>
40
41 #include <dev/extres/syscon/syscon.h>
42 #include "syscon_if.h"
43
44 #define TZ_ZEROC 2731
45
46 struct am335x_scm_softc {
47 int sc_last_temp;
48 struct sysctl_oid *sc_temp_oid;
49 struct syscon *syscon;
50 };
51
52 static int
am335x_scm_temp_sysctl(SYSCTL_HANDLER_ARGS)53 am335x_scm_temp_sysctl(SYSCTL_HANDLER_ARGS)
54 {
55 device_t dev;
56 int i, temp;
57 struct am335x_scm_softc *sc;
58 uint32_t reg;
59
60 dev = (device_t)arg1;
61 sc = device_get_softc(dev);
62
63 /* Read the temperature and convert to Kelvin. */
64 for(i = 50; i > 0; i--) {
65 reg = SYSCON_READ_4(sc->syscon, SCM_BGAP_CTRL);
66 if ((reg & SCM_BGAP_EOCZ) == 0)
67 break;
68 DELAY(50);
69 }
70 if ((reg & SCM_BGAP_EOCZ) == 0) {
71 sc->sc_last_temp =
72 (reg >> SCM_BGAP_TEMP_SHIFT) & SCM_BGAP_TEMP_MASK;
73 sc->sc_last_temp *= 10;
74 }
75 temp = sc->sc_last_temp + TZ_ZEROC;
76
77 return (sysctl_handle_int(oidp, &temp, 0, req));
78 }
79
80 static void
am335x_scm_identify(driver_t * driver,device_t parent)81 am335x_scm_identify(driver_t *driver, device_t parent)
82 {
83 device_t child;
84
85 /* AM335x only. */
86 if (ti_chip() != CHIP_AM335X)
87 return;
88
89 /* Make sure we attach only once. */
90 if (device_find_child(parent, "am335x_scm", -1) != NULL)
91 return;
92
93 child = device_add_child(parent, "am335x_scm", -1);
94 if (child == NULL)
95 device_printf(parent, "cannot add ti_scm child\n");
96 }
97
98 static int
am335x_scm_probe(device_t dev)99 am335x_scm_probe(device_t dev)
100 {
101 /* Just allow the first one */
102 if (strcmp(device_get_nameunit(dev), "am335x_scm0") != 0)
103 return (ENXIO);
104
105 device_set_desc(dev, "AM335x Control Module Extension");
106
107 return (BUS_PROBE_DEFAULT);
108 }
109
110 static int
am335x_scm_attach(device_t dev)111 am335x_scm_attach(device_t dev)
112 {
113 struct am335x_scm_softc *sc;
114 struct sysctl_ctx_list *ctx;
115 struct sysctl_oid_list *tree;
116 uint32_t reg;
117 phandle_t opp_table;
118 int err;
119
120 sc = device_get_softc(dev);
121
122 /* FIXME: For now; Go and kidnap syscon from opp-table */
123 opp_table = OF_finddevice("/opp-table");
124 if (opp_table == -1) {
125 device_printf(dev, "Cant find /opp-table\n");
126 return (ENXIO);
127 }
128 if (!OF_hasprop(opp_table, "syscon")) {
129 device_printf(dev, "/opp-table missing syscon property\n");
130 return (ENXIO);
131 }
132 err = syscon_get_by_ofw_property(dev, opp_table, "syscon", &sc->syscon);
133 if (err) {
134 device_printf(dev, "Failed to get syscon\n");
135 return (ENXIO);
136 }
137
138 /* Reset the digital outputs. */
139 SYSCON_WRITE_4(sc->syscon, SCM_BGAP_CTRL, 0);
140 reg = SYSCON_READ_4(sc->syscon, SCM_BGAP_CTRL);
141 DELAY(500);
142 /* Set continuous mode. */
143 SYSCON_WRITE_4(sc->syscon, SCM_BGAP_CTRL, SCM_BGAP_CONTCONV);
144 reg = SYSCON_READ_4(sc->syscon, SCM_BGAP_CTRL);
145 DELAY(500);
146 /* Start the ADC conversion. */
147 reg = SCM_BGAP_CLRZ | SCM_BGAP_CONTCONV | SCM_BGAP_SOC;
148 SYSCON_WRITE_4(sc->syscon, SCM_BGAP_CTRL, reg);
149
150 /* Temperature sysctl. */
151 ctx = device_get_sysctl_ctx(dev);
152 tree = SYSCTL_CHILDREN(device_get_sysctl_tree(dev));
153 sc->sc_temp_oid = SYSCTL_ADD_PROC(ctx, tree, OID_AUTO,
154 "temperature", CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
155 dev, 0, am335x_scm_temp_sysctl, "IK", "Current temperature");
156
157 return (0);
158 }
159
160 static int
am335x_scm_detach(device_t dev)161 am335x_scm_detach(device_t dev)
162 {
163 struct am335x_scm_softc *sc;
164
165 sc = device_get_softc(dev);
166
167 /* Remove temperature sysctl. */
168 if (sc->sc_temp_oid != NULL)
169 sysctl_remove_oid(sc->sc_temp_oid, 1, 0);
170
171 /* Stop the bandgap ADC. */
172 SYSCON_WRITE_4(sc->syscon, SCM_BGAP_CTRL, SCM_BGAP_BGOFF);
173
174 return (0);
175 }
176
177 static device_method_t am335x_scm_methods[] = {
178 DEVMETHOD(device_identify, am335x_scm_identify),
179 DEVMETHOD(device_probe, am335x_scm_probe),
180 DEVMETHOD(device_attach, am335x_scm_attach),
181 DEVMETHOD(device_detach, am335x_scm_detach),
182
183 DEVMETHOD_END
184 };
185
186 static driver_t am335x_scm_driver = {
187 "am335x_scm",
188 am335x_scm_methods,
189 sizeof(struct am335x_scm_softc),
190 };
191
192 static devclass_t am335x_scm_devclass;
193
194 DRIVER_MODULE(am335x_scm, ti_scm, am335x_scm_driver, am335x_scm_devclass, 0, 0);
195 MODULE_VERSION(am335x_scm, 1);
196 MODULE_DEPEND(am335x_scm, ti_scm_syscon, 1, 1, 1);
197