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__FBSDID("$FreeBSD$");
29
30#include <sys/param.h>
31#include <sys/systm.h>
32#include <sys/bus.h>
33#include <sys/kernel.h>
34#include <sys/module.h>
35#include <sys/sysctl.h>
36
37#include <machine/bus.h>
38
39#include <arm/ti/am335x/am335x_scm.h>
40#include <arm/ti/ti_cpuid.h>
41#include <arm/ti/ti_scm.h>
42
43#include <dev/extres/syscon/syscon.h>
44#include "syscon_if.h"
45
46#define	TZ_ZEROC	2731
47
48struct am335x_scm_softc {
49	int			sc_last_temp;
50	struct sysctl_oid	*sc_temp_oid;
51	struct syscon		*syscon;
52};
53
54static int
55am335x_scm_temp_sysctl(SYSCTL_HANDLER_ARGS)
56{
57	device_t dev;
58	int i, temp;
59	struct am335x_scm_softc *sc;
60	uint32_t reg;
61
62	dev = (device_t)arg1;
63	sc = device_get_softc(dev);
64
65	/* Read the temperature and convert to Kelvin. */
66	for(i = 50; i > 0; i--) {
67		reg = SYSCON_READ_4(sc->syscon, SCM_BGAP_CTRL);
68		if ((reg & SCM_BGAP_EOCZ) == 0)
69			break;
70		DELAY(50);
71	}
72	if ((reg & SCM_BGAP_EOCZ) == 0) {
73		sc->sc_last_temp =
74		    (reg >> SCM_BGAP_TEMP_SHIFT) & SCM_BGAP_TEMP_MASK;
75		sc->sc_last_temp *= 10;
76	}
77	temp = sc->sc_last_temp + TZ_ZEROC;
78
79	return (sysctl_handle_int(oidp, &temp, 0, req));
80}
81
82static void
83am335x_scm_identify(driver_t *driver, device_t parent)
84{
85	device_t child;
86
87	/* AM335x only. */
88	if (ti_chip() != CHIP_AM335X)
89		return;
90
91	/* Make sure we attach only once. */
92	if (device_find_child(parent, "am335x_scm", -1) != NULL)
93		return;
94
95	child = device_add_child(parent, "am335x_scm", -1);
96	if (child == NULL)
97		device_printf(parent, "cannot add ti_scm child\n");
98}
99
100static int
101am335x_scm_probe(device_t dev)
102{
103	/* Just allow the first one */
104	if (strcmp(device_get_nameunit(dev), "am335x_scm0") != 0)
105		return (ENXIO);
106
107	device_set_desc(dev, "AM335x Control Module Extension");
108
109	return (BUS_PROBE_DEFAULT);
110}
111
112static int
113am335x_scm_attach(device_t dev)
114{
115	struct am335x_scm_softc *sc;
116	struct sysctl_ctx_list *ctx;
117	struct sysctl_oid_list *tree;
118	uint32_t reg;
119	phandle_t opp_table;
120	int err;
121
122	sc = device_get_softc(dev);
123
124	/* FIXME: For now; Go and kidnap syscon from opp-table */
125	opp_table = OF_finddevice("/opp-table");
126	if (opp_table == -1) {
127		device_printf(dev, "Cant find /opp-table\n");
128		return (ENXIO);
129	}
130	if (!OF_hasprop(opp_table, "syscon")) {
131		device_printf(dev, "/opp-table missing syscon property\n");
132		return (ENXIO);
133	}
134	err = syscon_get_by_ofw_property(dev, opp_table, "syscon", &sc->syscon);
135	if (err) {
136		device_printf(dev, "Failed to get syscon\n");
137		return (ENXIO);
138	}
139
140	/* Reset the digital outputs. */
141	SYSCON_WRITE_4(sc->syscon, SCM_BGAP_CTRL, 0);
142	reg = SYSCON_READ_4(sc->syscon, SCM_BGAP_CTRL);
143	DELAY(500);
144	/* Set continous mode. */
145	SYSCON_WRITE_4(sc->syscon, SCM_BGAP_CTRL, SCM_BGAP_CONTCONV);
146	reg = SYSCON_READ_4(sc->syscon, SCM_BGAP_CTRL);
147	DELAY(500);
148	/* Start the ADC conversion. */
149	reg = SCM_BGAP_CLRZ | SCM_BGAP_CONTCONV | SCM_BGAP_SOC;
150	SYSCON_WRITE_4(sc->syscon, SCM_BGAP_CTRL, reg);
151
152	/* Temperature sysctl. */
153        ctx = device_get_sysctl_ctx(dev);
154	tree = SYSCTL_CHILDREN(device_get_sysctl_tree(dev));
155	sc->sc_temp_oid = SYSCTL_ADD_PROC(ctx, tree, OID_AUTO,
156	    "temperature", CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
157	    dev, 0, am335x_scm_temp_sysctl, "IK", "Current temperature");
158
159	return (0);
160}
161
162static int
163am335x_scm_detach(device_t dev)
164{
165	struct am335x_scm_softc *sc;
166
167	sc = device_get_softc(dev);
168
169	/* Remove temperature sysctl. */
170	if (sc->sc_temp_oid != NULL)
171		sysctl_remove_oid(sc->sc_temp_oid, 1, 0);
172
173	/* Stop the bandgap ADC. */
174	SYSCON_WRITE_4(sc->syscon, SCM_BGAP_CTRL, SCM_BGAP_BGOFF);
175
176	return (0);
177}
178
179static device_method_t am335x_scm_methods[] = {
180	DEVMETHOD(device_identify,	am335x_scm_identify),
181	DEVMETHOD(device_probe,		am335x_scm_probe),
182	DEVMETHOD(device_attach,	am335x_scm_attach),
183	DEVMETHOD(device_detach,	am335x_scm_detach),
184
185	DEVMETHOD_END
186};
187
188static driver_t am335x_scm_driver = {
189	"am335x_scm",
190	am335x_scm_methods,
191	sizeof(struct am335x_scm_softc),
192};
193
194static devclass_t am335x_scm_devclass;
195
196DRIVER_MODULE(am335x_scm, ti_scm, am335x_scm_driver, am335x_scm_devclass, 0, 0);
197MODULE_VERSION(am335x_scm, 1);
198MODULE_DEPEND(am335x_scm, ti_scm_syscon, 1, 1, 1);
199