xref: /freebsd/sys/arm/ti/clk/ti_gate_clock.c (revision b3e7694832e81d7a904a10f525f8797b753bf0d3)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2020 Oskar Holmlund <oskar.holmlund@ohdata.se>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
20  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
22  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/conf.h>
33 #include <sys/bus.h>
34 #include <sys/kernel.h>
35 #include <sys/module.h>
36 #include <sys/systm.h>
37 #include <sys/libkern.h>
38 
39 #include <machine/bus.h>
40 #include <dev/fdt/simplebus.h>
41 
42 #include <dev/extres/clk/clk_gate.h>
43 #include <dev/ofw/ofw_bus.h>
44 #include <dev/ofw/ofw_bus_subr.h>
45 
46 #include "clock_common.h"
47 
48 #define DEBUG_GATE	0
49 
50 #if DEBUG_GATE
51 #define DPRINTF(dev, msg...) device_printf(dev, msg)
52 #else
53 #define DPRINTF(dev, msg...)
54 #endif
55 
56 /*
57  * Devicetree description
58  * Documentation/devicetree/bindings/clock/ti/gate.txt
59  */
60 
61 struct ti_gate_softc {
62 	device_t		sc_dev;
63 	bool			attach_done;
64 	uint8_t			sc_type;
65 
66 	struct clk_gate_def	gate_def;
67 	struct clock_cell_info  clock_cell;
68 	struct clkdom		*clkdom;
69 };
70 
71 static int ti_gate_probe(device_t dev);
72 static int ti_gate_attach(device_t dev);
73 static int ti_gate_detach(device_t dev);
74 
75 #define TI_GATE_CLOCK			7
76 #define TI_WAIT_GATE_CLOCK		6
77 #define TI_DSS_GATE_CLOCK		5
78 #define TI_AM35XX_GATE_CLOCK		4
79 #define TI_CLKDM_GATE_CLOCK		3
80 #define TI_HSDIV_GATE_CLOCK		2
81 #define TI_COMPOSITE_NO_WAIT_GATE_CLOCK	1
82 #define TI_GATE_END			0
83 
84 static struct ofw_compat_data compat_data[] = {
85 	{ "ti,gate-clock",			TI_GATE_CLOCK },
86 	{ "ti,wait-gate-clock",			TI_WAIT_GATE_CLOCK },
87 	{ "ti,dss-gate-clock",			TI_DSS_GATE_CLOCK },
88 	{ "ti,am35xx-gate-clock",		TI_AM35XX_GATE_CLOCK },
89 	{ "ti,clkdm-gate-clock",		TI_CLKDM_GATE_CLOCK },
90 	{ "ti,hsdiv-gate-cloc",			TI_HSDIV_GATE_CLOCK },
91 	{ "ti,composite-no-wait-gate-clock",	TI_COMPOSITE_NO_WAIT_GATE_CLOCK },
92 	{ NULL,					TI_GATE_END }
93 };
94 
95 static int
96 ti_gate_probe(device_t dev)
97 {
98 	if (!ofw_bus_status_okay(dev))
99 		return (ENXIO);
100 
101 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
102 		return (ENXIO);
103 
104 	device_set_desc(dev, "TI Gate Clock");
105 
106 	return (BUS_PROBE_DEFAULT);
107 }
108 
109 static int
110 register_clk(struct ti_gate_softc *sc) {
111 	int err;
112 	sc->clkdom = clkdom_create(sc->sc_dev);
113 	if (sc->clkdom == NULL) {
114 		DPRINTF(sc->sc_dev, "Failed to create clkdom\n");
115 		return ENXIO;
116 	}
117 
118 	err = clknode_gate_register(sc->clkdom, &sc->gate_def);
119 	if (err) {
120 		DPRINTF(sc->sc_dev, "clknode_gate_register failed %x\n", err);
121 		return ENXIO;
122 	}
123 
124 	err = clkdom_finit(sc->clkdom);
125 	if (err) {
126 		DPRINTF(sc->sc_dev, "Clk domain finit fails %x.\n", err);
127 		return ENXIO;
128 	}
129 
130 	return (0);
131 }
132 
133 static int
134 ti_gate_attach(device_t dev)
135 {
136 	struct ti_gate_softc *sc;
137 	phandle_t node;
138 	int err;
139 	cell_t value;
140 
141 	sc = device_get_softc(dev);
142 	sc->sc_dev = dev;
143 	node = ofw_bus_get_node(dev);
144 
145 	/* Get the compatible type */
146 	sc->sc_type = ofw_bus_search_compatible(dev, compat_data)->ocd_data;
147 
148 	/* Get the content of reg properties */
149 	if (sc->sc_type != TI_CLKDM_GATE_CLOCK) {
150 		OF_getencprop(node, "reg", &value, sizeof(value));
151 		sc->gate_def.offset = value;
152 	}
153 #if DEBUG_GATE
154 	else {
155 		DPRINTF(sc->sc_dev, "no reg (TI_CLKDM_GATE_CLOCK)\n");
156 	}
157 #endif
158 
159 	if (OF_hasprop(node, "ti,bit-shift")) {
160 		OF_getencprop(node, "ti,bit-shift", &value, sizeof(value));
161 		sc->gate_def.shift = value;
162 		DPRINTF(sc->sc_dev, "ti,bit-shift => shift %x\n", sc->gate_def.shift);
163 	}
164 	if (OF_hasprop(node, "ti,set-bit-to-disable")) {
165 		sc->gate_def.on_value = 0;
166 		sc->gate_def.off_value = 1;
167 		DPRINTF(sc->sc_dev,
168 			"on_value = 0, off_value = 1 (ti,set-bit-to-disable)\n");
169 	} else {
170 		sc->gate_def.on_value = 1;
171 		sc->gate_def.off_value = 0;
172 		DPRINTF(sc->sc_dev, "on_value = 1, off_value = 0\n");
173 	}
174 
175 	sc->gate_def.gate_flags = 0x0;
176 
177 	read_clock_cells(sc->sc_dev, &sc->clock_cell);
178 
179 	create_clkdef(sc->sc_dev, &sc->clock_cell, &sc->gate_def.clkdef);
180 
181 	/* Calculate mask */
182 	sc->gate_def.mask = (1 << fls(sc->clock_cell.num_real_clocks)) - 1;
183 	DPRINTF(sc->sc_dev, "num_real_clocks %x gate_def.mask %x\n",
184 		sc->clock_cell.num_real_clocks, sc->gate_def.mask);
185 
186 	err = find_parent_clock_names(sc->sc_dev, &sc->clock_cell, &sc->gate_def.clkdef);
187 
188 	if (err) {
189 		/* free_clkdef will be called in ti_gate_new_pass */
190 		DPRINTF(sc->sc_dev, "find_parent_clock_names failed\n");
191 		return (bus_generic_attach(sc->sc_dev));
192 	}
193 
194 	err = register_clk(sc);
195 
196 	if (err) {
197 		/* free_clkdef will be called in ti_gate_new_pass */
198 		DPRINTF(sc->sc_dev, "register_clk failed\n");
199 		return (bus_generic_attach(sc->sc_dev));
200 	}
201 
202 	sc->attach_done = true;
203 
204 	free_clkdef(&sc->gate_def.clkdef);
205 
206 	return (bus_generic_attach(sc->sc_dev));
207 }
208 
209 static int
210 ti_gate_detach(device_t dev)
211 {
212 	return (EBUSY);
213 }
214 
215 static void
216 ti_gate_new_pass(device_t dev) {
217 	struct ti_gate_softc *sc;
218 	int err;
219 
220 	sc = device_get_softc(dev);
221 
222 	if (sc->attach_done) {
223 		return;
224 	}
225 
226 	err = find_parent_clock_names(sc->sc_dev, &sc->clock_cell, &sc->gate_def.clkdef);
227 	if (err) {
228 		/* free_clkdef will be called in later call to ti_gate_new_pass */
229 		DPRINTF(sc->sc_dev, "new_pass find_parent_clock_names failed\n");
230 		return;
231 	}
232 
233 	err = register_clk(sc);
234 	if (err) {
235 		/* free_clkdef will be called in later call to ti_gate_new_pass */
236 		DPRINTF(sc->sc_dev, "new_pass register_clk failed\n");
237 		return;
238 	}
239 
240 	sc->attach_done = true;
241 
242 	free_clkdef(&sc->gate_def.clkdef);
243 }
244 
245 static device_method_t ti_gate_methods[] = {
246 	/* Device interface */
247 	DEVMETHOD(device_probe,		ti_gate_probe),
248 	DEVMETHOD(device_attach,	ti_gate_attach),
249 	DEVMETHOD(device_detach,	ti_gate_detach),
250 
251 	/* Bus interface */
252 	DEVMETHOD(bus_new_pass,		ti_gate_new_pass),
253 
254 	DEVMETHOD_END
255 };
256 
257 DEFINE_CLASS_0(ti_gate, ti_gate_driver, ti_gate_methods,
258 	sizeof(struct ti_gate_softc));
259 
260 EARLY_DRIVER_MODULE(ti_gate, simplebus, ti_gate_driver, 0, 0,
261     BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
262 MODULE_VERSION(ti_gate, 1);
263