xref: /freebsd/sys/arm/ti/clk/ti_gate_clock.c (revision 6ef644f5889afbd0f681b08ed1a2f369524af83e)
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 #include <sys/param.h>
30 #include <sys/conf.h>
31 #include <sys/bus.h>
32 #include <sys/kernel.h>
33 #include <sys/module.h>
34 #include <sys/systm.h>
35 #include <sys/libkern.h>
36 
37 #include <machine/bus.h>
38 #include <dev/fdt/simplebus.h>
39 
40 #include <dev/extres/clk/clk_gate.h>
41 #include <dev/ofw/ofw_bus.h>
42 #include <dev/ofw/ofw_bus_subr.h>
43 
44 #include "clock_common.h"
45 
46 #define DEBUG_GATE	0
47 
48 #if DEBUG_GATE
49 #define DPRINTF(dev, msg...) device_printf(dev, msg)
50 #else
51 #define DPRINTF(dev, msg...)
52 #endif
53 
54 /*
55  * Devicetree description
56  * Documentation/devicetree/bindings/clock/ti/gate.txt
57  */
58 
59 struct ti_gate_softc {
60 	device_t		sc_dev;
61 	bool			attach_done;
62 	uint8_t			sc_type;
63 
64 	struct clk_gate_def	gate_def;
65 	struct clock_cell_info  clock_cell;
66 	struct clkdom		*clkdom;
67 };
68 
69 static int ti_gate_probe(device_t dev);
70 static int ti_gate_attach(device_t dev);
71 static int ti_gate_detach(device_t dev);
72 
73 #define TI_GATE_CLOCK			7
74 #define TI_WAIT_GATE_CLOCK		6
75 #define TI_DSS_GATE_CLOCK		5
76 #define TI_AM35XX_GATE_CLOCK		4
77 #define TI_CLKDM_GATE_CLOCK		3
78 #define TI_HSDIV_GATE_CLOCK		2
79 #define TI_COMPOSITE_NO_WAIT_GATE_CLOCK	1
80 #define TI_GATE_END			0
81 
82 static struct ofw_compat_data compat_data[] = {
83 	{ "ti,gate-clock",			TI_GATE_CLOCK },
84 	{ "ti,wait-gate-clock",			TI_WAIT_GATE_CLOCK },
85 	{ "ti,dss-gate-clock",			TI_DSS_GATE_CLOCK },
86 	{ "ti,am35xx-gate-clock",		TI_AM35XX_GATE_CLOCK },
87 	{ "ti,clkdm-gate-clock",		TI_CLKDM_GATE_CLOCK },
88 	{ "ti,hsdiv-gate-cloc",			TI_HSDIV_GATE_CLOCK },
89 	{ "ti,composite-no-wait-gate-clock",	TI_COMPOSITE_NO_WAIT_GATE_CLOCK },
90 	{ NULL,					TI_GATE_END }
91 };
92 
93 static int
94 ti_gate_probe(device_t dev)
95 {
96 	if (!ofw_bus_status_okay(dev))
97 		return (ENXIO);
98 
99 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
100 		return (ENXIO);
101 
102 	device_set_desc(dev, "TI Gate Clock");
103 
104 	return (BUS_PROBE_DEFAULT);
105 }
106 
107 static int
108 register_clk(struct ti_gate_softc *sc) {
109 	int err;
110 	sc->clkdom = clkdom_create(sc->sc_dev);
111 	if (sc->clkdom == NULL) {
112 		DPRINTF(sc->sc_dev, "Failed to create clkdom\n");
113 		return ENXIO;
114 	}
115 
116 	err = clknode_gate_register(sc->clkdom, &sc->gate_def);
117 	if (err) {
118 		DPRINTF(sc->sc_dev, "clknode_gate_register failed %x\n", err);
119 		return ENXIO;
120 	}
121 
122 	err = clkdom_finit(sc->clkdom);
123 	if (err) {
124 		DPRINTF(sc->sc_dev, "Clk domain finit fails %x.\n", err);
125 		return ENXIO;
126 	}
127 
128 	return (0);
129 }
130 
131 static int
132 ti_gate_attach(device_t dev)
133 {
134 	struct ti_gate_softc *sc;
135 	phandle_t node;
136 	int err;
137 	cell_t value;
138 
139 	sc = device_get_softc(dev);
140 	sc->sc_dev = dev;
141 	node = ofw_bus_get_node(dev);
142 
143 	/* Get the compatible type */
144 	sc->sc_type = ofw_bus_search_compatible(dev, compat_data)->ocd_data;
145 
146 	/* Get the content of reg properties */
147 	if (sc->sc_type != TI_CLKDM_GATE_CLOCK) {
148 		OF_getencprop(node, "reg", &value, sizeof(value));
149 		sc->gate_def.offset = value;
150 	}
151 #if DEBUG_GATE
152 	else {
153 		DPRINTF(sc->sc_dev, "no reg (TI_CLKDM_GATE_CLOCK)\n");
154 	}
155 #endif
156 
157 	if (OF_hasprop(node, "ti,bit-shift")) {
158 		OF_getencprop(node, "ti,bit-shift", &value, sizeof(value));
159 		sc->gate_def.shift = value;
160 		DPRINTF(sc->sc_dev, "ti,bit-shift => shift %x\n", sc->gate_def.shift);
161 	}
162 	if (OF_hasprop(node, "ti,set-bit-to-disable")) {
163 		sc->gate_def.on_value = 0;
164 		sc->gate_def.off_value = 1;
165 		DPRINTF(sc->sc_dev,
166 			"on_value = 0, off_value = 1 (ti,set-bit-to-disable)\n");
167 	} else {
168 		sc->gate_def.on_value = 1;
169 		sc->gate_def.off_value = 0;
170 		DPRINTF(sc->sc_dev, "on_value = 1, off_value = 0\n");
171 	}
172 
173 	sc->gate_def.gate_flags = 0x0;
174 
175 	read_clock_cells(sc->sc_dev, &sc->clock_cell);
176 
177 	create_clkdef(sc->sc_dev, &sc->clock_cell, &sc->gate_def.clkdef);
178 
179 	/* Calculate mask */
180 	sc->gate_def.mask = (1 << fls(sc->clock_cell.num_real_clocks)) - 1;
181 	DPRINTF(sc->sc_dev, "num_real_clocks %x gate_def.mask %x\n",
182 		sc->clock_cell.num_real_clocks, sc->gate_def.mask);
183 
184 	err = find_parent_clock_names(sc->sc_dev, &sc->clock_cell, &sc->gate_def.clkdef);
185 
186 	if (err) {
187 		/* free_clkdef will be called in ti_gate_new_pass */
188 		DPRINTF(sc->sc_dev, "find_parent_clock_names failed\n");
189 		return (bus_generic_attach(sc->sc_dev));
190 	}
191 
192 	err = register_clk(sc);
193 
194 	if (err) {
195 		/* free_clkdef will be called in ti_gate_new_pass */
196 		DPRINTF(sc->sc_dev, "register_clk failed\n");
197 		return (bus_generic_attach(sc->sc_dev));
198 	}
199 
200 	sc->attach_done = true;
201 
202 	free_clkdef(&sc->gate_def.clkdef);
203 
204 	return (bus_generic_attach(sc->sc_dev));
205 }
206 
207 static int
208 ti_gate_detach(device_t dev)
209 {
210 	return (EBUSY);
211 }
212 
213 static void
214 ti_gate_new_pass(device_t dev) {
215 	struct ti_gate_softc *sc;
216 	int err;
217 
218 	sc = device_get_softc(dev);
219 
220 	if (sc->attach_done) {
221 		return;
222 	}
223 
224 	err = find_parent_clock_names(sc->sc_dev, &sc->clock_cell, &sc->gate_def.clkdef);
225 	if (err) {
226 		/* free_clkdef will be called in later call to ti_gate_new_pass */
227 		DPRINTF(sc->sc_dev, "new_pass find_parent_clock_names failed\n");
228 		return;
229 	}
230 
231 	err = register_clk(sc);
232 	if (err) {
233 		/* free_clkdef will be called in later call to ti_gate_new_pass */
234 		DPRINTF(sc->sc_dev, "new_pass register_clk failed\n");
235 		return;
236 	}
237 
238 	sc->attach_done = true;
239 
240 	free_clkdef(&sc->gate_def.clkdef);
241 }
242 
243 static device_method_t ti_gate_methods[] = {
244 	/* Device interface */
245 	DEVMETHOD(device_probe,		ti_gate_probe),
246 	DEVMETHOD(device_attach,	ti_gate_attach),
247 	DEVMETHOD(device_detach,	ti_gate_detach),
248 
249 	/* Bus interface */
250 	DEVMETHOD(bus_new_pass,		ti_gate_new_pass),
251 
252 	DEVMETHOD_END
253 };
254 
255 DEFINE_CLASS_0(ti_gate, ti_gate_driver, ti_gate_methods,
256 	sizeof(struct ti_gate_softc));
257 
258 EARLY_DRIVER_MODULE(ti_gate, simplebus, ti_gate_driver, 0, 0,
259     BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
260 MODULE_VERSION(ti_gate, 1);
261