xref: /freebsd/sys/arm/ti/clk/ti_gate_clock.c (revision 96190b4fef3b4a0cc3ca0606b0c4e3e69a5e6717)
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/param.h>
29 #include <sys/conf.h>
30 #include <sys/bus.h>
31 #include <sys/kernel.h>
32 #include <sys/module.h>
33 #include <sys/systm.h>
34 #include <sys/libkern.h>
35 
36 #include <machine/bus.h>
37 #include <dev/fdt/simplebus.h>
38 
39 #include <dev/clk/clk_gate.h>
40 #include <dev/ofw/ofw_bus.h>
41 #include <dev/ofw/ofw_bus_subr.h>
42 
43 #include "clock_common.h"
44 
45 #define DEBUG_GATE	0
46 
47 #if DEBUG_GATE
48 #define DPRINTF(dev, msg...) device_printf(dev, msg)
49 #else
50 #define DPRINTF(dev, msg...)
51 #endif
52 
53 /*
54  * Devicetree description
55  * Documentation/devicetree/bindings/clock/ti/gate.txt
56  */
57 
58 struct ti_gate_softc {
59 	device_t		sc_dev;
60 	bool			attach_done;
61 	uint8_t			sc_type;
62 
63 	struct clk_gate_def	gate_def;
64 	struct clock_cell_info  clock_cell;
65 	struct clkdom		*clkdom;
66 };
67 
68 static int ti_gate_probe(device_t dev);
69 static int ti_gate_attach(device_t dev);
70 static int ti_gate_detach(device_t dev);
71 
72 #define TI_GATE_CLOCK			7
73 #define TI_WAIT_GATE_CLOCK		6
74 #define TI_DSS_GATE_CLOCK		5
75 #define TI_AM35XX_GATE_CLOCK		4
76 #define TI_CLKDM_GATE_CLOCK		3
77 #define TI_HSDIV_GATE_CLOCK		2
78 #define TI_COMPOSITE_NO_WAIT_GATE_CLOCK	1
79 #define TI_GATE_END			0
80 
81 static struct ofw_compat_data compat_data[] = {
82 	{ "ti,gate-clock",			TI_GATE_CLOCK },
83 	{ "ti,wait-gate-clock",			TI_WAIT_GATE_CLOCK },
84 	{ "ti,dss-gate-clock",			TI_DSS_GATE_CLOCK },
85 	{ "ti,am35xx-gate-clock",		TI_AM35XX_GATE_CLOCK },
86 	{ "ti,clkdm-gate-clock",		TI_CLKDM_GATE_CLOCK },
87 	{ "ti,hsdiv-gate-cloc",			TI_HSDIV_GATE_CLOCK },
88 	{ "ti,composite-no-wait-gate-clock",	TI_COMPOSITE_NO_WAIT_GATE_CLOCK },
89 	{ NULL,					TI_GATE_END }
90 };
91 
92 static int
93 ti_gate_probe(device_t dev)
94 {
95 	if (!ofw_bus_status_okay(dev))
96 		return (ENXIO);
97 
98 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
99 		return (ENXIO);
100 
101 	device_set_desc(dev, "TI Gate Clock");
102 
103 	return (BUS_PROBE_DEFAULT);
104 }
105 
106 static int
107 register_clk(struct ti_gate_softc *sc) {
108 	int err;
109 	sc->clkdom = clkdom_create(sc->sc_dev);
110 	if (sc->clkdom == NULL) {
111 		DPRINTF(sc->sc_dev, "Failed to create clkdom\n");
112 		return ENXIO;
113 	}
114 
115 	err = clknode_gate_register(sc->clkdom, &sc->gate_def);
116 	if (err) {
117 		DPRINTF(sc->sc_dev, "clknode_gate_register failed %x\n", err);
118 		return ENXIO;
119 	}
120 
121 	err = clkdom_finit(sc->clkdom);
122 	if (err) {
123 		DPRINTF(sc->sc_dev, "Clk domain finit fails %x.\n", err);
124 		return ENXIO;
125 	}
126 
127 	return (0);
128 }
129 
130 static int
131 ti_gate_attach(device_t dev)
132 {
133 	struct ti_gate_softc *sc;
134 	phandle_t node;
135 	int err;
136 	cell_t value;
137 
138 	sc = device_get_softc(dev);
139 	sc->sc_dev = dev;
140 	node = ofw_bus_get_node(dev);
141 
142 	/* Get the compatible type */
143 	sc->sc_type = ofw_bus_search_compatible(dev, compat_data)->ocd_data;
144 
145 	/* Get the content of reg properties */
146 	if (sc->sc_type != TI_CLKDM_GATE_CLOCK) {
147 		OF_getencprop(node, "reg", &value, sizeof(value));
148 		sc->gate_def.offset = value;
149 	}
150 #if DEBUG_GATE
151 	else {
152 		DPRINTF(sc->sc_dev, "no reg (TI_CLKDM_GATE_CLOCK)\n");
153 	}
154 #endif
155 
156 	if (OF_hasprop(node, "ti,bit-shift")) {
157 		OF_getencprop(node, "ti,bit-shift", &value, sizeof(value));
158 		sc->gate_def.shift = value;
159 		DPRINTF(sc->sc_dev, "ti,bit-shift => shift %x\n", sc->gate_def.shift);
160 	}
161 	if (OF_hasprop(node, "ti,set-bit-to-disable")) {
162 		sc->gate_def.on_value = 0;
163 		sc->gate_def.off_value = 1;
164 		DPRINTF(sc->sc_dev,
165 			"on_value = 0, off_value = 1 (ti,set-bit-to-disable)\n");
166 	} else {
167 		sc->gate_def.on_value = 1;
168 		sc->gate_def.off_value = 0;
169 		DPRINTF(sc->sc_dev, "on_value = 1, off_value = 0\n");
170 	}
171 
172 	sc->gate_def.gate_flags = 0x0;
173 
174 	read_clock_cells(sc->sc_dev, &sc->clock_cell);
175 
176 	create_clkdef(sc->sc_dev, &sc->clock_cell, &sc->gate_def.clkdef);
177 
178 	/* Calculate mask */
179 	sc->gate_def.mask = (1 << fls(sc->clock_cell.num_real_clocks)) - 1;
180 	DPRINTF(sc->sc_dev, "num_real_clocks %x gate_def.mask %x\n",
181 		sc->clock_cell.num_real_clocks, sc->gate_def.mask);
182 
183 	err = find_parent_clock_names(sc->sc_dev, &sc->clock_cell, &sc->gate_def.clkdef);
184 
185 	if (err) {
186 		/* free_clkdef will be called in ti_gate_new_pass */
187 		DPRINTF(sc->sc_dev, "find_parent_clock_names failed\n");
188 		return (bus_generic_attach(sc->sc_dev));
189 	}
190 
191 	err = register_clk(sc);
192 
193 	if (err) {
194 		/* free_clkdef will be called in ti_gate_new_pass */
195 		DPRINTF(sc->sc_dev, "register_clk failed\n");
196 		return (bus_generic_attach(sc->sc_dev));
197 	}
198 
199 	sc->attach_done = true;
200 
201 	free_clkdef(&sc->gate_def.clkdef);
202 
203 	return (bus_generic_attach(sc->sc_dev));
204 }
205 
206 static int
207 ti_gate_detach(device_t dev)
208 {
209 	return (EBUSY);
210 }
211 
212 static void
213 ti_gate_new_pass(device_t dev) {
214 	struct ti_gate_softc *sc;
215 	int err;
216 
217 	sc = device_get_softc(dev);
218 
219 	if (sc->attach_done) {
220 		return;
221 	}
222 
223 	err = find_parent_clock_names(sc->sc_dev, &sc->clock_cell, &sc->gate_def.clkdef);
224 	if (err) {
225 		/* free_clkdef will be called in later call to ti_gate_new_pass */
226 		DPRINTF(sc->sc_dev, "new_pass find_parent_clock_names failed\n");
227 		return;
228 	}
229 
230 	err = register_clk(sc);
231 	if (err) {
232 		/* free_clkdef will be called in later call to ti_gate_new_pass */
233 		DPRINTF(sc->sc_dev, "new_pass register_clk failed\n");
234 		return;
235 	}
236 
237 	sc->attach_done = true;
238 
239 	free_clkdef(&sc->gate_def.clkdef);
240 }
241 
242 static device_method_t ti_gate_methods[] = {
243 	/* Device interface */
244 	DEVMETHOD(device_probe,		ti_gate_probe),
245 	DEVMETHOD(device_attach,	ti_gate_attach),
246 	DEVMETHOD(device_detach,	ti_gate_detach),
247 
248 	/* Bus interface */
249 	DEVMETHOD(bus_new_pass,		ti_gate_new_pass),
250 
251 	DEVMETHOD_END
252 };
253 
254 DEFINE_CLASS_0(ti_gate, ti_gate_driver, ti_gate_methods,
255 	sizeof(struct ti_gate_softc));
256 
257 EARLY_DRIVER_MODULE(ti_gate, simplebus, ti_gate_driver, 0, 0,
258     BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
259 MODULE_VERSION(ti_gate, 1);
260