xref: /freebsd/sys/dev/clk/allwinner/aw_clk_mipi.c (revision 95eb4b873b6a8b527c5bd78d7191975dfca38998)
1 /*-
2  * Copyright (c) 2019 Emmanuel Vadot <manu@freebsd.org>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
18  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
19  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
20  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
21  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/param.h>
27 #include <sys/systm.h>
28 #include <sys/bus.h>
29 
30 #include <dev/clk/clk.h>
31 
32 #include <dev/clk/allwinner/aw_clk.h>
33 #include <dev/clk/allwinner/aw_clk_mipi.h>
34 
35 #include "clkdev_if.h"
36 
37 /* #define	dprintf(format, arg...)	printf("%s:(%s)" format, __func__, clknode_get_name(clk), arg) */
38 #define	dprintf(format, arg...)
39 
40 /*
41  * clknode for PLL_MIPI :
42  *
43  * clk = (pll_video0 * n * k) / m when vfb_sel=0
44  * clk depend on sint_frac, sdiv2, s6p25_7p5, pll_feedback_div when vfb_sel=1
45  *
46  */
47 
48 struct aw_clk_mipi_sc {
49 	uint32_t	offset;
50 
51 	struct aw_clk_factor	k;
52 	struct aw_clk_factor	m;
53 	struct aw_clk_factor	n;
54 
55 	uint64_t		min_freq;
56 	uint64_t		max_freq;
57 
58 	uint32_t	gate_shift;
59 	uint32_t	lock_shift;
60 	uint32_t	lock_retries;
61 
62 	uint32_t	flags;
63 };
64 
65 #define	WRITE4(_clk, off, val)						\
66 	CLKDEV_WRITE_4(clknode_get_device(_clk), off, val)
67 #define	READ4(_clk, off, val)						\
68 	CLKDEV_READ_4(clknode_get_device(_clk), off, val)
69 #define	DEVICE_LOCK(_clk)							\
70 	CLKDEV_DEVICE_LOCK(clknode_get_device(_clk))
71 #define	DEVICE_UNLOCK(_clk)						\
72 	CLKDEV_DEVICE_UNLOCK(clknode_get_device(_clk))
73 
74 #define	LDO1_EN_SHIFT	23
75 #define	LDO2_EN_SHIFT	22
76 #define	VFB_SEL_SHIFT	16
77 
78 static int
79 aw_clk_mipi_init(struct clknode *clk, device_t dev)
80 {
81 
82 	clknode_init_parent_idx(clk, 0);
83 	return (0);
84 }
85 
86 static int
87 aw_clk_mipi_set_gate(struct clknode *clk, bool enable)
88 {
89 	struct aw_clk_mipi_sc *sc;
90 	uint32_t val;
91 
92 	sc = clknode_get_softc(clk);
93 
94 	dprintf("%sabling gate\n", enable ? "En" : "Dis");
95 	DEVICE_LOCK(clk);
96 	READ4(clk, sc->offset, &val);
97 	if (enable) {
98 		val |= (1 << sc->gate_shift);
99 		val |= (1 << LDO1_EN_SHIFT);
100 		val |= (1 << LDO2_EN_SHIFT);
101 	} else {
102 		val &= ~(1 << sc->gate_shift);
103 		val &= ~(1 << LDO1_EN_SHIFT);
104 		val &= ~(1 << LDO2_EN_SHIFT);
105 	}
106 	WRITE4(clk, sc->offset, val);
107 	DEVICE_UNLOCK(clk);
108 
109 	return (0);
110 }
111 
112 static uint64_t
113 aw_clk_mipi_find_best(struct aw_clk_mipi_sc *sc, uint64_t fparent, uint64_t *fout,
114     uint32_t *factor_k, uint32_t *factor_m, uint32_t *factor_n)
115 {
116 	uint64_t cur, best;
117 	uint32_t n, k, m;
118 
119 	best = 0;
120 	*factor_n = 0;
121 	*factor_k = 0;
122 	*factor_m = 0;
123 
124 	for (n = aw_clk_factor_get_min(&sc->n); n <= aw_clk_factor_get_max(&sc->n); n++) {
125 		for (k = aw_clk_factor_get_min(&sc->k); k <= aw_clk_factor_get_max(&sc->k); k++) {
126 			for (m = aw_clk_factor_get_min(&sc->m); m <= aw_clk_factor_get_max(&sc->m); m++) {
127 				cur = (fparent * n * k) / m;
128 				if ((*fout - cur) < (*fout - best)) {
129 					best = cur;
130 					*factor_n = n;
131 					*factor_k = k;
132 					*factor_m = m;
133 				}
134 				if (best == *fout)
135 					return (best);
136 			}
137 		}
138 	}
139 
140 	return best;
141 }
142 
143 static int
144 aw_clk_mipi_set_freq(struct clknode *clk, uint64_t fparent, uint64_t *fout,
145     int flags, int *stop)
146 {
147 	struct aw_clk_mipi_sc *sc;
148 	uint64_t best = 0;
149 	uint32_t best_k, best_m, best_n;
150 	uint32_t k, m, n;
151 	uint32_t val;
152 	uint32_t retry;
153 
154 	sc = clknode_get_softc(clk);
155 
156 	best = aw_clk_mipi_find_best(sc, fparent, fout, &best_k, &best_m, &best_n);
157 
158 	if (best < sc->min_freq ||
159 	    best > sc->max_freq) {
160 		printf("%s: Cannot set %ju for %s (min=%ju max=%ju)\n",
161 		    __func__, best, clknode_get_name(clk),
162 		    sc->min_freq, sc->max_freq);
163 		return (ERANGE);
164 	}
165 	if ((flags & CLK_SET_DRYRUN) != 0) {
166 		*fout = best;
167 		*stop = 1;
168 		return (0);
169 	}
170 
171 	DEVICE_LOCK(clk);
172 	READ4(clk, sc->offset, &val);
173 	/* Disable clock during freq changes */
174 	val &= ~(1 << sc->gate_shift);
175 	WRITE4(clk, sc->offset, val);
176 
177 	k = aw_clk_factor_get_value(&sc->k, best_k);
178 	n = aw_clk_factor_get_value(&sc->n, best_n);
179 	m = aw_clk_factor_get_value(&sc->m, best_m);
180 	val &= ~sc->k.mask;
181 	val &= ~sc->m.mask;
182 	val &= ~sc->n.mask;
183 	val |= k << sc->k.shift;
184 	val |= m << sc->m.shift;
185 	val |= n << sc->n.shift;
186 
187 	/* Write the clock changes */
188 	WRITE4(clk, sc->offset, val);
189 
190 	/* Enable clock now that we've change it */
191 	val |= 1 << sc->gate_shift;
192 	WRITE4(clk, sc->offset, val);
193 	DEVICE_UNLOCK(clk);
194 
195 	for (retry = 0; retry < sc->lock_retries; retry++) {
196 		READ4(clk, sc->offset, &val);
197 		if ((val & (1 << sc->lock_shift)) != 0)
198 			break;
199 		DELAY(1000);
200 	}
201 
202 	*fout = best;
203 	*stop = 1;
204 
205 	return (0);
206 }
207 
208 static int
209 aw_clk_mipi_recalc(struct clknode *clk, uint64_t *freq)
210 {
211 	struct aw_clk_mipi_sc *sc;
212 	uint32_t val, m, n, k;
213 
214 	sc = clknode_get_softc(clk);
215 
216 	DEVICE_LOCK(clk);
217 	READ4(clk, sc->offset, &val);
218 	DEVICE_UNLOCK(clk);
219 
220 	k = aw_clk_get_factor(val, &sc->k);
221 	m = aw_clk_get_factor(val, &sc->m);
222 	n = aw_clk_get_factor(val, &sc->n);
223 
224 	*freq = (*freq * n * k) / m;
225 
226 	return (0);
227 }
228 
229 static clknode_method_t aw_mipi_clknode_methods[] = {
230 	/* Device interface */
231 	CLKNODEMETHOD(clknode_init,		aw_clk_mipi_init),
232 	CLKNODEMETHOD(clknode_set_gate,		aw_clk_mipi_set_gate),
233 	CLKNODEMETHOD(clknode_recalc_freq,	aw_clk_mipi_recalc),
234 	CLKNODEMETHOD(clknode_set_freq,		aw_clk_mipi_set_freq),
235 	CLKNODEMETHOD_END
236 };
237 
238 DEFINE_CLASS_1(aw_mipi_clknode, aw_mipi_clknode_class, aw_mipi_clknode_methods,
239     sizeof(struct aw_clk_mipi_sc), clknode_class);
240 
241 int
242 aw_clk_mipi_register(struct clkdom *clkdom, struct aw_clk_mipi_def *clkdef)
243 {
244 	struct clknode *clk;
245 	struct aw_clk_mipi_sc *sc;
246 
247 	clk = clknode_create(clkdom, &aw_mipi_clknode_class, &clkdef->clkdef);
248 	if (clk == NULL)
249 		return (1);
250 
251 	sc = clknode_get_softc(clk);
252 
253 	sc->offset = clkdef->offset;
254 
255 	sc->k.shift = clkdef->k.shift;
256 	sc->k.width = clkdef->k.width;
257 	sc->k.mask = ((1 << sc->k.width) - 1) << sc->k.shift;
258 	sc->k.value = clkdef->k.value;
259 	sc->k.flags = clkdef->k.flags;
260 	sc->k.min_value = clkdef->k.min_value;
261 
262 	sc->m.shift = clkdef->m.shift;
263 	sc->m.width = clkdef->m.width;
264 	sc->m.mask = ((1 << sc->m.width) - 1) << sc->m.shift;
265 	sc->m.value = clkdef->m.value;
266 	sc->m.flags = clkdef->m.flags;
267 	sc->m.min_value = clkdef->m.min_value;
268 
269 	sc->n.shift = clkdef->n.shift;
270 	sc->n.width = clkdef->n.width;
271 	sc->n.mask = ((1 << sc->n.width) - 1) << sc->n.shift;
272 	sc->n.value = clkdef->n.value;
273 	sc->n.flags = clkdef->n.flags;
274 	sc->n.min_value = clkdef->n.min_value;
275 
276 	sc->min_freq = clkdef->min_freq;
277 	sc->max_freq = clkdef->max_freq;
278 
279 	sc->gate_shift = clkdef->gate_shift;
280 
281 	sc->lock_shift = clkdef->lock_shift;
282 	sc->lock_retries = clkdef->lock_retries;
283 
284 	sc->flags = clkdef->flags;
285 
286 	clknode_register(clkdom, clk);
287 
288 	return (0);
289 }
290