xref: /freebsd/sys/dev/clk/allwinner/aw_clk_nm.c (revision f5463265955b829775bbb32e1fd0bc11dafc36ce)
1 /*-
2  * Copyright (c) 2017 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_nm.h>
34 
35 #include "clkdev_if.h"
36 
37 /*
38  * clknode for clocks matching the formula :
39  *
40  * clk = clkin / n / m
41  *
42  */
43 
44 struct aw_clk_nm_sc {
45 	uint32_t	offset;
46 
47 	struct aw_clk_factor	m;
48 	struct aw_clk_factor	n;
49 	struct aw_clk_factor	prediv;
50 
51 	uint32_t	mux_shift;
52 	uint32_t	mux_mask;
53 	uint32_t	gate_shift;
54 	uint32_t	lock_shift;
55 	uint32_t	lock_retries;
56 
57 	uint32_t	flags;
58 };
59 
60 #define	WRITE4(_clk, off, val)						\
61 	CLKDEV_WRITE_4(clknode_get_device(_clk), off, val)
62 #define	READ4(_clk, off, val)						\
63 	CLKDEV_READ_4(clknode_get_device(_clk), off, val)
64 #define	DEVICE_LOCK(_clk)							\
65 	CLKDEV_DEVICE_LOCK(clknode_get_device(_clk))
66 #define	DEVICE_UNLOCK(_clk)						\
67 	CLKDEV_DEVICE_UNLOCK(clknode_get_device(_clk))
68 
69 static int
70 aw_clk_nm_init(struct clknode *clk, device_t dev)
71 {
72 	struct aw_clk_nm_sc *sc;
73 	uint32_t val, idx;
74 
75 	sc = clknode_get_softc(clk);
76 
77 	idx = 0;
78 	if ((sc->flags & AW_CLK_HAS_MUX) != 0) {
79 		DEVICE_LOCK(clk);
80 		READ4(clk, sc->offset, &val);
81 		DEVICE_UNLOCK(clk);
82 
83 		idx = (val & sc->mux_mask) >> sc->mux_shift;
84 	}
85 
86 	clknode_init_parent_idx(clk, idx);
87 	return (0);
88 }
89 
90 static int
91 aw_clk_nm_set_gate(struct clknode *clk, bool enable)
92 {
93 	struct aw_clk_nm_sc *sc;
94 	uint32_t val;
95 
96 	sc = clknode_get_softc(clk);
97 
98 	if ((sc->flags & AW_CLK_HAS_GATE) == 0)
99 		return (0);
100 
101 	DEVICE_LOCK(clk);
102 	READ4(clk, sc->offset, &val);
103 	if (enable)
104 		val |= (1 << sc->gate_shift);
105 	else
106 		val &= ~(1 << sc->gate_shift);
107 	WRITE4(clk, sc->offset, val);
108 	DEVICE_UNLOCK(clk);
109 
110 	return (0);
111 }
112 
113 static int
114 aw_clk_nm_set_mux(struct clknode *clk, int index)
115 {
116 	struct aw_clk_nm_sc *sc;
117 	uint32_t val;
118 
119 	sc = clknode_get_softc(clk);
120 
121 	if ((sc->flags & AW_CLK_HAS_MUX) == 0)
122 		return (0);
123 
124 	DEVICE_LOCK(clk);
125 	READ4(clk, sc->offset, &val);
126 	val &= ~sc->mux_mask;
127 	val |= index << sc->mux_shift;
128 	WRITE4(clk, sc->offset, val);
129 	DEVICE_UNLOCK(clk);
130 
131 	return (0);
132 }
133 
134 static uint64_t
135 aw_clk_nm_find_best(struct aw_clk_nm_sc *sc, uint64_t fparent, uint64_t *fout,
136     uint32_t *factor_n, uint32_t *factor_m)
137 {
138 	uint64_t cur, best = 0;
139 	uint32_t m, n, max_m, max_n, min_m, min_n;
140 
141 	*factor_n = *factor_m = 0;
142 
143 	max_m = aw_clk_factor_get_max(&sc->m);
144 	max_n = aw_clk_factor_get_max(&sc->n);
145 	min_m = aw_clk_factor_get_min(&sc->m);
146 	min_n = aw_clk_factor_get_min(&sc->n);
147 
148 	for (m = min_m; m <= max_m; ) {
149 		for (n = min_n; n <= max_n; ) {
150 			cur = fparent / n / m;
151 			if (clk_freq_diff(*fout, cur) <
152 			    clk_freq_diff(*fout, best)) {
153 				best = cur;
154 				*factor_n = n;
155 				*factor_m = m;
156 			}
157 
158 			if ((sc->n.flags & AW_CLK_FACTOR_POWER_OF_TWO) != 0)
159 				n <<= 1;
160 			else
161 				n++;
162 		}
163 		if ((sc->m.flags & AW_CLK_FACTOR_POWER_OF_TWO) != 0)
164 			m <<= 1;
165 		else
166 			m++;
167 	}
168 
169 	return (best);
170 }
171 
172 static int
173 aw_clk_nm_set_freq(struct clknode *clk, uint64_t fparent, uint64_t *fout,
174     int flags, int *stop)
175 {
176 	struct aw_clk_nm_sc *sc;
177 	struct clknode *p_clk;
178 	const char **p_names;
179 	uint64_t cur, best;
180 	uint32_t val, m, n, best_m, best_n;
181 	int p_idx, best_parent, retry;
182 
183 	sc = clknode_get_softc(clk);
184 
185 	best = cur = 0;
186 	best_parent = 0;
187 
188 	if ((sc->flags & AW_CLK_REPARENT) != 0) {
189 		p_names = clknode_get_parent_names(clk);
190 		for (p_idx = 0; p_idx != clknode_get_parents_num(clk); p_idx++) {
191 			p_clk = clknode_find_by_name(p_names[p_idx]);
192 			clknode_get_freq(p_clk, &fparent);
193 
194 			cur = aw_clk_nm_find_best(sc, fparent, fout, &n, &m);
195 			if (clk_freq_diff(*fout, cur) <
196 			    clk_freq_diff(*fout, best)) {
197 				best = cur;
198 				best_parent = p_idx;
199 				best_n = n;
200 				best_m = m;
201 			}
202 		}
203 
204 		p_idx = clknode_get_parent_idx(clk);
205 		p_clk = clknode_get_parent(clk);
206 		clknode_get_freq(p_clk, &fparent);
207 	} else {
208 		best = aw_clk_nm_find_best(sc, fparent, fout,
209 		    &best_n, &best_m);
210 	}
211 
212 	if ((flags & CLK_SET_DRYRUN) != 0) {
213 		*fout = best;
214 		*stop = 1;
215 		return (0);
216 	}
217 
218 	if ((best < *fout) &&
219 	  ((flags & CLK_SET_ROUND_DOWN) == 0)) {
220 		*stop = 1;
221 		printf("best freq (%ju) < requested freq(%ju)\n",
222 		    best, *fout);
223 		return (ERANGE);
224 	}
225 	if ((best > *fout) &&
226 	  ((flags & CLK_SET_ROUND_UP) == 0)) {
227 		*stop = 1;
228 		printf("best freq (%ju) > requested freq(%ju)\n",
229 		    best, *fout);
230 		return (ERANGE);
231 	}
232 
233 	if ((sc->flags & AW_CLK_REPARENT) != 0 && p_idx != best_parent)
234 		clknode_set_parent_by_idx(clk, best_parent);
235 
236 	DEVICE_LOCK(clk);
237 	READ4(clk, sc->offset, &val);
238 
239 	n = aw_clk_factor_get_value(&sc->n, best_n);
240 	m = aw_clk_factor_get_value(&sc->m, best_m);
241 	val &= ~sc->n.mask;
242 	val &= ~sc->m.mask;
243 	val |= n << sc->n.shift;
244 	val |= m << sc->m.shift;
245 
246 	WRITE4(clk, sc->offset, val);
247 	DEVICE_UNLOCK(clk);
248 
249 	if ((sc->flags & AW_CLK_HAS_LOCK) != 0) {
250 		for (retry = 0; retry < sc->lock_retries; retry++) {
251 			READ4(clk, sc->offset, &val);
252 			if ((val & (1 << sc->lock_shift)) != 0)
253 				break;
254 			DELAY(1000);
255 		}
256 	}
257 
258 	*fout = best;
259 	*stop = 1;
260 
261 	return (0);
262 }
263 
264 static int
265 aw_clk_nm_recalc(struct clknode *clk, uint64_t *freq)
266 {
267 	struct aw_clk_nm_sc *sc;
268 	uint32_t val, m, n, prediv;
269 
270 	sc = clknode_get_softc(clk);
271 
272 	DEVICE_LOCK(clk);
273 	READ4(clk, sc->offset, &val);
274 	DEVICE_UNLOCK(clk);
275 
276 	m = aw_clk_get_factor(val, &sc->m);
277 	n = aw_clk_get_factor(val, &sc->n);
278 	if (sc->flags & AW_CLK_HAS_PREDIV)
279 		prediv = aw_clk_get_factor(val, &sc->prediv);
280 	else
281 		prediv = 1;
282 
283 	*freq = *freq / prediv / n / m;
284 
285 	return (0);
286 }
287 
288 static clknode_method_t aw_nm_clknode_methods[] = {
289 	/* Device interface */
290 	CLKNODEMETHOD(clknode_init,		aw_clk_nm_init),
291 	CLKNODEMETHOD(clknode_set_gate,		aw_clk_nm_set_gate),
292 	CLKNODEMETHOD(clknode_set_mux,		aw_clk_nm_set_mux),
293 	CLKNODEMETHOD(clknode_recalc_freq,	aw_clk_nm_recalc),
294 	CLKNODEMETHOD(clknode_set_freq,		aw_clk_nm_set_freq),
295 	CLKNODEMETHOD_END
296 };
297 
298 DEFINE_CLASS_1(aw_nm_clknode, aw_nm_clknode_class, aw_nm_clknode_methods,
299     sizeof(struct aw_clk_nm_sc), clknode_class);
300 
301 int
302 aw_clk_nm_register(struct clkdom *clkdom, struct aw_clk_nm_def *clkdef)
303 {
304 	struct clknode *clk;
305 	struct aw_clk_nm_sc *sc;
306 
307 	clk = clknode_create(clkdom, &aw_nm_clknode_class, &clkdef->clkdef);
308 	if (clk == NULL)
309 		return (1);
310 
311 	sc = clknode_get_softc(clk);
312 
313 	sc->offset = clkdef->offset;
314 
315 	sc->m.shift = clkdef->m.shift;
316 	sc->m.width = clkdef->m.width;
317 	sc->m.mask = ((1 << sc->m.width) - 1) << sc->m.shift;
318 	sc->m.value = clkdef->m.value;
319 	sc->m.flags = clkdef->m.flags;
320 
321 	sc->n.shift = clkdef->n.shift;
322 	sc->n.width = clkdef->n.width;
323 	sc->n.mask = ((1 << sc->n.width) - 1) << sc->n.shift;
324 	sc->n.value = clkdef->n.value;
325 	sc->n.flags = clkdef->n.flags;
326 
327 	sc->prediv.shift = clkdef->prediv.shift;
328 	sc->prediv.width = clkdef->prediv.width;
329 	sc->prediv.mask = ((1 << sc->prediv.width) - 1) << sc->prediv.shift;
330 	sc->prediv.value = clkdef->prediv.value;
331 	sc->prediv.flags = clkdef->prediv.flags;
332 	sc->prediv.cond_shift = clkdef->prediv.cond_shift;
333 	if (clkdef->prediv.cond_width != 0)
334 		sc->prediv.cond_mask = ((1 << clkdef->prediv.cond_width) - 1) << sc->prediv.shift;
335 	else
336 		sc->prediv.cond_mask = clkdef->prediv.cond_mask;
337 	sc->prediv.cond_value = clkdef->prediv.cond_value;
338 
339 	sc->mux_shift = clkdef->mux_shift;
340 	sc->mux_mask = ((1 << clkdef->mux_width) - 1) << sc->mux_shift;
341 
342 	sc->gate_shift = clkdef->gate_shift;
343 
344 	sc->lock_shift = clkdef->lock_shift;
345 	sc->lock_retries = clkdef->lock_retries;
346 
347 	sc->flags = clkdef->flags;
348 
349 	clknode_register(clkdom, clk);
350 
351 	return (0);
352 }
353