1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2019 Emmanuel Vadot <[email protected]>
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  * $FreeBSD$
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/bus.h>
36 
37 #include <dev/extres/clk/clk.h>
38 
39 #include <arm/allwinner/clkng/aw_clk.h>
40 #include <arm/allwinner/clkng/aw_clk_nmm.h>
41 
42 #include "clkdev_if.h"
43 
44 /*
45  * clknode for clocks matching the formula :
46  *
47  * clk = clkin * n / m0 / m1
48  *
49  */
50 
51 struct aw_clk_nmm_sc {
52 	uint32_t	offset;
53 
54 	struct aw_clk_factor	n;
55 	struct aw_clk_factor	m0;
56 	struct aw_clk_factor	m1;
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 static int
aw_clk_nmm_init(struct clknode * clk,device_t dev)75 aw_clk_nmm_init(struct clknode *clk, device_t dev)
76 {
77 	struct aw_clk_nmm_sc *sc;
78 
79 	sc = clknode_get_softc(clk);
80 
81 	clknode_init_parent_idx(clk, 0);
82 	return (0);
83 }
84 
85 static int
aw_clk_nmm_set_gate(struct clknode * clk,bool enable)86 aw_clk_nmm_set_gate(struct clknode *clk, bool enable)
87 {
88 	struct aw_clk_nmm_sc *sc;
89 	uint32_t val;
90 
91 	sc = clknode_get_softc(clk);
92 
93 	if ((sc->flags & AW_CLK_HAS_GATE) == 0)
94 		return (0);
95 
96 	DEVICE_LOCK(clk);
97 	READ4(clk, sc->offset, &val);
98 	if (enable)
99 		val |= (1 << sc->gate_shift);
100 	else
101 		val &= ~(1 << sc->gate_shift);
102 	WRITE4(clk, sc->offset, val);
103 	DEVICE_UNLOCK(clk);
104 
105 	return (0);
106 }
107 
108 static uint64_t
aw_clk_nmm_find_best(struct aw_clk_nmm_sc * sc,uint64_t fparent,uint64_t * fout,uint32_t * factor_n,uint32_t * factor_m0,uint32_t * factor_m1)109 aw_clk_nmm_find_best(struct aw_clk_nmm_sc *sc, uint64_t fparent, uint64_t *fout,
110   uint32_t *factor_n, uint32_t *factor_m0, uint32_t *factor_m1)
111 {
112 	uint64_t cur, best;
113 	uint32_t n, m0, m1;
114 	uint32_t max_n, max_m0, max_m1;
115 	uint32_t min_n, min_m0, min_m1;
116 
117 	*factor_n = *factor_m0 = *factor_m1 = 0;
118 
119 	max_n = aw_clk_factor_get_max(&sc->n);
120 	min_n = aw_clk_factor_get_min(&sc->n);
121 	max_m0 = aw_clk_factor_get_max(&sc->m0);
122 	min_m0 = aw_clk_factor_get_min(&sc->m0);
123 	max_m1 = aw_clk_factor_get_max(&sc->m1);
124 	min_m1 = aw_clk_factor_get_min(&sc->m1);
125 
126 	for (m0 = min_m0; m0 <= max_m0; ) {
127 		for (m1 = min_m1; m1 <= max_m1; ) {
128 			for (n = min_n; n <= max_n; ) {
129 				cur = fparent * n / m0 / m1;
130 				if (abs(*fout - cur) < abs(*fout - best)) {
131 					best = cur;
132 					*factor_n = n;
133 					*factor_m0 = m0;
134 					*factor_m1 = m1;
135 				}
136 				n++;
137 			}
138 			m1++;
139 		}
140 		m0++;
141 	}
142 
143 	return (best);
144 }
145 
146 static int
aw_clk_nmm_set_freq(struct clknode * clk,uint64_t fparent,uint64_t * fout,int flags,int * stop)147 aw_clk_nmm_set_freq(struct clknode *clk, uint64_t fparent, uint64_t *fout,
148     int flags, int *stop)
149 {
150 	struct aw_clk_nmm_sc *sc;
151 	uint64_t cur, best;
152 	uint32_t val, n, m0, m1, best_n, best_m0, best_m1;
153 	int retry;
154 
155 	sc = clknode_get_softc(clk);
156 
157 	best = cur = 0;
158 
159 	best = aw_clk_nmm_find_best(sc, fparent, fout,
160 	    &best_n, &best_m0, &best_m1);
161 
162 	if ((flags & CLK_SET_DRYRUN) != 0) {
163 		*fout = best;
164 		*stop = 1;
165 		return (0);
166 	}
167 
168 	if ((best < *fout) &&
169 	  ((flags & CLK_SET_ROUND_DOWN) == 0)) {
170 		*stop = 1;
171 		return (ERANGE);
172 	}
173 	if ((best > *fout) &&
174 	  ((flags & CLK_SET_ROUND_UP) == 0)) {
175 		*stop = 1;
176 		return (ERANGE);
177 	}
178 
179 	DEVICE_LOCK(clk);
180 	READ4(clk, sc->offset, &val);
181 
182 	n = aw_clk_factor_get_value(&sc->n, best_n);
183 	m0 = aw_clk_factor_get_value(&sc->m0, best_m0);
184 	m1 = aw_clk_factor_get_value(&sc->m1, best_m1);
185 	val &= ~sc->n.mask;
186 	val &= ~sc->m0.mask;
187 	val &= ~sc->m1.mask;
188 	val |= n << sc->n.shift;
189 	val |= m0 << sc->m0.shift;
190 	val |= m1 << sc->m1.shift;
191 
192 	WRITE4(clk, sc->offset, val);
193 	DEVICE_UNLOCK(clk);
194 
195 	if ((sc->flags & AW_CLK_HAS_LOCK) != 0) {
196 		for (retry = 0; retry < sc->lock_retries; retry++) {
197 			READ4(clk, sc->offset, &val);
198 			if ((val & (1 << sc->lock_shift)) != 0)
199 				break;
200 			DELAY(1000);
201 		}
202 	}
203 
204 	*fout = best;
205 	*stop = 1;
206 
207 	return (0);
208 }
209 
210 static int
aw_clk_nmm_recalc(struct clknode * clk,uint64_t * freq)211 aw_clk_nmm_recalc(struct clknode *clk, uint64_t *freq)
212 {
213 	struct aw_clk_nmm_sc *sc;
214 	uint32_t val, n, m0, m1;
215 
216 	sc = clknode_get_softc(clk);
217 
218 	DEVICE_LOCK(clk);
219 	READ4(clk, sc->offset, &val);
220 	DEVICE_UNLOCK(clk);
221 
222 	n = aw_clk_get_factor(val, &sc->n);
223 	m0 = aw_clk_get_factor(val, &sc->m0);
224 	m1 = aw_clk_get_factor(val, &sc->m1);
225 
226 	*freq = *freq * n / m0 / m1;
227 
228 	return (0);
229 }
230 
231 static clknode_method_t aw_nmm_clknode_methods[] = {
232 	/* Device interface */
233 	CLKNODEMETHOD(clknode_init,		aw_clk_nmm_init),
234 	CLKNODEMETHOD(clknode_set_gate,		aw_clk_nmm_set_gate),
235 	CLKNODEMETHOD(clknode_recalc_freq,	aw_clk_nmm_recalc),
236 	CLKNODEMETHOD(clknode_set_freq,		aw_clk_nmm_set_freq),
237 	CLKNODEMETHOD_END
238 };
239 
240 DEFINE_CLASS_1(aw_nmm_clknode, aw_nmm_clknode_class, aw_nmm_clknode_methods,
241     sizeof(struct aw_clk_nmm_sc), clknode_class);
242 
243 int
aw_clk_nmm_register(struct clkdom * clkdom,struct aw_clk_nmm_def * clkdef)244 aw_clk_nmm_register(struct clkdom *clkdom, struct aw_clk_nmm_def *clkdef)
245 {
246 	struct clknode *clk;
247 	struct aw_clk_nmm_sc *sc;
248 
249 	clk = clknode_create(clkdom, &aw_nmm_clknode_class, &clkdef->clkdef);
250 	if (clk == NULL)
251 		return (1);
252 
253 	sc = clknode_get_softc(clk);
254 
255 	sc->offset = clkdef->offset;
256 
257 	sc->n.shift = clkdef->n.shift;
258 	sc->n.width = clkdef->n.width;
259 	sc->n.mask = ((1 << sc->n.width) - 1) << sc->n.shift;
260 	sc->n.value = clkdef->n.value;
261 	sc->n.flags = clkdef->n.flags;
262 
263 	sc->m0.shift = clkdef->m0.shift;
264 	sc->m0.width = clkdef->m0.width;
265 	sc->m0.mask = ((1 << sc->m0.width) - 1) << sc->m0.shift;
266 	sc->m0.value = clkdef->m0.value;
267 	sc->m0.flags = clkdef->m0.flags;
268 
269 	sc->m1.shift = clkdef->m1.shift;
270 	sc->m1.width = clkdef->m1.width;
271 	sc->m1.mask = ((1 << sc->m1.width) - 1) << sc->m1.shift;
272 	sc->m1.value = clkdef->m1.value;
273 	sc->m1.flags = clkdef->m1.flags;
274 
275 	sc->gate_shift = clkdef->gate_shift;
276 
277 	sc->lock_shift = clkdef->lock_shift;
278 	sc->lock_retries = clkdef->lock_retries;
279 
280 	sc->flags = clkdef->flags;
281 
282 	clknode_register(clkdom, clk);
283 
284 	return (0);
285 }
286