1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 
28 #include <sys/cdefs.h>
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/bus.h>
32 
33 #include <dev/extres/clk/clk.h>
34 
35 #include <arm/allwinner/clkng/aw_clk.h>
36 #include <arm/allwinner/clkng/aw_clk_nmm.h>
37 
38 #include "clkdev_if.h"
39 
40 /*
41  * clknode for clocks matching the formula :
42  *
43  * clk = clkin * n / m0 / m1
44  *
45  */
46 
47 struct aw_clk_nmm_sc {
48 	uint32_t	offset;
49 
50 	struct aw_clk_factor	n;
51 	struct aw_clk_factor	m0;
52 	struct aw_clk_factor	m1;
53 
54 	uint32_t	gate_shift;
55 	uint32_t	lock_shift;
56 	uint32_t	lock_retries;
57 
58 	uint32_t	flags;
59 };
60 
61 #define	WRITE4(_clk, off, val)						\
62 	CLKDEV_WRITE_4(clknode_get_device(_clk), off, val)
63 #define	READ4(_clk, off, val)						\
64 	CLKDEV_READ_4(clknode_get_device(_clk), off, val)
65 #define	DEVICE_LOCK(_clk)							\
66 	CLKDEV_DEVICE_LOCK(clknode_get_device(_clk))
67 #define	DEVICE_UNLOCK(_clk)						\
68 	CLKDEV_DEVICE_UNLOCK(clknode_get_device(_clk))
69 
70 static int
aw_clk_nmm_init(struct clknode * clk,device_t dev)71 aw_clk_nmm_init(struct clknode *clk, device_t dev)
72 {
73 
74 	clknode_init_parent_idx(clk, 0);
75 	return (0);
76 }
77 
78 static int
aw_clk_nmm_set_gate(struct clknode * clk,bool enable)79 aw_clk_nmm_set_gate(struct clknode *clk, bool enable)
80 {
81 	struct aw_clk_nmm_sc *sc;
82 	uint32_t val;
83 
84 	sc = clknode_get_softc(clk);
85 
86 	if ((sc->flags & AW_CLK_HAS_GATE) == 0)
87 		return (0);
88 
89 	DEVICE_LOCK(clk);
90 	READ4(clk, sc->offset, &val);
91 	if (enable)
92 		val |= (1 << sc->gate_shift);
93 	else
94 		val &= ~(1 << sc->gate_shift);
95 	WRITE4(clk, sc->offset, val);
96 	DEVICE_UNLOCK(clk);
97 
98 	return (0);
99 }
100 
101 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)102 aw_clk_nmm_find_best(struct aw_clk_nmm_sc *sc, uint64_t fparent, uint64_t *fout,
103   uint32_t *factor_n, uint32_t *factor_m0, uint32_t *factor_m1)
104 {
105 	uint64_t cur, best;
106 	uint32_t n, m0, m1;
107 	uint32_t max_n, max_m0, max_m1;
108 	uint32_t min_n, min_m0, min_m1;
109 
110 	*factor_n = *factor_m0 = *factor_m1 = 0;
111 
112 	max_n = aw_clk_factor_get_max(&sc->n);
113 	min_n = aw_clk_factor_get_min(&sc->n);
114 	max_m0 = aw_clk_factor_get_max(&sc->m0);
115 	min_m0 = aw_clk_factor_get_min(&sc->m0);
116 	max_m1 = aw_clk_factor_get_max(&sc->m1);
117 	min_m1 = aw_clk_factor_get_min(&sc->m1);
118 
119 	for (m0 = min_m0; m0 <= max_m0; ) {
120 		for (m1 = min_m1; m1 <= max_m1; ) {
121 			for (n = min_n; n <= max_n; ) {
122 				cur = fparent * n / m0 / m1;
123 				if (abs(*fout - cur) < abs(*fout - best)) {
124 					best = cur;
125 					*factor_n = n;
126 					*factor_m0 = m0;
127 					*factor_m1 = m1;
128 				}
129 				n++;
130 			}
131 			m1++;
132 		}
133 		m0++;
134 	}
135 
136 	return (best);
137 }
138 
139 static int
aw_clk_nmm_set_freq(struct clknode * clk,uint64_t fparent,uint64_t * fout,int flags,int * stop)140 aw_clk_nmm_set_freq(struct clknode *clk, uint64_t fparent, uint64_t *fout,
141     int flags, int *stop)
142 {
143 	struct aw_clk_nmm_sc *sc;
144 	uint64_t cur, best;
145 	uint32_t val, n, m0, m1, best_n, best_m0, best_m1;
146 	int retry;
147 
148 	sc = clknode_get_softc(clk);
149 
150 	best = cur = 0;
151 
152 	best = aw_clk_nmm_find_best(sc, fparent, fout,
153 	    &best_n, &best_m0, &best_m1);
154 
155 	if ((flags & CLK_SET_DRYRUN) != 0) {
156 		*fout = best;
157 		*stop = 1;
158 		return (0);
159 	}
160 
161 	if ((best < *fout) &&
162 	  ((flags & CLK_SET_ROUND_DOWN) == 0)) {
163 		*stop = 1;
164 		return (ERANGE);
165 	}
166 	if ((best > *fout) &&
167 	  ((flags & CLK_SET_ROUND_UP) == 0)) {
168 		*stop = 1;
169 		return (ERANGE);
170 	}
171 
172 	DEVICE_LOCK(clk);
173 	READ4(clk, sc->offset, &val);
174 
175 	n = aw_clk_factor_get_value(&sc->n, best_n);
176 	m0 = aw_clk_factor_get_value(&sc->m0, best_m0);
177 	m1 = aw_clk_factor_get_value(&sc->m1, best_m1);
178 	val &= ~sc->n.mask;
179 	val &= ~sc->m0.mask;
180 	val &= ~sc->m1.mask;
181 	val |= n << sc->n.shift;
182 	val |= m0 << sc->m0.shift;
183 	val |= m1 << sc->m1.shift;
184 
185 	WRITE4(clk, sc->offset, val);
186 	DEVICE_UNLOCK(clk);
187 
188 	if ((sc->flags & AW_CLK_HAS_LOCK) != 0) {
189 		for (retry = 0; retry < sc->lock_retries; retry++) {
190 			READ4(clk, sc->offset, &val);
191 			if ((val & (1 << sc->lock_shift)) != 0)
192 				break;
193 			DELAY(1000);
194 		}
195 	}
196 
197 	*fout = best;
198 	*stop = 1;
199 
200 	return (0);
201 }
202 
203 static int
aw_clk_nmm_recalc(struct clknode * clk,uint64_t * freq)204 aw_clk_nmm_recalc(struct clknode *clk, uint64_t *freq)
205 {
206 	struct aw_clk_nmm_sc *sc;
207 	uint32_t val, n, m0, m1;
208 
209 	sc = clknode_get_softc(clk);
210 
211 	DEVICE_LOCK(clk);
212 	READ4(clk, sc->offset, &val);
213 	DEVICE_UNLOCK(clk);
214 
215 	n = aw_clk_get_factor(val, &sc->n);
216 	m0 = aw_clk_get_factor(val, &sc->m0);
217 	m1 = aw_clk_get_factor(val, &sc->m1);
218 
219 	*freq = *freq * n / m0 / m1;
220 
221 	return (0);
222 }
223 
224 static clknode_method_t aw_nmm_clknode_methods[] = {
225 	/* Device interface */
226 	CLKNODEMETHOD(clknode_init,		aw_clk_nmm_init),
227 	CLKNODEMETHOD(clknode_set_gate,		aw_clk_nmm_set_gate),
228 	CLKNODEMETHOD(clknode_recalc_freq,	aw_clk_nmm_recalc),
229 	CLKNODEMETHOD(clknode_set_freq,		aw_clk_nmm_set_freq),
230 	CLKNODEMETHOD_END
231 };
232 
233 DEFINE_CLASS_1(aw_nmm_clknode, aw_nmm_clknode_class, aw_nmm_clknode_methods,
234     sizeof(struct aw_clk_nmm_sc), clknode_class);
235 
236 int
aw_clk_nmm_register(struct clkdom * clkdom,struct aw_clk_nmm_def * clkdef)237 aw_clk_nmm_register(struct clkdom *clkdom, struct aw_clk_nmm_def *clkdef)
238 {
239 	struct clknode *clk;
240 	struct aw_clk_nmm_sc *sc;
241 
242 	clk = clknode_create(clkdom, &aw_nmm_clknode_class, &clkdef->clkdef);
243 	if (clk == NULL)
244 		return (1);
245 
246 	sc = clknode_get_softc(clk);
247 
248 	sc->offset = clkdef->offset;
249 
250 	sc->n.shift = clkdef->n.shift;
251 	sc->n.width = clkdef->n.width;
252 	sc->n.mask = ((1 << sc->n.width) - 1) << sc->n.shift;
253 	sc->n.value = clkdef->n.value;
254 	sc->n.flags = clkdef->n.flags;
255 
256 	sc->m0.shift = clkdef->m0.shift;
257 	sc->m0.width = clkdef->m0.width;
258 	sc->m0.mask = ((1 << sc->m0.width) - 1) << sc->m0.shift;
259 	sc->m0.value = clkdef->m0.value;
260 	sc->m0.flags = clkdef->m0.flags;
261 
262 	sc->m1.shift = clkdef->m1.shift;
263 	sc->m1.width = clkdef->m1.width;
264 	sc->m1.mask = ((1 << sc->m1.width) - 1) << sc->m1.shift;
265 	sc->m1.value = clkdef->m1.value;
266 	sc->m1.flags = clkdef->m1.flags;
267 
268 	sc->gate_shift = clkdef->gate_shift;
269 
270 	sc->lock_shift = clkdef->lock_shift;
271 	sc->lock_retries = clkdef->lock_retries;
272 
273 	sc->flags = clkdef->flags;
274 
275 	clknode_register(clkdom, clk);
276 
277 	return (0);
278 }
279