xref: /f-stack/freebsd/arm/allwinner/clkng/aw_clk_m.c (revision 22ce4aff)
1 /*-
2  * Copyright (c) 2019 Emmanuel Vadot <[email protected]>
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  * $FreeBSD$
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/bus.h>
34 
35 #include <dev/extres/clk/clk.h>
36 
37 #include <arm/allwinner/clkng/aw_clk.h>
38 #include <arm/allwinner/clkng/aw_clk_m.h>
39 
40 #include "clkdev_if.h"
41 
42 /*
43  * clknode for clocks matching the formula :
44  *
45  * clk = clkin / m
46  * And that needs to potentially :
47  * 1) Set the parent freq
48  * 2) Support Setting the parent to a multiple
49  *
50  */
51 
52 struct aw_clk_m_sc {
53 	uint32_t	offset;
54 
55 	struct aw_clk_factor	m;
56 
57 	uint32_t	mux_shift;
58 	uint32_t	mux_mask;
59 	uint32_t	gate_shift;
60 
61 	uint32_t	flags;
62 };
63 
64 #define	WRITE4(_clk, off, val)						\
65 	CLKDEV_WRITE_4(clknode_get_device(_clk), off, val)
66 #define	READ4(_clk, off, val)						\
67 	CLKDEV_READ_4(clknode_get_device(_clk), off, val)
68 #define	DEVICE_LOCK(_clk)							\
69 	CLKDEV_DEVICE_LOCK(clknode_get_device(_clk))
70 #define	DEVICE_UNLOCK(_clk)						\
71 	CLKDEV_DEVICE_UNLOCK(clknode_get_device(_clk))
72 
73 static int
aw_clk_m_init(struct clknode * clk,device_t dev)74 aw_clk_m_init(struct clknode *clk, device_t dev)
75 {
76 	struct aw_clk_m_sc *sc;
77 	uint32_t val, idx;
78 
79 	sc = clknode_get_softc(clk);
80 
81 	idx = 0;
82 	if ((sc->flags & AW_CLK_HAS_MUX) != 0) {
83 		DEVICE_LOCK(clk);
84 		READ4(clk, sc->offset, &val);
85 		DEVICE_UNLOCK(clk);
86 
87 		idx = (val & sc->mux_mask) >> sc->mux_shift;
88 	}
89 
90 	clknode_init_parent_idx(clk, idx);
91 	return (0);
92 }
93 
94 static int
aw_clk_m_set_gate(struct clknode * clk,bool enable)95 aw_clk_m_set_gate(struct clknode *clk, bool enable)
96 {
97 	struct aw_clk_m_sc *sc;
98 	uint32_t val;
99 
100 	sc = clknode_get_softc(clk);
101 
102 	if ((sc->flags & AW_CLK_HAS_GATE) == 0)
103 		return (0);
104 
105 	DEVICE_LOCK(clk);
106 	READ4(clk, sc->offset, &val);
107 	if (enable)
108 		val |= (1 << sc->gate_shift);
109 	else
110 		val &= ~(1 << sc->gate_shift);
111 	WRITE4(clk, sc->offset, val);
112 	DEVICE_UNLOCK(clk);
113 
114 	return (0);
115 }
116 
117 static int
aw_clk_m_set_mux(struct clknode * clk,int index)118 aw_clk_m_set_mux(struct clknode *clk, int index)
119 {
120 	struct aw_clk_m_sc *sc;
121 	uint32_t val;
122 
123 	sc = clknode_get_softc(clk);
124 
125 	if ((sc->flags & AW_CLK_HAS_MUX) == 0)
126 		return (0);
127 
128 	DEVICE_LOCK(clk);
129 	READ4(clk, sc->offset, &val);
130 	val &= ~sc->mux_mask;
131 	val |= index << sc->mux_shift;
132 	WRITE4(clk, sc->offset, val);
133 	DEVICE_UNLOCK(clk);
134 
135 	return (0);
136 }
137 
138 static uint64_t
aw_clk_m_find_best(struct aw_clk_m_sc * sc,uint64_t fparent,uint64_t * fout,uint32_t * factor_m)139 aw_clk_m_find_best(struct aw_clk_m_sc *sc, uint64_t fparent, uint64_t *fout,
140     uint32_t *factor_m)
141 {
142 	uint64_t cur, best;
143 	uint32_t m, max_m, min_m;
144 
145 	*factor_m = 0;
146 
147 	max_m = aw_clk_factor_get_max(&sc->m);
148 	min_m = aw_clk_factor_get_min(&sc->m);
149 
150 	for (m = min_m; m <= max_m; ) {
151 		cur = fparent / m;
152 		if (abs(*fout - cur) < abs(*fout - best)) {
153 			best = cur;
154 			*factor_m = m;
155 		}
156 		if ((sc->m.flags & AW_CLK_FACTOR_POWER_OF_TWO) != 0)
157 			m <<= 1;
158 		else
159 			m++;
160 	}
161 
162 	return (best);
163 }
164 
165 static int
aw_clk_m_set_freq(struct clknode * clk,uint64_t fparent,uint64_t * fout,int flags,int * stop)166 aw_clk_m_set_freq(struct clknode *clk, uint64_t fparent, uint64_t *fout,
167     int flags, int *stop)
168 {
169 	struct aw_clk_m_sc *sc;
170 	struct clknode *p_clk;
171 	uint64_t cur, best;
172 	uint32_t val, m, best_m;
173 
174 	sc = clknode_get_softc(clk);
175 
176 	best = cur = 0;
177 
178 	if ((sc->flags & AW_CLK_SET_PARENT) != 0) {
179 		p_clk = clknode_get_parent(clk);
180 		if (p_clk == NULL) {
181 			printf("%s: Cannot get parent for clock %s\n",
182 			    __func__,
183 			    clknode_get_name(clk));
184 			return (ENXIO);
185 		}
186 		clknode_set_freq(p_clk, *fout, CLK_SET_ROUND_MULTIPLE, 0);
187 		clknode_get_freq(p_clk, &fparent);
188 		best = aw_clk_m_find_best(sc, fparent, fout,
189 		    &best_m);
190 	} else {
191 		best = aw_clk_m_find_best(sc, fparent, fout,
192 		    &best_m);
193 	}
194 
195 	if ((flags & CLK_SET_DRYRUN) != 0) {
196 		*fout = best;
197 		*stop = 1;
198 		return (0);
199 	}
200 
201 	if ((best < *fout) &&
202 	  ((flags & CLK_SET_ROUND_DOWN) == 0)) {
203 		*stop = 1;
204 		return (ERANGE);
205 	}
206 	if ((best > *fout) &&
207 	  ((flags & CLK_SET_ROUND_UP) == 0)) {
208 		*stop = 1;
209 		return (ERANGE);
210 	}
211 
212 	DEVICE_LOCK(clk);
213 	READ4(clk, sc->offset, &val);
214 
215 	m = aw_clk_factor_get_value(&sc->m, best_m);
216 	val &= ~sc->m.mask;
217 	val |= m << sc->m.shift;
218 
219 	WRITE4(clk, sc->offset, val);
220 	DEVICE_UNLOCK(clk);
221 
222 	*fout = best;
223 	*stop = 1;
224 
225 	return (0);
226 }
227 
228 static int
aw_clk_m_recalc(struct clknode * clk,uint64_t * freq)229 aw_clk_m_recalc(struct clknode *clk, uint64_t *freq)
230 {
231 	struct aw_clk_m_sc *sc;
232 	uint32_t val, m;
233 
234 	sc = clknode_get_softc(clk);
235 
236 	DEVICE_LOCK(clk);
237 	READ4(clk, sc->offset, &val);
238 	DEVICE_UNLOCK(clk);
239 
240 	m = aw_clk_get_factor(val, &sc->m);
241 
242 	*freq = *freq / m;
243 
244 	return (0);
245 }
246 
247 static clknode_method_t aw_m_clknode_methods[] = {
248 	/* Device interface */
249 	CLKNODEMETHOD(clknode_init,		aw_clk_m_init),
250 	CLKNODEMETHOD(clknode_set_gate,		aw_clk_m_set_gate),
251 	CLKNODEMETHOD(clknode_set_mux,		aw_clk_m_set_mux),
252 	CLKNODEMETHOD(clknode_recalc_freq,	aw_clk_m_recalc),
253 	CLKNODEMETHOD(clknode_set_freq,		aw_clk_m_set_freq),
254 	CLKNODEMETHOD_END
255 };
256 
257 DEFINE_CLASS_1(aw_m_clknode, aw_m_clknode_class, aw_m_clknode_methods,
258     sizeof(struct aw_clk_m_sc), clknode_class);
259 
260 int
aw_clk_m_register(struct clkdom * clkdom,struct aw_clk_m_def * clkdef)261 aw_clk_m_register(struct clkdom *clkdom, struct aw_clk_m_def *clkdef)
262 {
263 	struct clknode *clk;
264 	struct aw_clk_m_sc *sc;
265 
266 	clk = clknode_create(clkdom, &aw_m_clknode_class, &clkdef->clkdef);
267 	if (clk == NULL)
268 		return (1);
269 
270 	sc = clknode_get_softc(clk);
271 
272 	sc->offset = clkdef->offset;
273 
274 	sc->m.shift = clkdef->m.shift;
275 	sc->m.width = clkdef->m.width;
276 	sc->m.mask = ((1 << sc->m.width) - 1) << sc->m.shift;
277 	sc->m.value = clkdef->m.value;
278 	sc->m.flags = clkdef->m.flags;
279 
280 	sc->mux_shift = clkdef->mux_shift;
281 	sc->mux_mask = ((1 << clkdef->mux_width) - 1) << sc->mux_shift;
282 
283 	sc->gate_shift = clkdef->gate_shift;
284 
285 	sc->flags = clkdef->flags;
286 
287 	clknode_register(clkdom, clk);
288 
289 	return (0);
290 }
291