1 /*-
2 * Copyright 2016 Michal Meloun <[email protected]>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29
30
31 #include <sys/param.h>
32 #include <sys/conf.h>
33 #include <sys/bus.h>
34 #include <sys/kernel.h>
35 #include <sys/systm.h>
36
37 #include <machine/bus.h>
38
39 #include <dev/extres/clk/clk_div.h>
40
41 #include "clkdev_if.h"
42
43 #define WR4(_clk, off, val) \
44 CLKDEV_WRITE_4(clknode_get_device(_clk), off, val)
45 #define RD4(_clk, off, val) \
46 CLKDEV_READ_4(clknode_get_device(_clk), off, val)
47 #define MD4(_clk, off, clr, set ) \
48 CLKDEV_MODIFY_4(clknode_get_device(_clk), off, clr, set)
49 #define DEVICE_LOCK(_clk) \
50 CLKDEV_DEVICE_LOCK(clknode_get_device(_clk))
51 #define DEVICE_UNLOCK(_clk) \
52 CLKDEV_DEVICE_UNLOCK(clknode_get_device(_clk))
53
54 static int clknode_div_init(struct clknode *clk, device_t dev);
55 static int clknode_div_recalc(struct clknode *clk, uint64_t *req);
56 static int clknode_div_set_freq(struct clknode *clknode, uint64_t fin,
57 uint64_t *fout, int flag, int *stop);
58
59 struct clknode_div_sc {
60 struct mtx *mtx;
61 struct resource *mem_res;
62 uint32_t offset;
63 uint32_t i_shift;
64 uint32_t i_mask;
65 uint32_t i_width;
66 uint32_t f_shift;
67 uint32_t f_mask;
68 uint32_t f_width;
69 int div_flags;
70 uint32_t divider; /* in natural form */
71
72 struct clk_div_table *div_table;
73 };
74
75 static clknode_method_t clknode_div_methods[] = {
76 /* Device interface */
77 CLKNODEMETHOD(clknode_init, clknode_div_init),
78 CLKNODEMETHOD(clknode_recalc_freq, clknode_div_recalc),
79 CLKNODEMETHOD(clknode_set_freq, clknode_div_set_freq),
80 CLKNODEMETHOD_END
81 };
82 DEFINE_CLASS_1(clknode_div, clknode_div_class, clknode_div_methods,
83 sizeof(struct clknode_div_sc), clknode_class);
84
85 static uint32_t
clknode_div_table_get_divider(struct clknode_div_sc * sc,uint32_t divider)86 clknode_div_table_get_divider(struct clknode_div_sc *sc, uint32_t divider)
87 {
88 struct clk_div_table *table;
89
90 if (!(sc->div_flags & CLK_DIV_WITH_TABLE))
91 return (divider);
92
93 for (table = sc->div_table; table->divider != 0; table++)
94 if (table->value == sc->divider)
95 return (table->divider);
96
97 return (0);
98 }
99
100 static int
clknode_div_table_get_value(struct clknode_div_sc * sc,uint32_t * divider)101 clknode_div_table_get_value(struct clknode_div_sc *sc, uint32_t *divider)
102 {
103 struct clk_div_table *table;
104
105 if (!(sc->div_flags & CLK_DIV_WITH_TABLE))
106 return (0);
107
108 for (table = sc->div_table; table->divider != 0; table++)
109 if (table->divider == *divider) {
110 *divider = table->value;
111 return (0);
112 }
113
114 return (ENOENT);
115 }
116
117 static int
clknode_div_init(struct clknode * clk,device_t dev)118 clknode_div_init(struct clknode *clk, device_t dev)
119 {
120 uint32_t reg;
121 struct clknode_div_sc *sc;
122 uint32_t i_div, f_div;
123 int rv;
124
125 sc = clknode_get_softc(clk);
126
127 DEVICE_LOCK(clk);
128 rv = RD4(clk, sc->offset, ®);
129 DEVICE_UNLOCK(clk);
130 if (rv != 0)
131 return (rv);
132
133 i_div = (reg >> sc->i_shift) & sc->i_mask;
134 if (!(sc->div_flags & CLK_DIV_ZERO_BASED))
135 i_div++;
136 f_div = (reg >> sc->f_shift) & sc->f_mask;
137 sc->divider = i_div << sc->f_width | f_div;
138
139 sc->divider = clknode_div_table_get_divider(sc, sc->divider);
140 if (sc->divider == 0)
141 panic("%s: divider is zero!\n", clknode_get_name(clk));
142
143 clknode_init_parent_idx(clk, 0);
144 return(0);
145 }
146
147 static int
clknode_div_recalc(struct clknode * clk,uint64_t * freq)148 clknode_div_recalc(struct clknode *clk, uint64_t *freq)
149 {
150 struct clknode_div_sc *sc;
151
152 sc = clknode_get_softc(clk);
153 if (sc->divider == 0) {
154 printf("%s: %s divider is zero!\n", clknode_get_name(clk),
155 __func__);
156 *freq = 0;
157 return(EINVAL);
158 }
159 *freq = (*freq << sc->f_width) / sc->divider;
160 return (0);
161 }
162
163 static int
clknode_div_set_freq(struct clknode * clk,uint64_t fin,uint64_t * fout,int flags,int * stop)164 clknode_div_set_freq(struct clknode *clk, uint64_t fin, uint64_t *fout,
165 int flags, int *stop)
166 {
167 struct clknode_div_sc *sc;
168 uint64_t divider, _fin, _fout;
169 uint32_t div_value, reg, i_div, f_div, hw_i_div;
170 int rv;
171
172 sc = clknode_get_softc(clk);
173
174 /* For fractional divider. */
175 _fin = fin << sc->f_width;
176 divider = (_fin + *fout / 2) / *fout;
177 _fout = _fin / divider;
178
179 /* Rounding. */
180 if ((flags & CLK_SET_ROUND_UP) && (*fout < _fout))
181 divider--;
182 else if ((flags & CLK_SET_ROUND_DOWN) && (*fout > _fout))
183 divider++;
184
185 /* Break divider into integer and fractional parts. */
186 i_div = divider >> sc->f_width;
187 f_div = divider & sc->f_mask;
188
189 if (i_div == 0) {
190 printf("%s: %s integer divider is zero!\n",
191 clknode_get_name(clk), __func__);
192 return(EINVAL);
193 }
194
195 hw_i_div = i_div;
196 if (!(sc->div_flags & CLK_DIV_ZERO_BASED))
197 hw_i_div--;
198
199 *stop = 1;
200 if (hw_i_div > sc->i_mask &&
201 ((sc->div_flags & CLK_DIV_WITH_TABLE) == 0)) {
202 /* XXX Or only return error? */
203 printf("%s: %s integer divider is too big: %u\n",
204 clknode_get_name(clk), __func__, hw_i_div);
205 hw_i_div = sc->i_mask;
206 *stop = 0;
207 }
208
209 i_div = hw_i_div;
210 if (!(sc->div_flags & CLK_DIV_ZERO_BASED))
211 i_div++;
212 divider = i_div << sc->f_width | f_div;
213
214 if ((flags & CLK_SET_DRYRUN) == 0) {
215 if ((*stop != 0) &&
216 ((flags & (CLK_SET_ROUND_UP | CLK_SET_ROUND_DOWN)) == 0) &&
217 (*fout != (_fin / divider)))
218 return (ERANGE);
219
220 div_value = divider;
221 if (clknode_div_table_get_value(sc, &div_value) != 0)
222 return (ERANGE);
223 if (div_value != divider)
224 i_div = div_value;
225
226 DEVICE_LOCK(clk);
227 rv = MD4(clk, sc->offset,
228 (sc->i_mask << sc->i_shift) | (sc->f_mask << sc->f_shift),
229 (i_div << sc->i_shift) | (f_div << sc->f_shift));
230 if (rv != 0) {
231 DEVICE_UNLOCK(clk);
232 return (rv);
233 }
234 RD4(clk, sc->offset, ®);
235 DEVICE_UNLOCK(clk);
236
237 sc->divider = divider;
238 }
239
240 *fout = _fin / divider;
241 return (0);
242 }
243
244 int
clknode_div_register(struct clkdom * clkdom,struct clk_div_def * clkdef)245 clknode_div_register(struct clkdom *clkdom, struct clk_div_def *clkdef)
246 {
247 struct clknode *clk;
248 struct clknode_div_sc *sc;
249
250 clk = clknode_create(clkdom, &clknode_div_class, &clkdef->clkdef);
251 if (clk == NULL)
252 return (1);
253
254 sc = clknode_get_softc(clk);
255 sc->offset = clkdef->offset;
256 sc->i_shift = clkdef->i_shift;
257 sc->i_width = clkdef->i_width;
258 sc->i_mask = (1 << clkdef->i_width) - 1;
259 sc->f_shift = clkdef->f_shift;
260 sc->f_width = clkdef->f_width;
261 sc->f_mask = (1 << clkdef->f_width) - 1;
262 sc->div_flags = clkdef->div_flags;
263 sc->div_table = clkdef->div_table;
264
265 clknode_register(clkdom, clk);
266 return (0);
267 }
268