xref: /openbmc/linux/drivers/clk/sunxi/clk-sunxi.c (revision cd5d5810)
1 /*
2  * Copyright 2013 Emilio López
3  *
4  * Emilio López <emilio@elopez.com.ar>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 #include <linux/clk-provider.h>
18 #include <linux/clkdev.h>
19 #include <linux/clk/sunxi.h>
20 #include <linux/of.h>
21 #include <linux/of_address.h>
22 
23 #include "clk-factors.h"
24 
25 static DEFINE_SPINLOCK(clk_lock);
26 
27 /**
28  * sun4i_osc_clk_setup() - Setup function for gatable oscillator
29  */
30 
31 #define SUNXI_OSC24M_GATE	0
32 
33 static void __init sun4i_osc_clk_setup(struct device_node *node)
34 {
35 	struct clk *clk;
36 	struct clk_fixed_rate *fixed;
37 	struct clk_gate *gate;
38 	const char *clk_name = node->name;
39 	u32 rate;
40 
41 	/* allocate fixed-rate and gate clock structs */
42 	fixed = kzalloc(sizeof(struct clk_fixed_rate), GFP_KERNEL);
43 	if (!fixed)
44 		return;
45 	gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL);
46 	if (!gate) {
47 		kfree(fixed);
48 		return;
49 	}
50 
51 	if (of_property_read_u32(node, "clock-frequency", &rate))
52 		return;
53 
54 	/* set up gate and fixed rate properties */
55 	gate->reg = of_iomap(node, 0);
56 	gate->bit_idx = SUNXI_OSC24M_GATE;
57 	gate->lock = &clk_lock;
58 	fixed->fixed_rate = rate;
59 
60 	clk = clk_register_composite(NULL, clk_name,
61 			NULL, 0,
62 			NULL, NULL,
63 			&fixed->hw, &clk_fixed_rate_ops,
64 			&gate->hw, &clk_gate_ops,
65 			CLK_IS_ROOT);
66 
67 	if (!IS_ERR(clk)) {
68 		of_clk_add_provider(node, of_clk_src_simple_get, clk);
69 		clk_register_clkdev(clk, clk_name, NULL);
70 	}
71 }
72 CLK_OF_DECLARE(sun4i_osc, "allwinner,sun4i-osc-clk", sun4i_osc_clk_setup);
73 
74 
75 
76 /**
77  * sun4i_get_pll1_factors() - calculates n, k, m, p factors for PLL1
78  * PLL1 rate is calculated as follows
79  * rate = (parent_rate * n * (k + 1) >> p) / (m + 1);
80  * parent_rate is always 24Mhz
81  */
82 
83 static void sun4i_get_pll1_factors(u32 *freq, u32 parent_rate,
84 				   u8 *n, u8 *k, u8 *m, u8 *p)
85 {
86 	u8 div;
87 
88 	/* Normalize value to a 6M multiple */
89 	div = *freq / 6000000;
90 	*freq = 6000000 * div;
91 
92 	/* we were called to round the frequency, we can now return */
93 	if (n == NULL)
94 		return;
95 
96 	/* m is always zero for pll1 */
97 	*m = 0;
98 
99 	/* k is 1 only on these cases */
100 	if (*freq >= 768000000 || *freq == 42000000 || *freq == 54000000)
101 		*k = 1;
102 	else
103 		*k = 0;
104 
105 	/* p will be 3 for divs under 10 */
106 	if (div < 10)
107 		*p = 3;
108 
109 	/* p will be 2 for divs between 10 - 20 and odd divs under 32 */
110 	else if (div < 20 || (div < 32 && (div & 1)))
111 		*p = 2;
112 
113 	/* p will be 1 for even divs under 32, divs under 40 and odd pairs
114 	 * of divs between 40-62 */
115 	else if (div < 40 || (div < 64 && (div & 2)))
116 		*p = 1;
117 
118 	/* any other entries have p = 0 */
119 	else
120 		*p = 0;
121 
122 	/* calculate a suitable n based on k and p */
123 	div <<= *p;
124 	div /= (*k + 1);
125 	*n = div / 4;
126 }
127 
128 /**
129  * sun6i_a31_get_pll1_factors() - calculates n, k and m factors for PLL1
130  * PLL1 rate is calculated as follows
131  * rate = parent_rate * (n + 1) * (k + 1) / (m + 1);
132  * parent_rate should always be 24MHz
133  */
134 static void sun6i_a31_get_pll1_factors(u32 *freq, u32 parent_rate,
135 				       u8 *n, u8 *k, u8 *m, u8 *p)
136 {
137 	/*
138 	 * We can operate only on MHz, this will make our life easier
139 	 * later.
140 	 */
141 	u32 freq_mhz = *freq / 1000000;
142 	u32 parent_freq_mhz = parent_rate / 1000000;
143 
144 	/*
145 	 * Round down the frequency to the closest multiple of either
146 	 * 6 or 16
147 	 */
148 	u32 round_freq_6 = round_down(freq_mhz, 6);
149 	u32 round_freq_16 = round_down(freq_mhz, 16);
150 
151 	if (round_freq_6 > round_freq_16)
152 		freq_mhz = round_freq_6;
153 	else
154 		freq_mhz = round_freq_16;
155 
156 	*freq = freq_mhz * 1000000;
157 
158 	/*
159 	 * If the factors pointer are null, we were just called to
160 	 * round down the frequency.
161 	 * Exit.
162 	 */
163 	if (n == NULL)
164 		return;
165 
166 	/* If the frequency is a multiple of 32 MHz, k is always 3 */
167 	if (!(freq_mhz % 32))
168 		*k = 3;
169 	/* If the frequency is a multiple of 9 MHz, k is always 2 */
170 	else if (!(freq_mhz % 9))
171 		*k = 2;
172 	/* If the frequency is a multiple of 8 MHz, k is always 1 */
173 	else if (!(freq_mhz % 8))
174 		*k = 1;
175 	/* Otherwise, we don't use the k factor */
176 	else
177 		*k = 0;
178 
179 	/*
180 	 * If the frequency is a multiple of 2 but not a multiple of
181 	 * 3, m is 3. This is the first time we use 6 here, yet we
182 	 * will use it on several other places.
183 	 * We use this number because it's the lowest frequency we can
184 	 * generate (with n = 0, k = 0, m = 3), so every other frequency
185 	 * somehow relates to this frequency.
186 	 */
187 	if ((freq_mhz % 6) == 2 || (freq_mhz % 6) == 4)
188 		*m = 2;
189 	/*
190 	 * If the frequency is a multiple of 6MHz, but the factor is
191 	 * odd, m will be 3
192 	 */
193 	else if ((freq_mhz / 6) & 1)
194 		*m = 3;
195 	/* Otherwise, we end up with m = 1 */
196 	else
197 		*m = 1;
198 
199 	/* Calculate n thanks to the above factors we already got */
200 	*n = freq_mhz * (*m + 1) / ((*k + 1) * parent_freq_mhz) - 1;
201 
202 	/*
203 	 * If n end up being outbound, and that we can still decrease
204 	 * m, do it.
205 	 */
206 	if ((*n + 1) > 31 && (*m + 1) > 1) {
207 		*n = (*n + 1) / 2 - 1;
208 		*m = (*m + 1) / 2 - 1;
209 	}
210 }
211 
212 /**
213  * sun4i_get_apb1_factors() - calculates m, p factors for APB1
214  * APB1 rate is calculated as follows
215  * rate = (parent_rate >> p) / (m + 1);
216  */
217 
218 static void sun4i_get_apb1_factors(u32 *freq, u32 parent_rate,
219 				   u8 *n, u8 *k, u8 *m, u8 *p)
220 {
221 	u8 calcm, calcp;
222 
223 	if (parent_rate < *freq)
224 		*freq = parent_rate;
225 
226 	parent_rate = (parent_rate + (*freq - 1)) / *freq;
227 
228 	/* Invalid rate! */
229 	if (parent_rate > 32)
230 		return;
231 
232 	if (parent_rate <= 4)
233 		calcp = 0;
234 	else if (parent_rate <= 8)
235 		calcp = 1;
236 	else if (parent_rate <= 16)
237 		calcp = 2;
238 	else
239 		calcp = 3;
240 
241 	calcm = (parent_rate >> calcp) - 1;
242 
243 	*freq = (parent_rate >> calcp) / (calcm + 1);
244 
245 	/* we were called to round the frequency, we can now return */
246 	if (n == NULL)
247 		return;
248 
249 	*m = calcm;
250 	*p = calcp;
251 }
252 
253 
254 
255 /**
256  * sunxi_factors_clk_setup() - Setup function for factor clocks
257  */
258 
259 struct factors_data {
260 	struct clk_factors_config *table;
261 	void (*getter) (u32 *rate, u32 parent_rate, u8 *n, u8 *k, u8 *m, u8 *p);
262 };
263 
264 static struct clk_factors_config sun4i_pll1_config = {
265 	.nshift = 8,
266 	.nwidth = 5,
267 	.kshift = 4,
268 	.kwidth = 2,
269 	.mshift = 0,
270 	.mwidth = 2,
271 	.pshift = 16,
272 	.pwidth = 2,
273 };
274 
275 static struct clk_factors_config sun6i_a31_pll1_config = {
276 	.nshift	= 8,
277 	.nwidth = 5,
278 	.kshift = 4,
279 	.kwidth = 2,
280 	.mshift = 0,
281 	.mwidth = 2,
282 };
283 
284 static struct clk_factors_config sun4i_apb1_config = {
285 	.mshift = 0,
286 	.mwidth = 5,
287 	.pshift = 16,
288 	.pwidth = 2,
289 };
290 
291 static const struct factors_data sun4i_pll1_data __initconst = {
292 	.table = &sun4i_pll1_config,
293 	.getter = sun4i_get_pll1_factors,
294 };
295 
296 static const struct factors_data sun6i_a31_pll1_data __initconst = {
297 	.table = &sun6i_a31_pll1_config,
298 	.getter = sun6i_a31_get_pll1_factors,
299 };
300 
301 static const struct factors_data sun4i_apb1_data __initconst = {
302 	.table = &sun4i_apb1_config,
303 	.getter = sun4i_get_apb1_factors,
304 };
305 
306 static void __init sunxi_factors_clk_setup(struct device_node *node,
307 					   struct factors_data *data)
308 {
309 	struct clk *clk;
310 	const char *clk_name = node->name;
311 	const char *parent;
312 	void *reg;
313 
314 	reg = of_iomap(node, 0);
315 
316 	parent = of_clk_get_parent_name(node, 0);
317 
318 	clk = clk_register_factors(NULL, clk_name, parent, 0, reg,
319 				   data->table, data->getter, &clk_lock);
320 
321 	if (!IS_ERR(clk)) {
322 		of_clk_add_provider(node, of_clk_src_simple_get, clk);
323 		clk_register_clkdev(clk, clk_name, NULL);
324 	}
325 }
326 
327 
328 
329 /**
330  * sunxi_mux_clk_setup() - Setup function for muxes
331  */
332 
333 #define SUNXI_MUX_GATE_WIDTH	2
334 
335 struct mux_data {
336 	u8 shift;
337 };
338 
339 static const struct mux_data sun4i_cpu_mux_data __initconst = {
340 	.shift = 16,
341 };
342 
343 static const struct mux_data sun6i_a31_ahb1_mux_data __initconst = {
344 	.shift = 12,
345 };
346 
347 static const struct mux_data sun4i_apb1_mux_data __initconst = {
348 	.shift = 24,
349 };
350 
351 static void __init sunxi_mux_clk_setup(struct device_node *node,
352 				       struct mux_data *data)
353 {
354 	struct clk *clk;
355 	const char *clk_name = node->name;
356 	const char *parents[5];
357 	void *reg;
358 	int i = 0;
359 
360 	reg = of_iomap(node, 0);
361 
362 	while (i < 5 && (parents[i] = of_clk_get_parent_name(node, i)) != NULL)
363 		i++;
364 
365 	clk = clk_register_mux(NULL, clk_name, parents, i,
366 			       CLK_SET_RATE_NO_REPARENT, reg,
367 			       data->shift, SUNXI_MUX_GATE_WIDTH,
368 			       0, &clk_lock);
369 
370 	if (clk) {
371 		of_clk_add_provider(node, of_clk_src_simple_get, clk);
372 		clk_register_clkdev(clk, clk_name, NULL);
373 	}
374 }
375 
376 
377 
378 /**
379  * sunxi_divider_clk_setup() - Setup function for simple divider clocks
380  */
381 
382 struct div_data {
383 	u8	shift;
384 	u8	pow;
385 	u8	width;
386 };
387 
388 static const struct div_data sun4i_axi_data __initconst = {
389 	.shift	= 0,
390 	.pow	= 0,
391 	.width	= 2,
392 };
393 
394 static const struct div_data sun4i_ahb_data __initconst = {
395 	.shift	= 4,
396 	.pow	= 1,
397 	.width	= 2,
398 };
399 
400 static const struct div_data sun4i_apb0_data __initconst = {
401 	.shift	= 8,
402 	.pow	= 1,
403 	.width	= 2,
404 };
405 
406 static const struct div_data sun6i_a31_apb2_div_data __initconst = {
407 	.shift	= 0,
408 	.pow	= 0,
409 	.width	= 4,
410 };
411 
412 static void __init sunxi_divider_clk_setup(struct device_node *node,
413 					   struct div_data *data)
414 {
415 	struct clk *clk;
416 	const char *clk_name = node->name;
417 	const char *clk_parent;
418 	void *reg;
419 
420 	reg = of_iomap(node, 0);
421 
422 	clk_parent = of_clk_get_parent_name(node, 0);
423 
424 	clk = clk_register_divider(NULL, clk_name, clk_parent, 0,
425 				   reg, data->shift, data->width,
426 				   data->pow ? CLK_DIVIDER_POWER_OF_TWO : 0,
427 				   &clk_lock);
428 	if (clk) {
429 		of_clk_add_provider(node, of_clk_src_simple_get, clk);
430 		clk_register_clkdev(clk, clk_name, NULL);
431 	}
432 }
433 
434 
435 
436 /**
437  * sunxi_gates_clk_setup() - Setup function for leaf gates on clocks
438  */
439 
440 #define SUNXI_GATES_MAX_SIZE	64
441 
442 struct gates_data {
443 	DECLARE_BITMAP(mask, SUNXI_GATES_MAX_SIZE);
444 };
445 
446 static const struct gates_data sun4i_axi_gates_data __initconst = {
447 	.mask = {1},
448 };
449 
450 static const struct gates_data sun4i_ahb_gates_data __initconst = {
451 	.mask = {0x7F77FFF, 0x14FB3F},
452 };
453 
454 static const struct gates_data sun5i_a10s_ahb_gates_data __initconst = {
455 	.mask = {0x147667e7, 0x185915},
456 };
457 
458 static const struct gates_data sun5i_a13_ahb_gates_data __initconst = {
459 	.mask = {0x107067e7, 0x185111},
460 };
461 
462 static const struct gates_data sun6i_a31_ahb1_gates_data __initconst = {
463 	.mask = {0xEDFE7F62, 0x794F931},
464 };
465 
466 static const struct gates_data sun7i_a20_ahb_gates_data __initconst = {
467 	.mask = { 0x12f77fff, 0x16ff3f },
468 };
469 
470 static const struct gates_data sun4i_apb0_gates_data __initconst = {
471 	.mask = {0x4EF},
472 };
473 
474 static const struct gates_data sun5i_a10s_apb0_gates_data __initconst = {
475 	.mask = {0x469},
476 };
477 
478 static const struct gates_data sun5i_a13_apb0_gates_data __initconst = {
479 	.mask = {0x61},
480 };
481 
482 static const struct gates_data sun7i_a20_apb0_gates_data __initconst = {
483 	.mask = { 0x4ff },
484 };
485 
486 static const struct gates_data sun4i_apb1_gates_data __initconst = {
487 	.mask = {0xFF00F7},
488 };
489 
490 static const struct gates_data sun5i_a10s_apb1_gates_data __initconst = {
491 	.mask = {0xf0007},
492 };
493 
494 static const struct gates_data sun5i_a13_apb1_gates_data __initconst = {
495 	.mask = {0xa0007},
496 };
497 
498 static const struct gates_data sun6i_a31_apb1_gates_data __initconst = {
499 	.mask = {0x3031},
500 };
501 
502 static const struct gates_data sun6i_a31_apb2_gates_data __initconst = {
503 	.mask = {0x3F000F},
504 };
505 
506 static const struct gates_data sun7i_a20_apb1_gates_data __initconst = {
507 	.mask = { 0xff80ff },
508 };
509 
510 static void __init sunxi_gates_clk_setup(struct device_node *node,
511 					 struct gates_data *data)
512 {
513 	struct clk_onecell_data *clk_data;
514 	const char *clk_parent;
515 	const char *clk_name;
516 	void *reg;
517 	int qty;
518 	int i = 0;
519 	int j = 0;
520 	int ignore;
521 
522 	reg = of_iomap(node, 0);
523 
524 	clk_parent = of_clk_get_parent_name(node, 0);
525 
526 	/* Worst-case size approximation and memory allocation */
527 	qty = find_last_bit(data->mask, SUNXI_GATES_MAX_SIZE);
528 	clk_data = kmalloc(sizeof(struct clk_onecell_data), GFP_KERNEL);
529 	if (!clk_data)
530 		return;
531 	clk_data->clks = kzalloc((qty+1) * sizeof(struct clk *), GFP_KERNEL);
532 	if (!clk_data->clks) {
533 		kfree(clk_data);
534 		return;
535 	}
536 
537 	for_each_set_bit(i, data->mask, SUNXI_GATES_MAX_SIZE) {
538 		of_property_read_string_index(node, "clock-output-names",
539 					      j, &clk_name);
540 
541 		/* No driver claims this clock, but it should remain gated */
542 		ignore = !strcmp("ahb_sdram", clk_name) ? CLK_IGNORE_UNUSED : 0;
543 
544 		clk_data->clks[i] = clk_register_gate(NULL, clk_name,
545 						      clk_parent, ignore,
546 						      reg + 4 * (i/32), i % 32,
547 						      0, &clk_lock);
548 		WARN_ON(IS_ERR(clk_data->clks[i]));
549 
550 		j++;
551 	}
552 
553 	/* Adjust to the real max */
554 	clk_data->clk_num = i;
555 
556 	of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
557 }
558 
559 /* Matches for factors clocks */
560 static const struct of_device_id clk_factors_match[] __initconst = {
561 	{.compatible = "allwinner,sun4i-pll1-clk", .data = &sun4i_pll1_data,},
562 	{.compatible = "allwinner,sun6i-a31-pll1-clk", .data = &sun6i_a31_pll1_data,},
563 	{.compatible = "allwinner,sun4i-apb1-clk", .data = &sun4i_apb1_data,},
564 	{}
565 };
566 
567 /* Matches for divider clocks */
568 static const struct of_device_id clk_div_match[] __initconst = {
569 	{.compatible = "allwinner,sun4i-axi-clk", .data = &sun4i_axi_data,},
570 	{.compatible = "allwinner,sun4i-ahb-clk", .data = &sun4i_ahb_data,},
571 	{.compatible = "allwinner,sun4i-apb0-clk", .data = &sun4i_apb0_data,},
572 	{.compatible = "allwinner,sun6i-a31-apb2-div-clk", .data = &sun6i_a31_apb2_div_data,},
573 	{}
574 };
575 
576 /* Matches for mux clocks */
577 static const struct of_device_id clk_mux_match[] __initconst = {
578 	{.compatible = "allwinner,sun4i-cpu-clk", .data = &sun4i_cpu_mux_data,},
579 	{.compatible = "allwinner,sun4i-apb1-mux-clk", .data = &sun4i_apb1_mux_data,},
580 	{.compatible = "allwinner,sun6i-a31-ahb1-mux-clk", .data = &sun6i_a31_ahb1_mux_data,},
581 	{}
582 };
583 
584 /* Matches for gate clocks */
585 static const struct of_device_id clk_gates_match[] __initconst = {
586 	{.compatible = "allwinner,sun4i-axi-gates-clk", .data = &sun4i_axi_gates_data,},
587 	{.compatible = "allwinner,sun4i-ahb-gates-clk", .data = &sun4i_ahb_gates_data,},
588 	{.compatible = "allwinner,sun5i-a10s-ahb-gates-clk", .data = &sun5i_a10s_ahb_gates_data,},
589 	{.compatible = "allwinner,sun5i-a13-ahb-gates-clk", .data = &sun5i_a13_ahb_gates_data,},
590 	{.compatible = "allwinner,sun6i-a31-ahb1-gates-clk", .data = &sun6i_a31_ahb1_gates_data,},
591 	{.compatible = "allwinner,sun7i-a20-ahb-gates-clk", .data = &sun7i_a20_ahb_gates_data,},
592 	{.compatible = "allwinner,sun4i-apb0-gates-clk", .data = &sun4i_apb0_gates_data,},
593 	{.compatible = "allwinner,sun5i-a10s-apb0-gates-clk", .data = &sun5i_a10s_apb0_gates_data,},
594 	{.compatible = "allwinner,sun5i-a13-apb0-gates-clk", .data = &sun5i_a13_apb0_gates_data,},
595 	{.compatible = "allwinner,sun7i-a20-apb0-gates-clk", .data = &sun7i_a20_apb0_gates_data,},
596 	{.compatible = "allwinner,sun4i-apb1-gates-clk", .data = &sun4i_apb1_gates_data,},
597 	{.compatible = "allwinner,sun5i-a10s-apb1-gates-clk", .data = &sun5i_a10s_apb1_gates_data,},
598 	{.compatible = "allwinner,sun5i-a13-apb1-gates-clk", .data = &sun5i_a13_apb1_gates_data,},
599 	{.compatible = "allwinner,sun6i-a31-apb1-gates-clk", .data = &sun6i_a31_apb1_gates_data,},
600 	{.compatible = "allwinner,sun7i-a20-apb1-gates-clk", .data = &sun7i_a20_apb1_gates_data,},
601 	{.compatible = "allwinner,sun6i-a31-apb2-gates-clk", .data = &sun6i_a31_apb2_gates_data,},
602 	{}
603 };
604 
605 static void __init of_sunxi_table_clock_setup(const struct of_device_id *clk_match,
606 					      void *function)
607 {
608 	struct device_node *np;
609 	const struct div_data *data;
610 	const struct of_device_id *match;
611 	void (*setup_function)(struct device_node *, const void *) = function;
612 
613 	for_each_matching_node(np, clk_match) {
614 		match = of_match_node(clk_match, np);
615 		data = match->data;
616 		setup_function(np, data);
617 	}
618 }
619 
620 void __init sunxi_init_clocks(void)
621 {
622 	/* Register all the simple and basic clocks on DT */
623 	of_clk_init(NULL);
624 
625 	/* Register factor clocks */
626 	of_sunxi_table_clock_setup(clk_factors_match, sunxi_factors_clk_setup);
627 
628 	/* Register divider clocks */
629 	of_sunxi_table_clock_setup(clk_div_match, sunxi_divider_clk_setup);
630 
631 	/* Register mux clocks */
632 	of_sunxi_table_clock_setup(clk_mux_match, sunxi_mux_clk_setup);
633 
634 	/* Register gate clocks */
635 	of_sunxi_table_clock_setup(clk_gates_match, sunxi_gates_clk_setup);
636 }
637