xref: /openbmc/u-boot/drivers/clk/clk_zynq.c (revision 2399e401)
1 /*
2  * Copyright (C) 2017 Weidmüller Interface GmbH & Co. KG
3  * Stefan Herbrechtsmeier <stefan.herbrechtsmeier@weidmueller.com>
4  *
5  * Copyright (C) 2013 Soren Brinkmann <soren.brinkmann@xilinx.com>
6  * Copyright (C) 2013 Xilinx, Inc. All rights reserved.
7  *
8  * SPDX-License-Identifier:	GPL-2.0+
9  */
10 
11 #include <common.h>
12 #include <clk-uclass.h>
13 #include <dm.h>
14 #include <dm/lists.h>
15 #include <errno.h>
16 #include <asm/io.h>
17 #include <asm/arch/clk.h>
18 #include <asm/arch/hardware.h>
19 #include <asm/arch/sys_proto.h>
20 
21 /* Register bitfield defines */
22 #define PLLCTRL_FBDIV_MASK	0x7f000
23 #define PLLCTRL_FBDIV_SHIFT	12
24 #define PLLCTRL_BPFORCE_MASK	(1 << 4)
25 #define PLLCTRL_PWRDWN_MASK	2
26 #define PLLCTRL_PWRDWN_SHIFT	1
27 #define PLLCTRL_RESET_MASK	1
28 #define PLLCTRL_RESET_SHIFT	0
29 
30 #define ZYNQ_CLK_MAXDIV		0x3f
31 #define CLK_CTRL_DIV1_SHIFT	20
32 #define CLK_CTRL_DIV1_MASK	(ZYNQ_CLK_MAXDIV << CLK_CTRL_DIV1_SHIFT)
33 #define CLK_CTRL_DIV0_SHIFT	8
34 #define CLK_CTRL_DIV0_MASK	(ZYNQ_CLK_MAXDIV << CLK_CTRL_DIV0_SHIFT)
35 #define CLK_CTRL_SRCSEL_SHIFT	4
36 #define CLK_CTRL_SRCSEL_MASK	(0x3 << CLK_CTRL_SRCSEL_SHIFT)
37 
38 #define CLK_CTRL_DIV2X_SHIFT	26
39 #define CLK_CTRL_DIV2X_MASK	(ZYNQ_CLK_MAXDIV << CLK_CTRL_DIV2X_SHIFT)
40 #define CLK_CTRL_DIV3X_SHIFT	20
41 #define CLK_CTRL_DIV3X_MASK	(ZYNQ_CLK_MAXDIV << CLK_CTRL_DIV3X_SHIFT)
42 
43 DECLARE_GLOBAL_DATA_PTR;
44 
45 #ifndef CONFIG_SPL_BUILD
46 enum zynq_clk_rclk {mio_clk, emio_clk};
47 #endif
48 
49 struct zynq_clk_priv {
50 	ulong ps_clk_freq;
51 #ifndef CONFIG_SPL_BUILD
52 	struct clk gem_emio_clk[2];
53 #endif
54 };
55 
56 static void *zynq_clk_get_register(enum zynq_clk id)
57 {
58 	switch (id) {
59 	case armpll_clk:
60 		return &slcr_base->arm_pll_ctrl;
61 	case ddrpll_clk:
62 		return &slcr_base->ddr_pll_ctrl;
63 	case iopll_clk:
64 		return &slcr_base->io_pll_ctrl;
65 	case lqspi_clk:
66 		return &slcr_base->lqspi_clk_ctrl;
67 	case smc_clk:
68 		return &slcr_base->smc_clk_ctrl;
69 	case pcap_clk:
70 		return &slcr_base->pcap_clk_ctrl;
71 	case sdio0_clk ... sdio1_clk:
72 		return &slcr_base->sdio_clk_ctrl;
73 	case uart0_clk ... uart1_clk:
74 		return &slcr_base->uart_clk_ctrl;
75 	case spi0_clk ... spi1_clk:
76 		return &slcr_base->spi_clk_ctrl;
77 #ifndef CONFIG_SPL_BUILD
78 	case dci_clk:
79 		return &slcr_base->dci_clk_ctrl;
80 	case gem0_clk:
81 		return &slcr_base->gem0_clk_ctrl;
82 	case gem1_clk:
83 		return &slcr_base->gem1_clk_ctrl;
84 	case fclk0_clk:
85 		return &slcr_base->fpga0_clk_ctrl;
86 	case fclk1_clk:
87 		return &slcr_base->fpga1_clk_ctrl;
88 	case fclk2_clk:
89 		return &slcr_base->fpga2_clk_ctrl;
90 	case fclk3_clk:
91 		return &slcr_base->fpga3_clk_ctrl;
92 	case can0_clk ... can1_clk:
93 		return &slcr_base->can_clk_ctrl;
94 	case dbg_trc_clk ... dbg_apb_clk:
95 		/* fall through */
96 #endif
97 	default:
98 		return &slcr_base->dbg_clk_ctrl;
99 	}
100 }
101 
102 static enum zynq_clk zynq_clk_get_cpu_pll(u32 clk_ctrl)
103 {
104 	u32 srcsel = (clk_ctrl & CLK_CTRL_SRCSEL_MASK) >> CLK_CTRL_SRCSEL_SHIFT;
105 
106 	switch (srcsel) {
107 	case 2:
108 		return ddrpll_clk;
109 	case 3:
110 		return iopll_clk;
111 	case 0 ... 1:
112 	default:
113 		return armpll_clk;
114 	}
115 }
116 
117 static enum zynq_clk zynq_clk_get_peripheral_pll(u32 clk_ctrl)
118 {
119 	u32 srcsel = (clk_ctrl & CLK_CTRL_SRCSEL_MASK) >> CLK_CTRL_SRCSEL_SHIFT;
120 
121 	switch (srcsel) {
122 	case 2:
123 		return armpll_clk;
124 	case 3:
125 		return ddrpll_clk;
126 	case 0 ... 1:
127 	default:
128 		return iopll_clk;
129 	}
130 }
131 
132 static ulong zynq_clk_get_pll_rate(struct zynq_clk_priv *priv, enum zynq_clk id)
133 {
134 	u32 clk_ctrl, reset, pwrdwn, mul, bypass;
135 
136 	clk_ctrl = readl(zynq_clk_get_register(id));
137 
138 	reset = (clk_ctrl & PLLCTRL_RESET_MASK) >> PLLCTRL_RESET_SHIFT;
139 	pwrdwn = (clk_ctrl & PLLCTRL_PWRDWN_MASK) >> PLLCTRL_PWRDWN_SHIFT;
140 	if (reset || pwrdwn)
141 		return 0;
142 
143 	bypass = clk_ctrl & PLLCTRL_BPFORCE_MASK;
144 	if (bypass)
145 		mul = 1;
146 	else
147 		mul = (clk_ctrl & PLLCTRL_FBDIV_MASK) >> PLLCTRL_FBDIV_SHIFT;
148 
149 	return priv->ps_clk_freq * mul;
150 }
151 
152 #ifndef CONFIG_SPL_BUILD
153 static enum zynq_clk_rclk zynq_clk_get_gem_rclk(enum zynq_clk id)
154 {
155 	u32 clk_ctrl, srcsel;
156 
157 	if (id == gem0_clk)
158 		clk_ctrl = readl(&slcr_base->gem0_rclk_ctrl);
159 	else
160 		clk_ctrl = readl(&slcr_base->gem1_rclk_ctrl);
161 
162 	srcsel = (clk_ctrl & CLK_CTRL_SRCSEL_MASK) >> CLK_CTRL_SRCSEL_SHIFT;
163 	if (srcsel)
164 		return emio_clk;
165 	else
166 		return mio_clk;
167 }
168 #endif
169 
170 static ulong zynq_clk_get_cpu_rate(struct zynq_clk_priv *priv, enum zynq_clk id)
171 {
172 	u32 clk_621, clk_ctrl, div;
173 	enum zynq_clk pll;
174 
175 	clk_ctrl = readl(&slcr_base->arm_clk_ctrl);
176 
177 	div = (clk_ctrl & CLK_CTRL_DIV0_MASK) >> CLK_CTRL_DIV0_SHIFT;
178 
179 	switch (id) {
180 	case cpu_1x_clk:
181 		div *= 2;
182 		/* fall through */
183 	case cpu_2x_clk:
184 		clk_621 = readl(&slcr_base->clk_621_true) & 1;
185 		div *= 2 + clk_621;
186 		break;
187 	case cpu_3or2x_clk:
188 		div *= 2;
189 		/* fall through */
190 	case cpu_6or4x_clk:
191 		break;
192 	default:
193 		return 0;
194 	}
195 
196 	pll = zynq_clk_get_cpu_pll(clk_ctrl);
197 
198 	return DIV_ROUND_CLOSEST(zynq_clk_get_pll_rate(priv, pll), div);
199 }
200 
201 #ifndef CONFIG_SPL_BUILD
202 static ulong zynq_clk_get_ddr2x_rate(struct zynq_clk_priv *priv)
203 {
204 	u32 clk_ctrl, div;
205 
206 	clk_ctrl = readl(&slcr_base->ddr_clk_ctrl);
207 
208 	div = (clk_ctrl & CLK_CTRL_DIV2X_MASK) >> CLK_CTRL_DIV2X_SHIFT;
209 
210 	return DIV_ROUND_CLOSEST(zynq_clk_get_pll_rate(priv, ddrpll_clk), div);
211 }
212 #endif
213 
214 static ulong zynq_clk_get_ddr3x_rate(struct zynq_clk_priv *priv)
215 {
216 	u32 clk_ctrl, div;
217 
218 	clk_ctrl = readl(&slcr_base->ddr_clk_ctrl);
219 
220 	div = (clk_ctrl & CLK_CTRL_DIV3X_MASK) >> CLK_CTRL_DIV3X_SHIFT;
221 
222 	return DIV_ROUND_CLOSEST(zynq_clk_get_pll_rate(priv, ddrpll_clk), div);
223 }
224 
225 #ifndef CONFIG_SPL_BUILD
226 static ulong zynq_clk_get_dci_rate(struct zynq_clk_priv *priv)
227 {
228 	u32 clk_ctrl, div0, div1;
229 
230 	clk_ctrl = readl(&slcr_base->dci_clk_ctrl);
231 
232 	div0 = (clk_ctrl & CLK_CTRL_DIV0_MASK) >> CLK_CTRL_DIV0_SHIFT;
233 	div1 = (clk_ctrl & CLK_CTRL_DIV1_MASK) >> CLK_CTRL_DIV1_SHIFT;
234 
235 	return DIV_ROUND_CLOSEST(DIV_ROUND_CLOSEST(
236 		zynq_clk_get_pll_rate(priv, ddrpll_clk), div0), div1);
237 }
238 #endif
239 
240 static ulong zynq_clk_get_peripheral_rate(struct zynq_clk_priv *priv,
241 					  enum zynq_clk id, bool two_divs)
242 {
243 	enum zynq_clk pll;
244 	u32 clk_ctrl, div0;
245 	u32 div1 = 1;
246 
247 	clk_ctrl = readl(zynq_clk_get_register(id));
248 
249 	div0 = (clk_ctrl & CLK_CTRL_DIV0_MASK) >> CLK_CTRL_DIV0_SHIFT;
250 	if (!div0)
251 		div0 = 1;
252 
253 #ifndef CONFIG_SPL_BUILD
254 	if (two_divs) {
255 		div1 = (clk_ctrl & CLK_CTRL_DIV1_MASK) >> CLK_CTRL_DIV1_SHIFT;
256 		if (!div1)
257 			div1 = 1;
258 	}
259 #endif
260 
261 	pll = zynq_clk_get_peripheral_pll(clk_ctrl);
262 
263 	return
264 		DIV_ROUND_CLOSEST(
265 			DIV_ROUND_CLOSEST(
266 				zynq_clk_get_pll_rate(priv, pll), div0),
267 			div1);
268 }
269 
270 #ifndef CONFIG_SPL_BUILD
271 static ulong zynq_clk_get_gem_rate(struct zynq_clk_priv *priv, enum zynq_clk id)
272 {
273 	struct clk *parent;
274 
275 	if (zynq_clk_get_gem_rclk(id) == mio_clk)
276 		return zynq_clk_get_peripheral_rate(priv, id, true);
277 
278 	parent = &priv->gem_emio_clk[id - gem0_clk];
279 	if (parent->dev)
280 		return clk_get_rate(parent);
281 
282 	debug("%s: gem%d emio rx clock source unknown\n", __func__,
283 	      id - gem0_clk);
284 
285 	return -ENOSYS;
286 }
287 
288 static unsigned long zynq_clk_calc_peripheral_two_divs(ulong rate,
289 						       ulong pll_rate,
290 						       u32 *div0, u32 *div1)
291 {
292 	long new_err, best_err = (long)(~0UL >> 1);
293 	ulong new_rate, best_rate = 0;
294 	u32 d0, d1;
295 
296 	for (d0 = 1; d0 <= ZYNQ_CLK_MAXDIV; d0++) {
297 		for (d1 = 1; d1 <= ZYNQ_CLK_MAXDIV >> 1; d1++) {
298 			new_rate = DIV_ROUND_CLOSEST(
299 					DIV_ROUND_CLOSEST(pll_rate, d0), d1);
300 			new_err = abs(new_rate - rate);
301 
302 			if (new_err < best_err) {
303 				*div0 = d0;
304 				*div1 = d1;
305 				best_err = new_err;
306 				best_rate = new_rate;
307 			}
308 		}
309 	}
310 
311 	return best_rate;
312 }
313 
314 static ulong zynq_clk_set_peripheral_rate(struct zynq_clk_priv *priv,
315 					  enum zynq_clk id, ulong rate,
316 					  bool two_divs)
317 {
318 	enum zynq_clk pll;
319 	u32 clk_ctrl, div0 = 0, div1 = 0;
320 	ulong pll_rate, new_rate;
321 	u32 *reg;
322 
323 	reg = zynq_clk_get_register(id);
324 	clk_ctrl = readl(reg);
325 
326 	pll = zynq_clk_get_peripheral_pll(clk_ctrl);
327 	pll_rate = zynq_clk_get_pll_rate(priv, pll);
328 	clk_ctrl &= ~CLK_CTRL_DIV0_MASK;
329 	if (two_divs) {
330 		clk_ctrl &= ~CLK_CTRL_DIV1_MASK;
331 		new_rate = zynq_clk_calc_peripheral_two_divs(rate, pll_rate,
332 				&div0, &div1);
333 		clk_ctrl |= div1 << CLK_CTRL_DIV1_SHIFT;
334 	} else {
335 		div0 = DIV_ROUND_CLOSEST(pll_rate, rate);
336 		if (div0 > ZYNQ_CLK_MAXDIV)
337 			div0 = ZYNQ_CLK_MAXDIV;
338 		new_rate = DIV_ROUND_CLOSEST(rate, div0);
339 	}
340 	clk_ctrl |= div0 << CLK_CTRL_DIV0_SHIFT;
341 
342 	zynq_slcr_unlock();
343 	writel(clk_ctrl, reg);
344 	zynq_slcr_lock();
345 
346 	return new_rate;
347 }
348 
349 static ulong zynq_clk_set_gem_rate(struct zynq_clk_priv *priv, enum zynq_clk id,
350 				   ulong rate)
351 {
352 	struct clk *parent;
353 
354 	if (zynq_clk_get_gem_rclk(id) == mio_clk)
355 		return zynq_clk_set_peripheral_rate(priv, id, rate, true);
356 
357 	parent = &priv->gem_emio_clk[id - gem0_clk];
358 	if (parent->dev)
359 		return clk_set_rate(parent, rate);
360 
361 	debug("%s: gem%d emio rx clock source unknown\n", __func__,
362 	      id - gem0_clk);
363 
364 	return -ENOSYS;
365 }
366 #endif
367 
368 #ifndef CONFIG_SPL_BUILD
369 static ulong zynq_clk_get_rate(struct clk *clk)
370 {
371 	struct zynq_clk_priv *priv = dev_get_priv(clk->dev);
372 	enum zynq_clk id = clk->id;
373 	bool two_divs = false;
374 
375 	switch (id) {
376 	case armpll_clk ... iopll_clk:
377 		return zynq_clk_get_pll_rate(priv, id);
378 	case cpu_6or4x_clk ... cpu_1x_clk:
379 		return zynq_clk_get_cpu_rate(priv, id);
380 	case ddr2x_clk:
381 		return zynq_clk_get_ddr2x_rate(priv);
382 	case ddr3x_clk:
383 		return zynq_clk_get_ddr3x_rate(priv);
384 	case dci_clk:
385 		return zynq_clk_get_dci_rate(priv);
386 	case gem0_clk ... gem1_clk:
387 		return zynq_clk_get_gem_rate(priv, id);
388 	case fclk0_clk ... can1_clk:
389 		two_divs = true;
390 		/* fall through */
391 	case dbg_trc_clk ... dbg_apb_clk:
392 	case lqspi_clk ... pcap_clk:
393 	case sdio0_clk ... spi1_clk:
394 		return zynq_clk_get_peripheral_rate(priv, id, two_divs);
395 	case dma_clk:
396 		return zynq_clk_get_cpu_rate(priv, cpu_2x_clk);
397 	case usb0_aper_clk ... smc_aper_clk:
398 		return zynq_clk_get_cpu_rate(priv, cpu_1x_clk);
399 	default:
400 		return -ENXIO;
401 	}
402 }
403 
404 static ulong zynq_clk_set_rate(struct clk *clk, ulong rate)
405 {
406 	struct zynq_clk_priv *priv = dev_get_priv(clk->dev);
407 	enum zynq_clk id = clk->id;
408 	bool two_divs = false;
409 
410 	switch (id) {
411 	case gem0_clk ... gem1_clk:
412 		return zynq_clk_set_gem_rate(priv, id, rate);
413 	case fclk0_clk ... can1_clk:
414 		two_divs = true;
415 		/* fall through */
416 	case lqspi_clk ... pcap_clk:
417 	case sdio0_clk ... spi1_clk:
418 	case dbg_trc_clk ... dbg_apb_clk:
419 		return zynq_clk_set_peripheral_rate(priv, id, rate, two_divs);
420 	default:
421 		return -ENXIO;
422 	}
423 }
424 #else
425 static ulong zynq_clk_get_rate(struct clk *clk)
426 {
427 	struct zynq_clk_priv *priv = dev_get_priv(clk->dev);
428 	enum zynq_clk id = clk->id;
429 
430 	switch (id) {
431 	case cpu_6or4x_clk ... cpu_1x_clk:
432 		return zynq_clk_get_cpu_rate(priv, id);
433 	case ddr3x_clk:
434 		return zynq_clk_get_ddr3x_rate(priv);
435 	case lqspi_clk ... pcap_clk:
436 	case sdio0_clk ... spi1_clk:
437 		return zynq_clk_get_peripheral_rate(priv, id, 0);
438 	default:
439 		return -ENXIO;
440 	}
441 }
442 #endif
443 
444 static struct clk_ops zynq_clk_ops = {
445 	.get_rate = zynq_clk_get_rate,
446 #ifndef CONFIG_SPL_BUILD
447 	.set_rate = zynq_clk_set_rate,
448 #endif
449 };
450 
451 static int zynq_clk_probe(struct udevice *dev)
452 {
453 	struct zynq_clk_priv *priv = dev_get_priv(dev);
454 #ifndef CONFIG_SPL_BUILD
455 	unsigned int i;
456 	char name[16];
457 	int ret;
458 
459 	for (i = 0; i < 2; i++) {
460 		sprintf(name, "gem%d_emio_clk", i);
461 		ret = clk_get_by_name(dev, name, &priv->gem_emio_clk[i]);
462 		if (ret < 0 && ret != -FDT_ERR_NOTFOUND) {
463 			dev_err(dev, "failed to get %s clock\n", name);
464 			return ret;
465 		}
466 	}
467 #endif
468 
469 	priv->ps_clk_freq = fdtdec_get_uint(gd->fdt_blob, dev->of_offset,
470 					    "ps-clk-frequency", 33333333UL);
471 
472 	return 0;
473 }
474 
475 static const struct udevice_id zynq_clk_ids[] = {
476 	{ .compatible = "xlnx,ps7-clkc"},
477 	{}
478 };
479 
480 U_BOOT_DRIVER(zynq_clk) = {
481 	.name		= "zynq_clk",
482 	.id		= UCLASS_CLK,
483 	.of_match	= zynq_clk_ids,
484 	.flags		= DM_FLAG_PRE_RELOC,
485 	.ops		= &zynq_clk_ops,
486 	.priv_auto_alloc_size = sizeof(struct zynq_clk_priv),
487 	.probe		= zynq_clk_probe,
488 };
489