xref: /freebsd/sys/arm/xilinx/zy7_slcr.c (revision ce6a89e27cd190313be39bb479880aeda4778436)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2013 Thomas Skibo
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 /*
32  * Zynq-700 SLCR driver.  Provides hooks for cpu_reset and PL control stuff.
33  * In the future, maybe MIO control, clock control, etc. could go here.
34  *
35  * Reference: Zynq-7000 All Programmable SoC Technical Reference Manual.
36  * (v1.4) November 16, 2012.  Xilinx doc UG585.
37  */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/conf.h>
45 #include <sys/kernel.h>
46 #include <sys/module.h>
47 #include <sys/lock.h>
48 #include <sys/mutex.h>
49 #include <sys/resource.h>
50 #include <sys/sysctl.h>
51 #include <sys/rman.h>
52 
53 #include <machine/bus.h>
54 #include <machine/resource.h>
55 #include <machine/stdarg.h>
56 
57 #include <dev/ofw/ofw_bus.h>
58 #include <dev/ofw/ofw_bus_subr.h>
59 
60 #include <arm/xilinx/zy7_slcr.h>
61 
62 struct zy7_slcr_softc {
63 	device_t	dev;
64 	struct mtx	sc_mtx;
65 	struct resource	*mem_res;
66 };
67 
68 static struct zy7_slcr_softc *zy7_slcr_softc_p;
69 extern void (*zynq7_cpu_reset);
70 
71 #define ZSLCR_LOCK(sc)		mtx_lock(&(sc)->sc_mtx)
72 #define	ZSLCR_UNLOCK(sc)		mtx_unlock(&(sc)->sc_mtx)
73 #define ZSLCR_LOCK_INIT(sc) \
74 	mtx_init(&(sc)->sc_mtx, device_get_nameunit((sc)->dev),	\
75 	    "zy7_slcr", MTX_DEF)
76 #define ZSLCR_LOCK_DESTROY(_sc)	mtx_destroy(&_sc->sc_mtx);
77 
78 #define RD4(sc, off) 		(bus_read_4((sc)->mem_res, (off)))
79 #define WR4(sc, off, val) 	(bus_write_4((sc)->mem_res, (off), (val)))
80 
81 #define ZYNQ_DEFAULT_PS_CLK_FREQUENCY	33333333	/* 33.3 Mhz */
82 
83 SYSCTL_NODE(_hw, OID_AUTO, zynq, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
84     "Xilinx Zynq-7000");
85 
86 static char zynq_bootmode[64];
87 SYSCTL_STRING(_hw_zynq, OID_AUTO, bootmode, CTLFLAG_RD, zynq_bootmode, 0,
88 	      "Zynq boot mode");
89 
90 static char zynq_pssid[100];
91 SYSCTL_STRING(_hw_zynq, OID_AUTO, pssid, CTLFLAG_RD, zynq_pssid, 0,
92 	   "Zynq PSS IDCODE");
93 
94 static uint32_t zynq_reboot_status;
95 SYSCTL_INT(_hw_zynq, OID_AUTO, reboot_status, CTLFLAG_RD, &zynq_reboot_status,
96 	   0, "Zynq REBOOT_STATUS register");
97 
98 static int ps_clk_frequency;
99 SYSCTL_INT(_hw_zynq, OID_AUTO, ps_clk_frequency, CTLFLAG_RD, &ps_clk_frequency,
100 	   0, "Zynq PS_CLK Frequency");
101 
102 static int io_pll_frequency;
103 SYSCTL_INT(_hw_zynq, OID_AUTO, io_pll_frequency, CTLFLAG_RD, &io_pll_frequency,
104 	   0, "Zynq IO PLL Frequency");
105 
106 static int arm_pll_frequency;
107 SYSCTL_INT(_hw_zynq, OID_AUTO, arm_pll_frequency, CTLFLAG_RD,
108 	   &arm_pll_frequency, 0, "Zynq ARM PLL Frequency");
109 
110 static int ddr_pll_frequency;
111 SYSCTL_INT(_hw_zynq, OID_AUTO, ddr_pll_frequency, CTLFLAG_RD,
112 	   &ddr_pll_frequency, 0, "Zynq DDR PLL Frequency");
113 
114 static void
115 zy7_slcr_unlock(struct zy7_slcr_softc *sc)
116 {
117 
118 	/* Unlock SLCR with magic number. */
119 	WR4(sc, ZY7_SLCR_UNLOCK, ZY7_SLCR_UNLOCK_MAGIC);
120 }
121 
122 static void
123 zy7_slcr_lock(struct zy7_slcr_softc *sc)
124 {
125 
126 	/* Lock SLCR with magic number. */
127 	WR4(sc, ZY7_SLCR_LOCK, ZY7_SLCR_LOCK_MAGIC);
128 }
129 
130 static void
131 zy7_slcr_cpu_reset(void)
132 {
133 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
134 
135 	/* Unlock SLCR registers. */
136 	zy7_slcr_unlock(sc);
137 
138 	/* This has something to do with a work-around so the fsbl will load
139 	 * the bitstream after soft-reboot.  It's very important.
140 	 */
141 	WR4(sc, ZY7_SLCR_REBOOT_STAT,
142 	    RD4(sc, ZY7_SLCR_REBOOT_STAT) & 0xf0ffffff);
143 
144 	/* Soft reset */
145 	WR4(sc, ZY7_SLCR_PSS_RST_CTRL, ZY7_SLCR_PSS_RST_CTRL_SOFT_RESET);
146 
147 	for (;;)
148 		;
149 }
150 
151 /* Assert PL resets and disable level shifters in preparation of programming
152  * the PL (FPGA) section.  Called from zy7_devcfg.c.
153  */
154 void
155 zy7_slcr_preload_pl(void)
156 {
157 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
158 
159 	if (!sc)
160 		return;
161 
162 	ZSLCR_LOCK(sc);
163 
164 	/* Unlock SLCR registers. */
165 	zy7_slcr_unlock(sc);
166 
167 	/* Assert top level output resets. */
168 	WR4(sc, ZY7_SLCR_FPGA_RST_CTRL, ZY7_SLCR_FPGA_RST_CTRL_RST_ALL);
169 
170 	/* Disable all level shifters. */
171 	WR4(sc, ZY7_SLCR_LVL_SHFTR_EN, 0);
172 
173 	/* Lock SLCR registers. */
174 	zy7_slcr_lock(sc);
175 
176 	ZSLCR_UNLOCK(sc);
177 }
178 
179 /* After PL configuration, enable level shifters and deassert top-level
180  * PL resets.  Called from zy7_devcfg.c.  Optionally, the level shifters
181  * can be left disabled but that's rare of an FPGA application. That option
182  * is controlled by a sysctl in the devcfg driver.
183  */
184 void
185 zy7_slcr_postload_pl(int en_level_shifters)
186 {
187 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
188 
189 	if (!sc)
190 		return;
191 
192 	ZSLCR_LOCK(sc);
193 
194 	/* Unlock SLCR registers. */
195 	zy7_slcr_unlock(sc);
196 
197 	if (en_level_shifters)
198 		/* Enable level shifters. */
199 		WR4(sc, ZY7_SLCR_LVL_SHFTR_EN, ZY7_SLCR_LVL_SHFTR_EN_ALL);
200 
201 	/* Deassert top level output resets. */
202 	WR4(sc, ZY7_SLCR_FPGA_RST_CTRL, 0);
203 
204 	/* Lock SLCR registers. */
205 	zy7_slcr_lock(sc);
206 
207 	ZSLCR_UNLOCK(sc);
208 }
209 
210 /* Override cgem_set_refclk() in gigabit ethernet driver
211  * (sys/dev/cadence/if_cgem.c).  This function is called to
212  * request a change in the gem's reference clock speed.
213  */
214 int
215 cgem_set_ref_clk(int unit, int frequency)
216 {
217 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
218 	int div0, div1;
219 
220 	if (!sc)
221 		return (-1);
222 
223 	/* Find suitable divisor pairs.  Round result to nearest khz
224 	 * to test for match.
225 	 */
226 	for (div1 = 1; div1 <= ZY7_SLCR_GEM_CLK_CTRL_DIVISOR1_MAX; div1++) {
227 		div0 = (io_pll_frequency + div1 * frequency / 2) /
228 			div1 / frequency;
229 		if (div0 > 0 && div0 <= ZY7_SLCR_GEM_CLK_CTRL_DIVISOR_MAX &&
230 		    ((io_pll_frequency / div0 / div1) + 500) / 1000 ==
231 		    (frequency + 500) / 1000)
232 			break;
233 	}
234 
235 	if (div1 > ZY7_SLCR_GEM_CLK_CTRL_DIVISOR1_MAX)
236 		return (-1);
237 
238 	ZSLCR_LOCK(sc);
239 
240 	/* Unlock SLCR registers. */
241 	zy7_slcr_unlock(sc);
242 
243 	/* Modify GEM reference clock. */
244 	WR4(sc, unit ? ZY7_SLCR_GEM1_CLK_CTRL : ZY7_SLCR_GEM0_CLK_CTRL,
245 	    (div1 << ZY7_SLCR_GEM_CLK_CTRL_DIVISOR1_SHIFT) |
246 	    (div0 << ZY7_SLCR_GEM_CLK_CTRL_DIVISOR_SHIFT) |
247 	    ZY7_SLCR_GEM_CLK_CTRL_SRCSEL_IO_PLL |
248 	    ZY7_SLCR_GEM_CLK_CTRL_CLKACT);
249 
250 	/* Lock SLCR registers. */
251 	zy7_slcr_lock(sc);
252 
253 	ZSLCR_UNLOCK(sc);
254 
255 	return (0);
256 }
257 
258 /*
259  * PL clocks management function
260  */
261 int
262 zy7_pl_fclk_set_source(int unit, int source)
263 {
264 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
265 	uint32_t reg;
266 
267 	if (!sc)
268 		return (-1);
269 
270 	ZSLCR_LOCK(sc);
271 
272 	/* Unlock SLCR registers. */
273 	zy7_slcr_unlock(sc);
274 
275 	/* Modify FPGAx source. */
276 	reg = RD4(sc, ZY7_SLCR_FPGA_CLK_CTRL(unit));
277 	reg &= ~(ZY7_SLCR_FPGA_CLK_CTRL_SRCSEL_MASK);
278 	reg |= (source << ZY7_SLCR_FPGA_CLK_CTRL_SRCSEL_SHIFT);
279 	WR4(sc, ZY7_SLCR_FPGA_CLK_CTRL(unit), reg);
280 
281 	/* Lock SLCR registers. */
282 	zy7_slcr_lock(sc);
283 
284 	ZSLCR_UNLOCK(sc);
285 
286 	return (0);
287 }
288 
289 int
290 zy7_pl_fclk_get_source(int unit)
291 {
292 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
293 	uint32_t reg;
294 	int source;
295 
296 	if (!sc)
297 		return (-1);
298 
299 	ZSLCR_LOCK(sc);
300 
301 	/* Modify GEM reference clock. */
302 	reg = RD4(sc, ZY7_SLCR_FPGA_CLK_CTRL(unit));
303 	source = (reg & ZY7_SLCR_FPGA_CLK_CTRL_SRCSEL_MASK) >>
304 	    ZY7_SLCR_FPGA_CLK_CTRL_SRCSEL_SHIFT;
305 
306 	/* ZY7_PL_FCLK_SRC_IO is actually b0x */
307 	if ((source & 2) == 0)
308 		source = ZY7_PL_FCLK_SRC_IO;
309 
310 	ZSLCR_UNLOCK(sc);
311 
312 	return (source);
313 }
314 
315 int
316 zy7_pl_fclk_set_freq(int unit, int frequency)
317 {
318 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
319 	int div0, div1;
320 	int base_frequency;
321 	uint32_t reg;
322 	int source;
323 
324 	if (!sc)
325 		return (-1);
326 
327 	source = zy7_pl_fclk_get_source(unit);
328 	switch (source) {
329 		case ZY7_PL_FCLK_SRC_IO:
330 			base_frequency = io_pll_frequency;
331 			break;
332 
333 		case ZY7_PL_FCLK_SRC_ARM:
334 			base_frequency = arm_pll_frequency;
335 			break;
336 
337 		case ZY7_PL_FCLK_SRC_DDR:
338 			base_frequency = ddr_pll_frequency;
339 			break;
340 
341 		default:
342 			return (-1);
343 	}
344 
345 	/* Find suitable divisor pairs.  Round result to nearest khz
346 	 * to test for match.
347 	 */
348 	for (div1 = 1; div1 <= ZY7_SLCR_FPGA_CLK_CTRL_DIVISOR_MAX; div1++) {
349 		div0 = (base_frequency + div1 * frequency / 2) /
350 			div1 / frequency;
351 		if (div0 > 0 && div0 <= ZY7_SLCR_FPGA_CLK_CTRL_DIVISOR_MAX &&
352 		    ((base_frequency / div0 / div1) + 500) / 1000 ==
353 		    (frequency + 500) / 1000)
354 			break;
355 	}
356 
357 	if (div1 > ZY7_SLCR_FPGA_CLK_CTRL_DIVISOR_MAX)
358 		return (-1);
359 
360 	ZSLCR_LOCK(sc);
361 
362 	/* Unlock SLCR registers. */
363 	zy7_slcr_unlock(sc);
364 
365 	/* Modify FPGAx reference clock. */
366 	reg = RD4(sc, ZY7_SLCR_FPGA_CLK_CTRL(unit));
367 	reg &= ~(ZY7_SLCR_FPGA_CLK_CTRL_DIVISOR1_MASK |
368 	    ZY7_SLCR_FPGA_CLK_CTRL_DIVISOR0_MASK);
369 	reg |= (div1 << ZY7_SLCR_FPGA_CLK_CTRL_DIVISOR1_SHIFT) |
370 	    (div0 << ZY7_SLCR_FPGA_CLK_CTRL_DIVISOR0_SHIFT);
371 	WR4(sc, ZY7_SLCR_FPGA_CLK_CTRL(unit), reg);
372 
373 	/* Lock SLCR registers. */
374 	zy7_slcr_lock(sc);
375 
376 	ZSLCR_UNLOCK(sc);
377 
378 	return (base_frequency / div0 / div1);
379 }
380 
381 int
382 zy7_pl_fclk_get_freq(int unit)
383 {
384 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
385 	int div0, div1;
386 	int base_frequency;
387 	int frequency;
388 	uint32_t reg;
389 	int source;
390 
391 	if (!sc)
392 		return (-1);
393 
394 	source = zy7_pl_fclk_get_source(unit);
395 	switch (source) {
396 		case ZY7_PL_FCLK_SRC_IO:
397 			base_frequency = io_pll_frequency;
398 			break;
399 
400 		case ZY7_PL_FCLK_SRC_ARM:
401 			base_frequency = arm_pll_frequency;
402 			break;
403 
404 		case ZY7_PL_FCLK_SRC_DDR:
405 			base_frequency = ddr_pll_frequency;
406 			break;
407 
408 		default:
409 			return (-1);
410 	}
411 
412 	ZSLCR_LOCK(sc);
413 
414 	/* Modify FPGAx reference clock. */
415 	reg = RD4(sc, ZY7_SLCR_FPGA_CLK_CTRL(unit));
416 	div1 = (reg & ZY7_SLCR_FPGA_CLK_CTRL_DIVISOR1_MASK) >>
417 	    ZY7_SLCR_FPGA_CLK_CTRL_DIVISOR1_SHIFT;
418 	div0 = (reg & ZY7_SLCR_FPGA_CLK_CTRL_DIVISOR0_MASK) >>
419 	    ZY7_SLCR_FPGA_CLK_CTRL_DIVISOR0_SHIFT;
420 
421 	ZSLCR_UNLOCK(sc);
422 
423 	if (div0 == 0)
424 		div0 = 1;
425 
426 	if (div1 == 0)
427 		div1 = 1;
428 
429 	frequency = (base_frequency / div0 / div1);
430 	/* Round to KHz */
431 	frequency = (frequency + 500) / 1000;
432 	frequency = frequency * 1000;
433 
434 	return (frequency);
435 }
436 
437 int
438 zy7_pl_fclk_enable(int unit)
439 {
440 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
441 
442 	if (!sc)
443 		return (-1);
444 
445 	ZSLCR_LOCK(sc);
446 
447 	/* Unlock SLCR registers. */
448 	zy7_slcr_unlock(sc);
449 
450 	WR4(sc, ZY7_SLCR_FPGA_THR_CTRL(unit), 0);
451 	WR4(sc, ZY7_SLCR_FPGA_THR_CNT(unit), 0);
452 
453 	/* Lock SLCR registers. */
454 	zy7_slcr_lock(sc);
455 
456 	ZSLCR_UNLOCK(sc);
457 
458 	return (0);
459 }
460 
461 int
462 zy7_pl_fclk_disable(int unit)
463 {
464 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
465 
466 	if (!sc)
467 		return (-1);
468 
469 	ZSLCR_LOCK(sc);
470 
471 	/* Unlock SLCR registers. */
472 	zy7_slcr_unlock(sc);
473 
474 	WR4(sc, ZY7_SLCR_FPGA_THR_CTRL(unit), 0);
475 	WR4(sc, ZY7_SLCR_FPGA_THR_CNT(unit), 1);
476 
477 	/* Lock SLCR registers. */
478 	zy7_slcr_lock(sc);
479 
480 	ZSLCR_UNLOCK(sc);
481 
482 	return (0);
483 }
484 
485 int
486 zy7_pl_fclk_enabled(int unit)
487 {
488 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
489 	uint32_t reg;
490 
491 	if (!sc)
492 		return (-1);
493 
494 	ZSLCR_LOCK(sc);
495 	reg = RD4(sc, ZY7_SLCR_FPGA_THR_CNT(unit));
496 	ZSLCR_UNLOCK(sc);
497 
498 	return !(reg & 1);
499 }
500 
501 int
502 zy7_pl_level_shifters_enabled(void)
503 {
504 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
505 
506 	uint32_t reg;
507 
508 	if (!sc)
509 		return (-1);
510 
511 	ZSLCR_LOCK(sc);
512 	reg = RD4(sc, ZY7_SLCR_LVL_SHFTR_EN);
513 	ZSLCR_UNLOCK(sc);
514 
515 	return (reg == ZY7_SLCR_LVL_SHFTR_EN_ALL);
516 }
517 
518 void
519 zy7_pl_level_shifters_enable(void)
520 {
521 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
522 
523 	if (!sc)
524 		return;
525 
526 	ZSLCR_LOCK(sc);
527 	zy7_slcr_unlock(sc);
528 	WR4(sc, ZY7_SLCR_LVL_SHFTR_EN, ZY7_SLCR_LVL_SHFTR_EN_ALL);
529 	zy7_slcr_lock(sc);
530 	ZSLCR_UNLOCK(sc);
531 }
532 
533 void
534 zy7_pl_level_shifters_disable(void)
535 {
536 	struct zy7_slcr_softc *sc = zy7_slcr_softc_p;
537 
538 	if (!sc)
539 		return;
540 
541 	ZSLCR_LOCK(sc);
542 	zy7_slcr_unlock(sc);
543 	WR4(sc, ZY7_SLCR_LVL_SHFTR_EN, 0);
544 	zy7_slcr_lock(sc);
545 	ZSLCR_UNLOCK(sc);
546 }
547 
548 static int
549 zy7_slcr_probe(device_t dev)
550 {
551 
552 	if (!ofw_bus_status_okay(dev))
553 		return (ENXIO);
554 
555 	if (!ofw_bus_is_compatible(dev, "xlnx,zy7_slcr"))
556 		return (ENXIO);
557 
558 	device_set_desc(dev, "Zynq-7000 slcr block");
559 	return (0);
560 }
561 
562 static int
563 zy7_slcr_attach(device_t dev)
564 {
565 	struct zy7_slcr_softc *sc = device_get_softc(dev);
566 	int rid;
567 	phandle_t node;
568 	pcell_t cell;
569 	uint32_t bootmode;
570 	uint32_t pss_idcode;
571 	uint32_t arm_pll_ctrl;
572 	uint32_t ddr_pll_ctrl;
573 	uint32_t io_pll_ctrl;
574 	static char *bootdev_names[] = {
575 		"JTAG", "Quad-SPI", "NOR", "(3?)",
576 		"NAND", "SD Card", "(6?)", "(7?)"
577 	};
578 
579 	/* Allow only one attach. */
580 	if (zy7_slcr_softc_p != NULL)
581 		return (ENXIO);
582 
583 	sc->dev = dev;
584 
585 	ZSLCR_LOCK_INIT(sc);
586 
587 	/* Get memory resource. */
588 	rid = 0;
589 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
590 					     RF_ACTIVE);
591 	if (sc->mem_res == NULL) {
592 		device_printf(dev, "could not allocate memory resources.\n");
593 		return (ENOMEM);
594 	}
595 
596 	/* Hook up cpu_reset. */
597 	zy7_slcr_softc_p = sc;
598 	zynq7_cpu_reset = zy7_slcr_cpu_reset;
599 
600 	/* Read info and set sysctls. */
601 	bootmode = RD4(sc, ZY7_SLCR_BOOT_MODE);
602 	snprintf(zynq_bootmode, sizeof(zynq_bootmode),
603 		 "0x%x: boot device: %s", bootmode,
604 		 bootdev_names[bootmode & ZY7_SLCR_BOOT_MODE_BOOTDEV_MASK]);
605 
606 	pss_idcode = RD4(sc, ZY7_SLCR_PSS_IDCODE);
607 	snprintf(zynq_pssid, sizeof(zynq_pssid),
608 		 "0x%x: manufacturer: 0x%x device: 0x%x "
609 		 "family: 0x%x sub-family: 0x%x rev: 0x%x",
610 		 pss_idcode,
611 		 (pss_idcode & ZY7_SLCR_PSS_IDCODE_MNFR_ID_MASK) >>
612 		 ZY7_SLCR_PSS_IDCODE_MNFR_ID_SHIFT,
613 		 (pss_idcode & ZY7_SLCR_PSS_IDCODE_DEVICE_MASK) >>
614 		 ZY7_SLCR_PSS_IDCODE_DEVICE_SHIFT,
615 		 (pss_idcode & ZY7_SLCR_PSS_IDCODE_FAMILY_MASK) >>
616 		 ZY7_SLCR_PSS_IDCODE_FAMILY_SHIFT,
617 		 (pss_idcode & ZY7_SLCR_PSS_IDCODE_SUB_FAMILY_MASK) >>
618 		 ZY7_SLCR_PSS_IDCODE_SUB_FAMILY_SHIFT,
619 		 (pss_idcode & ZY7_SLCR_PSS_IDCODE_REVISION_MASK) >>
620 		 ZY7_SLCR_PSS_IDCODE_REVISION_SHIFT);
621 
622 	zynq_reboot_status = RD4(sc, ZY7_SLCR_REBOOT_STAT);
623 
624 	/* Derive PLL frequencies from PS_CLK. */
625 	node = ofw_bus_get_node(dev);
626 	if (OF_getencprop(node, "clock-frequency", &cell, sizeof(cell)) > 0)
627 		ps_clk_frequency = cell;
628 	else
629 		ps_clk_frequency = ZYNQ_DEFAULT_PS_CLK_FREQUENCY;
630 
631 	arm_pll_ctrl = RD4(sc, ZY7_SLCR_ARM_PLL_CTRL);
632 	ddr_pll_ctrl = RD4(sc, ZY7_SLCR_DDR_PLL_CTRL);
633 	io_pll_ctrl = RD4(sc, ZY7_SLCR_IO_PLL_CTRL);
634 
635 	/* Determine ARM PLL frequency. */
636 	if (((arm_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_QUAL) == 0 &&
637 	     (arm_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_FORCE) != 0) ||
638 	    ((arm_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_QUAL) != 0 &&
639 	     (bootmode & ZY7_SLCR_BOOT_MODE_PLL_BYPASS) != 0))
640 		/* PLL is bypassed. */
641 		arm_pll_frequency = ps_clk_frequency;
642 	else
643 		arm_pll_frequency = ps_clk_frequency *
644 			((arm_pll_ctrl & ZY7_SLCR_PLL_CTRL_FDIV_MASK) >>
645 			 ZY7_SLCR_PLL_CTRL_FDIV_SHIFT);
646 
647 	/* Determine DDR PLL frequency. */
648 	if (((ddr_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_QUAL) == 0 &&
649 	     (ddr_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_FORCE) != 0) ||
650 	    ((ddr_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_QUAL) != 0 &&
651 	     (bootmode & ZY7_SLCR_BOOT_MODE_PLL_BYPASS) != 0))
652 		/* PLL is bypassed. */
653 		ddr_pll_frequency = ps_clk_frequency;
654 	else
655 		ddr_pll_frequency = ps_clk_frequency *
656 			((ddr_pll_ctrl & ZY7_SLCR_PLL_CTRL_FDIV_MASK) >>
657 			 ZY7_SLCR_PLL_CTRL_FDIV_SHIFT);
658 
659 	/* Determine IO PLL frequency. */
660 	if (((io_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_QUAL) == 0 &&
661 	     (io_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_FORCE) != 0) ||
662 	    ((io_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_QUAL) != 0 &&
663 	     (bootmode & ZY7_SLCR_BOOT_MODE_PLL_BYPASS) != 0))
664 		/* PLL is bypassed. */
665 		io_pll_frequency = ps_clk_frequency;
666 	else
667 		io_pll_frequency = ps_clk_frequency *
668 			((io_pll_ctrl & ZY7_SLCR_PLL_CTRL_FDIV_MASK) >>
669 			 ZY7_SLCR_PLL_CTRL_FDIV_SHIFT);
670 
671 	/* Lock SLCR registers. */
672 	zy7_slcr_lock(sc);
673 
674 	return (0);
675 }
676 
677 static int
678 zy7_slcr_detach(device_t dev)
679 {
680 	struct zy7_slcr_softc *sc = device_get_softc(dev);
681 
682 	bus_generic_detach(dev);
683 
684 	/* Release memory resource. */
685 	if (sc->mem_res != NULL)
686 		bus_release_resource(dev, SYS_RES_MEMORY,
687 			     rman_get_rid(sc->mem_res), sc->mem_res);
688 
689 	zy7_slcr_softc_p = NULL;
690 	zynq7_cpu_reset = NULL;
691 
692 	ZSLCR_LOCK_DESTROY(sc);
693 
694 	return (0);
695 }
696 
697 static device_method_t zy7_slcr_methods[] = {
698 	/* device_if */
699 	DEVMETHOD(device_probe, 	zy7_slcr_probe),
700 	DEVMETHOD(device_attach, 	zy7_slcr_attach),
701 	DEVMETHOD(device_detach, 	zy7_slcr_detach),
702 
703 	DEVMETHOD_END
704 };
705 
706 static driver_t zy7_slcr_driver = {
707 	"zy7_slcr",
708 	zy7_slcr_methods,
709 	sizeof(struct zy7_slcr_softc),
710 };
711 static devclass_t zy7_slcr_devclass;
712 
713 DRIVER_MODULE(zy7_slcr, simplebus, zy7_slcr_driver, zy7_slcr_devclass, 0, 0);
714 MODULE_VERSION(zy7_slcr, 1);
715