xref: /freebsd/sys/arm/xilinx/zy7_slcr.c (revision 6b129086dcee14496517fae085b448e3edc69bc7)
1 /*-
2  * Copyright (c) 2013 Thomas Skibo
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  * $FreeBSD$
27  */
28 
29 /*
30  * Zynq-700 SLCR driver.  Provides hooks for cpu_reset and PL control stuff.
31  * In the future, maybe MIO control, clock control, etc. could go here.
32  *
33  * Reference: Zynq-7000 All Programmable SoC Technical Reference Manual.
34  * (v1.4) November 16, 2012.  Xilinx doc UG585.
35  */
36 
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/conf.h>
43 #include <sys/kernel.h>
44 #include <sys/module.h>
45 #include <sys/lock.h>
46 #include <sys/mutex.h>
47 #include <sys/resource.h>
48 #include <sys/sysctl.h>
49 #include <sys/rman.h>
50 
51 #include <machine/bus.h>
52 #include <machine/resource.h>
53 #include <machine/stdarg.h>
54 
55 #include <dev/fdt/fdt_common.h>
56 #include <dev/ofw/ofw_bus.h>
57 #include <dev/ofw/ofw_bus_subr.h>
58 
59 #include <arm/xilinx/zy7_slcr.h>
60 
61 struct zy7_slcr_softc {
62 	device_t	dev;
63 	struct mtx	sc_mtx;
64 	struct resource	*mem_res;
65 };
66 
67 static struct zy7_slcr_softc *zy7_slcr_softc_p;
68 extern void (*zynq7_cpu_reset);
69 
70 #define ZSLCR_LOCK(sc)		mtx_lock(&(sc)->sc_mtx)
71 #define	ZSLCR_UNLOCK(sc)		mtx_unlock(&(sc)->sc_mtx)
72 #define ZSLCR_LOCK_INIT(sc) \
73 	mtx_init(&(sc)->sc_mtx, device_get_nameunit((sc)->dev),	\
74 	    "zy7_slcr", MTX_DEF)
75 #define ZSLCR_LOCK_DESTROY(_sc)	mtx_destroy(&_sc->sc_mtx);
76 
77 #define RD4(sc, off) 		(bus_read_4((sc)->mem_res, (off)))
78 #define WR4(sc, off, val) 	(bus_write_4((sc)->mem_res, (off), (val)))
79 
80 #define ZYNQ_DEFAULT_PS_CLK_FREQUENCY	33333333	/* 33.3 Mhz */
81 
82 
83 SYSCTL_NODE(_hw, OID_AUTO, zynq, CTLFLAG_RD, 0, "Xilinx Zynq-7000");
84 
85 static char zynq_bootmode[64];
86 SYSCTL_STRING(_hw_zynq, OID_AUTO, bootmode, CTLFLAG_RD, zynq_bootmode, 0,
87 	      "Zynq boot mode");
88 
89 static char zynq_pssid[100];
90 SYSCTL_STRING(_hw_zynq, OID_AUTO, pssid, CTLFLAG_RD, zynq_pssid, 0,
91 	   "Zynq PSS IDCODE");
92 
93 static uint32_t zynq_reboot_status;
94 SYSCTL_INT(_hw_zynq, OID_AUTO, reboot_status, CTLFLAG_RD, &zynq_reboot_status,
95 	   0, "Zynq REBOOT_STATUS register");
96 
97 static int ps_clk_frequency;
98 SYSCTL_INT(_hw_zynq, OID_AUTO, ps_clk_frequency, CTLFLAG_RD, &ps_clk_frequency,
99 	   0, "Zynq PS_CLK Frequency");
100 
101 static int io_pll_frequency;
102 SYSCTL_INT(_hw_zynq, OID_AUTO, io_pll_frequency, CTLFLAG_RD, &io_pll_frequency,
103 	   0, "Zynq IO PLL Frequency");
104 
105 static int arm_pll_frequency;
106 SYSCTL_INT(_hw_zynq, OID_AUTO, arm_pll_frequency, CTLFLAG_RD,
107 	   &arm_pll_frequency, 0, "Zynq ARM PLL Frequency");
108 
109 static int ddr_pll_frequency;
110 SYSCTL_INT(_hw_zynq, OID_AUTO, ddr_pll_frequency, CTLFLAG_RD,
111 	   &ddr_pll_frequency, 0, "Zynq DDR PLL Frequency");
112 
113 static void
114 zy7_slcr_unlock(struct zy7_slcr_softc *sc)
115 {
116 
117 	/* Unlock SLCR with magic number. */
118 	WR4(sc, ZY7_SLCR_UNLOCK, ZY7_SLCR_UNLOCK_MAGIC);
119 }
120 
121 static void
122 zy7_slcr_lock(struct zy7_slcr_softc *sc)
123 {
124 
125 	/* Lock SLCR with magic number. */
126 	WR4(sc, ZY7_SLCR_LOCK, ZY7_SLCR_LOCK_MAGIC);
127 }
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 controled 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 static int
259 zy7_slcr_probe(device_t dev)
260 {
261 
262 	if (!ofw_bus_status_okay(dev))
263 		return (ENXIO);
264 
265 	if (!ofw_bus_is_compatible(dev, "xlnx,zy7_slcr"))
266 		return (ENXIO);
267 
268 	device_set_desc(dev, "Zynq-7000 slcr block");
269 	return (0);
270 }
271 
272 static int
273 zy7_slcr_attach(device_t dev)
274 {
275 	struct zy7_slcr_softc *sc = device_get_softc(dev);
276 	int rid;
277 	phandle_t node;
278 	pcell_t cell;
279 	uint32_t bootmode;
280 	uint32_t pss_idcode;
281 	uint32_t arm_pll_ctrl;
282 	uint32_t ddr_pll_ctrl;
283 	uint32_t io_pll_ctrl;
284 	static char *bootdev_names[] = {
285 		"JTAG", "Quad-SPI", "NOR", "(3?)",
286 		"NAND", "SD Card", "(6?)", "(7?)"
287 	};
288 
289 	/* Allow only one attach. */
290 	if (zy7_slcr_softc_p != NULL)
291 		return (ENXIO);
292 
293 	sc->dev = dev;
294 
295 	ZSLCR_LOCK_INIT(sc);
296 
297 	/* Get memory resource. */
298 	rid = 0;
299 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
300 					     RF_ACTIVE);
301 	if (sc->mem_res == NULL) {
302 		device_printf(dev, "could not allocate memory resources.\n");
303 		return (ENOMEM);
304 	}
305 
306 	/* Hook up cpu_reset. */
307 	zy7_slcr_softc_p = sc;
308 	zynq7_cpu_reset = zy7_slcr_cpu_reset;
309 
310 	/* Read info and set sysctls. */
311 	bootmode = RD4(sc, ZY7_SLCR_BOOT_MODE);
312 	snprintf(zynq_bootmode, sizeof(zynq_bootmode),
313 		 "0x%x: boot device: %s", bootmode,
314 		 bootdev_names[bootmode & ZY7_SLCR_BOOT_MODE_BOOTDEV_MASK]);
315 
316 	pss_idcode = RD4(sc, ZY7_SLCR_PSS_IDCODE);
317 	snprintf(zynq_pssid, sizeof(zynq_pssid),
318 		 "0x%x: manufacturer: 0x%x device: 0x%x "
319 		 "family: 0x%x sub-family: 0x%x rev: 0x%x",
320 		 pss_idcode,
321 		 (pss_idcode & ZY7_SLCR_PSS_IDCODE_MNFR_ID_MASK) >>
322 		 ZY7_SLCR_PSS_IDCODE_MNFR_ID_SHIFT,
323 		 (pss_idcode & ZY7_SLCR_PSS_IDCODE_DEVICE_MASK) >>
324 		 ZY7_SLCR_PSS_IDCODE_DEVICE_SHIFT,
325 		 (pss_idcode & ZY7_SLCR_PSS_IDCODE_FAMILY_MASK) >>
326 		 ZY7_SLCR_PSS_IDCODE_FAMILY_SHIFT,
327 		 (pss_idcode & ZY7_SLCR_PSS_IDCODE_SUB_FAMILY_MASK) >>
328 		 ZY7_SLCR_PSS_IDCODE_SUB_FAMILY_SHIFT,
329 		 (pss_idcode & ZY7_SLCR_PSS_IDCODE_REVISION_MASK) >>
330 		 ZY7_SLCR_PSS_IDCODE_REVISION_SHIFT);
331 
332 	zynq_reboot_status = RD4(sc, ZY7_SLCR_REBOOT_STAT);
333 
334 	/* Derive PLL frequencies from PS_CLK. */
335 	node = ofw_bus_get_node(dev);
336 	if (OF_getprop(node, "clock-frequency", &cell, sizeof(cell)) > 0)
337 		ps_clk_frequency = fdt32_to_cpu(cell);
338 	else
339 		ps_clk_frequency = ZYNQ_DEFAULT_PS_CLK_FREQUENCY;
340 
341 	arm_pll_ctrl = RD4(sc, ZY7_SLCR_ARM_PLL_CTRL);
342 	ddr_pll_ctrl = RD4(sc, ZY7_SLCR_DDR_PLL_CTRL);
343 	io_pll_ctrl = RD4(sc, ZY7_SLCR_IO_PLL_CTRL);
344 
345 	/* Determine ARM PLL frequency. */
346 	if (((arm_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_QUAL) == 0 &&
347 	     (arm_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_FORCE) != 0) ||
348 	    ((arm_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_QUAL) != 0 &&
349 	     (bootmode & ZY7_SLCR_BOOT_MODE_PLL_BYPASS) != 0))
350 		/* PLL is bypassed. */
351 		arm_pll_frequency = ps_clk_frequency;
352 	else
353 		arm_pll_frequency = ps_clk_frequency *
354 			((arm_pll_ctrl & ZY7_SLCR_PLL_CTRL_FDIV_MASK) >>
355 			 ZY7_SLCR_PLL_CTRL_FDIV_SHIFT);
356 
357 	/* Determine DDR PLL frequency. */
358 	if (((ddr_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_QUAL) == 0 &&
359 	     (ddr_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_FORCE) != 0) ||
360 	    ((ddr_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_QUAL) != 0 &&
361 	     (bootmode & ZY7_SLCR_BOOT_MODE_PLL_BYPASS) != 0))
362 		/* PLL is bypassed. */
363 		ddr_pll_frequency = ps_clk_frequency;
364 	else
365 		ddr_pll_frequency = ps_clk_frequency *
366 			((ddr_pll_ctrl & ZY7_SLCR_PLL_CTRL_FDIV_MASK) >>
367 			 ZY7_SLCR_PLL_CTRL_FDIV_SHIFT);
368 
369 	/* Determine IO PLL frequency. */
370 	if (((io_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_QUAL) == 0 &&
371 	     (io_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_FORCE) != 0) ||
372 	    ((io_pll_ctrl & ZY7_SLCR_PLL_CTRL_BYPASS_QUAL) != 0 &&
373 	     (bootmode & ZY7_SLCR_BOOT_MODE_PLL_BYPASS) != 0))
374 		/* PLL is bypassed. */
375 		io_pll_frequency = ps_clk_frequency;
376 	else
377 		io_pll_frequency = ps_clk_frequency *
378 			((io_pll_ctrl & ZY7_SLCR_PLL_CTRL_FDIV_MASK) >>
379 			 ZY7_SLCR_PLL_CTRL_FDIV_SHIFT);
380 
381 	/* Lock SLCR registers. */
382 	zy7_slcr_lock(sc);
383 
384 	return (0);
385 }
386 
387 static int
388 zy7_slcr_detach(device_t dev)
389 {
390 	struct zy7_slcr_softc *sc = device_get_softc(dev);
391 
392 	bus_generic_detach(dev);
393 
394 	/* Release memory resource. */
395 	if (sc->mem_res != NULL)
396 		bus_release_resource(dev, SYS_RES_MEMORY,
397 			     rman_get_rid(sc->mem_res), sc->mem_res);
398 
399 	zy7_slcr_softc_p = NULL;
400 	zynq7_cpu_reset = NULL;
401 
402 	ZSLCR_LOCK_DESTROY(sc);
403 
404 	return (0);
405 }
406 
407 static device_method_t zy7_slcr_methods[] = {
408 	/* device_if */
409 	DEVMETHOD(device_probe, 	zy7_slcr_probe),
410 	DEVMETHOD(device_attach, 	zy7_slcr_attach),
411 	DEVMETHOD(device_detach, 	zy7_slcr_detach),
412 
413 	DEVMETHOD_END
414 };
415 
416 static driver_t zy7_slcr_driver = {
417 	"zy7_slcr",
418 	zy7_slcr_methods,
419 	sizeof(struct zy7_slcr_softc),
420 };
421 static devclass_t zy7_slcr_devclass;
422 
423 DRIVER_MODULE(zy7_slcr, simplebus, zy7_slcr_driver, zy7_slcr_devclass, 0, 0);
424 MODULE_VERSION(zy7_slcr, 1);
425