xref: /openbmc/linux/drivers/usb/dwc2/core.c (revision 1c2dd16a)
1 /*
2  * core.c - DesignWare HS OTG Controller common routines
3  *
4  * Copyright (C) 2004-2013 Synopsys, Inc.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions, and the following disclaimer,
11  *    without modification.
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  * 3. The names of the above-listed copyright holders may not be used
16  *    to endorse or promote products derived from this software without
17  *    specific prior written permission.
18  *
19  * ALTERNATIVELY, this software may be distributed under the terms of the
20  * GNU General Public License ("GPL") as published by the Free Software
21  * Foundation; either version 2 of the License, or (at your option) any
22  * later version.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
25  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
26  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
27  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
28  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
29  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
30  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
31  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
32  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
33  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
34  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35  */
36 
37 /*
38  * The Core code provides basic services for accessing and managing the
39  * DWC_otg hardware. These services are used by both the Host Controller
40  * Driver and the Peripheral Controller Driver.
41  */
42 #include <linux/kernel.h>
43 #include <linux/module.h>
44 #include <linux/moduleparam.h>
45 #include <linux/spinlock.h>
46 #include <linux/interrupt.h>
47 #include <linux/dma-mapping.h>
48 #include <linux/delay.h>
49 #include <linux/io.h>
50 #include <linux/slab.h>
51 #include <linux/usb.h>
52 
53 #include <linux/usb/hcd.h>
54 #include <linux/usb/ch11.h>
55 
56 #include "core.h"
57 #include "hcd.h"
58 
59 /**
60  * dwc2_backup_global_registers() - Backup global controller registers.
61  * When suspending usb bus, registers needs to be backuped
62  * if controller power is disabled once suspended.
63  *
64  * @hsotg: Programming view of the DWC_otg controller
65  */
66 static int dwc2_backup_global_registers(struct dwc2_hsotg *hsotg)
67 {
68 	struct dwc2_gregs_backup *gr;
69 	int i;
70 
71 	/* Backup global regs */
72 	gr = &hsotg->gr_backup;
73 
74 	gr->gotgctl = dwc2_readl(hsotg->regs + GOTGCTL);
75 	gr->gintmsk = dwc2_readl(hsotg->regs + GINTMSK);
76 	gr->gahbcfg = dwc2_readl(hsotg->regs + GAHBCFG);
77 	gr->gusbcfg = dwc2_readl(hsotg->regs + GUSBCFG);
78 	gr->grxfsiz = dwc2_readl(hsotg->regs + GRXFSIZ);
79 	gr->gnptxfsiz = dwc2_readl(hsotg->regs + GNPTXFSIZ);
80 	gr->hptxfsiz = dwc2_readl(hsotg->regs + HPTXFSIZ);
81 	gr->gdfifocfg = dwc2_readl(hsotg->regs + GDFIFOCFG);
82 	for (i = 0; i < MAX_EPS_CHANNELS; i++)
83 		gr->dtxfsiz[i] = dwc2_readl(hsotg->regs + DPTXFSIZN(i));
84 
85 	gr->valid = true;
86 	return 0;
87 }
88 
89 /**
90  * dwc2_restore_global_registers() - Restore controller global registers.
91  * When resuming usb bus, device registers needs to be restored
92  * if controller power were disabled.
93  *
94  * @hsotg: Programming view of the DWC_otg controller
95  */
96 static int dwc2_restore_global_registers(struct dwc2_hsotg *hsotg)
97 {
98 	struct dwc2_gregs_backup *gr;
99 	int i;
100 
101 	dev_dbg(hsotg->dev, "%s\n", __func__);
102 
103 	/* Restore global regs */
104 	gr = &hsotg->gr_backup;
105 	if (!gr->valid) {
106 		dev_err(hsotg->dev, "%s: no global registers to restore\n",
107 			__func__);
108 		return -EINVAL;
109 	}
110 	gr->valid = false;
111 
112 	dwc2_writel(0xffffffff, hsotg->regs + GINTSTS);
113 	dwc2_writel(gr->gotgctl, hsotg->regs + GOTGCTL);
114 	dwc2_writel(gr->gintmsk, hsotg->regs + GINTMSK);
115 	dwc2_writel(gr->gusbcfg, hsotg->regs + GUSBCFG);
116 	dwc2_writel(gr->gahbcfg, hsotg->regs + GAHBCFG);
117 	dwc2_writel(gr->grxfsiz, hsotg->regs + GRXFSIZ);
118 	dwc2_writel(gr->gnptxfsiz, hsotg->regs + GNPTXFSIZ);
119 	dwc2_writel(gr->hptxfsiz, hsotg->regs + HPTXFSIZ);
120 	dwc2_writel(gr->gdfifocfg, hsotg->regs + GDFIFOCFG);
121 	for (i = 0; i < MAX_EPS_CHANNELS; i++)
122 		dwc2_writel(gr->dtxfsiz[i], hsotg->regs + DPTXFSIZN(i));
123 
124 	return 0;
125 }
126 
127 /**
128  * dwc2_exit_hibernation() - Exit controller from Partial Power Down.
129  *
130  * @hsotg: Programming view of the DWC_otg controller
131  * @restore: Controller registers need to be restored
132  */
133 int dwc2_exit_hibernation(struct dwc2_hsotg *hsotg, bool restore)
134 {
135 	u32 pcgcctl;
136 	int ret = 0;
137 
138 	if (!hsotg->params.hibernation)
139 		return -ENOTSUPP;
140 
141 	pcgcctl = dwc2_readl(hsotg->regs + PCGCTL);
142 	pcgcctl &= ~PCGCTL_STOPPCLK;
143 	dwc2_writel(pcgcctl, hsotg->regs + PCGCTL);
144 
145 	pcgcctl = dwc2_readl(hsotg->regs + PCGCTL);
146 	pcgcctl &= ~PCGCTL_PWRCLMP;
147 	dwc2_writel(pcgcctl, hsotg->regs + PCGCTL);
148 
149 	pcgcctl = dwc2_readl(hsotg->regs + PCGCTL);
150 	pcgcctl &= ~PCGCTL_RSTPDWNMODULE;
151 	dwc2_writel(pcgcctl, hsotg->regs + PCGCTL);
152 
153 	udelay(100);
154 	if (restore) {
155 		ret = dwc2_restore_global_registers(hsotg);
156 		if (ret) {
157 			dev_err(hsotg->dev, "%s: failed to restore registers\n",
158 				__func__);
159 			return ret;
160 		}
161 		if (dwc2_is_host_mode(hsotg)) {
162 			ret = dwc2_restore_host_registers(hsotg);
163 			if (ret) {
164 				dev_err(hsotg->dev, "%s: failed to restore host registers\n",
165 					__func__);
166 				return ret;
167 			}
168 		} else {
169 			ret = dwc2_restore_device_registers(hsotg);
170 			if (ret) {
171 				dev_err(hsotg->dev, "%s: failed to restore device registers\n",
172 					__func__);
173 				return ret;
174 			}
175 		}
176 	}
177 
178 	return ret;
179 }
180 
181 /**
182  * dwc2_enter_hibernation() - Put controller in Partial Power Down.
183  *
184  * @hsotg: Programming view of the DWC_otg controller
185  */
186 int dwc2_enter_hibernation(struct dwc2_hsotg *hsotg)
187 {
188 	u32 pcgcctl;
189 	int ret = 0;
190 
191 	if (!hsotg->params.hibernation)
192 		return -ENOTSUPP;
193 
194 	/* Backup all registers */
195 	ret = dwc2_backup_global_registers(hsotg);
196 	if (ret) {
197 		dev_err(hsotg->dev, "%s: failed to backup global registers\n",
198 			__func__);
199 		return ret;
200 	}
201 
202 	if (dwc2_is_host_mode(hsotg)) {
203 		ret = dwc2_backup_host_registers(hsotg);
204 		if (ret) {
205 			dev_err(hsotg->dev, "%s: failed to backup host registers\n",
206 				__func__);
207 			return ret;
208 		}
209 	} else {
210 		ret = dwc2_backup_device_registers(hsotg);
211 		if (ret) {
212 			dev_err(hsotg->dev, "%s: failed to backup device registers\n",
213 				__func__);
214 			return ret;
215 		}
216 	}
217 
218 	/*
219 	 * Clear any pending interrupts since dwc2 will not be able to
220 	 * clear them after entering hibernation.
221 	 */
222 	dwc2_writel(0xffffffff, hsotg->regs + GINTSTS);
223 
224 	/* Put the controller in low power state */
225 	pcgcctl = dwc2_readl(hsotg->regs + PCGCTL);
226 
227 	pcgcctl |= PCGCTL_PWRCLMP;
228 	dwc2_writel(pcgcctl, hsotg->regs + PCGCTL);
229 	ndelay(20);
230 
231 	pcgcctl |= PCGCTL_RSTPDWNMODULE;
232 	dwc2_writel(pcgcctl, hsotg->regs + PCGCTL);
233 	ndelay(20);
234 
235 	pcgcctl |= PCGCTL_STOPPCLK;
236 	dwc2_writel(pcgcctl, hsotg->regs + PCGCTL);
237 
238 	return ret;
239 }
240 
241 /**
242  * dwc2_wait_for_mode() - Waits for the controller mode.
243  * @hsotg:	Programming view of the DWC_otg controller.
244  * @host_mode:	If true, waits for host mode, otherwise device mode.
245  */
246 static void dwc2_wait_for_mode(struct dwc2_hsotg *hsotg,
247 			       bool host_mode)
248 {
249 	ktime_t start;
250 	ktime_t end;
251 	unsigned int timeout = 110;
252 
253 	dev_vdbg(hsotg->dev, "Waiting for %s mode\n",
254 		 host_mode ? "host" : "device");
255 
256 	start = ktime_get();
257 
258 	while (1) {
259 		s64 ms;
260 
261 		if (dwc2_is_host_mode(hsotg) == host_mode) {
262 			dev_vdbg(hsotg->dev, "%s mode set\n",
263 				 host_mode ? "Host" : "Device");
264 			break;
265 		}
266 
267 		end = ktime_get();
268 		ms = ktime_to_ms(ktime_sub(end, start));
269 
270 		if (ms >= (s64)timeout) {
271 			dev_warn(hsotg->dev, "%s: Couldn't set %s mode\n",
272 				 __func__, host_mode ? "host" : "device");
273 			break;
274 		}
275 
276 		usleep_range(1000, 2000);
277 	}
278 }
279 
280 /**
281  * dwc2_iddig_filter_enabled() - Returns true if the IDDIG debounce
282  * filter is enabled.
283  */
284 static bool dwc2_iddig_filter_enabled(struct dwc2_hsotg *hsotg)
285 {
286 	u32 gsnpsid;
287 	u32 ghwcfg4;
288 
289 	if (!dwc2_hw_is_otg(hsotg))
290 		return false;
291 
292 	/* Check if core configuration includes the IDDIG filter. */
293 	ghwcfg4 = dwc2_readl(hsotg->regs + GHWCFG4);
294 	if (!(ghwcfg4 & GHWCFG4_IDDIG_FILT_EN))
295 		return false;
296 
297 	/*
298 	 * Check if the IDDIG debounce filter is bypassed. Available
299 	 * in core version >= 3.10a.
300 	 */
301 	gsnpsid = dwc2_readl(hsotg->regs + GSNPSID);
302 	if (gsnpsid >= DWC2_CORE_REV_3_10a) {
303 		u32 gotgctl = dwc2_readl(hsotg->regs + GOTGCTL);
304 
305 		if (gotgctl & GOTGCTL_DBNCE_FLTR_BYPASS)
306 			return false;
307 	}
308 
309 	return true;
310 }
311 
312 /*
313  * Do core a soft reset of the core.  Be careful with this because it
314  * resets all the internal state machines of the core.
315  */
316 int dwc2_core_reset(struct dwc2_hsotg *hsotg, bool skip_wait)
317 {
318 	u32 greset;
319 	int count = 0;
320 	bool wait_for_host_mode = false;
321 
322 	dev_vdbg(hsotg->dev, "%s()\n", __func__);
323 
324 	/*
325 	 * If the current mode is host, either due to the force mode
326 	 * bit being set (which persists after core reset) or the
327 	 * connector id pin, a core soft reset will temporarily reset
328 	 * the mode to device. A delay from the IDDIG debounce filter
329 	 * will occur before going back to host mode.
330 	 *
331 	 * Determine whether we will go back into host mode after a
332 	 * reset and account for this delay after the reset.
333 	 */
334 	if (dwc2_iddig_filter_enabled(hsotg)) {
335 		u32 gotgctl = dwc2_readl(hsotg->regs + GOTGCTL);
336 		u32 gusbcfg = dwc2_readl(hsotg->regs + GUSBCFG);
337 
338 		if (!(gotgctl & GOTGCTL_CONID_B) ||
339 		    (gusbcfg & GUSBCFG_FORCEHOSTMODE)) {
340 			wait_for_host_mode = true;
341 		}
342 	}
343 
344 	/* Core Soft Reset */
345 	greset = dwc2_readl(hsotg->regs + GRSTCTL);
346 	greset |= GRSTCTL_CSFTRST;
347 	dwc2_writel(greset, hsotg->regs + GRSTCTL);
348 	do {
349 		udelay(1);
350 		greset = dwc2_readl(hsotg->regs + GRSTCTL);
351 		if (++count > 50) {
352 			dev_warn(hsotg->dev,
353 				 "%s() HANG! Soft Reset GRSTCTL=%0x\n",
354 				 __func__, greset);
355 			return -EBUSY;
356 		}
357 	} while (greset & GRSTCTL_CSFTRST);
358 
359 	/* Wait for AHB master IDLE state */
360 	count = 0;
361 	do {
362 		udelay(1);
363 		greset = dwc2_readl(hsotg->regs + GRSTCTL);
364 		if (++count > 50) {
365 			dev_warn(hsotg->dev,
366 				 "%s() HANG! AHB Idle GRSTCTL=%0x\n",
367 				 __func__, greset);
368 			return -EBUSY;
369 		}
370 	} while (!(greset & GRSTCTL_AHBIDLE));
371 
372 	if (wait_for_host_mode && !skip_wait)
373 		dwc2_wait_for_mode(hsotg, true);
374 
375 	return 0;
376 }
377 
378 /*
379  * Force the mode of the controller.
380  *
381  * Forcing the mode is needed for two cases:
382  *
383  * 1) If the dr_mode is set to either HOST or PERIPHERAL we force the
384  * controller to stay in a particular mode regardless of ID pin
385  * changes. We do this usually after a core reset.
386  *
387  * 2) During probe we want to read reset values of the hw
388  * configuration registers that are only available in either host or
389  * device mode. We may need to force the mode if the current mode does
390  * not allow us to access the register in the mode that we want.
391  *
392  * In either case it only makes sense to force the mode if the
393  * controller hardware is OTG capable.
394  *
395  * Checks are done in this function to determine whether doing a force
396  * would be valid or not.
397  *
398  * If a force is done, it requires a IDDIG debounce filter delay if
399  * the filter is configured and enabled. We poll the current mode of
400  * the controller to account for this delay.
401  */
402 static bool dwc2_force_mode(struct dwc2_hsotg *hsotg, bool host)
403 {
404 	u32 gusbcfg;
405 	u32 set;
406 	u32 clear;
407 
408 	dev_dbg(hsotg->dev, "Forcing mode to %s\n", host ? "host" : "device");
409 
410 	/*
411 	 * Force mode has no effect if the hardware is not OTG.
412 	 */
413 	if (!dwc2_hw_is_otg(hsotg))
414 		return false;
415 
416 	/*
417 	 * If dr_mode is either peripheral or host only, there is no
418 	 * need to ever force the mode to the opposite mode.
419 	 */
420 	if (WARN_ON(host && hsotg->dr_mode == USB_DR_MODE_PERIPHERAL))
421 		return false;
422 
423 	if (WARN_ON(!host && hsotg->dr_mode == USB_DR_MODE_HOST))
424 		return false;
425 
426 	gusbcfg = dwc2_readl(hsotg->regs + GUSBCFG);
427 
428 	set = host ? GUSBCFG_FORCEHOSTMODE : GUSBCFG_FORCEDEVMODE;
429 	clear = host ? GUSBCFG_FORCEDEVMODE : GUSBCFG_FORCEHOSTMODE;
430 
431 	gusbcfg &= ~clear;
432 	gusbcfg |= set;
433 	dwc2_writel(gusbcfg, hsotg->regs + GUSBCFG);
434 
435 	dwc2_wait_for_mode(hsotg, host);
436 	return true;
437 }
438 
439 /**
440  * dwc2_clear_force_mode() - Clears the force mode bits.
441  *
442  * After clearing the bits, wait up to 100 ms to account for any
443  * potential IDDIG filter delay. We can't know if we expect this delay
444  * or not because the value of the connector ID status is affected by
445  * the force mode. We only need to call this once during probe if
446  * dr_mode == OTG.
447  */
448 void dwc2_clear_force_mode(struct dwc2_hsotg *hsotg)
449 {
450 	u32 gusbcfg;
451 
452 	gusbcfg = dwc2_readl(hsotg->regs + GUSBCFG);
453 	gusbcfg &= ~GUSBCFG_FORCEHOSTMODE;
454 	gusbcfg &= ~GUSBCFG_FORCEDEVMODE;
455 	dwc2_writel(gusbcfg, hsotg->regs + GUSBCFG);
456 
457 	if (dwc2_iddig_filter_enabled(hsotg))
458 		msleep(100);
459 }
460 
461 /*
462  * Sets or clears force mode based on the dr_mode parameter.
463  */
464 void dwc2_force_dr_mode(struct dwc2_hsotg *hsotg)
465 {
466 	bool ret;
467 
468 	switch (hsotg->dr_mode) {
469 	case USB_DR_MODE_HOST:
470 		ret = dwc2_force_mode(hsotg, true);
471 		/*
472 		 * NOTE: This is required for some rockchip soc based
473 		 * platforms on their host-only dwc2.
474 		 */
475 		if (!ret)
476 			msleep(50);
477 
478 		break;
479 	case USB_DR_MODE_PERIPHERAL:
480 		dwc2_force_mode(hsotg, false);
481 		break;
482 	case USB_DR_MODE_OTG:
483 		dwc2_clear_force_mode(hsotg);
484 		break;
485 	default:
486 		dev_warn(hsotg->dev, "%s() Invalid dr_mode=%d\n",
487 			 __func__, hsotg->dr_mode);
488 		break;
489 	}
490 }
491 
492 /*
493  * Do core a soft reset of the core.  Be careful with this because it
494  * resets all the internal state machines of the core.
495  *
496  * Additionally this will apply force mode as per the hsotg->dr_mode
497  * parameter.
498  */
499 int dwc2_core_reset_and_force_dr_mode(struct dwc2_hsotg *hsotg)
500 {
501 	int retval;
502 
503 	retval = dwc2_core_reset(hsotg, false);
504 	if (retval)
505 		return retval;
506 
507 	dwc2_force_dr_mode(hsotg);
508 	return 0;
509 }
510 
511 /**
512  * dwc2_dump_host_registers() - Prints the host registers
513  *
514  * @hsotg: Programming view of DWC_otg controller
515  *
516  * NOTE: This function will be removed once the peripheral controller code
517  * is integrated and the driver is stable
518  */
519 void dwc2_dump_host_registers(struct dwc2_hsotg *hsotg)
520 {
521 #ifdef DEBUG
522 	u32 __iomem *addr;
523 	int i;
524 
525 	dev_dbg(hsotg->dev, "Host Global Registers\n");
526 	addr = hsotg->regs + HCFG;
527 	dev_dbg(hsotg->dev, "HCFG	 @0x%08lX : 0x%08X\n",
528 		(unsigned long)addr, dwc2_readl(addr));
529 	addr = hsotg->regs + HFIR;
530 	dev_dbg(hsotg->dev, "HFIR	 @0x%08lX : 0x%08X\n",
531 		(unsigned long)addr, dwc2_readl(addr));
532 	addr = hsotg->regs + HFNUM;
533 	dev_dbg(hsotg->dev, "HFNUM	 @0x%08lX : 0x%08X\n",
534 		(unsigned long)addr, dwc2_readl(addr));
535 	addr = hsotg->regs + HPTXSTS;
536 	dev_dbg(hsotg->dev, "HPTXSTS	 @0x%08lX : 0x%08X\n",
537 		(unsigned long)addr, dwc2_readl(addr));
538 	addr = hsotg->regs + HAINT;
539 	dev_dbg(hsotg->dev, "HAINT	 @0x%08lX : 0x%08X\n",
540 		(unsigned long)addr, dwc2_readl(addr));
541 	addr = hsotg->regs + HAINTMSK;
542 	dev_dbg(hsotg->dev, "HAINTMSK	 @0x%08lX : 0x%08X\n",
543 		(unsigned long)addr, dwc2_readl(addr));
544 	if (hsotg->params.dma_desc_enable) {
545 		addr = hsotg->regs + HFLBADDR;
546 		dev_dbg(hsotg->dev, "HFLBADDR @0x%08lX : 0x%08X\n",
547 			(unsigned long)addr, dwc2_readl(addr));
548 	}
549 
550 	addr = hsotg->regs + HPRT0;
551 	dev_dbg(hsotg->dev, "HPRT0	 @0x%08lX : 0x%08X\n",
552 		(unsigned long)addr, dwc2_readl(addr));
553 
554 	for (i = 0; i < hsotg->params.host_channels; i++) {
555 		dev_dbg(hsotg->dev, "Host Channel %d Specific Registers\n", i);
556 		addr = hsotg->regs + HCCHAR(i);
557 		dev_dbg(hsotg->dev, "HCCHAR	 @0x%08lX : 0x%08X\n",
558 			(unsigned long)addr, dwc2_readl(addr));
559 		addr = hsotg->regs + HCSPLT(i);
560 		dev_dbg(hsotg->dev, "HCSPLT	 @0x%08lX : 0x%08X\n",
561 			(unsigned long)addr, dwc2_readl(addr));
562 		addr = hsotg->regs + HCINT(i);
563 		dev_dbg(hsotg->dev, "HCINT	 @0x%08lX : 0x%08X\n",
564 			(unsigned long)addr, dwc2_readl(addr));
565 		addr = hsotg->regs + HCINTMSK(i);
566 		dev_dbg(hsotg->dev, "HCINTMSK	 @0x%08lX : 0x%08X\n",
567 			(unsigned long)addr, dwc2_readl(addr));
568 		addr = hsotg->regs + HCTSIZ(i);
569 		dev_dbg(hsotg->dev, "HCTSIZ	 @0x%08lX : 0x%08X\n",
570 			(unsigned long)addr, dwc2_readl(addr));
571 		addr = hsotg->regs + HCDMA(i);
572 		dev_dbg(hsotg->dev, "HCDMA	 @0x%08lX : 0x%08X\n",
573 			(unsigned long)addr, dwc2_readl(addr));
574 		if (hsotg->params.dma_desc_enable) {
575 			addr = hsotg->regs + HCDMAB(i);
576 			dev_dbg(hsotg->dev, "HCDMAB	 @0x%08lX : 0x%08X\n",
577 				(unsigned long)addr, dwc2_readl(addr));
578 		}
579 	}
580 #endif
581 }
582 
583 /**
584  * dwc2_dump_global_registers() - Prints the core global registers
585  *
586  * @hsotg: Programming view of DWC_otg controller
587  *
588  * NOTE: This function will be removed once the peripheral controller code
589  * is integrated and the driver is stable
590  */
591 void dwc2_dump_global_registers(struct dwc2_hsotg *hsotg)
592 {
593 #ifdef DEBUG
594 	u32 __iomem *addr;
595 
596 	dev_dbg(hsotg->dev, "Core Global Registers\n");
597 	addr = hsotg->regs + GOTGCTL;
598 	dev_dbg(hsotg->dev, "GOTGCTL	 @0x%08lX : 0x%08X\n",
599 		(unsigned long)addr, dwc2_readl(addr));
600 	addr = hsotg->regs + GOTGINT;
601 	dev_dbg(hsotg->dev, "GOTGINT	 @0x%08lX : 0x%08X\n",
602 		(unsigned long)addr, dwc2_readl(addr));
603 	addr = hsotg->regs + GAHBCFG;
604 	dev_dbg(hsotg->dev, "GAHBCFG	 @0x%08lX : 0x%08X\n",
605 		(unsigned long)addr, dwc2_readl(addr));
606 	addr = hsotg->regs + GUSBCFG;
607 	dev_dbg(hsotg->dev, "GUSBCFG	 @0x%08lX : 0x%08X\n",
608 		(unsigned long)addr, dwc2_readl(addr));
609 	addr = hsotg->regs + GRSTCTL;
610 	dev_dbg(hsotg->dev, "GRSTCTL	 @0x%08lX : 0x%08X\n",
611 		(unsigned long)addr, dwc2_readl(addr));
612 	addr = hsotg->regs + GINTSTS;
613 	dev_dbg(hsotg->dev, "GINTSTS	 @0x%08lX : 0x%08X\n",
614 		(unsigned long)addr, dwc2_readl(addr));
615 	addr = hsotg->regs + GINTMSK;
616 	dev_dbg(hsotg->dev, "GINTMSK	 @0x%08lX : 0x%08X\n",
617 		(unsigned long)addr, dwc2_readl(addr));
618 	addr = hsotg->regs + GRXSTSR;
619 	dev_dbg(hsotg->dev, "GRXSTSR	 @0x%08lX : 0x%08X\n",
620 		(unsigned long)addr, dwc2_readl(addr));
621 	addr = hsotg->regs + GRXFSIZ;
622 	dev_dbg(hsotg->dev, "GRXFSIZ	 @0x%08lX : 0x%08X\n",
623 		(unsigned long)addr, dwc2_readl(addr));
624 	addr = hsotg->regs + GNPTXFSIZ;
625 	dev_dbg(hsotg->dev, "GNPTXFSIZ	 @0x%08lX : 0x%08X\n",
626 		(unsigned long)addr, dwc2_readl(addr));
627 	addr = hsotg->regs + GNPTXSTS;
628 	dev_dbg(hsotg->dev, "GNPTXSTS	 @0x%08lX : 0x%08X\n",
629 		(unsigned long)addr, dwc2_readl(addr));
630 	addr = hsotg->regs + GI2CCTL;
631 	dev_dbg(hsotg->dev, "GI2CCTL	 @0x%08lX : 0x%08X\n",
632 		(unsigned long)addr, dwc2_readl(addr));
633 	addr = hsotg->regs + GPVNDCTL;
634 	dev_dbg(hsotg->dev, "GPVNDCTL	 @0x%08lX : 0x%08X\n",
635 		(unsigned long)addr, dwc2_readl(addr));
636 	addr = hsotg->regs + GGPIO;
637 	dev_dbg(hsotg->dev, "GGPIO	 @0x%08lX : 0x%08X\n",
638 		(unsigned long)addr, dwc2_readl(addr));
639 	addr = hsotg->regs + GUID;
640 	dev_dbg(hsotg->dev, "GUID	 @0x%08lX : 0x%08X\n",
641 		(unsigned long)addr, dwc2_readl(addr));
642 	addr = hsotg->regs + GSNPSID;
643 	dev_dbg(hsotg->dev, "GSNPSID	 @0x%08lX : 0x%08X\n",
644 		(unsigned long)addr, dwc2_readl(addr));
645 	addr = hsotg->regs + GHWCFG1;
646 	dev_dbg(hsotg->dev, "GHWCFG1	 @0x%08lX : 0x%08X\n",
647 		(unsigned long)addr, dwc2_readl(addr));
648 	addr = hsotg->regs + GHWCFG2;
649 	dev_dbg(hsotg->dev, "GHWCFG2	 @0x%08lX : 0x%08X\n",
650 		(unsigned long)addr, dwc2_readl(addr));
651 	addr = hsotg->regs + GHWCFG3;
652 	dev_dbg(hsotg->dev, "GHWCFG3	 @0x%08lX : 0x%08X\n",
653 		(unsigned long)addr, dwc2_readl(addr));
654 	addr = hsotg->regs + GHWCFG4;
655 	dev_dbg(hsotg->dev, "GHWCFG4	 @0x%08lX : 0x%08X\n",
656 		(unsigned long)addr, dwc2_readl(addr));
657 	addr = hsotg->regs + GLPMCFG;
658 	dev_dbg(hsotg->dev, "GLPMCFG	 @0x%08lX : 0x%08X\n",
659 		(unsigned long)addr, dwc2_readl(addr));
660 	addr = hsotg->regs + GPWRDN;
661 	dev_dbg(hsotg->dev, "GPWRDN	 @0x%08lX : 0x%08X\n",
662 		(unsigned long)addr, dwc2_readl(addr));
663 	addr = hsotg->regs + GDFIFOCFG;
664 	dev_dbg(hsotg->dev, "GDFIFOCFG	 @0x%08lX : 0x%08X\n",
665 		(unsigned long)addr, dwc2_readl(addr));
666 	addr = hsotg->regs + HPTXFSIZ;
667 	dev_dbg(hsotg->dev, "HPTXFSIZ	 @0x%08lX : 0x%08X\n",
668 		(unsigned long)addr, dwc2_readl(addr));
669 
670 	addr = hsotg->regs + PCGCTL;
671 	dev_dbg(hsotg->dev, "PCGCTL	 @0x%08lX : 0x%08X\n",
672 		(unsigned long)addr, dwc2_readl(addr));
673 #endif
674 }
675 
676 /**
677  * dwc2_flush_tx_fifo() - Flushes a Tx FIFO
678  *
679  * @hsotg: Programming view of DWC_otg controller
680  * @num:   Tx FIFO to flush
681  */
682 void dwc2_flush_tx_fifo(struct dwc2_hsotg *hsotg, const int num)
683 {
684 	u32 greset;
685 	int count = 0;
686 
687 	dev_vdbg(hsotg->dev, "Flush Tx FIFO %d\n", num);
688 
689 	greset = GRSTCTL_TXFFLSH;
690 	greset |= num << GRSTCTL_TXFNUM_SHIFT & GRSTCTL_TXFNUM_MASK;
691 	dwc2_writel(greset, hsotg->regs + GRSTCTL);
692 
693 	do {
694 		greset = dwc2_readl(hsotg->regs + GRSTCTL);
695 		if (++count > 10000) {
696 			dev_warn(hsotg->dev,
697 				 "%s() HANG! GRSTCTL=%0x GNPTXSTS=0x%08x\n",
698 				 __func__, greset,
699 				 dwc2_readl(hsotg->regs + GNPTXSTS));
700 			break;
701 		}
702 		udelay(1);
703 	} while (greset & GRSTCTL_TXFFLSH);
704 
705 	/* Wait for at least 3 PHY Clocks */
706 	udelay(1);
707 }
708 
709 /**
710  * dwc2_flush_rx_fifo() - Flushes the Rx FIFO
711  *
712  * @hsotg: Programming view of DWC_otg controller
713  */
714 void dwc2_flush_rx_fifo(struct dwc2_hsotg *hsotg)
715 {
716 	u32 greset;
717 	int count = 0;
718 
719 	dev_vdbg(hsotg->dev, "%s()\n", __func__);
720 
721 	greset = GRSTCTL_RXFFLSH;
722 	dwc2_writel(greset, hsotg->regs + GRSTCTL);
723 
724 	do {
725 		greset = dwc2_readl(hsotg->regs + GRSTCTL);
726 		if (++count > 10000) {
727 			dev_warn(hsotg->dev, "%s() HANG! GRSTCTL=%0x\n",
728 				 __func__, greset);
729 			break;
730 		}
731 		udelay(1);
732 	} while (greset & GRSTCTL_RXFFLSH);
733 
734 	/* Wait for at least 3 PHY Clocks */
735 	udelay(1);
736 }
737 
738 /*
739  * Forces either host or device mode if the controller is not
740  * currently in that mode.
741  *
742  * Returns true if the mode was forced.
743  */
744 bool dwc2_force_mode_if_needed(struct dwc2_hsotg *hsotg, bool host)
745 {
746 	if (host && dwc2_is_host_mode(hsotg))
747 		return false;
748 	else if (!host && dwc2_is_device_mode(hsotg))
749 		return false;
750 
751 	return dwc2_force_mode(hsotg, host);
752 }
753 
754 bool dwc2_is_controller_alive(struct dwc2_hsotg *hsotg)
755 {
756 	if (dwc2_readl(hsotg->regs + GSNPSID) == 0xffffffff)
757 		return false;
758 	else
759 		return true;
760 }
761 
762 /**
763  * dwc2_enable_global_interrupts() - Enables the controller's Global
764  * Interrupt in the AHB Config register
765  *
766  * @hsotg: Programming view of DWC_otg controller
767  */
768 void dwc2_enable_global_interrupts(struct dwc2_hsotg *hsotg)
769 {
770 	u32 ahbcfg = dwc2_readl(hsotg->regs + GAHBCFG);
771 
772 	ahbcfg |= GAHBCFG_GLBL_INTR_EN;
773 	dwc2_writel(ahbcfg, hsotg->regs + GAHBCFG);
774 }
775 
776 /**
777  * dwc2_disable_global_interrupts() - Disables the controller's Global
778  * Interrupt in the AHB Config register
779  *
780  * @hsotg: Programming view of DWC_otg controller
781  */
782 void dwc2_disable_global_interrupts(struct dwc2_hsotg *hsotg)
783 {
784 	u32 ahbcfg = dwc2_readl(hsotg->regs + GAHBCFG);
785 
786 	ahbcfg &= ~GAHBCFG_GLBL_INTR_EN;
787 	dwc2_writel(ahbcfg, hsotg->regs + GAHBCFG);
788 }
789 
790 /* Returns the controller's GHWCFG2.OTG_MODE. */
791 unsigned int dwc2_op_mode(struct dwc2_hsotg *hsotg)
792 {
793 	u32 ghwcfg2 = dwc2_readl(hsotg->regs + GHWCFG2);
794 
795 	return (ghwcfg2 & GHWCFG2_OP_MODE_MASK) >>
796 		GHWCFG2_OP_MODE_SHIFT;
797 }
798 
799 /* Returns true if the controller is capable of DRD. */
800 bool dwc2_hw_is_otg(struct dwc2_hsotg *hsotg)
801 {
802 	unsigned int op_mode = dwc2_op_mode(hsotg);
803 
804 	return (op_mode == GHWCFG2_OP_MODE_HNP_SRP_CAPABLE) ||
805 		(op_mode == GHWCFG2_OP_MODE_SRP_ONLY_CAPABLE) ||
806 		(op_mode == GHWCFG2_OP_MODE_NO_HNP_SRP_CAPABLE);
807 }
808 
809 /* Returns true if the controller is host-only. */
810 bool dwc2_hw_is_host(struct dwc2_hsotg *hsotg)
811 {
812 	unsigned int op_mode = dwc2_op_mode(hsotg);
813 
814 	return (op_mode == GHWCFG2_OP_MODE_SRP_CAPABLE_HOST) ||
815 		(op_mode == GHWCFG2_OP_MODE_NO_SRP_CAPABLE_HOST);
816 }
817 
818 /* Returns true if the controller is device-only. */
819 bool dwc2_hw_is_device(struct dwc2_hsotg *hsotg)
820 {
821 	unsigned int op_mode = dwc2_op_mode(hsotg);
822 
823 	return (op_mode == GHWCFG2_OP_MODE_SRP_CAPABLE_DEVICE) ||
824 		(op_mode == GHWCFG2_OP_MODE_NO_SRP_CAPABLE_DEVICE);
825 }
826 
827 MODULE_DESCRIPTION("DESIGNWARE HS OTG Core");
828 MODULE_AUTHOR("Synopsys, Inc.");
829 MODULE_LICENSE("Dual BSD/GPL");
830