xref: /freebsd/sys/dev/uart/uart_dev_mvebu.c (revision 0b57cec536236d46e3dba9bd041533462f33dbb7)
1 /*-
2  * Copyright (c) 2017 Semihalf.
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 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/bus.h>
32 #include <sys/conf.h>
33 #include <sys/kernel.h>
34 #include <sys/sysctl.h>
35 #include <sys/systm.h>
36 
37 #include <machine/bus.h>
38 
39 #include <dev/ofw/ofw_bus_subr.h>
40 #include <dev/uart/uart.h>
41 #include <dev/uart/uart_bus.h>
42 #include <dev/uart/uart_cpu.h>
43 #include <dev/uart/uart_cpu_fdt.h>
44 
45 #include "uart_if.h"
46 
47 #define	UART_RBR		0x00		/* Receiver Buffer */
48 #define	RBR_BRK_DET		(1 << 15)	/* Break Detect */
49 #define	RBR_FRM_ERR_DET		(1 << 14)	/* Frame Error Detect */
50 #define	RBR_PAR_ERR_DET		(1 << 13)	/* Parity Error Detect */
51 #define	RBR_OVR_ERR_DET		(1 << 12)	/* Overrun Error */
52 
53 #define	UART_TSH		0x04		/* Transmitter Holding Register */
54 
55 #define	UART_CTRL		0x08		/* Control Register */
56 #define	CTRL_SOFT_RST		(1 << 31)	/* Soft Reset */
57 #define	CTRL_TX_FIFO_RST	(1 << 15)	/* TX FIFO Reset */
58 #define	CTRL_RX_FIFO_RST	(1 << 14)	/* RX FIFO Reset */
59 #define	CTRL_ST_MIRR_EN		(1 << 13)	/* Status Mirror Enable */
60 #define	CTRL_LPBK_EN		(1 << 12)	/* Loopback Mode Enable */
61 #define	CTRL_SND_BRK_SEQ	(1 << 11)	/* Send Break Sequence */
62 #define	CTRL_PAR_EN		(1 << 10)	/* Parity Enable */
63 #define	CTRL_TWO_STOP		(1 << 9)	/* Two Stop Bits */
64 #define	CTRL_TX_HALF_INT	(1 << 8)	/* TX Half-Full Interrupt Enable */
65 #define	CTRL_RX_HALF_INT	(1 << 7)	/* RX Half-Full Interrupt Enable */
66 #define	CTRL_TX_EMPT_INT	(1 << 6)	/* TX Empty Interrupt Enable */
67 #define	CTRL_TX_RDY_INT		(1 << 5)	/* TX Ready Interrupt Enable */
68 #define	CTRL_RX_RDY_INT		(1 << 4)	/* RX Ready Interrupt Enable */
69 #define	CTRL_BRK_DET_INT	(1 << 3)	/* Break Detect Interrupt Enable */
70 #define	CTRL_FRM_ERR_INT	(1 << 2)	/* Frame Error Interrupt Enable */
71 #define	CTRL_PAR_ERR_INT	(1 << 1)	/* Parity Error Interrupt Enable */
72 #define	CTRL_OVR_ERR_INT	(1 << 0)	/* Overrun Error Interrupt Enable */
73 #define	CTRL_INTR_MASK		0x1ff
74 #define	CTRL_TX_IDLE_INT	CTRL_TX_RDY_INT
75 #define	CTRL_IPEND_MASK		(CTRL_OVR_ERR_INT | CTRL_BRK_DET_INT | \
76     CTRL_RX_RDY_INT)
77 
78 #define	UART_STAT		0x0c		/* Status Register */
79 #define	STAT_TX_FIFO_EMPT	(1 << 13)	/* TX FIFO Empty */
80 #define	STAT_RX_FIFO_EMPT	(1 << 12)	/* RX FIFO Empty */
81 #define	STAT_TX_FIFO_FULL	(1 << 11)	/* TX FIFO Full */
82 #define	STAT_TX_FIFO_HALF	(1 << 10)	/* TX FIFO Half Full */
83 #define	STAT_RX_TOGL		(1 << 9)	/* RX Toogled */
84 #define	STAT_RX_FIFO_FULL	(1 << 8)	/* RX FIFO Full */
85 #define	STAT_RX_FIFO_HALF	(1 << 7)	/* RX FIFO Half Full */
86 #define	STAT_TX_EMPT		(1 << 6)	/* TX Empty */
87 #define	STAT_TX_RDY		(1 << 5)	/* TX Ready */
88 #define	STAT_RX_RDY		(1 << 4)	/* RX Ready */
89 #define	STAT_BRK_DET		(1 << 3)	/* Break Detect */
90 #define	STAT_FRM_ERR		(1 << 2)	/* Frame Error */
91 #define	STAT_PAR_ERR		(1 << 1)	/* Parity Error */
92 #define	STAT_OVR_ERR		(1 << 0)	/* Overrun Error */
93 #define	STAT_TX_IDLE		STAT_TX_RDY
94 #define	STAT_TRANS_MASK		(STAT_OVR_ERR | STAT_BRK_DET | STAT_RX_RDY)
95 
96 #define	UART_CCR		0x10		/* Clock Control Register */
97 #define	CCR_BAUDRATE_DIV	0x3ff		/* Baud Rate Divisor */
98 
99 #define	DEFAULT_RCLK		25804800
100 #define	ONE_FRAME_TIME		87
101 
102 #define	stat_ipend_trans(i) (			\
103 	    (i & STAT_OVR_ERR) << 16 |		\
104 	    (i & STAT_BRK_DET) << 14 |		\
105 	    (i & STAT_RX_RDY) << 14)
106 
107 /*
108  * For debugging purposes
109  */
110 #if 0
111 #ifdef EARLY_PRINTF
112 #if defined(SOCDEV_PA) && defined(SOCDEV_VA)
113 #define	UART_REG_OFFSET 0x12000
114 static void
115 uart_mvebu_early_putc(int c)
116 {
117 	volatile uint32_t *tsh;
118 	volatile uint32_t *stat;
119 
120 	tsh = (uint32_t *)(SOCDEV_VA + UART_REG_OFFSET + UART_TSH);
121 	stat = (uint32_t *)(SOCDEV_VA + UART_REG_OFFSET + UART_STAT);
122 
123 	while(!(*stat & STAT_TX_RDY))
124 		;
125 
126 	*tsh = c & 0xff;
127 }
128 
129 early_putc_t *early_putc = uart_mvebu_early_putc;
130 #endif
131 #endif
132 #endif
133 
134 /*
135  * Low-level UART interface.
136  */
137 static int uart_mvebu_probe(struct uart_bas *);
138 static void uart_mvebu_init(struct uart_bas *, int, int, int, int);
139 static void uart_mvebu_putc(struct uart_bas *, int);
140 static int uart_mvebu_rxready(struct uart_bas *);
141 static int uart_mvebu_getc(struct uart_bas *, struct mtx *);
142 
143 static struct uart_ops uart_mvebu_ops = {
144 	.probe = uart_mvebu_probe,
145 	.init = uart_mvebu_init,
146 	.term = NULL,
147 	.putc = uart_mvebu_putc,
148 	.rxready = uart_mvebu_rxready,
149 	.getc = uart_mvebu_getc,
150 };
151 
152 static int
153 uart_mvebu_probe(struct uart_bas *bas)
154 {
155 
156 	return (0);
157 }
158 
159 static int
160 uart_mvebu_divisor(int rclk, int baudrate)
161 {
162 	int divisor;
163 
164 	if (baudrate == 0)
165 		return (0);
166 
167 	divisor = (rclk >> 4) / baudrate;
168 	if (divisor <= 1 || divisor >= 1024)
169 		return (0);
170 
171 	return (divisor);
172 }
173 
174 static int
175 uart_mvebu_param(struct uart_bas *bas, int baudrate, int databits, int stopbits,
176     int parity)
177 {
178 	uint32_t ctrl = 0;
179 	uint32_t ccr;
180 	int divisor, ret = 0;
181 
182 	/* Reset UART */
183 	ctrl = uart_getreg(bas, UART_CTRL);
184 	uart_setreg(bas, UART_CTRL, ctrl | CTRL_TX_FIFO_RST | CTRL_RX_FIFO_RST |
185 	    CTRL_LPBK_EN);
186 	uart_barrier(bas);
187 
188 	switch (stopbits) {
189 	case 2:
190 		ctrl |= CTRL_TWO_STOP;
191 		break;
192 	case 1:
193 	default:
194 		ctrl &=~ CTRL_TWO_STOP;
195 	}
196 
197 	switch (parity) {
198 	case 3: /* Even parity bit */
199 		ctrl |= CTRL_PAR_EN;
200 		break;
201 	default:
202 		ctrl &=~ CTRL_PAR_EN;
203 	}
204 
205 	/* Set baudrate. */
206 	if (baudrate > 0) {
207 		divisor = uart_mvebu_divisor(bas->rclk, baudrate);
208 		if (divisor == 0) {
209 			ret = EINVAL;
210 		} else {
211 			ccr = uart_getreg(bas, UART_CCR);
212 			ccr &=~CCR_BAUDRATE_DIV;
213 
214 			uart_setreg(bas, UART_CCR, ccr | divisor);
215 			uart_barrier(bas);
216 		}
217 	}
218 
219 	/* Set mirroring of status bits */
220 	ctrl |= CTRL_ST_MIRR_EN;
221 
222 	uart_setreg(bas, UART_CTRL, ctrl);
223 	uart_barrier(bas);
224 
225 	return (ret);
226 }
227 
228 static void
229 uart_mvebu_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
230     int parity)
231 {
232 	/* Set default frequency */
233 	bas->rclk = DEFAULT_RCLK;
234 
235 	/* Mask interrupts */
236 	uart_setreg(bas, UART_CTRL, uart_getreg(bas, UART_CTRL) &
237 	    ~CTRL_INTR_MASK);
238 	uart_barrier(bas);
239 
240 	uart_mvebu_param(bas, baudrate, databits, stopbits, parity);
241 }
242 
243 static void
244 uart_mvebu_putc(struct uart_bas *bas, int c)
245 {
246 	while (uart_getreg(bas, UART_STAT) & STAT_TX_FIFO_FULL)
247 		;
248 	uart_setreg(bas, UART_TSH, c & 0xff);
249 }
250 
251 static int
252 uart_mvebu_rxready(struct uart_bas *bas)
253 {
254 	if (uart_getreg(bas, UART_STAT) & STAT_RX_RDY)
255 		return 1;
256 	return 0;
257 }
258 
259 static int
260 uart_mvebu_getc(struct uart_bas *bas, struct mtx *hwmtx)
261 {
262 	int c;
263 
264 	uart_lock(hwmtx);
265 	while (!(uart_getreg(bas, UART_STAT) & STAT_RX_RDY))
266 		;
267 
268 	c = uart_getreg(bas, UART_RBR) & 0xff;
269 	uart_unlock(hwmtx);
270 
271 	return c;
272 }
273 
274 /*
275  * UART driver methods implementation.
276  */
277 struct uart_mvebu_softc {
278 	struct uart_softc base;
279 	uint16_t intrm;
280 };
281 
282 static int uart_mvebu_bus_attach(struct uart_softc *);
283 static int uart_mvebu_bus_detach(struct uart_softc *);
284 static int uart_mvebu_bus_flush(struct uart_softc *, int);
285 static int uart_mvebu_bus_getsig(struct uart_softc *);
286 static int uart_mvebu_bus_ioctl(struct uart_softc *, int, intptr_t);
287 static int uart_mvebu_bus_ipend(struct uart_softc *);
288 static int uart_mvebu_bus_param(struct uart_softc *, int, int, int, int);
289 static int uart_mvebu_bus_probe(struct uart_softc *);
290 static int uart_mvebu_bus_receive(struct uart_softc *);
291 static int uart_mvebu_bus_setsig(struct uart_softc *, int);
292 static int uart_mvebu_bus_transmit(struct uart_softc *);
293 static void uart_mvebu_bus_grab(struct uart_softc *);
294 static void uart_mvebu_bus_ungrab(struct uart_softc *);
295 
296 static kobj_method_t uart_mvebu_methods[] = {
297 	KOBJMETHOD(uart_attach,		uart_mvebu_bus_attach),
298 	KOBJMETHOD(uart_detach,		uart_mvebu_bus_detach),
299 	KOBJMETHOD(uart_flush,		uart_mvebu_bus_flush),
300 	KOBJMETHOD(uart_getsig,		uart_mvebu_bus_getsig),
301 	KOBJMETHOD(uart_ioctl,		uart_mvebu_bus_ioctl),
302 	KOBJMETHOD(uart_ipend,		uart_mvebu_bus_ipend),
303 	KOBJMETHOD(uart_param,		uart_mvebu_bus_param),
304 	KOBJMETHOD(uart_probe,		uart_mvebu_bus_probe),
305 	KOBJMETHOD(uart_receive,	uart_mvebu_bus_receive),
306 	KOBJMETHOD(uart_setsig,		uart_mvebu_bus_setsig),
307 	KOBJMETHOD(uart_transmit,	uart_mvebu_bus_transmit),
308 	KOBJMETHOD(uart_grab,		uart_mvebu_bus_grab),
309 	KOBJMETHOD(uart_ungrab,		uart_mvebu_bus_ungrab),
310 	{ 0, 0 }
311 };
312 
313 struct uart_class uart_mvebu_class = {
314 	"mvebu-uart",
315 	uart_mvebu_methods,
316 	sizeof(struct uart_mvebu_softc),
317 	.uc_ops = &uart_mvebu_ops,
318 	.uc_range = 0x14,
319 	.uc_rclk = DEFAULT_RCLK,
320 	.uc_rshift = 0,
321 	.uc_riowidth = 4
322 };
323 
324 static struct ofw_compat_data compat_data[] = {
325 	{"marvell,armada-3700-uart",	(uintptr_t)&uart_mvebu_class},
326 	{NULL,				(uintptr_t)NULL},
327 };
328 UART_FDT_CLASS_AND_DEVICE(compat_data);
329 
330 static int
331 uart_mvebu_bus_attach(struct uart_softc *sc)
332 {
333 	struct uart_bas *bas;
334 	int ctrl;
335 
336 	bas = &sc->sc_bas;
337 	uart_lock(sc->sc_hwmtx);
338 
339 	ctrl = uart_getreg(bas, UART_CTRL);
340 
341 	/* Enable interrupts */
342 	ctrl &=~ CTRL_INTR_MASK;
343 	ctrl |= CTRL_IPEND_MASK;
344 
345 	/* Set interrupts */
346 	uart_setreg(bas, UART_CTRL, ctrl);
347 	uart_barrier(bas);
348 
349 	uart_unlock(sc->sc_hwmtx);
350 
351 	return (0);
352 }
353 
354 static int
355 uart_mvebu_bus_detach(struct uart_softc *sc)
356 {
357 
358 	return (0);
359 }
360 
361 static int
362 uart_mvebu_bus_flush(struct uart_softc *sc, int what)
363 {
364 	struct uart_bas *bas;
365 	int ctrl, ret = 0;
366 
367 	bas = &sc->sc_bas;
368 	uart_lock(sc->sc_hwmtx);
369 	ctrl = uart_getreg(bas, UART_CTRL);
370 
371 	switch (what) {
372 	case UART_FLUSH_RECEIVER:
373 		uart_setreg(bas, UART_CTRL, ctrl | CTRL_RX_FIFO_RST);
374 		uart_barrier(bas);
375 		break;
376 
377 	case UART_FLUSH_TRANSMITTER:
378 		uart_setreg(bas, UART_CTRL, ctrl | CTRL_TX_FIFO_RST);
379 		uart_barrier(bas);
380 		break;
381 
382 	default:
383 		ret = EINVAL;
384 		break;
385 	}
386 
387 	/* Back to normal operation */
388 	if (!ret) {
389 		uart_setreg(bas, UART_CTRL, ctrl);
390 		uart_barrier(bas);
391 	}
392 
393 	uart_unlock(sc->sc_hwmtx);
394 	return (ret);
395 }
396 
397 static int
398 uart_mvebu_bus_getsig(struct uart_softc *sc)
399 {
400 
401 	return (0);
402 }
403 
404 static int
405 uart_mvebu_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
406 {
407 	struct uart_bas *bas;
408 	int ctrl, ret = 0;
409 	int divisor, baudrate;
410 
411 	bas = &sc->sc_bas;
412 	uart_lock(sc->sc_hwmtx);
413 	switch (request) {
414 	case UART_IOCTL_BREAK:
415 		ctrl = uart_getreg(bas, UART_CTRL);
416 		if (data)
417 			ctrl |= CTRL_SND_BRK_SEQ;
418 		else
419 			ctrl &=~ CTRL_SND_BRK_SEQ;
420 		uart_setreg(bas, UART_CTRL, ctrl);
421 		uart_barrier(bas);
422 		break;
423 
424 	case UART_IOCTL_BAUD:
425 		divisor = uart_getreg(bas, UART_CCR) & CCR_BAUDRATE_DIV;
426 		baudrate = bas->rclk/(divisor * 16);
427 		*(int *)data = baudrate;
428 		break;
429 
430 	default:
431 		ret = ENOTTY;
432 		break;
433 	}
434 	uart_unlock(sc->sc_hwmtx);
435 
436 	return (ret);
437 }
438 
439 static int
440 uart_mvebu_bus_ipend(struct uart_softc *sc)
441 {
442 	struct uart_bas *bas;
443 	int ipend, ctrl, ret = 0;
444 
445 	bas = &sc->sc_bas;
446 	uart_lock(sc->sc_hwmtx);
447 	ipend = uart_getreg(bas, UART_STAT);
448 	ctrl = uart_getreg(bas, UART_CTRL);
449 
450 	if (((ipend & STAT_TX_IDLE) == STAT_TX_IDLE) &&
451 	    (ctrl & CTRL_TX_IDLE_INT) == CTRL_TX_IDLE_INT) {
452 		/* Disable TX IDLE Interrupt generation */
453 		uart_setreg(bas, UART_CTRL, ctrl & ~CTRL_TX_IDLE_INT);
454 		uart_barrier(bas);
455 
456 		/* SER_INT_TXIDLE means empty TX FIFO. Wait until it cleans */
457 		while(!(uart_getreg(bas, UART_STAT) & STAT_TX_FIFO_EMPT))
458 			DELAY(ONE_FRAME_TIME/2);
459 
460 		ret |= SER_INT_TXIDLE;
461 	}
462 
463 	ret |= stat_ipend_trans(ipend & STAT_TRANS_MASK);
464 
465 	uart_unlock(sc->sc_hwmtx);
466 
467 	return (ret);
468 }
469 
470 static int
471 uart_mvebu_bus_param(struct uart_softc *sc, int baudrate, int databits,
472     int stopbits, int parity)
473 {
474 	int ret;
475 
476 	uart_lock(sc->sc_hwmtx);
477 	ret = uart_mvebu_param(&sc->sc_bas, baudrate, databits, stopbits, parity);
478 	uart_unlock(sc->sc_hwmtx);
479 
480 	return (ret);
481 }
482 
483 static int
484 uart_mvebu_bus_probe(struct uart_softc *sc)
485 {
486 	if (!ofw_bus_status_okay(sc->sc_dev))
487 		return (ENXIO);
488 
489 	if (!ofw_bus_search_compatible(sc->sc_dev, compat_data)->ocd_data)
490 		return (ENXIO);
491 
492 	device_set_desc(sc->sc_dev, "Marvell Armada 3700 UART");
493 
494 	sc->sc_txfifosz = 32;
495 	sc->sc_rxfifosz = 64;
496 	sc->sc_hwiflow = 0;
497 	sc->sc_hwoflow = 0;
498 
499 	return (0);
500 }
501 
502 int
503 uart_mvebu_bus_receive(struct uart_softc *sc)
504 {
505 	struct uart_bas *bas;
506 	uint32_t xc;
507 	int rx, er;
508 
509 	bas = &sc->sc_bas;
510 	uart_lock(sc->sc_hwmtx);
511 
512 	while (!(uart_getreg(bas, UART_STAT) & STAT_RX_FIFO_EMPT)) {
513 		if (uart_rx_full(sc)) {
514 			sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
515 			break;
516 		}
517 
518 		xc = uart_getreg(bas, UART_RBR);
519 		rx = xc & 0xff;
520 		er = xc & 0xf000;
521 		/*
522 		 * Formula which translates marvell error bits
523 		 * Only valid when CTRL_ST_MIRR_EN is set
524 		 */
525 		er = (er & RBR_BRK_DET) >> 7 |
526 		    (er & RBR_FRM_ERR_DET) >> 5 |
527 		    (er & RBR_PAR_ERR_DET) >> 2 |
528 		    (er & RBR_OVR_ERR_DET) >> 2;
529 
530 		uart_rx_put(sc, rx | er);
531 		uart_barrier(bas);
532 	}
533 	/*
534 	 * uart_if.m says that receive interrupt
535 	 * should be cleared, so we need to reset
536 	 * RX FIFO
537 	 */
538 
539 	if (!(uart_getreg(bas, UART_STAT) & STAT_RX_FIFO_EMPT)) {
540 		uart_mvebu_bus_flush(sc, UART_FLUSH_RECEIVER);
541 	}
542 
543 	uart_unlock(sc->sc_hwmtx);
544 	return (0);
545 }
546 
547 static int
548 uart_mvebu_bus_setsig(struct uart_softc *sc, int sig)
549 {
550 	/* Not supported by hardware */
551 	return (0);
552 }
553 
554 int
555 uart_mvebu_bus_transmit(struct uart_softc *sc)
556 {
557 	struct uart_bas *bas;
558 	int i, ctrl;
559 
560 	bas = &sc->sc_bas;
561 	uart_lock(sc->sc_hwmtx);
562 
563 	/* Turn off all interrupts during send */
564 	ctrl = uart_getreg(bas, UART_CTRL);
565 	uart_setreg(bas, UART_CTRL, ctrl & ~CTRL_INTR_MASK);
566 	uart_barrier(bas);
567 
568 	for (i = 0; i < sc->sc_txdatasz; i++) {
569 		uart_setreg(bas, UART_TSH, sc->sc_txbuf[i] & 0xff);
570 		uart_barrier(bas);
571 	}
572 
573 	/*
574 	 * Make sure that interrupt is generated
575 	 * when FIFO can get more data.
576 	 */
577 	uart_setreg(bas, UART_CTRL, ctrl | CTRL_TX_IDLE_INT);
578 	uart_barrier(bas);
579 
580 	/* Mark busy */
581 	sc->sc_txbusy = 1;
582 
583 	uart_unlock(sc->sc_hwmtx);
584 	return (0);
585 }
586 
587 static void
588 uart_mvebu_bus_grab(struct uart_softc *sc)
589 {
590 	struct uart_mvebu_softc *msc = (struct uart_mvebu_softc *)sc;
591 	struct uart_bas *bas = &sc->sc_bas;
592 	uint32_t ctrl;
593 
594 	/* Mask all interrupts */
595 	uart_lock(sc->sc_hwmtx);
596 	ctrl = uart_getreg(bas, UART_CTRL);
597 	msc->intrm = ctrl & CTRL_INTR_MASK;
598 	uart_setreg(bas, UART_CTRL, ctrl & ~CTRL_INTR_MASK);
599 	uart_barrier(bas);
600 	uart_unlock(sc->sc_hwmtx);
601 }
602 
603 static void
604 uart_mvebu_bus_ungrab(struct uart_softc *sc)
605 {
606 	struct uart_mvebu_softc *msc = (struct uart_mvebu_softc *)sc;
607 	struct uart_bas *bas = &sc->sc_bas;
608 	uint32_t ctrl;
609 
610 	/* Restore interrupts */
611 	uart_lock(sc->sc_hwmtx);
612 	ctrl = uart_getreg(bas, UART_CTRL) & ~CTRL_INTR_MASK;
613 	uart_setreg(bas, UART_CTRL, ctrl | msc->intrm);
614 	uart_barrier(bas);
615 	uart_unlock(sc->sc_hwmtx);
616 }
617 
618