uart_dev_at91usart.c revision 160357
1/*-
2 * Copyright (c) 2005 M. Warner Losh
3 * Copyright (c) 2005 Olivier Houchard
4 * All rights reserved.
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 *
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 ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD: head/sys/arm/at91/uart_dev_at91usart.c 160357 2006-07-14 21:33:04Z imp $");
30
31#include <sys/param.h>
32#include <sys/systm.h>
33#include <sys/bus.h>
34#include <sys/conf.h>
35#include <sys/cons.h>
36#include <sys/tty.h>
37#include <machine/bus.h>
38
39#include <dev/uart/uart.h>
40#include <dev/uart/uart_cpu.h>
41#include <dev/uart/uart_bus.h>
42#include <arm/at91/at91rm92reg.h>
43#include <arm/at91/at91_usartreg.h>
44#include <arm/at91/at91_pdcreg.h>
45
46#include "uart_if.h"
47
48#define DEFAULT_RCLK		AT91C_MASTER_CLOCK
49#define	USART_BUFFER_SIZE	128
50
51/*
52 * High-level UART interface.
53 */
54struct at91_usart_rx {
55	bus_addr_t	pa;
56	uint8_t		buffer[USART_BUFFER_SIZE];
57	bus_dmamap_t	map;
58};
59
60struct at91_usart_softc {
61	struct uart_softc base;
62	bus_dma_tag_t dmatag;		/* bus dma tag for mbufs */
63	bus_dmamap_t tx_map;
64	uint32_t flags;
65#define HAS_TIMEOUT	1
66	struct at91_usart_rx ping_pong[2];
67	struct at91_usart_rx *ping;
68	struct at91_usart_rx *pong;
69};
70
71#define	RD4(bas, reg)		\
72	bus_space_read_4((bas)->bst, (bas)->bsh, uart_regofs(bas, reg))
73#define	WR4(bas, reg, value)	\
74	bus_space_write_4((bas)->bst, (bas)->bsh, uart_regofs(bas, reg), value)
75
76#define	SIGCHG(c, i, s, d)				\
77	do {						\
78		if (c) {				\
79			i |= (i & s) ? s : s | d;	\
80		} else {				\
81			i = (i & s) ? (i & ~s) | d : i;	\
82		}					\
83	} while (0);
84
85#define BAUD2DIVISOR(b) \
86	((((DEFAULT_RCLK * 10) / ((b) * 16)) + 5) / 10)
87
88/*
89 * Low-level UART interface.
90 */
91static int at91_usart_probe(struct uart_bas *bas);
92static void at91_usart_init(struct uart_bas *bas, int, int, int, int);
93static void at91_usart_term(struct uart_bas *bas);
94static void at91_usart_putc(struct uart_bas *bas, int);
95static int at91_usart_poll(struct uart_bas *bas);
96static int at91_usart_getc(struct uart_bas *bas, struct mtx *mtx);
97
98extern SLIST_HEAD(uart_devinfo_list, uart_devinfo) uart_sysdevs;
99
100static int
101at91_usart_param(struct uart_bas *bas, int baudrate, int databits,
102    int stopbits, int parity)
103{
104	uint32_t mr;
105
106	/*
107	 * Assume 3-write RS-232 configuration.
108	 * XXX Not sure how uart will present the other modes to us, so
109	 * XXX they are unimplemented.  maybe ioctl?
110	 */
111	mr = USART_MR_MODE_NORMAL;
112	mr |= USART_MR_USCLKS_MCK;	/* Assume MCK */
113
114	/*
115	 * Or in the databits requested
116	 */
117	if (databits < 9)
118		mr &= ~USART_MR_MODE9;
119	switch (databits) {
120	case 5:
121		mr |= USART_MR_CHRL_5BITS;
122		break;
123	case 6:
124		mr |= USART_MR_CHRL_6BITS;
125		break;
126	case 7:
127		mr |= USART_MR_CHRL_7BITS;
128		break;
129	case 8:
130		mr |= USART_MR_CHRL_8BITS;
131		break;
132	case 9:
133		mr |= USART_MR_CHRL_8BITS | USART_MR_MODE9;
134		break;
135	default:
136		return (EINVAL);
137	}
138
139	/*
140	 * Or in the parity
141	 */
142	switch (parity) {
143	case UART_PARITY_NONE:
144		mr |= USART_MR_PAR_NONE;
145		break;
146	case UART_PARITY_ODD:
147		mr |= USART_MR_PAR_ODD;
148		break;
149	case UART_PARITY_EVEN:
150		mr |= USART_MR_PAR_EVEN;
151		break;
152	case UART_PARITY_MARK:
153		mr |= USART_MR_PAR_MARK;
154		break;
155	case UART_PARITY_SPACE:
156		mr |= USART_MR_PAR_SPACE;
157		break;
158	default:
159		return (EINVAL);
160	}
161
162	/*
163	 * Or in the stop bits.  Note: The hardware supports 1.5 stop
164	 * bits in async mode, but there's no way to specify that
165	 * AFAICT.  Instead, rely on the convention documented at
166	 * http://www.lammertbies.nl/comm/info/RS-232_specs.html which
167	 * states that 1.5 stop bits are used for 5 bit bytes and
168	 * 2 stop bits only for longer bytes.
169	 */
170	if (stopbits == 1)
171		mr |= USART_MR_NBSTOP_1;
172	else if (databits > 5)
173		mr |= USART_MR_NBSTOP_2;
174	else
175		mr |= USART_MR_NBSTOP_1_5;
176
177	/*
178	 * We want normal plumbing mode too, none of this fancy
179	 * loopback or echo mode.
180	 */
181	mr |= USART_MR_CHMODE_NORMAL;
182
183	mr &= ~USART_MR_MSBF;	/* lsb first */
184	mr &= ~USART_MR_CKLO_SCK;	/* Don't drive SCK */
185
186	WR4(bas, USART_MR, mr);
187
188	/*
189	 * Set the baud rate
190	 */
191	WR4(bas, USART_BRGR, BAUD2DIVISOR(baudrate));
192
193	/* XXX Need to take possible synchronous mode into account */
194	return (0);
195}
196
197struct uart_ops at91_usart_ops = {
198	.probe = at91_usart_probe,
199	.init = at91_usart_init,
200	.term = at91_usart_term,
201	.putc = at91_usart_putc,
202	.poll = at91_usart_poll,
203	.getc = at91_usart_getc,
204};
205
206static int
207at91_usart_probe(struct uart_bas *bas)
208{
209	/* We know that this is always here */
210	return (0);
211}
212
213/*
214 * Initialize this device for use as a console.
215 */
216static void
217at91_usart_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
218    int parity)
219{
220
221	at91_usart_param(bas, baudrate, databits, stopbits, parity);
222
223	/* Reset the rx and tx buffers and turn on rx and tx */
224	WR4(bas, USART_CR, USART_CR_RSTSTA | USART_CR_RSTRX | USART_CR_RSTTX);
225	WR4(bas, USART_CR, USART_CR_RXEN | USART_CR_TXEN);
226	WR4(bas, USART_IDR, 0xffffffff);
227}
228
229/*
230 * Free resources now that we're no longer the console.  This appears to
231 * be never called, and I'm unsure quite what to do if I am called.
232 */
233static void
234at91_usart_term(struct uart_bas *bas)
235{
236	/* XXX */
237}
238
239/*
240 * Put a character of console output (so we do it here polling rather than
241 * interrutp driven).
242 */
243static void
244at91_usart_putc(struct uart_bas *bas, int c)
245{
246
247    while (!(RD4(bas, USART_CSR) & USART_CSR_TXRDY))
248		continue;
249	WR4(bas, USART_THR, c);
250}
251
252/*
253 * Poll for a character available
254 */
255static int
256at91_usart_poll(struct uart_bas *bas)
257{
258
259	if (!(RD4(bas, USART_CSR) & USART_CSR_RXRDY))
260		return (-1);
261	return (RD4(bas, USART_RHR) & 0xff);
262}
263
264/*
265 * Block waiting for a character.
266 */
267static int
268at91_usart_getc(struct uart_bas *bas, struct mtx *mtx)
269{
270	int c;
271
272	while (!(RD4(bas, USART_CSR) & USART_CSR_RXRDY))
273		continue;
274	c = RD4(bas, USART_RHR);
275	c &= 0xff;
276	return (c);
277}
278
279static int at91_usart_bus_probe(struct uart_softc *sc);
280static int at91_usart_bus_attach(struct uart_softc *sc);
281static int at91_usart_bus_flush(struct uart_softc *, int);
282static int at91_usart_bus_getsig(struct uart_softc *);
283static int at91_usart_bus_ioctl(struct uart_softc *, int, intptr_t);
284static int at91_usart_bus_ipend(struct uart_softc *);
285static int at91_usart_bus_param(struct uart_softc *, int, int, int, int);
286static int at91_usart_bus_receive(struct uart_softc *);
287static int at91_usart_bus_setsig(struct uart_softc *, int);
288static int at91_usart_bus_transmit(struct uart_softc *);
289
290static kobj_method_t at91_usart_methods[] = {
291	KOBJMETHOD(uart_probe,		at91_usart_bus_probe),
292	KOBJMETHOD(uart_attach, 	at91_usart_bus_attach),
293	KOBJMETHOD(uart_flush,		at91_usart_bus_flush),
294	KOBJMETHOD(uart_getsig,		at91_usart_bus_getsig),
295	KOBJMETHOD(uart_ioctl,		at91_usart_bus_ioctl),
296	KOBJMETHOD(uart_ipend,		at91_usart_bus_ipend),
297	KOBJMETHOD(uart_param,		at91_usart_bus_param),
298	KOBJMETHOD(uart_receive,	at91_usart_bus_receive),
299	KOBJMETHOD(uart_setsig,		at91_usart_bus_setsig),
300	KOBJMETHOD(uart_transmit,	at91_usart_bus_transmit),
301
302	{ 0, 0 }
303};
304
305int
306at91_usart_bus_probe(struct uart_softc *sc)
307{
308	return (0);
309}
310
311#ifndef SKYEYE_WORKAROUNDS
312static void
313at91_getaddr(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
314{
315	if (error != 0)
316		return;
317	*(bus_addr_t *)arg = segs[0].ds_addr;
318}
319#endif
320
321static int
322at91_usart_bus_attach(struct uart_softc *sc)
323{
324	int err, i;
325	uint32_t cr;
326	struct at91_usart_softc *atsc;
327
328	atsc = (struct at91_usart_softc *)sc;
329
330	/*
331	 * See if we have a TIMEOUT bit.  We disable all interrupts as
332	 * a side effect.  Boot loaders may have enabled them.  Since
333	 * a TIMEOUT interrupt can't happen without other setup, the
334	 * apparent race here can't actually happen.
335	 */
336	WR4(&sc->sc_bas, USART_IDR, 0xffffffff);
337	WR4(&sc->sc_bas, USART_IER, USART_CSR_TIMEOUT);
338	if (RD4(&sc->sc_bas, USART_IMR) & USART_CSR_TIMEOUT)
339		atsc->flags |= HAS_TIMEOUT;
340	WR4(&sc->sc_bas, USART_IDR, 0xffffffff);
341
342	sc->sc_txfifosz = USART_BUFFER_SIZE;
343	sc->sc_rxfifosz = USART_BUFFER_SIZE;
344	sc->sc_hwiflow = 0;
345
346	/*
347	 * Allocate DMA tags and maps
348	 */
349	err = bus_dma_tag_create(NULL, 1, 0, BUS_SPACE_MAXADDR_32BIT,
350	    BUS_SPACE_MAXADDR, NULL, NULL, USART_BUFFER_SIZE, 1,
351	    USART_BUFFER_SIZE, BUS_DMA_ALLOCNOW, NULL, NULL, &atsc->dmatag);
352	if (err != 0)
353		goto errout;
354	err = bus_dmamap_create(atsc->dmatag, 0, &atsc->tx_map);
355	if (err != 0)
356		goto errout;
357	if (atsc->flags & HAS_TIMEOUT) {
358		for (i = 0; i < 2; i++) {
359			err = bus_dmamap_create(atsc->dmatag, 0,
360			    &atsc->ping_pong[i].map);
361			if (err != 0)
362				goto errout;
363			err = bus_dmamap_load(atsc->dmatag,
364			    atsc->ping_pong[i].map,
365			    atsc->ping_pong[i].buffer, sc->sc_rxfifosz,
366			    at91_getaddr, &atsc->ping_pong[i].pa, 0);
367			if (err != 0)
368				goto errout;
369			bus_dmamap_sync(atsc->dmatag, atsc->ping_pong[i].map,
370			    BUS_DMASYNC_PREREAD);
371		}
372		atsc->ping = &atsc->ping_pong[0];
373		atsc->pong = &atsc->ping_pong[1];
374	}
375
376	/*
377	 * Prime the pump with the RX buffer.  We use two 64 byte bounce
378	 * buffers here to avoid data overflow.
379	 */
380
381	/* Turn on rx and tx */
382	cr = USART_CR_RSTSTA | USART_CR_RSTRX | USART_CR_RSTTX;
383	WR4(&sc->sc_bas, USART_CR, cr);
384	WR4(&sc->sc_bas, USART_CR, USART_CR_RXEN | USART_CR_TXEN);
385
386	/*
387	 * Setup the PDC to receive data.  We use the ping-pong buffers
388	 * so that we can more easily bounce between the two and so that
389	 * we get an interrupt 1/2 way through the software 'fifo' we have
390	 * to avoid overruns.
391	 */
392	if (atsc->flags & HAS_TIMEOUT) {
393		WR4(&sc->sc_bas, PDC_RPR, atsc->ping->pa);
394		WR4(&sc->sc_bas, PDC_RCR, sc->sc_rxfifosz);
395		WR4(&sc->sc_bas, PDC_RNPR, atsc->pong->pa);
396		WR4(&sc->sc_bas, PDC_RNCR, sc->sc_rxfifosz);
397		WR4(&sc->sc_bas, PDC_PTCR, PDC_PTCR_RXTEN);
398
399		/* Set the receive timeout to be 1.5 character times. */
400		WR4(&sc->sc_bas, USART_RTOR, 12);
401		WR4(&sc->sc_bas, USART_CR, USART_CR_STTTO);
402		WR4(&sc->sc_bas, USART_IER, USART_CSR_TIMEOUT |
403		    USART_CSR_RXBUFF | USART_CSR_ENDRX);
404	} else {
405		WR4(&sc->sc_bas, USART_IER, USART_CSR_RXRDY);
406	}
407	WR4(&sc->sc_bas, USART_IER, USART_CSR_RXBRK);
408errout:;
409	// XXX bad
410	return (err);
411}
412
413static int
414at91_usart_bus_transmit(struct uart_softc *sc)
415{
416#ifndef SKYEYE_WORKAROUNDS
417	bus_addr_t addr;
418#endif
419	struct at91_usart_softc *atsc;
420
421	atsc = (struct at91_usart_softc *)sc;
422#ifndef SKYEYE_WORKAROUNDS
423	if (bus_dmamap_load(atsc->dmatag, atsc->tx_map, sc->sc_txbuf,
424	    sc->sc_txdatasz, at91_getaddr, &addr, 0) != 0)
425		return (EAGAIN);
426	bus_dmamap_sync(atsc->dmatag, atsc->tx_map, BUS_DMASYNC_PREWRITE);
427#endif
428
429	uart_lock(sc->sc_hwmtx);
430	sc->sc_txbusy = 1;
431#ifndef SKYEYE_WORKAROUNDS
432	/*
433	 * Setup the PDC to transfer the data and interrupt us when it
434	 * is done.  We've already requested the interrupt.
435	 */
436	WR4(&sc->sc_bas, PDC_TPR, addr);
437	WR4(&sc->sc_bas, PDC_TCR, sc->sc_txdatasz);
438	WR4(&sc->sc_bas, PDC_PTCR, PDC_PTCR_TXTEN);
439	WR4(&sc->sc_bas, USART_IER, USART_CSR_ENDTX);
440	uart_unlock(sc->sc_hwmtx);
441#else
442	for (int i = 0; i < sc->sc_txdatasz; i++)
443		at91_usart_putc(&sc->sc_bas, sc->sc_txbuf[i]);
444	/*
445	 * XXX: Gross hack : Skyeye doesn't raise an interrupt once the
446	 * transfer is done, so simulate it.
447	 */
448	WR4(&sc->sc_bas, USART_IER, USART_CSR_TXRDY);
449#endif
450	return (0);
451}
452static int
453at91_usart_bus_setsig(struct uart_softc *sc, int sig)
454{
455	uint32_t new, old, cr;
456	struct uart_bas *bas;
457
458	do {
459		old = sc->sc_hwsig;
460		new = old;
461		if (sig & SER_DDTR)
462			SIGCHG(sig & SER_DTR, new, SER_DTR, SER_DDTR);
463		if (sig & SER_DRTS)
464			SIGCHG(sig & SER_RTS, new, SER_RTS, SER_DRTS);
465	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
466	bas = &sc->sc_bas;
467	uart_lock(sc->sc_hwmtx);
468	cr = 0;
469	if (new & SER_DTR)
470		cr |= USART_CR_DTREN;
471	else
472		cr |= USART_CR_DTRDIS;
473	if (new & SER_RTS)
474		cr |= USART_CR_RTSEN;
475	else
476		cr |= USART_CR_RTSDIS;
477	WR4(bas, USART_CR, cr);
478	uart_unlock(sc->sc_hwmtx);
479	return (0);
480}
481static int
482at91_usart_bus_receive(struct uart_softc *sc)
483{
484
485	return (0);
486}
487static int
488at91_usart_bus_param(struct uart_softc *sc, int baudrate, int databits,
489    int stopbits, int parity)
490{
491
492	return (at91_usart_param(&sc->sc_bas, baudrate, databits, stopbits,
493	    parity));
494}
495static int
496at91_usart_bus_ipend(struct uart_softc *sc)
497{
498	int csr = RD4(&sc->sc_bas, USART_CSR);
499	int ipend = 0, i, len;
500	struct at91_usart_softc *atsc;
501	struct at91_usart_rx *p;
502
503	atsc = (struct at91_usart_softc *)sc;
504	if (csr & USART_CSR_ENDTX) {
505		bus_dmamap_sync(atsc->dmatag, atsc->tx_map,
506		    BUS_DMASYNC_POSTWRITE);
507		bus_dmamap_unload(atsc->dmatag, atsc->tx_map);
508	}
509	uart_lock(sc->sc_hwmtx);
510	if (csr & USART_CSR_TXRDY) {
511		if (sc->sc_txbusy)
512			ipend |= SER_INT_TXIDLE;
513		WR4(&sc->sc_bas, USART_IDR, USART_CSR_TXRDY);
514	}
515	if (csr & USART_CSR_ENDTX) {
516		if (sc->sc_txbusy)
517			ipend |= SER_INT_TXIDLE;
518		WR4(&sc->sc_bas, USART_IDR, USART_CSR_ENDTX);
519	}
520
521	/*
522	 * Due to the contraints of the DMA engine present in the
523	 * atmel chip, I can't just say I have a rx interrupt pending
524	 * and do all the work elsewhere.  I need to look at the CSR
525	 * bits right now and do things based on them to avoid races.
526	 */
527	if ((atsc->flags & HAS_TIMEOUT) && (csr & USART_CSR_RXBUFF)) {
528		// Have a buffer overflow.  Copy all data from both
529		// ping and pong.  Insert overflow character.  Reset
530		// ping and pong and re-enable the PDC to receive
531		// characters again.
532		bus_dmamap_sync(atsc->dmatag, atsc->ping->map,
533		    BUS_DMASYNC_POSTREAD);
534		bus_dmamap_sync(atsc->dmatag, atsc->pong->map,
535		    BUS_DMASYNC_POSTREAD);
536		for (i = 0; i < sc->sc_rxfifosz; i++)
537			uart_rx_put(sc, atsc->ping->buffer[i]);
538		for (i = 0; i < sc->sc_rxfifosz; i++)
539			uart_rx_put(sc, atsc->pong->buffer[i]);
540		uart_rx_put(sc, UART_STAT_OVERRUN);
541		csr &= ~(USART_CSR_ENDRX | USART_CSR_TIMEOUT);
542		WR4(&sc->sc_bas, PDC_RPR, atsc->ping->pa);
543		WR4(&sc->sc_bas, PDC_RCR, sc->sc_rxfifosz);
544		WR4(&sc->sc_bas, PDC_RNPR, atsc->pong->pa);
545		WR4(&sc->sc_bas, PDC_RNCR, sc->sc_rxfifosz);
546		WR4(&sc->sc_bas, PDC_PTCR, PDC_PTCR_RXTEN);
547		ipend |= SER_INT_RXREADY;
548	}
549	if ((atsc->flags & HAS_TIMEOUT) && (csr & USART_CSR_ENDRX)) {
550		// Shuffle data from 'ping' of ping pong buffer, but
551		// leave current 'pong' in place, as it has become the
552		// new 'ping'.  We need to copy data and setup the old
553		// 'ping' as the new 'pong' when we're done.
554		bus_dmamap_sync(atsc->dmatag, atsc->ping->map,
555		    BUS_DMASYNC_POSTREAD);
556		for (i = 0; i < sc->sc_rxfifosz; i++)
557			uart_rx_put(sc, atsc->ping->buffer[i]);
558		p = atsc->ping;
559		atsc->ping = atsc->pong;
560		atsc->pong = p;
561		WR4(&sc->sc_bas, PDC_RNPR, atsc->pong->pa);
562		WR4(&sc->sc_bas, PDC_RNCR, sc->sc_rxfifosz);
563		ipend |= SER_INT_RXREADY;
564	}
565	if ((atsc->flags & HAS_TIMEOUT) && (csr & USART_CSR_TIMEOUT)) {
566		// We have one partial buffer.  We need to stop the
567		// PDC, get the number of characters left and from
568		// that compute number of valid characters.  We then
569		// need to reset ping and pong and reenable the PDC.
570		// Not sure if there's a race here at fast baud rates
571		// we need to worry about.
572		WR4(&sc->sc_bas, PDC_PTCR, PDC_PTCR_RXTDIS);
573		bus_dmamap_sync(atsc->dmatag, atsc->ping->map,
574		    BUS_DMASYNC_POSTREAD);
575		len = sc->sc_rxfifosz - RD4(&sc->sc_bas, PDC_RCR);
576		for (i = 0; i < len; i++)
577			uart_rx_put(sc, atsc->ping->buffer[i]);
578		WR4(&sc->sc_bas, PDC_RPR, atsc->ping->pa);
579		WR4(&sc->sc_bas, PDC_RCR, sc->sc_rxfifosz);
580		WR4(&sc->sc_bas, USART_CR, USART_CR_STTTO);
581		WR4(&sc->sc_bas, PDC_PTCR, PDC_PTCR_RXTEN);
582		ipend |= SER_INT_RXREADY;
583	}
584	if (!(atsc->flags & HAS_TIMEOUT) && (csr & USART_CSR_RXRDY)) {
585		// We have another charater in a device that doesn't support
586		// timeouts, so we do it one character at a time.
587		uart_rx_put(sc, RD4(&sc->sc_bas, USART_RHR) & 0xff);
588		ipend |= SER_INT_RXREADY;
589	}
590
591	if (csr & USART_CSR_RXBRK) {
592		unsigned int cr = USART_CR_RSTSTA;
593
594		ipend |= SER_INT_BREAK;
595		WR4(&sc->sc_bas, USART_CR, cr);
596	}
597	uart_unlock(sc->sc_hwmtx);
598	return (ipend);
599}
600static int
601at91_usart_bus_flush(struct uart_softc *sc, int what)
602{
603	return (0);
604}
605
606static int
607at91_usart_bus_getsig(struct uart_softc *sc)
608{
609	uint32_t new, sig;
610	uint8_t csr;
611
612	uart_lock(sc->sc_hwmtx);
613	csr = RD4(&sc->sc_bas, USART_CSR);
614	sig = 0;
615	if (csr & USART_CSR_CTS)
616		sig |= SER_CTS;
617	if (csr & USART_CSR_DCD)
618		sig |= SER_DCD;
619	if (csr & USART_CSR_DSR)
620		sig |= SER_DSR;
621	if (csr & USART_CSR_RI)
622		sig |= SER_RI;
623	new = sig & ~SER_MASK_DELTA;
624	sc->sc_hwsig = new;
625	uart_unlock(sc->sc_hwmtx);
626	return (sig);
627}
628
629static int
630at91_usart_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
631{
632	switch (request) {
633	case UART_IOCTL_BREAK:
634	case UART_IOCTL_IFLOW:
635	case UART_IOCTL_OFLOW:
636		break;
637	case UART_IOCTL_BAUD:
638		WR4(&sc->sc_bas, USART_BRGR, BAUD2DIVISOR(*(int *)data));
639		return (0);
640	}
641	return (EINVAL);
642}
643struct uart_class at91_usart_class = {
644	"at91_usart class",
645	at91_usart_methods,
646	sizeof(struct at91_usart_softc),
647	.uc_range = 8,
648	.uc_rclk = DEFAULT_RCLK
649};
650