uart_dev_at91usart.c revision 157570
1/*-
2 * Copyright (c) 2005 M. Warner Losh
3 * Copyright (c) 2005 cognet
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 157570 2006-04-06 20:47:54Z cognet $");
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/*
49 * High-level UART interface.
50 */
51struct at91_usart_softc {
52	struct uart_softc base;
53	bus_dma_tag_t dmatag;		/* bus dma tag for mbufs */
54	bus_dmamap_t tx_map;
55	bus_dmamap_t rx_map;
56};
57
58#define DEFAULT_RCLK		AT91C_MASTER_CLOCK
59#define	USART_BUFFER_SIZE	128
60
61#define	RD4(bas, reg)		\
62	bus_space_read_4((bas)->bst, (bas)->bsh, uart_regofs(bas, reg))
63#define	WR4(bas, reg, value)	\
64	bus_space_write_4((bas)->bst, (bas)->bsh, uart_regofs(bas, reg), value)
65
66#define	SIGCHG(c, i, s, d)				\
67	do {						\
68		if (c) {				\
69			i |= (i & s) ? s : s | d;	\
70		} else {				\
71			i = (i & s) ? (i & ~s) | d : i;	\
72		}					\
73	} while (0);
74
75/*
76 * Low-level UART interface.
77 */
78static int at91_usart_probe(struct uart_bas *bas);
79static void at91_usart_init(struct uart_bas *bas, int, int, int, int);
80static void at91_usart_term(struct uart_bas *bas);
81static void at91_usart_putc(struct uart_bas *bas, int);
82static int at91_usart_poll(struct uart_bas *bas);
83static int at91_usart_getc(struct uart_bas *bas, struct mtx *mtx);
84
85extern SLIST_HEAD(uart_devinfo_list, uart_devinfo) uart_sysdevs;
86
87static int
88at91_usart_param(struct uart_bas *bas, int baudrate, int databits,
89    int stopbits, int parity)
90{
91	uint32_t mr;
92
93	/*
94	 * Assume 3-write RS-232 configuration.
95	 * XXX Not sure how uart will present the other modes to us, so
96	 * XXX they are unimplemented.  maybe ioctl?
97	 */
98	mr = USART_MR_MODE_NORMAL;
99	mr |= USART_MR_USCLKS_MCK;	/* Assume MCK */
100
101	/*
102	 * Or in the databits requested
103	 */
104	if (databits < 9)
105		mr &= ~USART_MR_MODE9;
106	switch (databits) {
107	case 5:
108		mr |= USART_MR_CHRL_5BITS;
109		break;
110	case 6:
111		mr |= USART_MR_CHRL_6BITS;
112		break;
113	case 7:
114		mr |= USART_MR_CHRL_7BITS;
115		break;
116	case 8:
117		mr |= USART_MR_CHRL_8BITS;
118		break;
119	case 9:
120		mr |= USART_MR_CHRL_8BITS | USART_MR_MODE9;
121		break;
122	default:
123		return (EINVAL);
124	}
125
126	/*
127	 * Or in the parity
128	 */
129	switch (parity) {
130	case UART_PARITY_NONE:
131		mr |= USART_MR_PAR_NONE;
132		break;
133	case UART_PARITY_ODD:
134		mr |= USART_MR_PAR_ODD;
135		break;
136	case UART_PARITY_EVEN:
137		mr |= USART_MR_PAR_EVEN;
138		break;
139	case UART_PARITY_MARK:
140		mr |= USART_MR_PAR_MARK;
141		break;
142	case UART_PARITY_SPACE:
143		mr |= USART_MR_PAR_SPACE;
144		break;
145	default:
146		return (EINVAL);
147	}
148
149	/*
150	 * Or in the stop bits.  Note: The hardware supports
151	 * 1.5 stop bits in async mode, but there's no way to
152	 * specify that AFAICT.
153	 */
154	if (stopbits > 1)
155		mr |= USART_MR_NBSTOP_2;
156	else
157		mr |= USART_MR_NBSTOP_2;
158	/* else if (stopbits == 1.5)
159		mr |= USART_MR_NBSTOP_1_5; */
160
161	/*
162	 * We want normal plumbing mode too, none of this fancy
163	 * loopback or echo mode.
164	 */
165	mr |= USART_MR_CHMODE_NORMAL;
166
167	mr &= ~USART_MR_MSBF;	/* lsb first */
168	mr &= ~USART_MR_CKLO_SCK;	/* Don't drive SCK */
169
170	/* XXX Need to take possible synchronous mode into account */
171	return (0);
172}
173
174struct uart_ops at91_usart_ops = {
175	.probe = at91_usart_probe,
176	.init = at91_usart_init,
177	.term = at91_usart_term,
178	.putc = at91_usart_putc,
179	.poll = at91_usart_poll,
180	.getc = at91_usart_getc,
181};
182
183static int
184at91_usart_probe(struct uart_bas *bas)
185{
186	/* We know that this is always here */
187	return (0);
188}
189
190/*
191 * Initialize this device (I think as the console)
192 */
193static void
194at91_usart_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
195    int parity)
196{
197	int cr;
198
199	at91_usart_param(bas, baudrate, databits, stopbits, parity);
200
201	/* Turn on rx and tx */
202	cr = USART_CR_RSTSTA | USART_CR_RSTRX | USART_CR_RSTTX;
203	WR4(bas, USART_CR, cr);
204	WR4(bas, USART_CR, USART_CR_RXEN | USART_CR_TXEN);
205	WR4(bas, USART_IER, USART_CSR_TIMEOUT |
206	    USART_CSR_TXRDY | USART_CSR_RXRDY |
207	    USART_CSR_RXBRK | USART_CSR_ENDRX | USART_CSR_ENDTX);
208	/* Set the receive timeout to be 1.5 character times. */
209	WR4(bas, USART_RTOR, 12);
210}
211
212/*
213 * Free resources now that we're no longer the console.  This appears to
214 * be never called, and I'm unsure quite what to do if I am called.
215 */
216static void
217at91_usart_term(struct uart_bas *bas)
218{
219	/* XXX */
220}
221
222/*
223 * Put a character of console output (so we do it here polling rather than
224 * interrutp driven).
225 */
226static void
227at91_usart_putc(struct uart_bas *bas, int c)
228{
229
230	while (!(RD4(bas, USART_CSR) &
231	    USART_CSR_TXRDY));
232	WR4(bas, USART_THR, c);
233}
234
235/*
236 * Poll for a character available
237 */
238static int
239at91_usart_poll(struct uart_bas *bas)
240{
241
242	if (!(RD4(bas, USART_CSR) & USART_CSR_RXRDY))
243		return (-1);
244	return (RD4(bas, USART_RHR) & 0xff);
245}
246
247/*
248 * Block waiting for a character.
249 */
250static int
251at91_usart_getc(struct uart_bas *bas, struct mtx *mtx)
252{
253	int c;
254
255	while (!(RD4(bas, USART_CSR) & USART_CSR_RXRDY))
256		;
257	c = RD4(bas, USART_RHR);
258	c &= 0xff;
259	return (c);
260}
261
262static int at91_usart_bus_probe(struct uart_softc *sc);
263static int at91_usart_bus_attach(struct uart_softc *sc);
264static int at91_usart_bus_flush(struct uart_softc *, int);
265static int at91_usart_bus_getsig(struct uart_softc *);
266static int at91_usart_bus_ioctl(struct uart_softc *, int, intptr_t);
267static int at91_usart_bus_ipend(struct uart_softc *);
268static int at91_usart_bus_param(struct uart_softc *, int, int, int, int);
269static int at91_usart_bus_receive(struct uart_softc *);
270static int at91_usart_bus_setsig(struct uart_softc *, int);
271static int at91_usart_bus_transmit(struct uart_softc *);
272
273static kobj_method_t at91_usart_methods[] = {
274	KOBJMETHOD(uart_probe,		at91_usart_bus_probe),
275	KOBJMETHOD(uart_attach, 	at91_usart_bus_attach),
276	KOBJMETHOD(uart_flush,		at91_usart_bus_flush),
277	KOBJMETHOD(uart_getsig,		at91_usart_bus_getsig),
278	KOBJMETHOD(uart_ioctl,		at91_usart_bus_ioctl),
279	KOBJMETHOD(uart_ipend,		at91_usart_bus_ipend),
280	KOBJMETHOD(uart_param,		at91_usart_bus_param),
281	KOBJMETHOD(uart_receive,	at91_usart_bus_receive),
282	KOBJMETHOD(uart_setsig,		at91_usart_bus_setsig),
283	KOBJMETHOD(uart_transmit,	at91_usart_bus_transmit),
284
285	{ 0, 0 }
286};
287
288int
289at91_usart_bus_probe(struct uart_softc *sc)
290{
291	return (0);
292}
293
294static int
295at91_usart_bus_attach(struct uart_softc *sc)
296{
297	int err;
298	struct at91_usart_softc *atsc;
299
300	atsc = (struct at91_usart_softc *)sc;
301
302	sc->sc_txfifosz = USART_BUFFER_SIZE;
303	sc->sc_rxfifosz = USART_BUFFER_SIZE;
304	sc->sc_hwiflow = 0;
305
306	/*
307	 * Allocate DMA tags and maps
308	 */
309	err = bus_dma_tag_create(NULL, 1, 0, BUS_SPACE_MAXADDR_32BIT,
310	    BUS_SPACE_MAXADDR, NULL, NULL, USART_BUFFER_SIZE, 1,
311	    USART_BUFFER_SIZE, BUS_DMA_ALLOCNOW, NULL, NULL, &atsc->dmatag);
312	if (err != 0)
313		goto errout;
314	err = bus_dmamap_create(atsc->dmatag, 0, &atsc->tx_map);
315	if (err != 0)
316	    goto errout;
317	err = bus_dmamap_create(atsc->dmatag, 0, &atsc->rx_map);
318	if (err != 0)
319	    goto errout;
320errout:;
321	// XXX bad
322	return (err);
323}
324
325static void
326at91_getaddr(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
327{
328	if (error != 0)
329		return;
330	*(bus_addr_t *)arg = segs[0].ds_addr;
331}
332
333
334static int
335at91_usart_bus_transmit(struct uart_softc *sc)
336{
337	bus_addr_t addr;
338	struct at91_usart_softc *atsc;
339
340	atsc = (struct at91_usart_softc *)sc;
341	if (bus_dmamap_load(atsc->dmatag, atsc->tx_map, sc->sc_txbuf,
342	    sc->sc_txdatasz, at91_getaddr, &addr, 0) != 0)
343		return (EAGAIN);
344	bus_dmamap_sync(atsc->dmatag, atsc->tx_map, BUS_DMASYNC_PREWRITE);
345
346	uart_lock(sc->sc_hwmtx);
347	sc->sc_txbusy = 1;
348	/*
349	 * Setup the PDC to transfer the data and interrupt us when it
350	 * is done.  We've already requested the interrupt.
351	 */
352	WR4(&sc->sc_bas, PDC_TPR, addr);
353	WR4(&sc->sc_bas, PDC_TCR, sc->sc_txdatasz);
354	WR4(&sc->sc_bas, PDC_PTCR, PDC_PTCR_TXTEN);
355	uart_unlock(sc->sc_hwmtx);
356#ifdef USART0_CONSOLE
357	/*
358	 * XXX: Gross hack : Skyeye doesn't raise an interrupt once the
359	 * transfer is done, so simulate it.
360	 */
361	WR4(&sc->sc_bas, USART_IER, USART_CSR_TXRDY);
362#endif
363	return (0);
364}
365static int
366at91_usart_bus_setsig(struct uart_softc *sc, int sig)
367{
368	uint32_t new, old, cr;
369	struct uart_bas *bas;
370
371	do {
372		old = sc->sc_hwsig;
373		new = old;
374		if (sig & SER_DDTR)
375			SIGCHG(sig & SER_DTR, new, SER_DTR, SER_DDTR);
376		if (sig & SER_DRTS)
377			SIGCHG(sig & SER_RTS, new, SER_RTS, SER_DRTS);
378	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
379	bas = &sc->sc_bas;
380	uart_lock(sc->sc_hwmtx);
381	cr = RD4(bas, USART_CR);
382	cr &= ~(USART_CR_DTREN | USART_CR_DTRDIS | USART_CR_RTSEN |
383	    USART_CR_RTSDIS);
384	if (new & SER_DTR)
385		cr |= USART_CR_DTREN;
386	else
387		cr |= USART_CR_DTRDIS;
388	if (new & SER_RTS)
389		cr |= USART_CR_RTSEN;
390	else
391		cr |= USART_CR_RTSDIS;
392	WR4(bas, USART_CR, cr);
393	uart_unlock(sc->sc_hwmtx);
394	return (0);
395}
396static int
397at91_usart_bus_receive(struct uart_softc *sc)
398{
399
400	uart_lock(sc->sc_hwmtx);
401	uart_rx_put(sc, at91_usart_getc(&sc->sc_bas, NULL));
402	uart_unlock(sc->sc_hwmtx);
403	return (0);
404}
405static int
406at91_usart_bus_param(struct uart_softc *sc, int baudrate, int databits,
407    int stopbits, int parity)
408{
409	return (at91_usart_param(&sc->sc_bas, baudrate, databits, stopbits,
410	    parity));
411}
412static int
413at91_usart_bus_ipend(struct uart_softc *sc)
414{
415	int csr = RD4(&sc->sc_bas, USART_CSR);
416	int ipend = 0;
417	struct at91_usart_softc *atsc;
418
419	atsc = (struct at91_usart_softc *)sc;
420#ifdef USART0_CONSOLE
421	/*
422	 * XXX: We have to cheat for skyeye, as it will return 0xff for all
423	 * the devices it doesn't emulate.
424	 */
425	if (sc->sc_bas.chan != 1)
426		return (0);
427#endif
428
429	if (csr & USART_CSR_ENDTX) {
430		bus_dmamap_sync(atsc->dmatag, atsc->tx_map,
431		    BUS_DMASYNC_POSTWRITE);
432		bus_dmamap_unload(atsc->dmatag, atsc->tx_map);
433	}
434	uart_lock(sc->sc_hwmtx);
435	if (csr & USART_CSR_TXRDY && sc->sc_txbusy)
436		ipend |= SER_INT_TXIDLE;
437	if (csr & USART_CSR_ENDTX && sc->sc_txbusy)
438		ipend |= SER_INT_TXIDLE;
439	if (csr & (USART_CSR_RXRDY /* | USART_CSR_ENDRX | USART_CSR_TIMEOUT */))
440		ipend |= SER_INT_RXREADY;
441	if (csr & USART_CSR_RXBRK) {
442		unsigned int cr = USART_CR_RSTSTA;
443
444		ipend |= SER_INT_BREAK;
445		WR4(&sc->sc_bas, USART_CR, cr);
446	}
447	uart_unlock(sc->sc_hwmtx);
448	return (ipend);
449}
450static int
451at91_usart_bus_flush(struct uart_softc *sc, int what)
452{
453	return (0);
454}
455
456static int
457at91_usart_bus_getsig(struct uart_softc *sc)
458{
459	uint32_t new, sig;
460	uint8_t csr;
461
462	uart_lock(sc->sc_hwmtx);
463	csr = RD4(&sc->sc_bas, USART_CSR);
464	sig = 0;
465	if (csr & USART_CSR_CTS)
466		sig |= SER_CTS;
467	if (csr & USART_CSR_DCD)
468		sig |= SER_DCD;
469	if (csr & USART_CSR_DSR)
470		sig |= SER_DSR;
471	if (csr & USART_CSR_RI)
472		sig |= SER_RI;
473	new = sig & ~SER_MASK_DELTA;
474	sc->sc_hwsig = new;
475	uart_unlock(sc->sc_hwmtx);
476	return (sig);
477}
478
479static int
480at91_usart_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
481{
482	return (EINVAL);
483}
484struct uart_class at91_usart_class = {
485	"at91_usart class",
486	at91_usart_methods,
487	sizeof(struct at91_usart_softc),
488	.uc_range = 8,
489	.uc_rclk = DEFAULT_RCLK
490};
491