xref: /freebsd/sys/dev/uart/uart_dev_quicc.c (revision c6ec7d31830ab1c80edae95ad5e4b9dba10c47ac)
1 /*-
2  * Copyright (c) 2006 Juniper Networks
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  *
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/conf.h>
34 #include <sys/endian.h>
35 #include <machine/bus.h>
36 
37 #include <dev/ic/quicc.h>
38 
39 #include <dev/uart/uart.h>
40 #include <dev/uart/uart_cpu.h>
41 #include <dev/uart/uart_bus.h>
42 
43 #include "uart_if.h"
44 
45 #define	DEFAULT_RCLK	((266000000 * 2) / 16)
46 
47 #define	quicc_read2(bas, reg)		\
48 	bus_space_read_2((bas)->bst, (bas)->bsh, reg)
49 #define	quicc_read4(bas, reg)		\
50 	bus_space_read_4((bas)->bst, (bas)->bsh, reg)
51 
52 #define	quicc_write2(bas, reg, val)	\
53 	bus_space_write_2((bas)->bst, (bas)->bsh, reg, val)
54 #define	quicc_write4(bas, reg, val)	\
55 	bus_space_write_4((bas)->bst, (bas)->bsh, reg, val)
56 
57 static int
58 quicc_divisor(int rclk, int baudrate)
59 {
60 	int act_baud, divisor, error;
61 
62 	if (baudrate == 0)
63 		return (-1);
64 
65 	divisor = rclk / baudrate / 16;
66 	if (divisor > 4096)
67 		divisor = ((divisor >> 3) - 2) | 1;
68 	else if (divisor >= 0)
69 		divisor = (divisor - 1) << 1;
70 	if (divisor < 0 || divisor >= 8192)
71 		return (-1);
72 	act_baud = rclk / (((divisor >> 1) + 1) << ((divisor & 1) ? 8 : 4));
73 
74 	/* 10 times error in percent: */
75 	error = ((act_baud - baudrate) * 2000 / baudrate + 1) >> 1;
76 
77 	/* 3.0% maximum error tolerance: */
78 	if (error < -30 || error > 30)
79 		return (-1);
80 
81 	return (divisor);
82 }
83 
84 static int
85 quicc_param(struct uart_bas *bas, int baudrate, int databits, int stopbits,
86     int parity)
87 {
88 	int divisor;
89 	uint16_t psmr;
90 
91 	if (baudrate > 0) {
92 		divisor = quicc_divisor(bas->rclk, baudrate);
93 		if (divisor == -1)
94 			return (EINVAL);
95 		quicc_write4(bas, QUICC_REG_BRG(bas->chan - 1),
96 		    divisor | 0x10000);
97 	}
98 
99 	psmr = 0;
100 	switch (databits) {
101 	case 5:		psmr |= 0x0000; break;
102 	case 6:		psmr |= 0x1000; break;
103 	case 7:		psmr |= 0x2000; break;
104 	case 8:		psmr |= 0x3000; break;
105 	default:	return (EINVAL);
106 	}
107 	switch (stopbits) {
108 	case 1:		psmr |= 0x0000; break;
109 	case 2:		psmr |= 0x4000; break;
110 	default:	return (EINVAL);
111 	}
112 	switch (parity) {
113 	case UART_PARITY_EVEN:	psmr |= 0x1a; break;
114 	case UART_PARITY_MARK:	psmr |= 0x1f; break;
115 	case UART_PARITY_NONE:	psmr |= 0x00; break;
116 	case UART_PARITY_ODD:	psmr |= 0x10; break;
117 	case UART_PARITY_SPACE:	psmr |= 0x15; break;
118 	default:		return (EINVAL);
119 	}
120 	quicc_write2(bas, QUICC_REG_SCC_PSMR(bas->chan - 1), psmr);
121 	return (0);
122 }
123 
124 static void
125 quicc_setup(struct uart_bas *bas, int baudrate, int databits, int stopbits,
126     int parity)
127 {
128 
129 	if (bas->rclk == 0)
130 		bas->rclk = DEFAULT_RCLK;
131 
132 	/*
133 	 * GSMR_L = 0x00028034
134 	 * GSMR_H = 0x00000020
135 	 */
136 	quicc_param(bas, baudrate, databits, stopbits, parity);
137 
138 	quicc_write2(bas, QUICC_REG_SCC_SCCE(bas->chan - 1), ~0);
139 	quicc_write2(bas, QUICC_REG_SCC_SCCM(bas->chan - 1), 0x0027);
140 }
141 
142 /*
143  * Low-level UART interface.
144  */
145 static int quicc_probe(struct uart_bas *bas);
146 static void quicc_init(struct uart_bas *bas, int, int, int, int);
147 static void quicc_term(struct uart_bas *bas);
148 static void quicc_putc(struct uart_bas *bas, int);
149 static int quicc_rxready(struct uart_bas *bas);
150 static int quicc_getc(struct uart_bas *bas, struct mtx *);
151 
152 static struct uart_ops uart_quicc_ops = {
153 	.probe = quicc_probe,
154 	.init = quicc_init,
155 	.term = quicc_term,
156 	.putc = quicc_putc,
157 	.rxready = quicc_rxready,
158 	.getc = quicc_getc,
159 };
160 
161 static int
162 quicc_probe(struct uart_bas *bas)
163 {
164 
165 	return (0);
166 }
167 
168 static void
169 quicc_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
170     int parity)
171 {
172 
173 	quicc_setup(bas, baudrate, databits, stopbits, parity);
174 }
175 
176 static void
177 quicc_term(struct uart_bas *bas)
178 {
179 }
180 
181 static void
182 quicc_putc(struct uart_bas *bas, int c)
183 {
184 	int unit;
185 	uint16_t toseq;
186 
187 	unit = bas->chan - 1;
188 	while (quicc_read2(bas, QUICC_PRAM_SCC_UART_TOSEQ(unit)) & 0x2000)
189 		DELAY(10);
190 
191 	toseq = 0x2000 | (c & 0xff);
192 	quicc_write2(bas, QUICC_PRAM_SCC_UART_TOSEQ(unit), toseq);
193 }
194 
195 static int
196 quicc_rxready(struct uart_bas *bas)
197 {
198 	uint16_t rb;
199 
200 	rb = quicc_read2(bas, QUICC_PRAM_SCC_RBASE(bas->chan - 1));
201 	return ((quicc_read2(bas, rb) & 0x8000) ? 0 : 1);
202 }
203 
204 static int
205 quicc_getc(struct uart_bas *bas, struct mtx *hwmtx)
206 {
207 	volatile char *buf;
208 	int c;
209 	uint16_t rb, sc;
210 
211 	uart_lock(hwmtx);
212 
213 	rb = quicc_read2(bas, QUICC_PRAM_SCC_RBASE(bas->chan - 1));
214 
215 	while ((sc = quicc_read2(bas, rb)) & 0x8000) {
216 		uart_unlock(hwmtx);
217 		DELAY(4);
218 		uart_lock(hwmtx);
219 	}
220 
221 	buf = (void *)(uintptr_t)quicc_read4(bas, rb + 4);
222 	c = *buf;
223 	quicc_write2(bas, rb, sc | 0x8000);
224 
225 	uart_unlock(hwmtx);
226 
227 	return (c);
228 }
229 
230 /*
231  * High-level UART interface.
232  */
233 struct quicc_softc {
234 	struct uart_softc base;
235 };
236 
237 static int quicc_bus_attach(struct uart_softc *);
238 static int quicc_bus_detach(struct uart_softc *);
239 static int quicc_bus_flush(struct uart_softc *, int);
240 static int quicc_bus_getsig(struct uart_softc *);
241 static int quicc_bus_ioctl(struct uart_softc *, int, intptr_t);
242 static int quicc_bus_ipend(struct uart_softc *);
243 static int quicc_bus_param(struct uart_softc *, int, int, int, int);
244 static int quicc_bus_probe(struct uart_softc *);
245 static int quicc_bus_receive(struct uart_softc *);
246 static int quicc_bus_setsig(struct uart_softc *, int);
247 static int quicc_bus_transmit(struct uart_softc *);
248 
249 static kobj_method_t quicc_methods[] = {
250 	KOBJMETHOD(uart_attach,		quicc_bus_attach),
251 	KOBJMETHOD(uart_detach,		quicc_bus_detach),
252 	KOBJMETHOD(uart_flush,		quicc_bus_flush),
253 	KOBJMETHOD(uart_getsig,		quicc_bus_getsig),
254 	KOBJMETHOD(uart_ioctl,		quicc_bus_ioctl),
255 	KOBJMETHOD(uart_ipend,		quicc_bus_ipend),
256 	KOBJMETHOD(uart_param,		quicc_bus_param),
257 	KOBJMETHOD(uart_probe,		quicc_bus_probe),
258 	KOBJMETHOD(uart_receive,	quicc_bus_receive),
259 	KOBJMETHOD(uart_setsig,		quicc_bus_setsig),
260 	KOBJMETHOD(uart_transmit,	quicc_bus_transmit),
261 	{ 0, 0 }
262 };
263 
264 struct uart_class uart_quicc_class = {
265 	"quicc",
266 	quicc_methods,
267 	sizeof(struct quicc_softc),
268 	.uc_ops = &uart_quicc_ops,
269 	.uc_range = 2,
270 	.uc_rclk = DEFAULT_RCLK
271 };
272 
273 #define	SIGCHG(c, i, s, d)				\
274 	if (c) {					\
275 		i |= (i & s) ? s : s | d;		\
276 	} else {					\
277 		i = (i & s) ? (i & ~s) | d : i;		\
278 	}
279 
280 static int
281 quicc_bus_attach(struct uart_softc *sc)
282 {
283 	struct uart_bas *bas;
284 	struct uart_devinfo *di;
285 	uint16_t st, rb;
286 
287 	bas = &sc->sc_bas;
288 	if (sc->sc_sysdev != NULL) {
289 		di = sc->sc_sysdev;
290 		quicc_param(bas, di->baudrate, di->databits, di->stopbits,
291 		    di->parity);
292 	} else {
293 		quicc_setup(bas, 9600, 8, 1, UART_PARITY_NONE);
294 	}
295 
296 	sc->sc_rxfifosz = 1;
297 	sc->sc_txfifosz = 1;
298 
299 	/* Enable interrupts on the receive buffer. */
300 	rb = quicc_read2(bas, QUICC_PRAM_SCC_RBASE(bas->chan - 1));
301 	st = quicc_read2(bas, rb);
302 	quicc_write2(bas, rb, st | 0x9000);
303 
304 	(void)quicc_bus_getsig(sc);
305 
306 	return (0);
307 }
308 
309 static int
310 quicc_bus_detach(struct uart_softc *sc)
311 {
312 
313 	return (0);
314 }
315 
316 static int
317 quicc_bus_flush(struct uart_softc *sc, int what)
318 {
319 
320 	return (0);
321 }
322 
323 static int
324 quicc_bus_getsig(struct uart_softc *sc)
325 {
326 	uint32_t new, old, sig;
327 	uint32_t dummy;
328 
329 	do {
330 		old = sc->sc_hwsig;
331 		sig = old;
332 		uart_lock(sc->sc_hwmtx);
333 		/* XXX SIGNALS */
334 		dummy = 0;
335 		uart_unlock(sc->sc_hwmtx);
336 		SIGCHG(dummy, sig, SER_CTS, SER_DCTS);
337 		SIGCHG(dummy, sig, SER_DCD, SER_DDCD);
338 		SIGCHG(dummy, sig, SER_DSR, SER_DDSR);
339 		new = sig & ~SER_MASK_DELTA;
340 	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
341 	return (sig);
342 }
343 
344 static int
345 quicc_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
346 {
347 	struct uart_bas *bas;
348 	uint32_t brg;
349 	int baudrate, error;
350 
351 	bas = &sc->sc_bas;
352 	error = 0;
353 	uart_lock(sc->sc_hwmtx);
354 	switch (request) {
355 	case UART_IOCTL_BREAK:
356 		break;
357 	case UART_IOCTL_BAUD:
358 		brg = quicc_read4(bas, QUICC_REG_BRG(bas->chan - 1)) & 0x1fff;
359 		brg = (brg & 1) ? (brg + 1) << 3 : (brg + 2) >> 1;
360 		baudrate = bas->rclk / (brg * 16);
361 		*(int*)data = baudrate;
362 		break;
363 	default:
364 		error = EINVAL;
365 		break;
366 	}
367 	uart_unlock(sc->sc_hwmtx);
368 	return (error);
369 }
370 
371 static int
372 quicc_bus_ipend(struct uart_softc *sc)
373 {
374 	struct uart_bas *bas;
375 	int ipend;
376 	uint16_t scce;
377 
378 	bas = &sc->sc_bas;
379 	ipend = 0;
380 
381 	uart_lock(sc->sc_hwmtx);
382 	scce = quicc_read2(bas, QUICC_REG_SCC_SCCE(bas->chan - 1));
383 	quicc_write2(bas, QUICC_REG_SCC_SCCE(bas->chan - 1), ~0);
384 	uart_unlock(sc->sc_hwmtx);
385 	if (scce & 0x0001)
386 		ipend |= SER_INT_RXREADY;
387 	if (scce & 0x0002)
388 		ipend |= SER_INT_TXIDLE;
389 	if (scce & 0x0004)
390 		ipend |= SER_INT_OVERRUN;
391 	if (scce & 0x0020)
392 		ipend |= SER_INT_BREAK;
393 	/* XXX SIGNALS */
394 	return (ipend);
395 }
396 
397 static int
398 quicc_bus_param(struct uart_softc *sc, int baudrate, int databits,
399     int stopbits, int parity)
400 {
401 	int error;
402 
403 	uart_lock(sc->sc_hwmtx);
404 	error = quicc_param(&sc->sc_bas, baudrate, databits, stopbits,
405 	    parity);
406 	uart_unlock(sc->sc_hwmtx);
407 	return (error);
408 }
409 
410 static int
411 quicc_bus_probe(struct uart_softc *sc)
412 {
413 	char buf[80];
414 	int error;
415 
416 	error = quicc_probe(&sc->sc_bas);
417 	if (error)
418 		return (error);
419 
420 	snprintf(buf, sizeof(buf), "quicc, channel %d", sc->sc_bas.chan);
421 	device_set_desc_copy(sc->sc_dev, buf);
422 	return (0);
423 }
424 
425 static int
426 quicc_bus_receive(struct uart_softc *sc)
427 {
428 	struct uart_bas *bas;
429 	volatile char *buf;
430 	uint16_t st, rb;
431 
432 	bas = &sc->sc_bas;
433 	uart_lock(sc->sc_hwmtx);
434 	rb = quicc_read2(bas, QUICC_PRAM_SCC_RBASE(bas->chan - 1));
435 	st = quicc_read2(bas, rb);
436 	buf = (void *)(uintptr_t)quicc_read4(bas, rb + 4);
437 	uart_rx_put(sc, *buf);
438 	quicc_write2(bas, rb, st | 0x9000);
439 	uart_unlock(sc->sc_hwmtx);
440 	return (0);
441 }
442 
443 static int
444 quicc_bus_setsig(struct uart_softc *sc, int sig)
445 {
446 	struct uart_bas *bas;
447 	uint32_t new, old;
448 
449 	bas = &sc->sc_bas;
450 	do {
451 		old = sc->sc_hwsig;
452 		new = old;
453 		if (sig & SER_DDTR) {
454 			SIGCHG(sig & SER_DTR, new, SER_DTR,
455 			    SER_DDTR);
456 		}
457 		if (sig & SER_DRTS) {
458 			SIGCHG(sig & SER_RTS, new, SER_RTS,
459 			    SER_DRTS);
460 		}
461 	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
462 
463 	uart_lock(sc->sc_hwmtx);
464 	/* XXX SIGNALS */
465 	uart_unlock(sc->sc_hwmtx);
466 	return (0);
467 }
468 
469 static int
470 quicc_bus_transmit(struct uart_softc *sc)
471 {
472 	volatile char *buf;
473 	struct uart_bas *bas;
474 	uint16_t st, tb;
475 
476 	bas = &sc->sc_bas;
477 	uart_lock(sc->sc_hwmtx);
478 	tb = quicc_read2(bas, QUICC_PRAM_SCC_TBASE(bas->chan - 1));
479 	st = quicc_read2(bas, tb);
480 	buf = (void *)(uintptr_t)quicc_read4(bas, tb + 4);
481 	*buf = sc->sc_txbuf[0];
482 	quicc_write2(bas, tb + 2, 1);
483 	quicc_write2(bas, tb, st | 0x9000);
484 	sc->sc_txbusy = 1;
485 	uart_unlock(sc->sc_hwmtx);
486 	return (0);
487 }
488