xref: /freebsd/sys/dev/uart/uart_dev_quicc.c (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2006 Juniper Networks
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/bus.h>
32 #include <sys/conf.h>
33 #include <sys/endian.h>
34 #include <machine/bus.h>
35 
36 #include <dev/ic/quicc.h>
37 
38 #include <dev/uart/uart.h>
39 #include <dev/uart/uart_cpu.h>
40 #include <dev/uart/uart_bus.h>
41 
42 #include "uart_if.h"
43 
44 #define	DEFAULT_RCLK	((266000000 * 2) / 16)
45 
46 #define	quicc_read2(bas, reg)		\
47 	bus_space_read_2((bas)->bst, (bas)->bsh, reg)
48 #define	quicc_read4(bas, reg)		\
49 	bus_space_read_4((bas)->bst, (bas)->bsh, reg)
50 
51 #define	quicc_write2(bas, reg, val)	\
52 	bus_space_write_2((bas)->bst, (bas)->bsh, reg, val)
53 #define	quicc_write4(bas, reg, val)	\
54 	bus_space_write_4((bas)->bst, (bas)->bsh, reg, val)
55 
56 static int
57 quicc_divisor(int rclk, int baudrate)
58 {
59 	int act_baud, divisor, error;
60 
61 	if (baudrate == 0)
62 		return (-1);
63 
64 	divisor = rclk / baudrate / 16;
65 	if (divisor > 4096)
66 		divisor = ((divisor >> 3) - 2) | 1;
67 	else if (divisor >= 0)
68 		divisor = (divisor - 1) << 1;
69 	if (divisor < 0 || divisor >= 8192)
70 		return (-1);
71 	act_baud = rclk / (((divisor >> 1) + 1) << ((divisor & 1) ? 8 : 4));
72 
73 	/* 10 times error in percent: */
74 	error = ((act_baud - baudrate) * 2000 / baudrate + 1) >> 1;
75 
76 	/* 3.0% maximum error tolerance: */
77 	if (error < -30 || error > 30)
78 		return (-1);
79 
80 	return (divisor);
81 }
82 
83 static int
84 quicc_param(struct uart_bas *bas, int baudrate, int databits, int stopbits,
85     int parity)
86 {
87 	int divisor;
88 	uint16_t psmr;
89 
90 	if (baudrate > 0) {
91 		divisor = quicc_divisor(bas->rclk, baudrate);
92 		if (divisor == -1)
93 			return (EINVAL);
94 		quicc_write4(bas, QUICC_REG_BRG(bas->chan - 1),
95 		    divisor | 0x10000);
96 	}
97 
98 	psmr = 0;
99 	switch (databits) {
100 	case 5:		psmr |= 0x0000; break;
101 	case 6:		psmr |= 0x1000; break;
102 	case 7:		psmr |= 0x2000; break;
103 	case 8:		psmr |= 0x3000; break;
104 	default:	return (EINVAL);
105 	}
106 	switch (stopbits) {
107 	case 1:		psmr |= 0x0000; break;
108 	case 2:		psmr |= 0x4000; break;
109 	default:	return (EINVAL);
110 	}
111 	switch (parity) {
112 	case UART_PARITY_EVEN:	psmr |= 0x1a; break;
113 	case UART_PARITY_MARK:	psmr |= 0x1f; break;
114 	case UART_PARITY_NONE:	psmr |= 0x00; break;
115 	case UART_PARITY_ODD:	psmr |= 0x10; break;
116 	case UART_PARITY_SPACE:	psmr |= 0x15; break;
117 	default:		return (EINVAL);
118 	}
119 	quicc_write2(bas, QUICC_REG_SCC_PSMR(bas->chan - 1), psmr);
120 	return (0);
121 }
122 
123 static void
124 quicc_setup(struct uart_bas *bas, int baudrate, int databits, int stopbits,
125     int parity)
126 {
127 
128 	if (bas->rclk == 0)
129 		bas->rclk = DEFAULT_RCLK;
130 
131 	/*
132 	 * GSMR_L = 0x00028034
133 	 * GSMR_H = 0x00000020
134 	 */
135 	quicc_param(bas, baudrate, databits, stopbits, parity);
136 
137 	quicc_write2(bas, QUICC_REG_SCC_SCCE(bas->chan - 1), ~0);
138 	quicc_write2(bas, QUICC_REG_SCC_SCCM(bas->chan - 1), 0x0027);
139 }
140 
141 /*
142  * Low-level UART interface.
143  */
144 static int quicc_probe(struct uart_bas *bas);
145 static void quicc_init(struct uart_bas *bas, int, int, int, int);
146 static void quicc_term(struct uart_bas *bas);
147 static void quicc_putc(struct uart_bas *bas, int);
148 static int quicc_rxready(struct uart_bas *bas);
149 static int quicc_getc(struct uart_bas *bas, struct mtx *);
150 
151 static struct uart_ops uart_quicc_ops = {
152 	.probe = quicc_probe,
153 	.init = quicc_init,
154 	.term = quicc_term,
155 	.putc = quicc_putc,
156 	.rxready = quicc_rxready,
157 	.getc = quicc_getc,
158 };
159 
160 static int
161 quicc_probe(struct uart_bas *bas)
162 {
163 
164 	return (0);
165 }
166 
167 static void
168 quicc_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
169     int parity)
170 {
171 
172 	quicc_setup(bas, baudrate, databits, stopbits, parity);
173 }
174 
175 static void
176 quicc_term(struct uart_bas *bas)
177 {
178 }
179 
180 static void
181 quicc_putc(struct uart_bas *bas, int c)
182 {
183 	int unit;
184 	uint16_t toseq;
185 
186 	unit = bas->chan - 1;
187 	while (quicc_read2(bas, QUICC_PRAM_SCC_UART_TOSEQ(unit)) & 0x2000)
188 		DELAY(10);
189 
190 	toseq = 0x2000 | (c & 0xff);
191 	quicc_write2(bas, QUICC_PRAM_SCC_UART_TOSEQ(unit), toseq);
192 }
193 
194 static int
195 quicc_rxready(struct uart_bas *bas)
196 {
197 	uint16_t rb;
198 
199 	rb = quicc_read2(bas, QUICC_PRAM_SCC_RBASE(bas->chan - 1));
200 	return ((quicc_read2(bas, rb) & 0x8000) ? 0 : 1);
201 }
202 
203 static int
204 quicc_getc(struct uart_bas *bas, struct mtx *hwmtx)
205 {
206 	volatile char *buf;
207 	int c;
208 	uint16_t rb, sc;
209 
210 	uart_lock(hwmtx);
211 
212 	rb = quicc_read2(bas, QUICC_PRAM_SCC_RBASE(bas->chan - 1));
213 
214 	while ((sc = quicc_read2(bas, rb)) & 0x8000) {
215 		uart_unlock(hwmtx);
216 		DELAY(4);
217 		uart_lock(hwmtx);
218 	}
219 
220 	buf = (void *)(uintptr_t)quicc_read4(bas, rb + 4);
221 	c = *buf;
222 	quicc_write2(bas, rb, sc | 0x8000);
223 
224 	uart_unlock(hwmtx);
225 
226 	return (c);
227 }
228 
229 /*
230  * High-level UART interface.
231  */
232 struct quicc_softc {
233 	struct uart_softc base;
234 };
235 
236 static int quicc_bus_attach(struct uart_softc *);
237 static int quicc_bus_detach(struct uart_softc *);
238 static int quicc_bus_flush(struct uart_softc *, int);
239 static int quicc_bus_getsig(struct uart_softc *);
240 static int quicc_bus_ioctl(struct uart_softc *, int, intptr_t);
241 static int quicc_bus_ipend(struct uart_softc *);
242 static int quicc_bus_param(struct uart_softc *, int, int, int, int);
243 static int quicc_bus_probe(struct uart_softc *);
244 static int quicc_bus_receive(struct uart_softc *);
245 static int quicc_bus_setsig(struct uart_softc *, int);
246 static int quicc_bus_transmit(struct uart_softc *);
247 static void quicc_bus_grab(struct uart_softc *);
248 static void quicc_bus_ungrab(struct uart_softc *);
249 
250 static kobj_method_t quicc_methods[] = {
251 	KOBJMETHOD(uart_attach,		quicc_bus_attach),
252 	KOBJMETHOD(uart_detach,		quicc_bus_detach),
253 	KOBJMETHOD(uart_flush,		quicc_bus_flush),
254 	KOBJMETHOD(uart_getsig,		quicc_bus_getsig),
255 	KOBJMETHOD(uart_ioctl,		quicc_bus_ioctl),
256 	KOBJMETHOD(uart_ipend,		quicc_bus_ipend),
257 	KOBJMETHOD(uart_param,		quicc_bus_param),
258 	KOBJMETHOD(uart_probe,		quicc_bus_probe),
259 	KOBJMETHOD(uart_receive,	quicc_bus_receive),
260 	KOBJMETHOD(uart_setsig,		quicc_bus_setsig),
261 	KOBJMETHOD(uart_transmit,	quicc_bus_transmit),
262 	KOBJMETHOD(uart_grab,		quicc_bus_grab),
263 	KOBJMETHOD(uart_ungrab,		quicc_bus_ungrab),
264 	{ 0, 0 }
265 };
266 
267 struct uart_class uart_quicc_class = {
268 	"quicc",
269 	quicc_methods,
270 	sizeof(struct quicc_softc),
271 	.uc_ops = &uart_quicc_ops,
272 	.uc_range = 2,
273 	.uc_rclk = DEFAULT_RCLK,
274 	.uc_rshift = 0
275 };
276 UART_CLASS(uart_quicc_class);
277 
278 #define	SIGCHG(c, i, s, d)				\
279 	if (c) {					\
280 		i |= (i & s) ? s : s | d;		\
281 	} else {					\
282 		i = (i & s) ? (i & ~s) | d : i;		\
283 	}
284 
285 static int
286 quicc_bus_attach(struct uart_softc *sc)
287 {
288 	struct uart_bas *bas;
289 	struct uart_devinfo *di;
290 	uint16_t st, rb;
291 
292 	bas = &sc->sc_bas;
293 	if (sc->sc_sysdev != NULL) {
294 		di = sc->sc_sysdev;
295 		quicc_param(bas, di->baudrate, di->databits, di->stopbits,
296 		    di->parity);
297 	} else {
298 		quicc_setup(bas, 9600, 8, 1, UART_PARITY_NONE);
299 	}
300 
301 	/* Enable interrupts on the receive buffer. */
302 	rb = quicc_read2(bas, QUICC_PRAM_SCC_RBASE(bas->chan - 1));
303 	st = quicc_read2(bas, rb);
304 	quicc_write2(bas, rb, st | 0x9000);
305 
306 	(void)quicc_bus_getsig(sc);
307 
308 	return (0);
309 }
310 
311 static int
312 quicc_bus_detach(struct uart_softc *sc)
313 {
314 
315 	return (0);
316 }
317 
318 static int
319 quicc_bus_flush(struct uart_softc *sc, int what)
320 {
321 
322 	return (0);
323 }
324 
325 static int
326 quicc_bus_getsig(struct uart_softc *sc)
327 {
328 	uint32_t new, old, sig;
329 	uint32_t dummy;
330 
331 	do {
332 		old = sc->sc_hwsig;
333 		sig = old;
334 		uart_lock(sc->sc_hwmtx);
335 		/* XXX SIGNALS */
336 		dummy = 0;
337 		uart_unlock(sc->sc_hwmtx);
338 		SIGCHG(dummy, sig, SER_CTS, SER_DCTS);
339 		SIGCHG(dummy, sig, SER_DCD, SER_DDCD);
340 		SIGCHG(dummy, sig, SER_DSR, SER_DDSR);
341 		new = sig & ~SER_MASK_DELTA;
342 	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
343 	return (sig);
344 }
345 
346 static int
347 quicc_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
348 {
349 	struct uart_bas *bas;
350 	uint32_t brg;
351 	int baudrate, error;
352 
353 	bas = &sc->sc_bas;
354 	error = 0;
355 	uart_lock(sc->sc_hwmtx);
356 	switch (request) {
357 	case UART_IOCTL_BREAK:
358 		break;
359 	case UART_IOCTL_BAUD:
360 		brg = quicc_read4(bas, QUICC_REG_BRG(bas->chan - 1)) & 0x1fff;
361 		brg = (brg & 1) ? (brg + 1) << 3 : (brg + 2) >> 1;
362 		baudrate = bas->rclk / (brg * 16);
363 		*(int*)data = baudrate;
364 		break;
365 	default:
366 		error = EINVAL;
367 		break;
368 	}
369 	uart_unlock(sc->sc_hwmtx);
370 	return (error);
371 }
372 
373 static int
374 quicc_bus_ipend(struct uart_softc *sc)
375 {
376 	struct uart_bas *bas;
377 	int ipend;
378 	uint16_t scce;
379 
380 	bas = &sc->sc_bas;
381 	ipend = 0;
382 
383 	uart_lock(sc->sc_hwmtx);
384 	scce = quicc_read2(bas, QUICC_REG_SCC_SCCE(bas->chan - 1));
385 	quicc_write2(bas, QUICC_REG_SCC_SCCE(bas->chan - 1), ~0);
386 	uart_unlock(sc->sc_hwmtx);
387 	if (scce & 0x0001)
388 		ipend |= SER_INT_RXREADY;
389 	if (scce & 0x0002)
390 		ipend |= SER_INT_TXIDLE;
391 	if (scce & 0x0004)
392 		ipend |= SER_INT_OVERRUN;
393 	if (scce & 0x0020)
394 		ipend |= SER_INT_BREAK;
395 	/* XXX SIGNALS */
396 	return (ipend);
397 }
398 
399 static int
400 quicc_bus_param(struct uart_softc *sc, int baudrate, int databits,
401     int stopbits, int parity)
402 {
403 	int error;
404 
405 	uart_lock(sc->sc_hwmtx);
406 	error = quicc_param(&sc->sc_bas, baudrate, databits, stopbits,
407 	    parity);
408 	uart_unlock(sc->sc_hwmtx);
409 	return (error);
410 }
411 
412 static int
413 quicc_bus_probe(struct uart_softc *sc)
414 {
415 	int error;
416 
417 	error = quicc_probe(&sc->sc_bas);
418 	if (error)
419 		return (error);
420 
421 	sc->sc_rxfifosz = 1;
422 	sc->sc_txfifosz = 1;
423 
424 	device_set_descf(sc->sc_dev, "quicc, channel %d", sc->sc_bas.chan);
425 	return (0);
426 }
427 
428 static int
429 quicc_bus_receive(struct uart_softc *sc)
430 {
431 	struct uart_bas *bas;
432 	volatile char *buf;
433 	uint16_t st, rb;
434 
435 	bas = &sc->sc_bas;
436 	uart_lock(sc->sc_hwmtx);
437 	rb = quicc_read2(bas, QUICC_PRAM_SCC_RBASE(bas->chan - 1));
438 	st = quicc_read2(bas, rb);
439 	buf = (void *)(uintptr_t)quicc_read4(bas, rb + 4);
440 	uart_rx_put(sc, *buf);
441 	quicc_write2(bas, rb, st | 0x9000);
442 	uart_unlock(sc->sc_hwmtx);
443 	return (0);
444 }
445 
446 static int
447 quicc_bus_setsig(struct uart_softc *sc, int sig)
448 {
449 	uint32_t new, old;
450 
451 	do {
452 		old = sc->sc_hwsig;
453 		new = old;
454 		if (sig & SER_DDTR) {
455 			SIGCHG(sig & SER_DTR, new, SER_DTR,
456 			    SER_DDTR);
457 		}
458 		if (sig & SER_DRTS) {
459 			SIGCHG(sig & SER_RTS, new, SER_RTS,
460 			    SER_DRTS);
461 		}
462 	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
463 
464 	uart_lock(sc->sc_hwmtx);
465 	/* XXX SIGNALS */
466 	uart_unlock(sc->sc_hwmtx);
467 	return (0);
468 }
469 
470 static int
471 quicc_bus_transmit(struct uart_softc *sc)
472 {
473 	volatile char *buf;
474 	struct uart_bas *bas;
475 	uint16_t st, tb;
476 
477 	bas = &sc->sc_bas;
478 	uart_lock(sc->sc_hwmtx);
479 	tb = quicc_read2(bas, QUICC_PRAM_SCC_TBASE(bas->chan - 1));
480 	st = quicc_read2(bas, tb);
481 	buf = (void *)(uintptr_t)quicc_read4(bas, tb + 4);
482 	*buf = sc->sc_txbuf[0];
483 	quicc_write2(bas, tb + 2, 1);
484 	quicc_write2(bas, tb, st | 0x9000);
485 	sc->sc_txbusy = 1;
486 	uart_unlock(sc->sc_hwmtx);
487 	return (0);
488 }
489 
490 static void
491 quicc_bus_grab(struct uart_softc *sc)
492 {
493 	struct uart_bas *bas;
494 	uint16_t st, rb;
495 
496 	/* Disable interrupts on the receive buffer. */
497 	bas = &sc->sc_bas;
498 	uart_lock(sc->sc_hwmtx);
499 	rb = quicc_read2(bas, QUICC_PRAM_SCC_RBASE(bas->chan - 1));
500 	st = quicc_read2(bas, rb);
501 	quicc_write2(bas, rb, st & ~0x9000);
502 	uart_unlock(sc->sc_hwmtx);
503 }
504 
505 static void
506 quicc_bus_ungrab(struct uart_softc *sc)
507 {
508 	struct uart_bas *bas;
509 	uint16_t st, rb;
510 
511 	/* Enable interrupts on the receive buffer. */
512 	bas = &sc->sc_bas;
513 	uart_lock(sc->sc_hwmtx);
514 	rb = quicc_read2(bas, QUICC_PRAM_SCC_RBASE(bas->chan - 1));
515 	st = quicc_read2(bas, rb);
516 	quicc_write2(bas, rb, st | 0x9000);
517 	uart_unlock(sc->sc_hwmtx);
518 }
519