xref: /freebsd/sys/arm/freescale/vybrid/vf_uart.c (revision ec0e626bafb335b30c499d06066997f54b10c092)
1 /*-
2  * Copyright (c) 2013 Ruslan Bukin <br@bsdpad.com>
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 /*
28  * Vybrid Family Universal Asynchronous Receiver/Transmitter
29  * Chapter 49, Vybrid Reference Manual, Rev. 5, 07/2013
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include "opt_ddb.h"
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/bus.h>
40 #include <sys/conf.h>
41 #include <sys/kdb.h>
42 #include <machine/bus.h>
43 #include <machine/fdt.h>
44 
45 #include <dev/uart/uart.h>
46 #include <dev/uart/uart_cpu.h>
47 #include <dev/uart/uart_cpu_fdt.h>
48 #include <dev/uart/uart_bus.h>
49 
50 #include "uart_if.h"
51 
52 #define	UART_BDH	0x00	/* Baud Rate Registers: High */
53 #define	UART_BDL	0x01	/* Baud Rate Registers: Low */
54 #define	UART_C1		0x02	/* Control Register 1 */
55 #define	UART_C2		0x03	/* Control Register 2 */
56 #define	UART_S1		0x04	/* Status Register 1 */
57 #define	UART_S2		0x05	/* Status Register 2 */
58 #define	UART_C3		0x06	/* Control Register 3 */
59 #define	UART_D		0x07	/* Data Register */
60 #define	UART_MA1	0x08	/* Match Address Registers 1 */
61 #define	UART_MA2	0x09	/* Match Address Registers 2 */
62 #define	UART_C4		0x0A	/* Control Register 4 */
63 #define	UART_C5		0x0B	/* Control Register 5 */
64 #define	UART_ED		0x0C	/* Extended Data Register */
65 #define	UART_MODEM	0x0D	/* Modem Register */
66 #define	UART_IR		0x0E	/* Infrared Register */
67 #define	UART_PFIFO	0x10	/* FIFO Parameters */
68 #define	UART_CFIFO	0x11	/* FIFO Control Register */
69 #define	UART_SFIFO	0x12	/* FIFO Status Register */
70 #define	UART_TWFIFO	0x13	/* FIFO Transmit Watermark */
71 #define	UART_TCFIFO	0x14	/* FIFO Transmit Count */
72 #define	UART_RWFIFO	0x15	/* FIFO Receive Watermark */
73 #define	UART_RCFIFO	0x16	/* FIFO Receive Count */
74 #define	UART_C7816	0x18	/* 7816 Control Register */
75 #define	UART_IE7816	0x19	/* 7816 Interrupt Enable Register */
76 #define	UART_IS7816	0x1A	/* 7816 Interrupt Status Register */
77 #define	UART_WP7816T0	0x1B	/* 7816 Wait Parameter Register */
78 #define	UART_WP7816T1	0x1B	/* 7816 Wait Parameter Register */
79 #define	UART_WN7816	0x1C	/* 7816 Wait N Register */
80 #define	UART_WF7816	0x1D	/* 7816 Wait FD Register */
81 #define	UART_ET7816	0x1E	/* 7816 Error Threshold Register */
82 #define	UART_TL7816	0x1F	/* 7816 Transmit Length Register */
83 #define	UART_C6		0x21	/* CEA709.1-B Control Register 6 */
84 #define	UART_PCTH	0x22	/* CEA709.1-B Packet Cycle Time Counter High */
85 #define	UART_PCTL	0x23	/* CEA709.1-B Packet Cycle Time Counter Low */
86 #define	UART_B1T	0x24	/* CEA709.1-B Beta1 Timer */
87 #define	UART_SDTH	0x25	/* CEA709.1-B Secondary Delay Timer High */
88 #define	UART_SDTL	0x26	/* CEA709.1-B Secondary Delay Timer Low */
89 #define	UART_PRE	0x27	/* CEA709.1-B Preamble */
90 #define	UART_TPL	0x28	/* CEA709.1-B Transmit Packet Length */
91 #define	UART_IE		0x29	/* CEA709.1-B Interrupt Enable Register */
92 #define	UART_WB		0x2A	/* CEA709.1-B WBASE */
93 #define	UART_S3		0x2B	/* CEA709.1-B Status Register */
94 #define	UART_S4		0x2C	/* CEA709.1-B Status Register */
95 #define	UART_RPL	0x2D	/* CEA709.1-B Received Packet Length */
96 #define	UART_RPREL	0x2E	/* CEA709.1-B Received Preamble Length */
97 #define	UART_CPW	0x2F	/* CEA709.1-B Collision Pulse Width */
98 #define	UART_RIDT	0x30	/* CEA709.1-B Receive Indeterminate Time */
99 #define	UART_TIDT	0x31	/* CEA709.1-B Transmit Indeterminate Time */
100 
101 #define	UART_C2_TE	(1 << 3)	/* Transmitter Enable */
102 #define	UART_C2_TIE	(1 << 7)	/* Transmitter Interrupt Enable */
103 #define	UART_C2_RE	(1 << 2)	/* Receiver Enable */
104 #define	UART_C2_RIE	(1 << 5)	/* Receiver Interrupt Enable */
105 #define	UART_S1_TDRE	(1 << 7)	/* Transmit Data Register Empty Flag */
106 #define	UART_S1_RDRF	(1 << 5)	/* Receive Data Register Full Flag */
107 #define	UART_S2_LBKDIF	(1 << 7)	/* LIN Break Detect Interrupt Flag */
108 
109 #define	UART_C4_BRFA	0x1f	/* Baud Rate Fine Adjust */
110 #define	UART_BDH_SBR	0x1f	/* UART Baud Rate Bits */
111 
112 /*
113  * Low-level UART interface.
114  */
115 static int vf_uart_probe(struct uart_bas *bas);
116 static void vf_uart_init(struct uart_bas *bas, int, int, int, int);
117 static void vf_uart_term(struct uart_bas *bas);
118 static void vf_uart_putc(struct uart_bas *bas, int);
119 static int vf_uart_rxready(struct uart_bas *bas);
120 static int vf_uart_getc(struct uart_bas *bas, struct mtx *);
121 
122 void uart_reinit(struct uart_softc *,int,int);
123 
124 static struct uart_ops uart_vybrid_ops = {
125 	.probe = vf_uart_probe,
126 	.init = vf_uart_init,
127 	.term = vf_uart_term,
128 	.putc = vf_uart_putc,
129 	.rxready = vf_uart_rxready,
130 	.getc = vf_uart_getc,
131 };
132 
133 static int
134 vf_uart_probe(struct uart_bas *bas)
135 {
136 
137 	return (0);
138 }
139 
140 static void
141 vf_uart_init(struct uart_bas *bas, int baudrate, int databits,
142     int stopbits, int parity)
143 {
144 
145 }
146 
147 static void
148 vf_uart_term(struct uart_bas *bas)
149 {
150 
151 }
152 
153 static void
154 vf_uart_putc(struct uart_bas *bas, int c)
155 {
156 
157 	while (!(uart_getreg(bas, UART_S1) & UART_S1_TDRE))
158 		;
159 
160 	uart_setreg(bas, UART_D, c);
161 }
162 
163 static int
164 vf_uart_rxready(struct uart_bas *bas)
165 {
166 	int usr1;
167 
168 	usr1 = uart_getreg(bas, UART_S1);
169 	if (usr1 & UART_S1_RDRF) {
170 		return (1);
171 	}
172 
173 	return (0);
174 }
175 
176 static int
177 vf_uart_getc(struct uart_bas *bas, struct mtx *hwmtx)
178 {
179 	int c;
180 
181 	uart_lock(hwmtx);
182 
183 	while (!(uart_getreg(bas, UART_S1) & UART_S1_RDRF))
184 		;
185 
186 	c = uart_getreg(bas, UART_D);
187 	uart_unlock(hwmtx);
188 
189 	return (c & 0xff);
190 }
191 
192 /*
193  * High-level UART interface.
194  */
195 struct vf_uart_softc {
196 	struct uart_softc base;
197 };
198 
199 void
200 uart_reinit(struct uart_softc *sc, int clkspeed, int baud)
201 {
202 	struct uart_bas *bas;
203 	int sbr;
204 	int brfa;
205 	int reg;
206 
207 	bas = &sc->sc_bas;
208 	if (!bas) {
209 		printf("Error: cant reconfigure bas\n");
210 		return;
211 	}
212 
213 	uart_setreg(bas, UART_MODEM, 0x00);
214 
215 	/*
216 	 * Disable transmitter and receiver
217 	 * for a while.
218 	 */
219 	reg = uart_getreg(bas, UART_C2);
220 	reg &= ~(UART_C2_RE | UART_C2_TE);
221 	uart_setreg(bas, UART_C2, 0x00);
222 
223 	uart_setreg(bas, UART_C1, 0x00);
224 
225 	sbr = (uint16_t) (clkspeed / (baud * 16));
226 	brfa = (clkspeed / baud) - (sbr * 16);
227 
228 	reg = uart_getreg(bas, UART_BDH);
229 	reg &= ~UART_BDH_SBR;
230 	reg |= ((sbr & 0x1f00) >> 8);
231 	uart_setreg(bas, UART_BDH, reg);
232 
233 	reg = sbr & 0x00ff;
234 	uart_setreg(bas, UART_BDL, reg);
235 
236 	reg = uart_getreg(bas, UART_C4);
237 	reg &= ~UART_C4_BRFA;
238 	reg |= (brfa & UART_C4_BRFA);
239 	uart_setreg(bas, UART_C4, reg);
240 
241 	reg = uart_getreg(bas, UART_C2);
242 	reg |= (UART_C2_RE | UART_C2_TE);
243 	uart_setreg(bas, UART_C2, reg);
244 
245 }
246 
247 static int vf_uart_bus_attach(struct uart_softc *);
248 static int vf_uart_bus_detach(struct uart_softc *);
249 static int vf_uart_bus_flush(struct uart_softc *, int);
250 static int vf_uart_bus_getsig(struct uart_softc *);
251 static int vf_uart_bus_ioctl(struct uart_softc *, int, intptr_t);
252 static int vf_uart_bus_ipend(struct uart_softc *);
253 static int vf_uart_bus_param(struct uart_softc *, int, int, int, int);
254 static int vf_uart_bus_probe(struct uart_softc *);
255 static int vf_uart_bus_receive(struct uart_softc *);
256 static int vf_uart_bus_setsig(struct uart_softc *, int);
257 static int vf_uart_bus_transmit(struct uart_softc *);
258 
259 static kobj_method_t vf_uart_methods[] = {
260 	KOBJMETHOD(uart_attach,		vf_uart_bus_attach),
261 	KOBJMETHOD(uart_detach,		vf_uart_bus_detach),
262 	KOBJMETHOD(uart_flush,		vf_uart_bus_flush),
263 	KOBJMETHOD(uart_getsig,		vf_uart_bus_getsig),
264 	KOBJMETHOD(uart_ioctl,		vf_uart_bus_ioctl),
265 	KOBJMETHOD(uart_ipend,		vf_uart_bus_ipend),
266 	KOBJMETHOD(uart_param,		vf_uart_bus_param),
267 	KOBJMETHOD(uart_probe,		vf_uart_bus_probe),
268 	KOBJMETHOD(uart_receive,	vf_uart_bus_receive),
269 	KOBJMETHOD(uart_setsig,		vf_uart_bus_setsig),
270 	KOBJMETHOD(uart_transmit,	vf_uart_bus_transmit),
271 	{ 0, 0 }
272 };
273 
274 static struct uart_class uart_vybrid_class = {
275 	"vybrid",
276 	vf_uart_methods,
277 	sizeof(struct vf_uart_softc),
278 	.uc_ops = &uart_vybrid_ops,
279 	.uc_range = 0x100,
280 	.uc_rclk = 24000000 /* TODO: get value from CCM */
281 };
282 
283 static struct ofw_compat_data compat_data[] = {
284 	{"fsl,mvf600-uart",	(uintptr_t)&uart_vybrid_class},
285 	{NULL,			(uintptr_t)NULL},
286 };
287 UART_FDT_CLASS_AND_DEVICE(compat_data);
288 
289 static int
290 vf_uart_bus_attach(struct uart_softc *sc)
291 {
292 	struct uart_bas *bas;
293 	int reg;
294 
295 	bas = &sc->sc_bas;
296 
297 	sc->sc_hwiflow = 0;
298 	sc->sc_hwoflow = 0;
299 
300 	uart_reinit(sc, 66000000, 115200);
301 
302 	reg = uart_getreg(bas, UART_C2);
303 	if (sc->sc_sysdev != NULL && sc->sc_sysdev->type == UART_DEV_CONSOLE) {
304 		reg &= ~UART_C2_RIE;
305 	} else {
306 		reg |= UART_C2_RIE;
307 	}
308 	uart_setreg(bas, UART_C2, reg);
309 
310 	return (0);
311 }
312 
313 static int
314 vf_uart_bus_detach(struct uart_softc *sc)
315 {
316 
317 	/* TODO */
318 	return (0);
319 }
320 
321 static int
322 vf_uart_bus_flush(struct uart_softc *sc, int what)
323 {
324 
325 	/* TODO */
326 	return (0);
327 }
328 
329 static int
330 vf_uart_bus_getsig(struct uart_softc *sc)
331 {
332 
333 	/* TODO */
334 	return (0);
335 }
336 
337 static int
338 vf_uart_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
339 {
340 	struct uart_bas *bas;
341 	int error;
342 
343 	bas = &sc->sc_bas;
344 	error = 0;
345 	uart_lock(sc->sc_hwmtx);
346 	switch (request) {
347 	case UART_IOCTL_BREAK:
348 	/* TODO */
349 		break;
350 	case UART_IOCTL_BAUD:
351 	/* TODO */
352 		*(int*)data = 115200;
353 		break;
354 	default:
355 		error = EINVAL;
356 		break;
357 	}
358 	uart_unlock(sc->sc_hwmtx);
359 
360 	return (error);
361 }
362 
363 static int
364 vf_uart_bus_ipend(struct uart_softc *sc)
365 {
366 	struct uart_bas *bas;
367 	int ipend;
368 	uint32_t usr1, usr2;
369 	int reg;
370 	int sfifo;
371 
372 	bas = &sc->sc_bas;
373 	ipend = 0;
374 
375 	uart_lock(sc->sc_hwmtx);
376 
377 	usr1 = uart_getreg(bas, UART_S1);
378 	usr2 = uart_getreg(bas, UART_S2);
379 	sfifo = uart_getreg(bas, UART_SFIFO);
380 
381 	/* ack usr2 */
382 	uart_setreg(bas, UART_S2, usr2);
383 
384 	if (usr1 & UART_S1_TDRE) {
385 		reg = uart_getreg(bas, UART_C2);
386 		reg &= ~(UART_C2_TIE);
387 		uart_setreg(bas, UART_C2, reg);
388 
389 		if (sc->sc_txbusy != 0) {
390 			ipend |= SER_INT_TXIDLE;
391 		}
392 	}
393 
394 	if (usr1 & UART_S1_RDRF) {
395 		reg = uart_getreg(bas, UART_C2);
396 		reg &= ~(UART_C2_RIE);
397 		uart_setreg(bas, UART_C2, reg);
398 
399 		ipend |= SER_INT_RXREADY;
400 	}
401 
402 	if (usr2 & UART_S2_LBKDIF) {
403 		ipend |= SER_INT_BREAK;
404 	}
405 
406 	uart_unlock(sc->sc_hwmtx);
407 
408 	return (ipend);
409 }
410 
411 static int
412 vf_uart_bus_param(struct uart_softc *sc, int baudrate, int databits,
413     int stopbits, int parity)
414 {
415 
416 	uart_lock(sc->sc_hwmtx);
417 	vf_uart_init(&sc->sc_bas, baudrate, databits, stopbits, parity);
418 	uart_unlock(sc->sc_hwmtx);
419 
420 	return (0);
421 }
422 
423 static int
424 vf_uart_bus_probe(struct uart_softc *sc)
425 {
426 	int error;
427 
428 	error = vf_uart_probe(&sc->sc_bas);
429 	if (error)
430 		return (error);
431 
432 	sc->sc_rxfifosz = 1;
433 	sc->sc_txfifosz = 1;
434 
435 	device_set_desc(sc->sc_dev, "Vybrid Family UART");
436 	return (0);
437 }
438 
439 static int
440 vf_uart_bus_receive(struct uart_softc *sc)
441 {
442 	struct uart_bas *bas;
443 	int reg;
444 	int c;
445 
446 	bas = &sc->sc_bas;
447 	uart_lock(sc->sc_hwmtx);
448 
449 	/* Read FIFO */
450 	while (uart_getreg(bas, UART_S1) & UART_S1_RDRF) {
451 		if (uart_rx_full(sc)) {
452 		/* No space left in input buffer */
453 			sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
454 			break;
455 		}
456 
457 		c = uart_getreg(bas, UART_D);
458 		uart_rx_put(sc, c);
459 	}
460 
461 	/* Reenable Data Ready interrupt */
462 	reg = uart_getreg(bas, UART_C2);
463 	reg |= (UART_C2_RIE);
464 	uart_setreg(bas, UART_C2, reg);
465 
466 	uart_unlock(sc->sc_hwmtx);
467 	return (0);
468 }
469 
470 static int
471 vf_uart_bus_setsig(struct uart_softc *sc, int sig)
472 {
473 	struct uart_bas *bas;
474 	int reg;
475 
476 	/* TODO: implement (?) */
477 
478 	/* XXX workaround to have working console on mount prompt */
479 	/* Enable RX interrupt */
480 	bas = &sc->sc_bas;
481 	if (sc->sc_sysdev != NULL && sc->sc_sysdev->type == UART_DEV_CONSOLE) {
482 		reg = uart_getreg(bas, UART_C2);
483 		reg |= (UART_C2_RIE);
484 		uart_setreg(bas, UART_C2, reg);
485 	}
486 
487 	return (0);
488 }
489 
490 static int
491 vf_uart_bus_transmit(struct uart_softc *sc)
492 {
493 	struct uart_bas *bas = &sc->sc_bas;
494 	int i;
495 	int reg;
496 
497 	bas = &sc->sc_bas;
498 	uart_lock(sc->sc_hwmtx);
499 
500 	/* Fill TX FIFO */
501 	for (i = 0; i < sc->sc_txdatasz; i++) {
502 		uart_setreg(bas, UART_D, sc->sc_txbuf[i] & 0xff);
503 		uart_barrier(&sc->sc_bas);
504 	}
505 
506 	sc->sc_txbusy = 1;
507 
508 	/* Call me when ready */
509 	reg = uart_getreg(bas, UART_C2);
510 	reg |= (UART_C2_TIE);
511 	uart_setreg(bas, UART_C2, reg);
512 
513 	uart_unlock(sc->sc_hwmtx);
514 
515 	return (0);
516 }
517