xref: /freebsd/sys/arm/freescale/vybrid/vf_uart.c (revision f305e6eaf8d98d9c2ca7ca97791e84521f25b801)
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 
44 #include <dev/uart/uart.h>
45 #include <dev/uart/uart_cpu.h>
46 #include <dev/uart/uart_cpu_fdt.h>
47 #include <dev/uart/uart_bus.h>
48 
49 #include "uart_if.h"
50 
51 #define	UART_BDH	0x00	/* Baud Rate Registers: High */
52 #define	UART_BDL	0x01	/* Baud Rate Registers: Low */
53 #define	UART_C1		0x02	/* Control Register 1 */
54 #define	UART_C2		0x03	/* Control Register 2 */
55 #define	UART_S1		0x04	/* Status Register 1 */
56 #define	UART_S2		0x05	/* Status Register 2 */
57 #define	UART_C3		0x06	/* Control Register 3 */
58 #define	UART_D		0x07	/* Data Register */
59 #define	UART_MA1	0x08	/* Match Address Registers 1 */
60 #define	UART_MA2	0x09	/* Match Address Registers 2 */
61 #define	UART_C4		0x0A	/* Control Register 4 */
62 #define	UART_C5		0x0B	/* Control Register 5 */
63 #define	UART_ED		0x0C	/* Extended Data Register */
64 #define	UART_MODEM	0x0D	/* Modem Register */
65 #define	UART_IR		0x0E	/* Infrared Register */
66 #define	UART_PFIFO	0x10	/* FIFO Parameters */
67 #define	UART_CFIFO	0x11	/* FIFO Control Register */
68 #define	UART_SFIFO	0x12	/* FIFO Status Register */
69 #define	UART_TWFIFO	0x13	/* FIFO Transmit Watermark */
70 #define	UART_TCFIFO	0x14	/* FIFO Transmit Count */
71 #define	UART_RWFIFO	0x15	/* FIFO Receive Watermark */
72 #define	UART_RCFIFO	0x16	/* FIFO Receive Count */
73 #define	UART_C7816	0x18	/* 7816 Control Register */
74 #define	UART_IE7816	0x19	/* 7816 Interrupt Enable Register */
75 #define	UART_IS7816	0x1A	/* 7816 Interrupt Status Register */
76 #define	UART_WP7816T0	0x1B	/* 7816 Wait Parameter Register */
77 #define	UART_WP7816T1	0x1B	/* 7816 Wait Parameter Register */
78 #define	UART_WN7816	0x1C	/* 7816 Wait N Register */
79 #define	UART_WF7816	0x1D	/* 7816 Wait FD Register */
80 #define	UART_ET7816	0x1E	/* 7816 Error Threshold Register */
81 #define	UART_TL7816	0x1F	/* 7816 Transmit Length Register */
82 #define	UART_C6		0x21	/* CEA709.1-B Control Register 6 */
83 #define	UART_PCTH	0x22	/* CEA709.1-B Packet Cycle Time Counter High */
84 #define	UART_PCTL	0x23	/* CEA709.1-B Packet Cycle Time Counter Low */
85 #define	UART_B1T	0x24	/* CEA709.1-B Beta1 Timer */
86 #define	UART_SDTH	0x25	/* CEA709.1-B Secondary Delay Timer High */
87 #define	UART_SDTL	0x26	/* CEA709.1-B Secondary Delay Timer Low */
88 #define	UART_PRE	0x27	/* CEA709.1-B Preamble */
89 #define	UART_TPL	0x28	/* CEA709.1-B Transmit Packet Length */
90 #define	UART_IE		0x29	/* CEA709.1-B Interrupt Enable Register */
91 #define	UART_WB		0x2A	/* CEA709.1-B WBASE */
92 #define	UART_S3		0x2B	/* CEA709.1-B Status Register */
93 #define	UART_S4		0x2C	/* CEA709.1-B Status Register */
94 #define	UART_RPL	0x2D	/* CEA709.1-B Received Packet Length */
95 #define	UART_RPREL	0x2E	/* CEA709.1-B Received Preamble Length */
96 #define	UART_CPW	0x2F	/* CEA709.1-B Collision Pulse Width */
97 #define	UART_RIDT	0x30	/* CEA709.1-B Receive Indeterminate Time */
98 #define	UART_TIDT	0x31	/* CEA709.1-B Transmit Indeterminate Time */
99 
100 #define	UART_C2_TE	(1 << 3)	/* Transmitter Enable */
101 #define	UART_C2_TIE	(1 << 7)	/* Transmitter Interrupt Enable */
102 #define	UART_C2_RE	(1 << 2)	/* Receiver Enable */
103 #define	UART_C2_RIE	(1 << 5)	/* Receiver Interrupt Enable */
104 #define	UART_S1_TDRE	(1 << 7)	/* Transmit Data Register Empty Flag */
105 #define	UART_S1_RDRF	(1 << 5)	/* Receive Data Register Full Flag */
106 #define	UART_S2_LBKDIF	(1 << 7)	/* LIN Break Detect Interrupt Flag */
107 
108 #define	UART_C4_BRFA	0x1f	/* Baud Rate Fine Adjust */
109 #define	UART_BDH_SBR	0x1f	/* UART Baud Rate Bits */
110 
111 /*
112  * Low-level UART interface.
113  */
114 static int vf_uart_probe(struct uart_bas *bas);
115 static void vf_uart_init(struct uart_bas *bas, int, int, int, int);
116 static void vf_uart_term(struct uart_bas *bas);
117 static void vf_uart_putc(struct uart_bas *bas, int);
118 static int vf_uart_rxready(struct uart_bas *bas);
119 static int vf_uart_getc(struct uart_bas *bas, struct mtx *);
120 
121 void uart_reinit(struct uart_softc *,int,int);
122 
123 static struct uart_ops uart_vybrid_ops = {
124 	.probe = vf_uart_probe,
125 	.init = vf_uart_init,
126 	.term = vf_uart_term,
127 	.putc = vf_uart_putc,
128 	.rxready = vf_uart_rxready,
129 	.getc = vf_uart_getc,
130 };
131 
132 static int
133 vf_uart_probe(struct uart_bas *bas)
134 {
135 
136 	return (0);
137 }
138 
139 static void
140 vf_uart_init(struct uart_bas *bas, int baudrate, int databits,
141     int stopbits, int parity)
142 {
143 
144 }
145 
146 static void
147 vf_uart_term(struct uart_bas *bas)
148 {
149 
150 }
151 
152 static void
153 vf_uart_putc(struct uart_bas *bas, int c)
154 {
155 
156 	while (!(uart_getreg(bas, UART_S1) & UART_S1_TDRE))
157 		;
158 
159 	uart_setreg(bas, UART_D, c);
160 }
161 
162 static int
163 vf_uart_rxready(struct uart_bas *bas)
164 {
165 	int usr1;
166 
167 	usr1 = uart_getreg(bas, UART_S1);
168 	if (usr1 & UART_S1_RDRF) {
169 		return (1);
170 	}
171 
172 	return (0);
173 }
174 
175 static int
176 vf_uart_getc(struct uart_bas *bas, struct mtx *hwmtx)
177 {
178 	int c;
179 
180 	uart_lock(hwmtx);
181 
182 	while (!(uart_getreg(bas, UART_S1) & UART_S1_RDRF))
183 		;
184 
185 	c = uart_getreg(bas, UART_D);
186 	uart_unlock(hwmtx);
187 
188 	return (c & 0xff);
189 }
190 
191 /*
192  * High-level UART interface.
193  */
194 struct vf_uart_softc {
195 	struct uart_softc base;
196 };
197 
198 void
199 uart_reinit(struct uart_softc *sc, int clkspeed, int baud)
200 {
201 	struct uart_bas *bas;
202 	int sbr;
203 	int brfa;
204 	int reg;
205 
206 	bas = &sc->sc_bas;
207 	if (!bas) {
208 		printf("Error: cant reconfigure bas\n");
209 		return;
210 	}
211 
212 	uart_setreg(bas, UART_MODEM, 0x00);
213 
214 	/*
215 	 * Disable transmitter and receiver
216 	 * for a while.
217 	 */
218 	reg = uart_getreg(bas, UART_C2);
219 	reg &= ~(UART_C2_RE | UART_C2_TE);
220 	uart_setreg(bas, UART_C2, 0x00);
221 
222 	uart_setreg(bas, UART_C1, 0x00);
223 
224 	sbr = (uint16_t) (clkspeed / (baud * 16));
225 	brfa = (clkspeed / baud) - (sbr * 16);
226 
227 	reg = uart_getreg(bas, UART_BDH);
228 	reg &= ~UART_BDH_SBR;
229 	reg |= ((sbr & 0x1f00) >> 8);
230 	uart_setreg(bas, UART_BDH, reg);
231 
232 	reg = sbr & 0x00ff;
233 	uart_setreg(bas, UART_BDL, reg);
234 
235 	reg = uart_getreg(bas, UART_C4);
236 	reg &= ~UART_C4_BRFA;
237 	reg |= (brfa & UART_C4_BRFA);
238 	uart_setreg(bas, UART_C4, reg);
239 
240 	reg = uart_getreg(bas, UART_C2);
241 	reg |= (UART_C2_RE | UART_C2_TE);
242 	uart_setreg(bas, UART_C2, reg);
243 
244 }
245 
246 static int vf_uart_bus_attach(struct uart_softc *);
247 static int vf_uart_bus_detach(struct uart_softc *);
248 static int vf_uart_bus_flush(struct uart_softc *, int);
249 static int vf_uart_bus_getsig(struct uart_softc *);
250 static int vf_uart_bus_ioctl(struct uart_softc *, int, intptr_t);
251 static int vf_uart_bus_ipend(struct uart_softc *);
252 static int vf_uart_bus_param(struct uart_softc *, int, int, int, int);
253 static int vf_uart_bus_probe(struct uart_softc *);
254 static int vf_uart_bus_receive(struct uart_softc *);
255 static int vf_uart_bus_setsig(struct uart_softc *, int);
256 static int vf_uart_bus_transmit(struct uart_softc *);
257 
258 static kobj_method_t vf_uart_methods[] = {
259 	KOBJMETHOD(uart_attach,		vf_uart_bus_attach),
260 	KOBJMETHOD(uart_detach,		vf_uart_bus_detach),
261 	KOBJMETHOD(uart_flush,		vf_uart_bus_flush),
262 	KOBJMETHOD(uart_getsig,		vf_uart_bus_getsig),
263 	KOBJMETHOD(uart_ioctl,		vf_uart_bus_ioctl),
264 	KOBJMETHOD(uart_ipend,		vf_uart_bus_ipend),
265 	KOBJMETHOD(uart_param,		vf_uart_bus_param),
266 	KOBJMETHOD(uart_probe,		vf_uart_bus_probe),
267 	KOBJMETHOD(uart_receive,	vf_uart_bus_receive),
268 	KOBJMETHOD(uart_setsig,		vf_uart_bus_setsig),
269 	KOBJMETHOD(uart_transmit,	vf_uart_bus_transmit),
270 	{ 0, 0 }
271 };
272 
273 static struct uart_class uart_vybrid_class = {
274 	"vybrid",
275 	vf_uart_methods,
276 	sizeof(struct vf_uart_softc),
277 	.uc_ops = &uart_vybrid_ops,
278 	.uc_range = 0x100,
279 	.uc_rclk = 24000000 /* TODO: get value from CCM */
280 };
281 
282 static struct ofw_compat_data compat_data[] = {
283 	{"fsl,mvf600-uart",	(uintptr_t)&uart_vybrid_class},
284 	{NULL,			(uintptr_t)NULL},
285 };
286 UART_FDT_CLASS_AND_DEVICE(compat_data);
287 
288 static int
289 vf_uart_bus_attach(struct uart_softc *sc)
290 {
291 	struct uart_bas *bas;
292 	int reg;
293 
294 	bas = &sc->sc_bas;
295 
296 	sc->sc_hwiflow = 0;
297 	sc->sc_hwoflow = 0;
298 
299 	uart_reinit(sc, 66000000, 115200);
300 
301 	reg = uart_getreg(bas, UART_C2);
302 	if (sc->sc_sysdev != NULL && sc->sc_sysdev->type == UART_DEV_CONSOLE) {
303 		reg &= ~UART_C2_RIE;
304 	} else {
305 		reg |= UART_C2_RIE;
306 	}
307 	uart_setreg(bas, UART_C2, reg);
308 
309 	return (0);
310 }
311 
312 static int
313 vf_uart_bus_detach(struct uart_softc *sc)
314 {
315 
316 	/* TODO */
317 	return (0);
318 }
319 
320 static int
321 vf_uart_bus_flush(struct uart_softc *sc, int what)
322 {
323 
324 	/* TODO */
325 	return (0);
326 }
327 
328 static int
329 vf_uart_bus_getsig(struct uart_softc *sc)
330 {
331 
332 	/* TODO */
333 	return (0);
334 }
335 
336 static int
337 vf_uart_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
338 {
339 	struct uart_bas *bas;
340 	int error;
341 
342 	bas = &sc->sc_bas;
343 	error = 0;
344 	uart_lock(sc->sc_hwmtx);
345 	switch (request) {
346 	case UART_IOCTL_BREAK:
347 	/* TODO */
348 		break;
349 	case UART_IOCTL_BAUD:
350 	/* TODO */
351 		*(int*)data = 115200;
352 		break;
353 	default:
354 		error = EINVAL;
355 		break;
356 	}
357 	uart_unlock(sc->sc_hwmtx);
358 
359 	return (error);
360 }
361 
362 static int
363 vf_uart_bus_ipend(struct uart_softc *sc)
364 {
365 	struct uart_bas *bas;
366 	int ipend;
367 	uint32_t usr1, usr2;
368 	int reg;
369 	int sfifo;
370 
371 	bas = &sc->sc_bas;
372 	ipend = 0;
373 
374 	uart_lock(sc->sc_hwmtx);
375 
376 	usr1 = uart_getreg(bas, UART_S1);
377 	usr2 = uart_getreg(bas, UART_S2);
378 	sfifo = uart_getreg(bas, UART_SFIFO);
379 
380 	/* ack usr2 */
381 	uart_setreg(bas, UART_S2, usr2);
382 
383 	if (usr1 & UART_S1_TDRE) {
384 		reg = uart_getreg(bas, UART_C2);
385 		reg &= ~(UART_C2_TIE);
386 		uart_setreg(bas, UART_C2, reg);
387 
388 		if (sc->sc_txbusy != 0) {
389 			ipend |= SER_INT_TXIDLE;
390 		}
391 	}
392 
393 	if (usr1 & UART_S1_RDRF) {
394 		reg = uart_getreg(bas, UART_C2);
395 		reg &= ~(UART_C2_RIE);
396 		uart_setreg(bas, UART_C2, reg);
397 
398 		ipend |= SER_INT_RXREADY;
399 	}
400 
401 	if (usr2 & UART_S2_LBKDIF) {
402 		ipend |= SER_INT_BREAK;
403 	}
404 
405 	uart_unlock(sc->sc_hwmtx);
406 
407 	return (ipend);
408 }
409 
410 static int
411 vf_uart_bus_param(struct uart_softc *sc, int baudrate, int databits,
412     int stopbits, int parity)
413 {
414 
415 	uart_lock(sc->sc_hwmtx);
416 	vf_uart_init(&sc->sc_bas, baudrate, databits, stopbits, parity);
417 	uart_unlock(sc->sc_hwmtx);
418 
419 	return (0);
420 }
421 
422 static int
423 vf_uart_bus_probe(struct uart_softc *sc)
424 {
425 	int error;
426 
427 	error = vf_uart_probe(&sc->sc_bas);
428 	if (error)
429 		return (error);
430 
431 	sc->sc_rxfifosz = 1;
432 	sc->sc_txfifosz = 1;
433 
434 	device_set_desc(sc->sc_dev, "Vybrid Family UART");
435 	return (0);
436 }
437 
438 static int
439 vf_uart_bus_receive(struct uart_softc *sc)
440 {
441 	struct uart_bas *bas;
442 	int reg;
443 	int c;
444 
445 	bas = &sc->sc_bas;
446 	uart_lock(sc->sc_hwmtx);
447 
448 	/* Read FIFO */
449 	while (uart_getreg(bas, UART_S1) & UART_S1_RDRF) {
450 		if (uart_rx_full(sc)) {
451 		/* No space left in input buffer */
452 			sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
453 			break;
454 		}
455 
456 		c = uart_getreg(bas, UART_D);
457 		uart_rx_put(sc, c);
458 	}
459 
460 	/* Reenable Data Ready interrupt */
461 	reg = uart_getreg(bas, UART_C2);
462 	reg |= (UART_C2_RIE);
463 	uart_setreg(bas, UART_C2, reg);
464 
465 	uart_unlock(sc->sc_hwmtx);
466 	return (0);
467 }
468 
469 static int
470 vf_uart_bus_setsig(struct uart_softc *sc, int sig)
471 {
472 	struct uart_bas *bas;
473 	int reg;
474 
475 	/* TODO: implement (?) */
476 
477 	/* XXX workaround to have working console on mount prompt */
478 	/* Enable RX interrupt */
479 	bas = &sc->sc_bas;
480 	if (sc->sc_sysdev != NULL && sc->sc_sysdev->type == UART_DEV_CONSOLE) {
481 		reg = uart_getreg(bas, UART_C2);
482 		reg |= (UART_C2_RIE);
483 		uart_setreg(bas, UART_C2, reg);
484 	}
485 
486 	return (0);
487 }
488 
489 static int
490 vf_uart_bus_transmit(struct uart_softc *sc)
491 {
492 	struct uart_bas *bas = &sc->sc_bas;
493 	int i;
494 	int reg;
495 
496 	bas = &sc->sc_bas;
497 	uart_lock(sc->sc_hwmtx);
498 
499 	/* Fill TX FIFO */
500 	for (i = 0; i < sc->sc_txdatasz; i++) {
501 		uart_setreg(bas, UART_D, sc->sc_txbuf[i] & 0xff);
502 		uart_barrier(&sc->sc_bas);
503 	}
504 
505 	sc->sc_txbusy = 1;
506 
507 	/* Call me when ready */
508 	reg = uart_getreg(bas, UART_C2);
509 	reg |= (UART_C2_TIE);
510 	uart_setreg(bas, UART_C2, reg);
511 
512 	uart_unlock(sc->sc_hwmtx);
513 
514 	return (0);
515 }
516