xref: /freebsd/sys/arm/freescale/vybrid/vf_uart.c (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2013 Ruslan Bukin <br@bsdpad.com>
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  * 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 AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 /*
30  * Vybrid Family Universal Asynchronous Receiver/Transmitter
31  * Chapter 49, Vybrid Reference Manual, Rev. 5, 07/2013
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include "opt_ddb.h"
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/bus.h>
42 #include <sys/conf.h>
43 #include <sys/kdb.h>
44 #include <machine/bus.h>
45 
46 #include <dev/uart/uart.h>
47 #include <dev/uart/uart_cpu.h>
48 #include <dev/uart/uart_cpu_fdt.h>
49 #include <dev/uart/uart_bus.h>
50 
51 #include "uart_if.h"
52 
53 #define	UART_BDH	0x00	/* Baud Rate Registers: High */
54 #define	UART_BDL	0x01	/* Baud Rate Registers: Low */
55 #define	UART_C1		0x02	/* Control Register 1 */
56 #define	UART_C2		0x03	/* Control Register 2 */
57 #define	UART_S1		0x04	/* Status Register 1 */
58 #define	UART_S2		0x05	/* Status Register 2 */
59 #define	UART_C3		0x06	/* Control Register 3 */
60 #define	UART_D		0x07	/* Data Register */
61 #define	UART_MA1	0x08	/* Match Address Registers 1 */
62 #define	UART_MA2	0x09	/* Match Address Registers 2 */
63 #define	UART_C4		0x0A	/* Control Register 4 */
64 #define	UART_C5		0x0B	/* Control Register 5 */
65 #define	UART_ED		0x0C	/* Extended Data Register */
66 #define	UART_MODEM	0x0D	/* Modem Register */
67 #define	UART_IR		0x0E	/* Infrared Register */
68 #define	UART_PFIFO	0x10	/* FIFO Parameters */
69 #define	UART_CFIFO	0x11	/* FIFO Control Register */
70 #define	UART_SFIFO	0x12	/* FIFO Status Register */
71 #define	UART_TWFIFO	0x13	/* FIFO Transmit Watermark */
72 #define	UART_TCFIFO	0x14	/* FIFO Transmit Count */
73 #define	UART_RWFIFO	0x15	/* FIFO Receive Watermark */
74 #define	UART_RCFIFO	0x16	/* FIFO Receive Count */
75 #define	UART_C7816	0x18	/* 7816 Control Register */
76 #define	UART_IE7816	0x19	/* 7816 Interrupt Enable Register */
77 #define	UART_IS7816	0x1A	/* 7816 Interrupt Status Register */
78 #define	UART_WP7816T0	0x1B	/* 7816 Wait Parameter Register */
79 #define	UART_WP7816T1	0x1B	/* 7816 Wait Parameter Register */
80 #define	UART_WN7816	0x1C	/* 7816 Wait N Register */
81 #define	UART_WF7816	0x1D	/* 7816 Wait FD Register */
82 #define	UART_ET7816	0x1E	/* 7816 Error Threshold Register */
83 #define	UART_TL7816	0x1F	/* 7816 Transmit Length Register */
84 #define	UART_C6		0x21	/* CEA709.1-B Control Register 6 */
85 #define	UART_PCTH	0x22	/* CEA709.1-B Packet Cycle Time Counter High */
86 #define	UART_PCTL	0x23	/* CEA709.1-B Packet Cycle Time Counter Low */
87 #define	UART_B1T	0x24	/* CEA709.1-B Beta1 Timer */
88 #define	UART_SDTH	0x25	/* CEA709.1-B Secondary Delay Timer High */
89 #define	UART_SDTL	0x26	/* CEA709.1-B Secondary Delay Timer Low */
90 #define	UART_PRE	0x27	/* CEA709.1-B Preamble */
91 #define	UART_TPL	0x28	/* CEA709.1-B Transmit Packet Length */
92 #define	UART_IE		0x29	/* CEA709.1-B Interrupt Enable Register */
93 #define	UART_WB		0x2A	/* CEA709.1-B WBASE */
94 #define	UART_S3		0x2B	/* CEA709.1-B Status Register */
95 #define	UART_S4		0x2C	/* CEA709.1-B Status Register */
96 #define	UART_RPL	0x2D	/* CEA709.1-B Received Packet Length */
97 #define	UART_RPREL	0x2E	/* CEA709.1-B Received Preamble Length */
98 #define	UART_CPW	0x2F	/* CEA709.1-B Collision Pulse Width */
99 #define	UART_RIDT	0x30	/* CEA709.1-B Receive Indeterminate Time */
100 #define	UART_TIDT	0x31	/* CEA709.1-B Transmit Indeterminate Time */
101 
102 #define	UART_C2_TE	(1 << 3)	/* Transmitter Enable */
103 #define	UART_C2_TIE	(1 << 7)	/* Transmitter Interrupt Enable */
104 #define	UART_C2_RE	(1 << 2)	/* Receiver Enable */
105 #define	UART_C2_RIE	(1 << 5)	/* Receiver Interrupt Enable */
106 #define	UART_S1_TDRE	(1 << 7)	/* Transmit Data Register Empty Flag */
107 #define	UART_S1_RDRF	(1 << 5)	/* Receive Data Register Full Flag */
108 #define	UART_S2_LBKDIF	(1 << 7)	/* LIN Break Detect Interrupt Flag */
109 
110 #define	UART_C4_BRFA	0x1f	/* Baud Rate Fine Adjust */
111 #define	UART_BDH_SBR	0x1f	/* UART Baud Rate Bits */
112 
113 /*
114  * Low-level UART interface.
115  */
116 static int vf_uart_probe(struct uart_bas *bas);
117 static void vf_uart_init(struct uart_bas *bas, int, int, int, int);
118 static void vf_uart_term(struct uart_bas *bas);
119 static void vf_uart_putc(struct uart_bas *bas, int);
120 static int vf_uart_rxready(struct uart_bas *bas);
121 static int vf_uart_getc(struct uart_bas *bas, struct mtx *);
122 
123 void uart_reinit(struct uart_softc *,int,int);
124 
125 static struct uart_ops uart_vybrid_ops = {
126 	.probe = vf_uart_probe,
127 	.init = vf_uart_init,
128 	.term = vf_uart_term,
129 	.putc = vf_uart_putc,
130 	.rxready = vf_uart_rxready,
131 	.getc = vf_uart_getc,
132 };
133 
134 static int
135 vf_uart_probe(struct uart_bas *bas)
136 {
137 
138 	return (0);
139 }
140 
141 static void
142 vf_uart_init(struct uart_bas *bas, int baudrate, int databits,
143     int stopbits, int parity)
144 {
145 
146 }
147 
148 static void
149 vf_uart_term(struct uart_bas *bas)
150 {
151 
152 }
153 
154 static void
155 vf_uart_putc(struct uart_bas *bas, int c)
156 {
157 
158 	while (!(uart_getreg(bas, UART_S1) & UART_S1_TDRE))
159 		;
160 
161 	uart_setreg(bas, UART_D, c);
162 }
163 
164 static int
165 vf_uart_rxready(struct uart_bas *bas)
166 {
167 	int usr1;
168 
169 	usr1 = uart_getreg(bas, UART_S1);
170 	if (usr1 & UART_S1_RDRF) {
171 		return (1);
172 	}
173 
174 	return (0);
175 }
176 
177 static int
178 vf_uart_getc(struct uart_bas *bas, struct mtx *hwmtx)
179 {
180 	int c;
181 
182 	uart_lock(hwmtx);
183 
184 	while (!(uart_getreg(bas, UART_S1) & UART_S1_RDRF))
185 		;
186 
187 	c = uart_getreg(bas, UART_D);
188 	uart_unlock(hwmtx);
189 
190 	return (c & 0xff);
191 }
192 
193 /*
194  * High-level UART interface.
195  */
196 struct vf_uart_softc {
197 	struct uart_softc base;
198 };
199 
200 void
201 uart_reinit(struct uart_softc *sc, int clkspeed, int baud)
202 {
203 	struct uart_bas *bas;
204 	int sbr;
205 	int brfa;
206 	int reg;
207 
208 	bas = &sc->sc_bas;
209 	if (!bas) {
210 		printf("Error: can't reconfigure bas\n");
211 		return;
212 	}
213 
214 	uart_setreg(bas, UART_MODEM, 0x00);
215 
216 	/*
217 	 * Disable transmitter and receiver
218 	 * for a while.
219 	 */
220 	reg = uart_getreg(bas, UART_C2);
221 	reg &= ~(UART_C2_RE | UART_C2_TE);
222 	uart_setreg(bas, UART_C2, 0x00);
223 
224 	uart_setreg(bas, UART_C1, 0x00);
225 
226 	sbr = (uint16_t) (clkspeed / (baud * 16));
227 	brfa = (clkspeed / baud) - (sbr * 16);
228 
229 	reg = uart_getreg(bas, UART_BDH);
230 	reg &= ~UART_BDH_SBR;
231 	reg |= ((sbr & 0x1f00) >> 8);
232 	uart_setreg(bas, UART_BDH, reg);
233 
234 	reg = sbr & 0x00ff;
235 	uart_setreg(bas, UART_BDL, reg);
236 
237 	reg = uart_getreg(bas, UART_C4);
238 	reg &= ~UART_C4_BRFA;
239 	reg |= (brfa & UART_C4_BRFA);
240 	uart_setreg(bas, UART_C4, reg);
241 
242 	reg = uart_getreg(bas, UART_C2);
243 	reg |= (UART_C2_RE | UART_C2_TE);
244 	uart_setreg(bas, UART_C2, reg);
245 
246 }
247 
248 static int vf_uart_bus_attach(struct uart_softc *);
249 static int vf_uart_bus_detach(struct uart_softc *);
250 static int vf_uart_bus_flush(struct uart_softc *, int);
251 static int vf_uart_bus_getsig(struct uart_softc *);
252 static int vf_uart_bus_ioctl(struct uart_softc *, int, intptr_t);
253 static int vf_uart_bus_ipend(struct uart_softc *);
254 static int vf_uart_bus_param(struct uart_softc *, int, int, int, int);
255 static int vf_uart_bus_probe(struct uart_softc *);
256 static int vf_uart_bus_receive(struct uart_softc *);
257 static int vf_uart_bus_setsig(struct uart_softc *, int);
258 static int vf_uart_bus_transmit(struct uart_softc *);
259 
260 static kobj_method_t vf_uart_methods[] = {
261 	KOBJMETHOD(uart_attach,		vf_uart_bus_attach),
262 	KOBJMETHOD(uart_detach,		vf_uart_bus_detach),
263 	KOBJMETHOD(uart_flush,		vf_uart_bus_flush),
264 	KOBJMETHOD(uart_getsig,		vf_uart_bus_getsig),
265 	KOBJMETHOD(uart_ioctl,		vf_uart_bus_ioctl),
266 	KOBJMETHOD(uart_ipend,		vf_uart_bus_ipend),
267 	KOBJMETHOD(uart_param,		vf_uart_bus_param),
268 	KOBJMETHOD(uart_probe,		vf_uart_bus_probe),
269 	KOBJMETHOD(uart_receive,	vf_uart_bus_receive),
270 	KOBJMETHOD(uart_setsig,		vf_uart_bus_setsig),
271 	KOBJMETHOD(uart_transmit,	vf_uart_bus_transmit),
272 	{ 0, 0 }
273 };
274 
275 static struct uart_class uart_vybrid_class = {
276 	"vybrid",
277 	vf_uart_methods,
278 	sizeof(struct vf_uart_softc),
279 	.uc_ops = &uart_vybrid_ops,
280 	.uc_range = 0x100,
281 	.uc_rclk = 24000000, /* TODO: get value from CCM */
282 	.uc_rshift = 0
283 };
284 
285 static struct ofw_compat_data compat_data[] = {
286 	{"fsl,mvf600-uart",	(uintptr_t)&uart_vybrid_class},
287 	{NULL,			(uintptr_t)NULL},
288 };
289 UART_FDT_CLASS_AND_DEVICE(compat_data);
290 
291 static int
292 vf_uart_bus_attach(struct uart_softc *sc)
293 {
294 	struct uart_bas *bas;
295 	int reg;
296 
297 	bas = &sc->sc_bas;
298 
299 	sc->sc_hwiflow = 0;
300 	sc->sc_hwoflow = 0;
301 
302 	uart_reinit(sc, 66000000, 115200);
303 
304 	reg = uart_getreg(bas, UART_C2);
305 	if (sc->sc_sysdev != NULL && sc->sc_sysdev->type == UART_DEV_CONSOLE) {
306 		reg &= ~UART_C2_RIE;
307 	} else {
308 		reg |= UART_C2_RIE;
309 	}
310 	uart_setreg(bas, UART_C2, reg);
311 
312 	return (0);
313 }
314 
315 static int
316 vf_uart_bus_detach(struct uart_softc *sc)
317 {
318 
319 	/* TODO */
320 	return (0);
321 }
322 
323 static int
324 vf_uart_bus_flush(struct uart_softc *sc, int what)
325 {
326 
327 	/* TODO */
328 	return (0);
329 }
330 
331 static int
332 vf_uart_bus_getsig(struct uart_softc *sc)
333 {
334 
335 	/* TODO */
336 	return (0);
337 }
338 
339 static int
340 vf_uart_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
341 {
342 	int error;
343 
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 
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 	(void)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