xref: /freebsd/sys/arm/freescale/vybrid/vf_uart.c (revision 1d386b48a555f61cb7325543adbbb5c3f3407a66)
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 #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: can't 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 	.uc_rshift = 0
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 	int error;
341 
342 	error = 0;
343 	uart_lock(sc->sc_hwmtx);
344 	switch (request) {
345 	case UART_IOCTL_BREAK:
346 	/* TODO */
347 		break;
348 	case UART_IOCTL_BAUD:
349 	/* TODO */
350 		*(int*)data = 115200;
351 		break;
352 	default:
353 		error = EINVAL;
354 		break;
355 	}
356 	uart_unlock(sc->sc_hwmtx);
357 
358 	return (error);
359 }
360 
361 static int
362 vf_uart_bus_ipend(struct uart_softc *sc)
363 {
364 	struct uart_bas *bas;
365 	int ipend;
366 	uint32_t usr1, usr2;
367 	int reg;
368 
369 	bas = &sc->sc_bas;
370 	ipend = 0;
371 
372 	uart_lock(sc->sc_hwmtx);
373 
374 	usr1 = uart_getreg(bas, UART_S1);
375 	usr2 = uart_getreg(bas, UART_S2);
376 	(void)uart_getreg(bas, UART_SFIFO);
377 
378 	/* ack usr2 */
379 	uart_setreg(bas, UART_S2, usr2);
380 
381 	if (usr1 & UART_S1_TDRE) {
382 		reg = uart_getreg(bas, UART_C2);
383 		reg &= ~(UART_C2_TIE);
384 		uart_setreg(bas, UART_C2, reg);
385 
386 		if (sc->sc_txbusy != 0) {
387 			ipend |= SER_INT_TXIDLE;
388 		}
389 	}
390 
391 	if (usr1 & UART_S1_RDRF) {
392 		reg = uart_getreg(bas, UART_C2);
393 		reg &= ~(UART_C2_RIE);
394 		uart_setreg(bas, UART_C2, reg);
395 
396 		ipend |= SER_INT_RXREADY;
397 	}
398 
399 	if (usr2 & UART_S2_LBKDIF) {
400 		ipend |= SER_INT_BREAK;
401 	}
402 
403 	uart_unlock(sc->sc_hwmtx);
404 
405 	return (ipend);
406 }
407 
408 static int
409 vf_uart_bus_param(struct uart_softc *sc, int baudrate, int databits,
410     int stopbits, int parity)
411 {
412 
413 	uart_lock(sc->sc_hwmtx);
414 	vf_uart_init(&sc->sc_bas, baudrate, databits, stopbits, parity);
415 	uart_unlock(sc->sc_hwmtx);
416 
417 	return (0);
418 }
419 
420 static int
421 vf_uart_bus_probe(struct uart_softc *sc)
422 {
423 	int error;
424 
425 	error = vf_uart_probe(&sc->sc_bas);
426 	if (error)
427 		return (error);
428 
429 	sc->sc_rxfifosz = 1;
430 	sc->sc_txfifosz = 1;
431 
432 	device_set_desc(sc->sc_dev, "Vybrid Family UART");
433 	return (0);
434 }
435 
436 static int
437 vf_uart_bus_receive(struct uart_softc *sc)
438 {
439 	struct uart_bas *bas;
440 	int reg;
441 	int c;
442 
443 	bas = &sc->sc_bas;
444 	uart_lock(sc->sc_hwmtx);
445 
446 	/* Read FIFO */
447 	while (uart_getreg(bas, UART_S1) & UART_S1_RDRF) {
448 		if (uart_rx_full(sc)) {
449 		/* No space left in input buffer */
450 			sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
451 			break;
452 		}
453 
454 		c = uart_getreg(bas, UART_D);
455 		uart_rx_put(sc, c);
456 	}
457 
458 	/* Reenable Data Ready interrupt */
459 	reg = uart_getreg(bas, UART_C2);
460 	reg |= (UART_C2_RIE);
461 	uart_setreg(bas, UART_C2, reg);
462 
463 	uart_unlock(sc->sc_hwmtx);
464 	return (0);
465 }
466 
467 static int
468 vf_uart_bus_setsig(struct uart_softc *sc, int sig)
469 {
470 	struct uart_bas *bas;
471 	int reg;
472 
473 	/* TODO: implement (?) */
474 
475 	/* XXX workaround to have working console on mount prompt */
476 	/* Enable RX interrupt */
477 	bas = &sc->sc_bas;
478 	if (sc->sc_sysdev != NULL && sc->sc_sysdev->type == UART_DEV_CONSOLE) {
479 		reg = uart_getreg(bas, UART_C2);
480 		reg |= (UART_C2_RIE);
481 		uart_setreg(bas, UART_C2, reg);
482 	}
483 
484 	return (0);
485 }
486 
487 static int
488 vf_uart_bus_transmit(struct uart_softc *sc)
489 {
490 	struct uart_bas *bas = &sc->sc_bas;
491 	int i;
492 	int reg;
493 
494 	bas = &sc->sc_bas;
495 	uart_lock(sc->sc_hwmtx);
496 
497 	/* Fill TX FIFO */
498 	for (i = 0; i < sc->sc_txdatasz; i++) {
499 		uart_setreg(bas, UART_D, sc->sc_txbuf[i] & 0xff);
500 		uart_barrier(&sc->sc_bas);
501 	}
502 
503 	sc->sc_txbusy = 1;
504 
505 	/* Call me when ready */
506 	reg = uart_getreg(bas, UART_C2);
507 	reg |= (UART_C2_TIE);
508 	uart_setreg(bas, UART_C2, reg);
509 
510 	uart_unlock(sc->sc_hwmtx);
511 
512 	return (0);
513 }
514