uart_dev_imx.c revision 262649
1/*-
2 * Copyright (c) 2012 The FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by Oleksandr Rybalko under sponsorship
6 * from the FreeBSD Foundation.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
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 AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD: stable/10/sys/dev/uart/uart_dev_imx.c 262649 2014-03-01 04:16:54Z imp $");
32
33#include "opt_ddb.h"
34
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/bus.h>
38#include <sys/conf.h>
39#include <sys/kdb.h>
40#include <machine/bus.h>
41#include <machine/fdt.h>
42
43#include <dev/uart/uart.h>
44#include <dev/uart/uart_cpu.h>
45#include <dev/uart/uart_bus.h>
46
47#include <dev/uart/uart_dev_imx5xx.h>
48
49#include "uart_if.h"
50/*
51 * Low-level UART interface.
52 */
53static int imx_uart_probe(struct uart_bas *bas);
54static void imx_uart_init(struct uart_bas *bas, int, int, int, int);
55static void imx_uart_term(struct uart_bas *bas);
56static void imx_uart_putc(struct uart_bas *bas, int);
57static int imx_uart_rxready(struct uart_bas *bas);
58static int imx_uart_getc(struct uart_bas *bas, struct mtx *);
59
60static struct uart_ops uart_imx_uart_ops = {
61	.probe = imx_uart_probe,
62	.init = imx_uart_init,
63	.term = imx_uart_term,
64	.putc = imx_uart_putc,
65	.rxready = imx_uart_rxready,
66	.getc = imx_uart_getc,
67};
68
69static int
70imx_uart_probe(struct uart_bas *bas)
71{
72
73	return (0);
74}
75
76static void
77imx_uart_init(struct uart_bas *bas, int baudrate, int databits,
78    int stopbits, int parity)
79{
80
81}
82
83static void
84imx_uart_term(struct uart_bas *bas)
85{
86
87}
88
89static void
90imx_uart_putc(struct uart_bas *bas, int c)
91{
92
93	while (!(IS(bas, USR2, TXFE)))
94		;
95	SETREG(bas, REG(UTXD), c);
96}
97
98static int
99imx_uart_rxready(struct uart_bas *bas)
100{
101
102	return ((IS(bas, USR2, RDR)) ? 1 : 0);
103}
104
105static int
106imx_uart_getc(struct uart_bas *bas, struct mtx *hwmtx)
107{
108	int c;
109
110	uart_lock(hwmtx);
111	while (!(IS(bas, USR2, RDR)))
112		;
113
114	c = GETREG(bas, REG(URXD));
115	uart_unlock(hwmtx);
116#if defined(KDB)
117	if (c & FLD(URXD, BRK)) {
118		if (kdb_break())
119			return (0);
120	}
121#endif
122	return (c & 0xff);
123}
124
125/*
126 * High-level UART interface.
127 */
128struct imx_uart_softc {
129	struct uart_softc base;
130};
131
132static int imx_uart_bus_attach(struct uart_softc *);
133static int imx_uart_bus_detach(struct uart_softc *);
134static int imx_uart_bus_flush(struct uart_softc *, int);
135static int imx_uart_bus_getsig(struct uart_softc *);
136static int imx_uart_bus_ioctl(struct uart_softc *, int, intptr_t);
137static int imx_uart_bus_ipend(struct uart_softc *);
138static int imx_uart_bus_param(struct uart_softc *, int, int, int, int);
139static int imx_uart_bus_probe(struct uart_softc *);
140static int imx_uart_bus_receive(struct uart_softc *);
141static int imx_uart_bus_setsig(struct uart_softc *, int);
142static int imx_uart_bus_transmit(struct uart_softc *);
143static void imx_uart_bus_grab(struct uart_softc *);
144static void imx_uart_bus_ungrab(struct uart_softc *);
145
146static kobj_method_t imx_uart_methods[] = {
147	KOBJMETHOD(uart_attach,		imx_uart_bus_attach),
148	KOBJMETHOD(uart_detach,		imx_uart_bus_detach),
149	KOBJMETHOD(uart_flush,		imx_uart_bus_flush),
150	KOBJMETHOD(uart_getsig,		imx_uart_bus_getsig),
151	KOBJMETHOD(uart_ioctl,		imx_uart_bus_ioctl),
152	KOBJMETHOD(uart_ipend,		imx_uart_bus_ipend),
153	KOBJMETHOD(uart_param,		imx_uart_bus_param),
154	KOBJMETHOD(uart_probe,		imx_uart_bus_probe),
155	KOBJMETHOD(uart_receive,	imx_uart_bus_receive),
156	KOBJMETHOD(uart_setsig,		imx_uart_bus_setsig),
157	KOBJMETHOD(uart_transmit,	imx_uart_bus_transmit),
158	KOBJMETHOD(uart_grab,		imx_uart_bus_grab),
159	KOBJMETHOD(uart_ungrab,		imx_uart_bus_ungrab),
160	{ 0, 0 }
161};
162
163struct uart_class uart_imx_class = {
164	"imx",
165	imx_uart_methods,
166	sizeof(struct imx_uart_softc),
167	.uc_ops = &uart_imx_uart_ops,
168	.uc_range = 0x100,
169	.uc_rclk = 24000000 /* TODO: get value from CCM */
170};
171
172#define	SIGCHG(c, i, s, d)				\
173	if (c) {					\
174		i |= (i & s) ? s : s | d;		\
175	} else {					\
176		i = (i & s) ? (i & ~s) | d : i;		\
177	}
178
179static int
180imx_uart_bus_attach(struct uart_softc *sc)
181{
182	struct uart_bas *bas;
183	struct uart_devinfo *di;
184
185	bas = &sc->sc_bas;
186	if (sc->sc_sysdev != NULL) {
187		di = sc->sc_sysdev;
188		imx_uart_init(bas, di->baudrate, di->databits, di->stopbits,
189		    di->parity);
190	} else {
191		imx_uart_init(bas, 115200, 8, 1, 0);
192	}
193
194	(void)imx_uart_bus_getsig(sc);
195
196	ENA(bas, UCR4, DREN);
197	DIS(bas, UCR1, RRDYEN);
198	DIS(bas, UCR1, IDEN);
199	DIS(bas, UCR3, RXDSEN);
200	DIS(bas, UCR2, ATEN);
201	DIS(bas, UCR1, TXMPTYEN);
202	DIS(bas, UCR1, TRDYEN);
203	DIS(bas, UCR4, TCEN);
204	DIS(bas, UCR4, OREN);
205	ENA(bas, UCR4, BKEN);
206	DIS(bas, UCR4, WKEN);
207	DIS(bas, UCR1, ADEN);
208	DIS(bas, UCR3, ACIEN);
209	DIS(bas, UCR2, ESCI);
210	DIS(bas, UCR4, ENIRI);
211	DIS(bas, UCR3, AIRINTEN);
212	DIS(bas, UCR3, AWAKEN);
213	DIS(bas, UCR3, FRAERREN);
214	DIS(bas, UCR3, PARERREN);
215	DIS(bas, UCR1, RTSDEN);
216	DIS(bas, UCR2, RTSEN);
217	DIS(bas, UCR3, DTREN);
218	DIS(bas, UCR3, RI);
219	DIS(bas, UCR3, DCD);
220	DIS(bas, UCR3, DTRDEN);
221
222	/* ACK all interrupts */
223	SETREG(bas, REG(USR1), 0xffff);
224	SETREG(bas, REG(USR2), 0xffff);
225	return (0);
226}
227
228static int
229imx_uart_bus_detach(struct uart_softc *sc)
230{
231
232	SETREG(&sc->sc_bas, REG(UCR4), 0);
233
234	return (0);
235}
236
237static int
238imx_uart_bus_flush(struct uart_softc *sc, int what)
239{
240
241	/* TODO */
242	return (0);
243}
244
245static int
246imx_uart_bus_getsig(struct uart_softc *sc)
247{
248	uint32_t new, old, sig;
249	uint8_t bes;
250
251	do {
252		old = sc->sc_hwsig;
253		sig = old;
254		uart_lock(sc->sc_hwmtx);
255		bes = GETREG(&sc->sc_bas, REG(USR2));
256		uart_unlock(sc->sc_hwmtx);
257		/* XXX: chip can show delta */
258		SIGCHG(bes & FLD(USR2, DCDIN), sig, SER_DCD, SER_DDCD);
259		new = sig & ~SER_MASK_DELTA;
260	} while (!atomic_cmpset_32(&sc->sc_hwsig, old, new));
261
262	return (sig);
263}
264
265static int
266imx_uart_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
267{
268	struct uart_bas *bas;
269	int error;
270
271	bas = &sc->sc_bas;
272	error = 0;
273	uart_lock(sc->sc_hwmtx);
274	switch (request) {
275	case UART_IOCTL_BREAK:
276		/* TODO */
277		break;
278	case UART_IOCTL_BAUD:
279		/* TODO */
280		*(int*)data = 115200;
281		break;
282	default:
283		error = EINVAL;
284		break;
285	}
286	uart_unlock(sc->sc_hwmtx);
287
288	return (error);
289}
290
291static int
292imx_uart_bus_ipend(struct uart_softc *sc)
293{
294	struct uart_bas *bas;
295	int ipend;
296	uint32_t usr1, usr2;
297	uint32_t ucr1, ucr4;
298
299	bas = &sc->sc_bas;
300	ipend = 0;
301
302	uart_lock(sc->sc_hwmtx);
303
304	/* Read pending interrupts */
305	usr1 = GETREG(bas, REG(USR1));
306	usr2 = GETREG(bas, REG(USR2));
307	/* ACK interrupts */
308	SETREG(bas, REG(USR1), usr1);
309	SETREG(bas, REG(USR2), usr2);
310
311	ucr1 = GETREG(bas, REG(UCR1));
312	ucr4 = GETREG(bas, REG(UCR4));
313
314	if ((usr2 & FLD(USR2, TXFE)) && (ucr1 & FLD(UCR1, TXMPTYEN))) {
315		DIS(bas, UCR1, TXMPTYEN);
316		/* Continue TXing */
317		ipend |= SER_INT_TXIDLE;
318	}
319	if ((usr2 & FLD(USR2, RDR)) && (ucr4 & FLD(UCR4, DREN))) {
320		DIS(bas, UCR4, DREN);
321		/* Wow, new char on input */
322		ipend |= SER_INT_RXREADY;
323	}
324	if ((usr2 & FLD(USR2, BRCD)) && (ucr4 & FLD(UCR4, BKEN)))
325		ipend |= SER_INT_BREAK;
326
327	uart_unlock(sc->sc_hwmtx);
328
329	return (ipend);
330}
331
332static int
333imx_uart_bus_param(struct uart_softc *sc, int baudrate, int databits,
334    int stopbits, int parity)
335{
336
337	uart_lock(sc->sc_hwmtx);
338	imx_uart_init(&sc->sc_bas, baudrate, databits, stopbits, parity);
339	uart_unlock(sc->sc_hwmtx);
340	return (0);
341}
342
343static int
344imx_uart_bus_probe(struct uart_softc *sc)
345{
346	int error;
347
348	error = imx_uart_probe(&sc->sc_bas);
349	if (error)
350		return (error);
351
352	sc->sc_rxfifosz = 1;
353	sc->sc_txfifosz = 1;
354
355	device_set_desc(sc->sc_dev, "imx_uart");
356	return (0);
357}
358
359static int
360imx_uart_bus_receive(struct uart_softc *sc)
361{
362	struct uart_bas *bas;
363	int xc, out;
364
365	bas = &sc->sc_bas;
366	uart_lock(sc->sc_hwmtx);
367
368	/* Read while we have anything in FIFO */
369	while (IS(bas, USR2, RDR)) {
370		if (uart_rx_full(sc)) {
371			/* No space left in input buffer */
372			sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
373			break;
374		}
375		out = 0;
376		xc = GETREG(bas, REG(URXD));
377
378		/* We have valid char */
379		if (xc & FLD(URXD, CHARRDY))
380			out = xc & 0x000000ff;
381
382		if (xc & FLD(URXD, FRMERR))
383			out |= UART_STAT_FRAMERR;
384		if (xc & FLD(URXD, PRERR))
385			out |= UART_STAT_PARERR;
386		if (xc & FLD(URXD, OVRRUN))
387			out |= UART_STAT_OVERRUN;
388		if (xc & FLD(URXD, BRK))
389			out |= UART_STAT_BREAK;
390
391		uart_rx_put(sc, out);
392	}
393	/* Reenable Data Ready interrupt */
394	ENA(bas, UCR4, DREN);
395
396	uart_unlock(sc->sc_hwmtx);
397	return (0);
398}
399
400static int
401imx_uart_bus_setsig(struct uart_softc *sc, int sig)
402{
403
404	return (0);
405}
406
407static int
408imx_uart_bus_transmit(struct uart_softc *sc)
409{
410	struct uart_bas *bas = &sc->sc_bas;
411	int i;
412
413	bas = &sc->sc_bas;
414	uart_lock(sc->sc_hwmtx);
415
416	/* Fill TX FIFO */
417	for (i = 0; i < sc->sc_txdatasz; i++) {
418		SETREG(bas, REG(UTXD), sc->sc_txbuf[i] & 0xff);
419	}
420
421	sc->sc_txbusy = 1;
422	/* Call me when ready */
423	ENA(bas, UCR1, TXMPTYEN);
424
425	uart_unlock(sc->sc_hwmtx);
426
427	return (0);
428}
429
430static void
431imx_uart_bus_grab(struct uart_softc *sc)
432{
433	struct uart_bas *bas = &sc->sc_bas;
434
435	bas = &sc->sc_bas;
436	uart_lock(sc->sc_hwmtx);
437	DIS(bas, UCR4, DREN);
438	uart_unlock(sc->sc_hwmtx);
439}
440
441static void
442imx_uart_bus_ungrab(struct uart_softc *sc)
443{
444	struct uart_bas *bas = &sc->sc_bas;
445
446	bas = &sc->sc_bas;
447	uart_lock(sc->sc_hwmtx);
448	ENA(bas, UCR4, DREN);
449	uart_unlock(sc->sc_hwmtx);
450}
451