xref: /netbsd-src/sys/arch/arm/amlogic/meson_uart.c (revision 912cfa1495a89368f5a8d2bccc65e0959dcd414a)
1 /* $NetBSD: meson_uart.c,v 1.1 2019/01/19 20:56:03 jmcneill Exp $ */
2 
3 /*-
4  * Copyright (c) 2013 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Matt Thomas of 3am Software Foundry.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include "opt_console.h"
33 #include "locators.h"
34 
35 #include <sys/cdefs.h>
36 
37 __KERNEL_RCSID(1, "$NetBSD: meson_uart.c,v 1.1 2019/01/19 20:56:03 jmcneill Exp $");
38 
39 #define cn_trap()			\
40 	do {				\
41 		console_debugger();	\
42 		cn_trapped = 1;		\
43 	} while (/* CONSTCOND */ 0)
44 
45 #include <sys/param.h>
46 #include <sys/bus.h>
47 #include <sys/device.h>
48 #include <sys/conf.h>
49 #include <sys/intr.h>
50 #include <sys/systm.h>
51 #include <sys/time.h>
52 #include <sys/termios.h>
53 #include <sys/kauth.h>
54 #include <sys/lwp.h>
55 #include <sys/tty.h>
56 
57 #include <dev/cons.h>
58 
59 #include <dev/fdt/fdtvar.h>
60 
61 #include <arm/amlogic/meson_uart.h>
62 
63 static int	meson_uart_match(device_t, cfdata_t, void *);
64 static void	meson_uart_attach(device_t, device_t, void *);
65 
66 static int	meson_uart_intr(void *);
67 
68 static int	meson_uart_cngetc(dev_t);
69 static void	meson_uart_cnputc(dev_t, int);
70 static void	meson_uart_cnpollc(dev_t, int);
71 
72 static void	meson_uart_start(struct tty *);
73 static int	meson_uart_param(struct tty *, struct termios *);
74 
75 extern struct cfdriver mesonuart_cd;
76 
77 static const char * const compatible[] = {
78 	"amlogic,meson6-uart",
79 	"amlogic,meson8-uart",
80 	"amlogic,meson8b-uart",
81 	"amlogic,meson-gx-uart",
82 	NULL
83 };
84 
85 struct meson_uart_softc {
86 	device_t sc_dev;
87 	bus_space_tag_t	sc_bst;
88 	bus_space_handle_t sc_bsh;
89 	void *sc_ih;
90 
91 	struct tty *sc_tty;
92 
93 	int sc_ospeed;
94 	tcflag_t sc_cflag;
95 
96 	u_char sc_buf[1024];
97 };
98 
99 static int meson_uart_console_phandle = -1;
100 
101 static struct meson_uart_softc meson_uart_cnsc;
102 
103 static struct cnm_state meson_uart_cnm_state;
104 
105 struct consdev meson_uart_consdev = {
106 	.cn_getc = meson_uart_cngetc,
107 	.cn_putc = meson_uart_cnputc,
108 	.cn_pollc = meson_uart_cnpollc,
109 	.cn_dev = NODEV,
110 	.cn_pri = CN_NORMAL,
111 };
112 
113 static dev_type_open(meson_uart_open);
114 static dev_type_open(meson_uart_close);
115 static dev_type_read(meson_uart_read);
116 static dev_type_write(meson_uart_write);
117 static dev_type_ioctl(meson_uart_ioctl);
118 static dev_type_tty(meson_uart_tty);
119 static dev_type_poll(meson_uart_poll);
120 static dev_type_stop(meson_uart_stop);
121 
122 const struct cdevsw mesonuart_cdevsw = {
123 	.d_open = meson_uart_open,
124 	.d_close = meson_uart_close,
125 	.d_read = meson_uart_read,
126 	.d_write = meson_uart_write,
127 	.d_ioctl = meson_uart_ioctl,
128 	.d_stop = meson_uart_stop,
129 	.d_tty = meson_uart_tty,
130 	.d_poll = meson_uart_poll,
131 	.d_mmap = nommap,
132 	.d_kqfilter = ttykqfilter,
133 	.d_discard = nodiscard,
134 	.d_flag = D_TTY
135 };
136 
137 static int meson_uart_cmajor = -1;
138 
139 CFATTACH_DECL_NEW(meson_uart, sizeof(struct meson_uart_softc),
140 	meson_uart_match, meson_uart_attach, NULL, NULL);
141 
142 static int
143 meson_uart_match(device_t parent, cfdata_t cf, void *aux)
144 {
145 	struct fdt_attach_args * const faa = aux;
146 
147 	return of_match_compatible(faa->faa_phandle, compatible);
148 }
149 
150 static void
151 meson_uart_attach(device_t parent, device_t self, void *aux)
152 {
153 	struct meson_uart_softc * const sc = device_private(self);
154 	struct fdt_attach_args * const faa = aux;
155 	const int phandle = faa->faa_phandle;
156 	char intrstr[128];
157 	bus_addr_t addr;
158 	bus_size_t size;
159 	struct tty *tp;
160 	int major, minor, error;
161 	uint32_t misc, control;
162 
163 	if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
164 		aprint_error(": couldn't get registers\n");
165 		return;
166 	}
167 
168 	sc->sc_dev = self;
169 	sc->sc_bst = faa->faa_bst;
170 
171 	error = bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh);
172 	if (error != 0) {
173 		aprint_error(": couldn't map registers\n");
174 		return;
175 	}
176 
177 	if (!fdtbus_intr_str(phandle, 0, intrstr, sizeof(intrstr))) {
178 		aprint_error(": failed to decode interrupt\n");
179 		return;
180 	}
181 
182 	sc->sc_ih = fdtbus_intr_establish(phandle, 0, IPL_SERIAL,
183 	    FDT_INTR_MPSAFE, meson_uart_intr, sc);
184 	if (sc->sc_ih == NULL) {
185 		aprint_error(": failed to establish interrupt on %s\n",
186 		    intrstr);
187 		return;
188 	}
189 
190 	if (meson_uart_cmajor == -1) {
191 		/* allocate a major number */
192 		int bmajor = -1, cmajor = -1;
193 		error = devsw_attach("mesonuart", NULL, &bmajor,
194 		    &mesonuart_cdevsw, &cmajor);
195 		if (error) {
196 			aprint_error(": couldn't allocate major number\n");
197 			return;
198 		}
199 		meson_uart_cmajor = cmajor;
200 	}
201 
202 	major = cdevsw_lookup_major(&mesonuart_cdevsw);
203 	minor = device_unit(self);
204 
205 	tp = sc->sc_tty = tty_alloc();
206 	tp->t_oproc = meson_uart_start;
207 	tp->t_param = meson_uart_param;
208 	tp->t_dev = makedev(major, minor);
209 	tp->t_sc = sc;
210 	tty_attach(tp);
211 
212 	aprint_naive("\n");
213 	if (meson_uart_console_phandle == phandle) {
214 		cn_tab->cn_dev = tp->t_dev;
215 		aprint_normal(": console");
216 	}
217 	aprint_normal("\n");
218 
219 	aprint_normal_dev(self, "interrupting on %s\n", intrstr);
220 
221 	misc = bus_space_read_4(sc->sc_bst, sc->sc_bsh, UART_MISC_REG);
222 	misc &= ~UART_MISC_TX_IRQ_CNT;
223 	misc |= __SHIFTIN(0, UART_MISC_TX_IRQ_CNT);
224 	misc &= ~UART_MISC_RX_IRQ_CNT;
225 	misc |= __SHIFTIN(1, UART_MISC_RX_IRQ_CNT);
226 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, UART_MISC_REG, misc);
227 
228 	control = bus_space_read_4(sc->sc_bst, sc->sc_bsh, UART_CONTROL_REG);
229 	control &= ~UART_CONTROL_TX_INT_EN;
230 	control |= UART_CONTROL_RX_INT_EN;
231 	bus_space_write_4(sc->sc_bst, sc->sc_bsh, UART_CONTROL_REG, control);
232 }
233 
234 static int
235 meson_uart_cngetc(dev_t dev)
236 {
237 	bus_space_tag_t bst = meson_uart_cnsc.sc_bst;
238 	bus_space_handle_t bsh = meson_uart_cnsc.sc_bsh;
239 	uint32_t status;
240 	int s, c;
241 
242 	s = splserial();
243 
244 	status = bus_space_read_4(bst, bsh, UART_STATUS_REG);
245 	if (status & UART_STATUS_RX_EMPTY) {
246 		splx(s);
247 		return -1;
248 	}
249 
250 	c = bus_space_read_4(bst, bsh, UART_RFIFO_REG);
251 #if defined(DDB)
252 	extern int db_active;
253 	if (!db_active)
254 #endif
255 	{
256 		int cn_trapped __unused = 0;
257 		cn_check_magic(dev, c, meson_uart_cnm_state);
258 	}
259 
260 	splx(s);
261 
262 	return c & 0xff;
263 }
264 
265 static void
266 meson_uart_cnputc(dev_t dev, int c)
267 {
268 	bus_space_tag_t bst = meson_uart_cnsc.sc_bst;
269 	bus_space_handle_t bsh = meson_uart_cnsc.sc_bsh;
270 	int s;
271 
272 	s = splserial();
273 
274 	while ((bus_space_read_4(bst, bsh, UART_STATUS_REG) & UART_STATUS_TX_FULL) != 0)
275 		;
276 
277 	bus_space_write_4(bst, bsh, UART_WFIFO_REG, c);
278 
279 	splx(s);
280 }
281 
282 
283 static void
284 meson_uart_cnpollc(dev_t dev, int on)
285 {
286 }
287 
288 static int
289 meson_uart_open(dev_t dev, int flag, int mode, lwp_t *l)
290 {
291 	struct meson_uart_softc *sc =
292 	    device_lookup_private(&mesonuart_cd, minor(dev));
293 	struct tty *tp = sc->sc_tty;
294 
295 	if (kauth_authorize_device_tty(l->l_cred,
296 	    KAUTH_DEVICE_TTY_OPEN, tp) != 0) {
297 		return EBUSY;
298 	}
299 
300 	if ((tp->t_state & TS_ISOPEN) == 0 && tp->t_wopen == 0) {
301 		tp->t_dev = dev;
302 		ttychars(tp);
303 		tp->t_iflag = TTYDEF_IFLAG;
304 		tp->t_oflag = TTYDEF_OFLAG;
305 		tp->t_cflag = TTYDEF_CFLAG;
306 		tp->t_lflag = TTYDEF_LFLAG;
307 		tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
308 		ttsetwater(tp);
309 	}
310 	tp->t_state |= TS_CARR_ON;
311 
312 	return tp->t_linesw->l_open(dev, tp);
313 }
314 
315 static int
316 meson_uart_close(dev_t dev, int flag, int mode, lwp_t *l)
317 {
318 	struct meson_uart_softc *sc =
319 	    device_lookup_private(&mesonuart_cd, minor(dev));
320 	struct tty *tp = sc->sc_tty;
321 
322 	tp->t_linesw->l_close(tp, flag);
323 	ttyclose(tp);
324 
325 	return 0;
326 }
327 
328 static int
329 meson_uart_read(dev_t dev, struct uio *uio, int flag)
330 {
331 	struct meson_uart_softc *sc =
332 	    device_lookup_private(&mesonuart_cd, minor(dev));
333 	struct tty *tp = sc->sc_tty;
334 
335 	return tp->t_linesw->l_read(tp, uio, flag);
336 }
337 
338 static int
339 meson_uart_write(dev_t dev, struct uio *uio, int flag)
340 {
341 	struct meson_uart_softc *sc =
342 	    device_lookup_private(&mesonuart_cd, minor(dev));
343 	struct tty *tp = sc->sc_tty;
344 
345 	return tp->t_linesw->l_write(tp, uio, flag);
346 }
347 
348 static int
349 meson_uart_poll(dev_t dev, int events, lwp_t *l)
350 {
351 	struct meson_uart_softc *sc =
352 	    device_lookup_private(&mesonuart_cd, minor(dev));
353 	struct tty *tp = sc->sc_tty;
354 
355 	return tp->t_linesw->l_poll(tp, events, l);
356 }
357 
358 static int
359 meson_uart_ioctl(dev_t dev, u_long cmd, void *data, int flag, lwp_t *l)
360 {
361 	struct meson_uart_softc *sc =
362 	    device_lookup_private(&mesonuart_cd, minor(dev));
363 	struct tty *tp = sc->sc_tty;
364 	int error;
365 
366 	error = tp->t_linesw->l_ioctl(tp, cmd, data, flag, l);
367 	if (error != EPASSTHROUGH)
368 		return error;
369 
370 	return ttioctl(tp, cmd, data, flag, l);
371 }
372 
373 static struct tty *
374 meson_uart_tty(dev_t dev)
375 {
376 	struct meson_uart_softc *sc =
377 	    device_lookup_private(&mesonuart_cd, minor(dev));
378 
379 	return sc->sc_tty;
380 }
381 
382 static void
383 meson_uart_stop(struct tty *tp, int flag)
384 {
385 }
386 
387 static void
388 meson_uart_start(struct tty *tp)
389 {
390 	struct meson_uart_softc *sc = tp->t_sc;
391 	u_char *p = sc->sc_buf;
392 	int s, brem;
393 
394 	s = spltty();
395 
396 	if (tp->t_state & (TS_TTSTOP | TS_BUSY | TS_TIMEOUT)) {
397 		splx(s);
398 		return;
399 	}
400 	tp->t_state |= TS_BUSY;
401 
402 	splx(s);
403 
404 	for (brem = q_to_b(&tp->t_outq, sc->sc_buf, sizeof(sc->sc_buf));
405 	     brem > 0;
406 	     brem--, p++) {
407 		while ((bus_space_read_4(sc->sc_bst, sc->sc_bsh,
408 		    UART_STATUS_REG) & UART_STATUS_TX_FULL) != 0)
409 			;
410 
411 		bus_space_write_4(sc->sc_bst, sc->sc_bsh,
412 		    UART_WFIFO_REG, *p);
413 	}
414 
415 	s = spltty();
416 	tp->t_state &= ~TS_BUSY;
417 	if (ttypull(tp)) {
418 		tp->t_state |= TS_TIMEOUT;
419 		callout_schedule(&tp->t_rstrt_ch, 1);
420 	}
421 	splx(s);
422 }
423 
424 static int
425 meson_uart_param(struct tty *tp, struct termios *t)
426 {
427 
428 	tp->t_ispeed = t->c_ispeed;
429 	tp->t_ospeed = t->c_ospeed;
430 	tp->t_cflag = t->c_cflag;
431 
432 	return 0;
433 }
434 
435 static int
436 meson_uart_intr(void *priv)
437 {
438 	struct meson_uart_softc *sc = priv;
439 	struct tty *tp = sc->sc_tty;
440 	uint32_t status, c;
441 
442 	for (;;) {
443 		int cn_trapped = 0;
444 		status = bus_space_read_4(sc->sc_bst, sc->sc_bsh,
445 		    UART_STATUS_REG);
446 		if (status & UART_STATUS_RX_EMPTY) {
447 			break;
448 		}
449 		if (status & UART_STATUS_BREAK) {
450 			cn_check_magic(tp->t_dev, CNC_BREAK,
451 			    meson_uart_cnm_state);
452 			if (cn_trapped)
453 				continue;
454 		}
455 
456 		c = bus_space_read_4(sc->sc_bst, sc->sc_bsh, UART_RFIFO_REG);
457 		cn_check_magic(tp->t_dev, c & 0xff, meson_uart_cnm_state);
458 		if (cn_trapped)
459 			continue;
460 		tp->t_linesw->l_rint(c & 0xff, tp);
461 	}
462 
463 	return 0;
464 }
465 
466 static int
467 meson_uart_console_match(int phandle)
468 {
469 	return of_match_compatible(phandle, compatible);
470 }
471 
472 static void
473 meson_uart_console_consinit(struct fdt_attach_args *faa, u_int uart_freq)
474 {
475 	struct meson_uart_softc *sc = &meson_uart_cnsc;
476 	const int phandle = faa->faa_phandle;
477 	bus_addr_t addr;
478 	bus_size_t size;
479 	int error;
480 
481 	fdtbus_get_reg(phandle, 0, &addr, &size);
482 
483 	sc->sc_bst = faa->faa_bst;
484 	sc->sc_ospeed = fdtbus_get_stdout_speed();
485 	if (sc->sc_ospeed < 0)
486 		sc->sc_ospeed = 115200;
487 	sc->sc_cflag = fdtbus_get_stdout_flags();
488 
489 	error = bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh);
490 	if (error != 0)
491 		panic("failed to map console, error = %d", error);
492 
493 	cn_tab = &meson_uart_consdev;
494 	cn_init_magic(&meson_uart_cnm_state);
495 	cn_set_magic("\047\001");
496 
497 	meson_uart_console_phandle = phandle;
498 }
499 
500 static const struct fdt_console meson_uart_console = {
501 	.match = meson_uart_console_match,
502 	.consinit = meson_uart_console_consinit,
503 };
504 
505 FDT_CONSOLE(meson_uart, &meson_uart_console);
506