xref: /netbsd-src/sys/arch/arm/nvidia/tegra_cec.c (revision 63aea4bd5b445e491ff0389fe27ec78b3099dba3)
1 /* $NetBSD: tegra_cec.c,v 1.2 2015/12/13 17:39:19 jmcneill Exp $ */
2 
3 /*-
4  * Copyright (c) 2015 Jared D. McNeill <jmcneill@invisible.ca>
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 ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * 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 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: tegra_cec.c,v 1.2 2015/12/13 17:39:19 jmcneill Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/device.h>
35 #include <sys/intr.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/mutex.h>
39 #include <sys/condvar.h>
40 #include <sys/poll.h>
41 #include <sys/select.h>
42 
43 #include <dev/hdmicec/hdmicecio.h>
44 #include <dev/hdmicec/hdmicec_if.h>
45 
46 #include <arm/nvidia/tegra_var.h>
47 #include <arm/nvidia/tegra_pmcreg.h>
48 #include <arm/nvidia/tegra_cecreg.h>
49 
50 #include <dev/fdt/fdtvar.h>
51 
52 #define CEC_VENDORID_NVIDIA	0x00044b
53 
54 static int	tegra_cec_match(device_t, cfdata_t, void *);
55 static void	tegra_cec_attach(device_t, device_t, void *);
56 
57 static int	tegra_cec_intr(void *);
58 
59 struct tegra_cec_softc {
60 	device_t		sc_dev;
61 	bus_space_tag_t		sc_bst;
62 	bus_space_handle_t	sc_bsh;
63 	void			*sc_ih;
64 
65 	kmutex_t		sc_lock;
66 	kcondvar_t		sc_cv;
67 
68 	const char		*sc_hdmidevname;
69 	device_t		sc_cecdev;
70 
71 	struct selinfo		sc_selinfo;
72 
73 	uint8_t			sc_rxbuf[16];
74 	int			sc_rxlen;
75 	bool			sc_rxdone;
76 
77 	uint8_t			sc_txbuf[16];
78 	int			sc_txlen;
79 	int			sc_txcur;
80 	int			sc_txerr;
81 	bool			sc_txdone;
82 };
83 
84 static void	tegra_cec_reset(struct tegra_cec_softc *);
85 
86 static int	tegra_cec_open(void *, int);
87 static void	tegra_cec_close(void *);
88 static int	tegra_cec_ioctl(void *, u_long, void *, int, lwp_t *);
89 static int	tegra_cec_send(void *, const uint8_t *, size_t);
90 static ssize_t	tegra_cec_recv(void *, uint8_t *, size_t);
91 static int	tegra_cec_poll(void *, int, lwp_t *);
92 
93 static const struct hdmicec_hw_if tegra_cec_hw_if = {
94 	.open = tegra_cec_open,
95 	.close = tegra_cec_close,
96 	.ioctl = tegra_cec_ioctl,
97 	.send = tegra_cec_send,
98 	.recv = tegra_cec_recv,
99 	.poll = tegra_cec_poll,
100 };
101 
102 CFATTACH_DECL_NEW(tegra_cec, sizeof(struct tegra_cec_softc),
103 	tegra_cec_match, tegra_cec_attach, NULL, NULL);
104 
105 #define CEC_READ(sc, reg)			\
106     bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg))
107 #define CEC_WRITE(sc, reg, val)			\
108     bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val))
109 #define CEC_SET_CLEAR(sc, reg, set, clr)	\
110     tegra_reg_set_clear((sc)->sc_bst, (sc)->sc_bsh, (reg), (set), (clr))
111 
112 static int
113 tegra_cec_match(device_t parent, cfdata_t cf, void *aux)
114 {
115 	const char * const compatible[] = { "nvidia,tegra124-cec", NULL };
116 	struct fdt_attach_args * const faa = aux;
117 
118 	return of_match_compatible(faa->faa_phandle, compatible);
119 }
120 
121 static void
122 tegra_cec_attach(device_t parent, device_t self, void *aux)
123 {
124 	struct tegra_cec_softc * const sc = device_private(self);
125 	struct fdt_attach_args * const faa = aux;
126 	prop_dictionary_t prop = device_properties(self);
127 	struct hdmicec_attach_args caa;
128 	char intrstr[128];
129 	bus_addr_t addr;
130 	bus_size_t size;
131 	int error;
132 
133 	if (fdtbus_get_reg(faa->faa_phandle, 0, &addr, &size) != 0) {
134 		aprint_error(": couldn't get registers\n");
135 		return;
136 	}
137 
138 	sc->sc_dev = self;
139 	sc->sc_bst = faa->faa_bst;
140 	error = bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh);
141 	if (error) {
142 		aprint_error(": couldn't map %#llx: %d", (uint64_t)addr, error);
143 		return;
144 	}
145 	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_VM);
146 	cv_init(&sc->sc_cv, "tegracec");
147 	selinit(&sc->sc_selinfo);
148 
149 	aprint_naive("\n");
150 	aprint_normal(": HDMI CEC\n");
151 
152 	if (!fdtbus_intr_str(faa->faa_phandle, 0, intrstr, sizeof(intrstr))) {
153 		aprint_error_dev(self, "failed to decode interrupt\n");
154 		return;
155 	}
156 
157 	sc->sc_ih = fdtbus_intr_establish(faa->faa_phandle, 0, IPL_VM,
158 	    FDT_INTR_MPSAFE, tegra_cec_intr, sc);
159 	if (sc->sc_ih == NULL) {
160 		aprint_error_dev(self, "couldn't establish interrupt on %s\n",
161 		    intrstr);
162 		return;
163 	}
164 	aprint_normal_dev(self, "interrupting on %s\n", intrstr);
165 
166 	prop_dictionary_get_cstring_nocopy(prop, "hdmi-device",
167 	    &sc->sc_hdmidevname);
168 
169 	tegra_car_periph_cec_enable();
170 
171 	CEC_WRITE(sc, CEC_SW_CONTROL_REG, 0);
172 	CEC_WRITE(sc, CEC_INPUT_FILTER_REG, 0);
173 	CEC_WRITE(sc, CEC_HW_CONTROL_REG, 0);
174 	CEC_WRITE(sc, CEC_INT_MASK_REG, 0);
175 	CEC_WRITE(sc, CEC_INT_STAT_REG, 0xffffffff);
176 
177 	memset(&caa, 0, sizeof(caa));
178 	caa.priv = sc;
179 	caa.hwif = &tegra_cec_hw_if;
180 	sc->sc_cecdev = config_found(self, &caa, NULL);
181 }
182 
183 static int
184 tegra_cec_intr(void *priv)
185 {
186 	struct tegra_cec_softc * const sc = priv;
187 	uint32_t val;
188 	int handled = 0;
189 
190 	mutex_enter(&sc->sc_lock);
191 	const uint32_t int_stat = CEC_READ(sc, CEC_INT_STAT_REG);
192 
193 	if (int_stat & CEC_INT_RX_REGISTER_FULL) {
194 		val = CEC_READ(sc, CEC_RX_REGISTER_REG);
195 		sc->sc_rxbuf[sc->sc_rxlen++] =
196 		    __SHIFTOUT(val, CEC_RX_REGISTER_DATA);
197 		if ((val & CEC_RX_REGISTER_EOM) != 0 ||
198 		    sc->sc_rxlen == 16) {
199 			CEC_SET_CLEAR(sc, CEC_INT_MASK_REG, 0,
200 			    CEC_INT_RX_REGISTER_FULL);
201 			sc->sc_rxdone = true;
202 			cv_broadcast(&sc->sc_cv);
203 			selnotify(&sc->sc_selinfo, POLLIN|POLLRDNORM,
204 			    NOTE_SUBMIT);
205 		}
206 		CEC_WRITE(sc, CEC_INT_STAT_REG, CEC_INT_RX_REGISTER_FULL);
207 		++handled;
208 	}
209 
210 	if (int_stat & CEC_INT_TX_REGISTER_EMPTY) {
211 		if (sc->sc_txcur < sc->sc_txlen) {
212 			const uint8_t destination = sc->sc_txbuf[0] & 0xf;
213 			val = __SHIFTIN(sc->sc_txbuf[sc->sc_txcur],
214 			    CEC_TX_REGISTER_DATA);
215 			if (sc->sc_txcur == 0)
216 				val |= CEC_TX_REGISTER_GENERATE_START_BIT;
217 			if (sc->sc_txcur == sc->sc_txlen - 1)
218 				val |= CEC_TX_REGISTER_EOM;
219 			if (destination == 0xf)
220 				val |= CEC_TX_REGISTER_ADDRESS_MODE;
221 
222 			CEC_WRITE(sc, CEC_TX_REGISTER_REG, val);
223 			CEC_WRITE(sc, CEC_INT_STAT_REG,
224 			    CEC_INT_TX_REGISTER_EMPTY);
225 			++sc->sc_txcur;
226 		} else {
227 			CEC_SET_CLEAR(sc, CEC_INT_MASK_REG, 0,
228 			    CEC_INT_TX_REGISTER_EMPTY);
229 		}
230 		++handled;
231 	}
232 
233 	if (int_stat & CEC_INT_TX_FRAME_TRANSMITTED) {
234 		CEC_SET_CLEAR(sc, CEC_INT_MASK_REG, 0,
235 		    CEC_INT_TX_FRAME_TRANSMITTED |
236 		    CEC_INT_TX_FRAME_OR_BLOCK_NAKD);
237 		CEC_WRITE(sc, CEC_INT_STAT_REG, CEC_INT_TX_FRAME_TRANSMITTED);
238 		if (int_stat & CEC_INT_TX_FRAME_OR_BLOCK_NAKD) {
239 			CEC_WRITE(sc, CEC_INT_STAT_REG,
240 			    CEC_INT_TX_FRAME_OR_BLOCK_NAKD);
241 			sc->sc_txerr = ECONNREFUSED;
242 			tegra_cec_reset(sc);
243 		}
244 		sc->sc_txdone = true;
245 		cv_broadcast(&sc->sc_cv);
246 		++handled;
247 	}
248 
249 	if (int_stat & CEC_INT_TX_REGISTER_UNDERRUN) {
250 		tegra_cec_reset(sc);
251 		cv_broadcast(&sc->sc_cv);
252 		++handled;
253 	}
254 
255 	mutex_exit(&sc->sc_lock);
256 
257 	return handled;
258 }
259 
260 static void
261 tegra_cec_reset(struct tegra_cec_softc *sc)
262 {
263 	uint32_t val;
264 
265 	KASSERT(mutex_owned(&sc->sc_lock));
266 
267 	val = CEC_READ(sc, CEC_HW_CONTROL_REG);
268 	CEC_WRITE(sc, CEC_HW_CONTROL_REG, 0);
269 	CEC_WRITE(sc, CEC_INT_STAT_REG, 0xffffffff);
270 	CEC_WRITE(sc, CEC_HW_CONTROL_REG, val);
271 }
272 
273 static int
274 tegra_cec_open(void *priv, int flag)
275 {
276 	struct tegra_cec_softc * const sc = priv;
277 
278 	mutex_enter(&sc->sc_lock);
279 	sc->sc_rxlen = 0;
280 	sc->sc_rxdone = false;
281 	CEC_WRITE(sc, CEC_INT_MASK_REG, CEC_INT_RX_REGISTER_FULL);
282 	CEC_WRITE(sc, CEC_HW_CONTROL_REG, CEC_HW_CONTROL_TX_RX_MODE);
283 	mutex_exit(&sc->sc_lock);
284 
285 	return 0;
286 }
287 
288 static void
289 tegra_cec_close(void *priv)
290 {
291 	struct tegra_cec_softc * const sc = priv;
292 
293 	mutex_enter(&sc->sc_lock);
294 	CEC_WRITE(sc, CEC_HW_CONTROL_REG, 0);
295 	CEC_WRITE(sc, CEC_INT_MASK_REG, 0);
296 	CEC_WRITE(sc, CEC_INT_STAT_REG, 0xffffffff);
297 	mutex_exit(&sc->sc_lock);
298 }
299 
300 static int
301 tegra_cec_get_phys_addr(struct tegra_cec_softc *sc, uint16_t *phys_addr)
302 {
303 	device_t hdmidev;
304 
305 	if (sc->sc_hdmidevname == NULL)
306 		return EIO;
307 	hdmidev = device_find_by_xname(sc->sc_hdmidevname);
308 	if (hdmidev == NULL)
309 		return ENXIO;
310 
311 	const prop_dictionary_t prop = device_properties(hdmidev);
312 	if (!prop_dictionary_get_uint16(prop, "physical-address", phys_addr))
313 		return ENOTCONN;
314 
315 	return 0;
316 }
317 
318 static int
319 tegra_cec_ioctl(void *priv, u_long cmd, void *data, int flag, lwp_t *l)
320 {
321 	struct tegra_cec_softc * const sc = priv;
322 	uint32_t val;
323 
324 	switch (cmd) {
325 	case CEC_GET_PHYS_ADDR:
326 		return tegra_cec_get_phys_addr(sc, data);
327 	case CEC_GET_LOG_ADDRS:
328 		val = CEC_READ(sc, CEC_HW_CONTROL_REG);
329 		*(uint16_t *)data =
330 		    __SHIFTOUT(val, CEC_HW_CONTROL_RX_LOGICAL_ADDRS);
331 		return 0;
332 	case CEC_SET_LOG_ADDRS:
333 		val = *(uint16_t *)data & 0x7fff;
334 		CEC_SET_CLEAR(sc, CEC_HW_CONTROL_REG,
335 		    __SHIFTIN(val, CEC_HW_CONTROL_RX_LOGICAL_ADDRS),
336 		    CEC_HW_CONTROL_RX_LOGICAL_ADDRS);
337 		return 0;
338 	case CEC_GET_VENDOR_ID:
339 		*(uint32_t *)data = CEC_VENDORID_NVIDIA;
340 		return 0;
341 	default:
342 		return EINVAL;
343 	}
344 }
345 
346 static int
347 tegra_cec_send(void *priv, const uint8_t *data, size_t len)
348 {
349 	struct tegra_cec_softc * const sc = priv;
350 	int error = 0;
351 
352 	mutex_enter(&sc->sc_lock);
353 
354 	sc->sc_txdone = false;
355 	sc->sc_txcur = 0;
356 	sc->sc_txerr = 0;
357 	memcpy(sc->sc_txbuf, data, len);
358 	sc->sc_txlen = len;
359 
360 	CEC_SET_CLEAR(sc, CEC_INT_MASK_REG,
361 	    CEC_INT_TX_REGISTER_EMPTY |
362 	    CEC_INT_TX_FRAME_TRANSMITTED |
363 	    CEC_INT_TX_FRAME_OR_BLOCK_NAKD, 0);
364 
365 	while (sc->sc_txdone == false) {
366 		error = cv_timedwait_sig(&sc->sc_cv, &sc->sc_lock, hz);
367 		if (error)
368 			break;
369 	}
370 
371 	if (sc->sc_txdone)
372 		error = sc->sc_txerr;
373 
374 	mutex_exit(&sc->sc_lock);
375 
376 	return error;
377 }
378 
379 static ssize_t
380 tegra_cec_recv(void *priv, uint8_t *data, size_t len)
381 {
382 	struct tegra_cec_softc * const sc = priv;
383 	ssize_t alen = -1;
384 	int error = 0;
385 
386 	mutex_enter(&sc->sc_lock);
387 
388 	while (sc->sc_rxdone == false) {
389 		error = cv_timedwait_sig(&sc->sc_cv, &sc->sc_lock, hz);
390 		if (error)
391 			break;
392 	}
393 
394 	if (sc->sc_rxdone) {
395 		memcpy(data, sc->sc_rxbuf, sc->sc_rxlen);
396 		alen = sc->sc_rxlen;
397 		sc->sc_rxlen = 0;
398 		sc->sc_rxdone = false;
399 	}
400 
401 	mutex_exit(&sc->sc_lock);
402 
403 	return alen;
404 }
405 
406 static int
407 tegra_cec_poll(void *priv, int events, lwp_t *l)
408 {
409 	struct tegra_cec_softc * const sc = priv;
410 	int revents;
411 
412 	revents = events & (POLLOUT | POLLWRNORM);
413 
414 	if ((events & (POLLIN | POLLRDNORM)) == 0)
415 		return revents;
416 
417 	mutex_enter(&sc->sc_lock);
418 	if (sc->sc_rxdone) {
419 		revents = (events & (POLLIN | POLLRDNORM));
420 	} else {
421 		selrecord(l, &sc->sc_selinfo);
422 		revents = 0;
423 	}
424 	mutex_exit(&sc->sc_lock);
425 
426 	return revents;
427 }
428