1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (C) 2011 by Nathan Whitehorn. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
19 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
21 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
22 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
23 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
24 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD$");
29
30#include <sys/endian.h>
31#include <sys/param.h>
32#include <sys/kdb.h>
33#include <sys/kernel.h>
34#include <sys/priv.h>
35#include <sys/systm.h>
36#include <sys/module.h>
37#include <sys/types.h>
38#include <sys/conf.h>
39#include <sys/cons.h>
40#include <sys/tty.h>
41#include <machine/bus.h>
42
43#include <dev/ofw/openfirm.h>
44#include <dev/ofw/ofw_bus.h>
45#include <dev/ofw/ofw_bus_subr.h>
46#include <dev/uart/uart.h>
47#include <dev/uart/uart_cpu.h>
48#include <dev/uart/uart_bus.h>
49
50#include "phyp-hvcall.h"
51#include "uart_if.h"
52
53struct uart_phyp_softc {
54	device_t dev;
55	phandle_t node;
56	int vtermid;
57
58	struct tty *tp;
59	struct resource *irqres;
60	int irqrid;
61	struct callout callout;
62	void *sc_icookie;
63	int polltime;
64
65	struct mtx sc_mtx;
66	int protocol;
67
68	union {
69		uint64_t u64[2];
70		char str[16];
71	} phyp_inbuf;
72	uint64_t inbuflen;
73	uint8_t outseqno;
74};
75
76static struct uart_phyp_softc	*console_sc = NULL;
77#if defined(KDB)
78static int			alt_break_state;
79#endif
80
81enum {
82	HVTERM1, HVTERMPROT
83};
84
85#define VS_DATA_PACKET_HEADER		0xff
86#define VS_CONTROL_PACKET_HEADER	0xfe
87#define  VSV_SET_MODEM_CTL		0x01
88#define  VSV_MODEM_CTL_UPDATE		0x02
89#define  VSV_RENEGOTIATE_CONNECTION	0x03
90#define VS_QUERY_PACKET_HEADER		0xfd
91#define  VSV_SEND_VERSION_NUMBER	0x01
92#define  VSV_SEND_MODEM_CTL_STATUS	0x02
93#define VS_QUERY_RESPONSE_PACKET_HEADER	0xfc
94
95static int uart_phyp_probe(device_t dev);
96static int uart_phyp_attach(device_t dev);
97static void uart_phyp_intr(void *v);
98
99static device_method_t uart_phyp_methods[] = {
100	/* Device interface */
101	DEVMETHOD(device_probe,		uart_phyp_probe),
102	DEVMETHOD(device_attach,	uart_phyp_attach),
103
104	DEVMETHOD_END
105};
106
107static driver_t uart_phyp_driver = {
108	"uart",
109	uart_phyp_methods,
110	sizeof(struct uart_phyp_softc),
111};
112
113DRIVER_MODULE(uart_phyp, vdevice, uart_phyp_driver, uart_devclass, 0, 0);
114
115static cn_probe_t uart_phyp_cnprobe;
116static cn_init_t uart_phyp_cninit;
117static cn_term_t uart_phyp_cnterm;
118static cn_getc_t uart_phyp_cngetc;
119static cn_putc_t uart_phyp_cnputc;
120static cn_grab_t uart_phyp_cngrab;
121static cn_ungrab_t uart_phyp_cnungrab;
122
123CONSOLE_DRIVER(uart_phyp);
124
125static void uart_phyp_ttyoutwakeup(struct tty *tp);
126
127static struct ttydevsw uart_phyp_tty_class = {
128	.tsw_flags	= TF_INITLOCK|TF_CALLOUT,
129	.tsw_outwakeup	= uart_phyp_ttyoutwakeup,
130};
131
132static int
133uart_phyp_probe_node(struct uart_phyp_softc *sc)
134{
135	phandle_t node = sc->node;
136	uint32_t reg;
137	char buf[64];
138
139	sc->inbuflen = 0;
140	sc->outseqno = 0;
141
142	if (OF_getprop(node, "name", buf, sizeof(buf)) <= 0)
143		return (ENXIO);
144	if (strcmp(buf, "vty") != 0)
145		return (ENXIO);
146
147	if (OF_getprop(node, "device_type", buf, sizeof(buf)) <= 0)
148		return (ENXIO);
149	if (strcmp(buf, "serial") != 0)
150		return (ENXIO);
151
152	reg = -1;
153	OF_getencprop(node, "reg", &reg, sizeof(reg));
154	if (reg == -1)
155		return (ENXIO);
156	sc->vtermid = reg;
157	sc->node = node;
158
159	if (OF_getprop(node, "compatible", buf, sizeof(buf)) <= 0)
160		return (ENXIO);
161	if (strcmp(buf, "hvterm1") == 0) {
162		sc->protocol = HVTERM1;
163		return (0);
164	} else if (strcmp(buf, "hvterm-protocol") == 0) {
165		sc->protocol = HVTERMPROT;
166		return (0);
167	}
168
169	return (ENXIO);
170}
171
172static int
173uart_phyp_probe(device_t dev)
174{
175	const char *name;
176	struct uart_phyp_softc sc;
177	int err;
178
179	name = ofw_bus_get_name(dev);
180	if (name == NULL || strcmp(name, "vty") != 0)
181		return (ENXIO);
182
183	sc.node = ofw_bus_get_node(dev);
184	err = uart_phyp_probe_node(&sc);
185	if (err != 0)
186		return (err);
187
188	device_set_desc(dev, "POWER Hypervisor Virtual Serial Port");
189
190	return (err);
191}
192
193static void
194uart_phyp_cnprobe(struct consdev *cp)
195{
196	char buf[64];
197	ihandle_t stdout;
198	phandle_t input, chosen;
199	static struct uart_phyp_softc sc;
200
201	if ((chosen = OF_finddevice("/chosen")) == -1)
202		goto fail;
203
204	/* Check if OF has an active stdin/stdout */
205	input = -1;
206	if (OF_getencprop(chosen, "stdout", &stdout,
207	    sizeof(stdout)) == sizeof(stdout) && stdout != 0)
208		input = OF_instance_to_package(stdout);
209	if (input == -1)
210		goto fail;
211
212	if (OF_getprop(input, "device_type", buf, sizeof(buf)) == -1)
213		goto fail;
214	if (strcmp(buf, "serial") != 0)
215		goto fail;
216
217	sc.node = input;
218	if (uart_phyp_probe_node(&sc) != 0)
219		goto fail;
220	mtx_init(&sc.sc_mtx, "uart_phyp", NULL, MTX_SPIN | MTX_QUIET |
221	    MTX_NOWITNESS);
222
223	cp->cn_pri = CN_NORMAL;
224	console_sc = &sc;
225	return;
226
227fail:
228	cp->cn_pri = CN_DEAD;
229	return;
230}
231
232static int
233uart_phyp_attach(device_t dev)
234{
235	struct uart_phyp_softc *sc;
236	int unit;
237
238	sc = device_get_softc(dev);
239	sc->dev = dev;
240	sc->node = ofw_bus_get_node(dev);
241	uart_phyp_probe_node(sc);
242
243	unit = device_get_unit(dev);
244	sc->tp = tty_alloc(&uart_phyp_tty_class, sc);
245	mtx_init(&sc->sc_mtx, device_get_nameunit(dev), NULL,
246	    MTX_SPIN | MTX_QUIET | MTX_NOWITNESS);
247
248	if (console_sc != NULL && console_sc->vtermid == sc->vtermid) {
249		sc->outseqno = console_sc->outseqno;
250		console_sc = sc;
251		sprintf(uart_phyp_consdev.cn_name, "ttyu%r", unit);
252		tty_init_console(sc->tp, 0);
253	}
254
255	sc->irqrid = 0;
256	sc->irqres = bus_alloc_resource_any(dev, SYS_RES_IRQ, &sc->irqrid,
257	    RF_ACTIVE | RF_SHAREABLE);
258	if (sc->irqres != NULL) {
259		bus_setup_intr(dev, sc->irqres, INTR_TYPE_TTY | INTR_MPSAFE,
260		    NULL, uart_phyp_intr, sc, &sc->sc_icookie);
261	} else {
262		callout_init(&sc->callout, 1);
263		sc->polltime = hz / 20;
264		if (sc->polltime < 1)
265			sc->polltime = 1;
266		callout_reset(&sc->callout, sc->polltime, uart_phyp_intr, sc);
267	}
268
269	tty_makedev(sc->tp, NULL, "u%r", unit);
270
271	return (0);
272}
273
274static void
275uart_phyp_cninit(struct consdev *cp)
276{
277
278	strcpy(cp->cn_name, "phypcons");
279}
280
281static void
282uart_phyp_cnterm(struct consdev *cp)
283{
284}
285
286static int
287uart_phyp_get(struct uart_phyp_softc *sc, void *buffer, size_t bufsize)
288{
289	int err;
290	int hdr = 0;
291	uint64_t i, j;
292
293	uart_lock(&sc->sc_mtx);
294	if (sc->inbuflen == 0) {
295		err = phyp_pft_hcall(H_GET_TERM_CHAR, sc->vtermid,
296		    0, 0, 0, &sc->inbuflen, &sc->phyp_inbuf.u64[0],
297		    &sc->phyp_inbuf.u64[1]);
298#if BYTE_ORDER == LITTLE_ENDIAN
299		sc->phyp_inbuf.u64[0] = be64toh(sc->phyp_inbuf.u64[0]);
300		sc->phyp_inbuf.u64[1] = be64toh(sc->phyp_inbuf.u64[1]);
301#endif
302		if (err != H_SUCCESS) {
303			uart_unlock(&sc->sc_mtx);
304			return (-1);
305		}
306		hdr = 1;
307	}
308
309	if (sc->inbuflen == 0) {
310		uart_unlock(&sc->sc_mtx);
311		return (0);
312	}
313
314	if ((sc->protocol == HVTERMPROT) && (hdr == 1)) {
315		sc->inbuflen = sc->inbuflen - 4;
316		/* The VTERM protocol has a 4 byte header, skip it here. */
317		memmove(&sc->phyp_inbuf.str[0], &sc->phyp_inbuf.str[4],
318		    sc->inbuflen);
319	}
320
321	/*
322	 * Since version 2.11.0, QEMU became bug-compatible with
323	 * PowerVM's vty implementation, by inserting a \0 after
324	 * every \r going to the guest. Guests are expected to
325	 * workaround this issue by removing every \0 immediately
326	 * following a \r.
327	 */
328	if (hdr == 1) {
329		for (i = 0, j = 0; i < sc->inbuflen; i++, j++) {
330			if (i > j)
331				sc->phyp_inbuf.str[j] = sc->phyp_inbuf.str[i];
332
333			if (sc->phyp_inbuf.str[i] == '\r' &&
334			    i < sc->inbuflen - 1 &&
335			    sc->phyp_inbuf.str[i + 1] == '\0')
336				i++;
337		}
338		sc->inbuflen -= i - j;
339	}
340
341	if (bufsize > sc->inbuflen)
342		bufsize = sc->inbuflen;
343
344	memcpy(buffer, sc->phyp_inbuf.str, bufsize);
345	sc->inbuflen -= bufsize;
346	if (sc->inbuflen > 0)
347		memmove(&sc->phyp_inbuf.str[0], &sc->phyp_inbuf.str[bufsize],
348		    sc->inbuflen);
349
350	uart_unlock(&sc->sc_mtx);
351	return (bufsize);
352}
353
354static int
355uart_phyp_put(struct uart_phyp_softc *sc, void *buffer, size_t bufsize)
356{
357	uint16_t seqno;
358	uint64_t len = 0;
359	int	err;
360
361	union {
362		uint64_t u64[2];
363		char bytes[16];
364	} cbuf;
365
366	uart_lock(&sc->sc_mtx);
367	switch (sc->protocol) {
368	case HVTERM1:
369		if (bufsize > 16)
370			bufsize = 16;
371		memcpy(&cbuf, buffer, bufsize);
372		len = bufsize;
373		break;
374	case HVTERMPROT:
375		if (bufsize > 12)
376			bufsize = 12;
377		seqno = sc->outseqno++;
378		cbuf.bytes[0] = VS_DATA_PACKET_HEADER;
379		cbuf.bytes[1] = 4 + bufsize; /* total length, max 16 bytes */
380		cbuf.bytes[2] = (seqno >> 8) & 0xff;
381		cbuf.bytes[3] = seqno & 0xff;
382		memcpy(&cbuf.bytes[4], buffer, bufsize);
383		len = 4 + bufsize;
384		break;
385	}
386
387	do {
388	    err = phyp_hcall(H_PUT_TERM_CHAR, sc->vtermid, len, htobe64(cbuf.u64[0]),
389			    htobe64(cbuf.u64[1]));
390		DELAY(100);
391	} while (err == H_BUSY);
392
393	uart_unlock(&sc->sc_mtx);
394
395	return (bufsize);
396}
397
398static int
399uart_phyp_cngetc(struct consdev *cp)
400{
401	unsigned char c;
402	int retval;
403
404	retval = uart_phyp_get(console_sc, &c, 1);
405	if (retval != 1)
406		return (-1);
407#if defined(KDB)
408	kdb_alt_break(c, &alt_break_state);
409#endif
410
411	return (c);
412}
413
414static void
415uart_phyp_cnputc(struct consdev *cp, int c)
416{
417	unsigned char ch = c;
418	uart_phyp_put(console_sc, &ch, 1);
419}
420
421static void
422uart_phyp_cngrab(struct consdev *cp)
423{
424}
425
426static void
427uart_phyp_cnungrab(struct consdev *cp)
428{
429}
430
431static void
432uart_phyp_ttyoutwakeup(struct tty *tp)
433{
434	struct uart_phyp_softc *sc;
435	char buffer[8];
436	int len;
437
438	sc = tty_softc(tp);
439
440	while ((len = ttydisc_getc(tp, buffer, sizeof(buffer))) != 0)
441		uart_phyp_put(sc, buffer, len);
442}
443
444static void
445uart_phyp_intr(void *v)
446{
447	struct uart_phyp_softc *sc = v;
448	struct tty *tp = sc->tp;
449	unsigned char c;
450	int len;
451
452	tty_lock(tp);
453	while ((len = uart_phyp_get(sc, &c, 1)) > 0)
454		ttydisc_rint(tp, c, 0);
455	ttydisc_rint_done(tp);
456	tty_unlock(tp);
457
458	if (sc->irqres == NULL)
459		callout_reset(&sc->callout, sc->polltime, uart_phyp_intr, sc);
460}
461