1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (C) 2019 Leandro Lupori
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#include <sys/linker_set.h>
29#include <sys/param.h>
30#include <sys/types.h>
31
32struct thread;
33
34#include <vm/vm.h>
35#include <vm/pmap.h>
36
37#include <dev/ofw/openfirm.h>
38#include <gdb/gdb.h>
39
40#include "opal.h"
41
42static gdb_probe_f uart_opal_dbg_probe;
43static gdb_init_f uart_opal_dbg_init;
44static gdb_term_f uart_opal_dbg_term;
45static gdb_getc_f uart_opal_dbg_getc;
46static gdb_putc_f uart_opal_dbg_putc;
47
48GDB_DBGPORT(uart_opal, uart_opal_dbg_probe,
49    uart_opal_dbg_init, uart_opal_dbg_term,
50    uart_opal_dbg_getc, uart_opal_dbg_putc);
51
52static int64_t termnum;
53
54static int
55uart_opal_dbg_probe(void)
56{
57	char buf[64];
58	cell_t reg;
59	phandle_t dev;
60
61	if (!getenv_string("hw.uart.dbgport", buf, sizeof(buf)))
62		return (-1);
63	if ((dev = OF_finddevice(buf)) == -1)
64		return (-1);
65
66	if (OF_getprop(dev, "device_type", buf, sizeof(buf)) == -1)
67		return (-1);
68	if (strcmp(buf, "serial") != 0)
69		return (-1);
70
71	if (OF_getprop(dev, "compatible", buf, sizeof(buf)) == -1)
72		return (-1);
73	if (strcmp(buf, "ibm,opal-console-raw") != 0)
74		return (-1);
75
76	reg = ~0U;
77	OF_getencprop(dev, "reg", &reg, sizeof(reg));
78	if (reg == ~0U)
79		return (-1);
80	termnum = reg;
81
82	return (0);
83}
84
85static void
86uart_opal_dbg_init(void)
87{
88}
89
90static void
91uart_opal_dbg_term(void)
92{
93}
94
95static int
96uart_opal_dbg_getc(void)
97{
98	char c;
99	int err;
100	int64_t len;
101	uint64_t lenp, bufp;
102
103	len = 1;
104	if (pmap_bootstrapped) {
105		lenp = vtophys(&len);
106		bufp = vtophys(&c);
107	} else {
108		lenp = (uint64_t)&len;
109		bufp = (uint64_t)&c;
110	}
111
112	err = opal_call(OPAL_CONSOLE_READ, termnum, lenp, bufp);
113	if (err != OPAL_SUCCESS || len != 1)
114		return (-1);
115
116	opal_call(OPAL_POLL_EVENTS, NULL);
117
118	return (c);
119}
120
121static void
122uart_opal_dbg_putc(int c)
123{
124	char ch;
125	int err;
126	int64_t len;
127	uint64_t lenp, bufp;
128
129	ch = (unsigned char)c;
130	len = 1;
131	if (pmap_bootstrapped) {
132		lenp = vtophys(&len);
133		bufp = vtophys(&ch);
134	} else {
135		lenp = (uint64_t)&len;
136		bufp = (uint64_t)&ch;
137	}
138
139	for (;;) {
140		err = opal_call(OPAL_CONSOLE_WRITE, termnum, lenp, bufp);
141		/* Clear FIFO if needed. */
142		if (err == OPAL_BUSY_EVENT)
143			opal_call(OPAL_POLL_EVENTS, NULL);
144		else
145			/* break on success or unrecoverable errors */
146			break;
147	}
148	DELAY(100);
149}
150