1/*	$NetBSD: apei_bert.c,v 1.1 2024/03/20 17:11:43 riastradh Exp $	*/
2
3/*-
4 * Copyright (c) 2024 The NetBSD Foundation, Inc.
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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29/*
30 * APEI BERT -- Boot Error Record Table
31 *
32 * https://uefi.org/specs/ACPI/6.5/18_Platform_Error_Interfaces.html#boot-error-source
33 */
34
35#include <sys/cdefs.h>
36__KERNEL_RCSID(0, "$NetBSD: apei_bert.c,v 1.1 2024/03/20 17:11:43 riastradh Exp $");
37
38#include <sys/types.h>
39
40#include <sys/systm.h>
41
42#include <dev/acpi/acpivar.h>
43#include <dev/acpi/apeivar.h>
44#include <dev/acpi/apei_bertvar.h>
45
46#define	_COMPONENT	ACPI_RESOURCE_COMPONENT
47ACPI_MODULE_NAME	("apei")
48
49/*
50 * apei_bert_attach(sc)
51 *
52 *	Scan the Boot Error Record Table for hardware errors that
53 *	happened early at boot or on the previous boot.
54 */
55void
56apei_bert_attach(struct apei_softc *sc)
57{
58	const ACPI_TABLE_BERT *bert = sc->sc_tab.bert;
59	struct apei_bert_softc *bsc = &sc->sc_bert;
60	bool fatal = false;
61
62	/*
63	 * Verify the table is large enough.
64	 */
65	if (bert->Header.Length < sizeof(*bert)) {
66		aprint_error_dev(sc->sc_dev, "BERT: truncated table:"
67		    " %"PRIu32" < %zu bytes\n",
68		    bert->Header.Length, sizeof(*bert));
69		return;
70	}
71
72	/*
73	 * In verbose boots, print the BERT physical address and
74	 * length.  The operator might find this handy for dd'ing it
75	 * from /dev/mem, if allowed.
76	 */
77	aprint_verbose_dev(sc->sc_dev, "BERT: 0x%x bytes at 0x%"PRIx64"\n",
78	    bert->RegionLength, bert->Address);
79
80	/*
81	 * Verify the length is enough for a Generic Error Status Block
82	 * header, at least.
83	 */
84	if (bert->RegionLength < sizeof(*bsc->bsc_gesb)) {
85		aprint_error_dev(sc->sc_dev,
86		    "BERT: truncated boot error region, %"PRIu32" < %zu bytes",
87		    bert->RegionLength, sizeof(*bsc->bsc_gesb));
88		return;
89	}
90
91	/*
92	 * Map the GESB and process it, but don't acknowledge it --
93	 * this is a one-time polled source; it won't (or at least,
94	 * shouldn't) change after boot.
95	 */
96	bsc->bsc_gesb = AcpiOsMapMemory(bert->Address, bert->RegionLength);
97	const uint32_t status = apei_gesb_report(sc, bsc->bsc_gesb,
98	    bert->RegionLength, "boot error record", &fatal);
99	if (status == 0) {
100		/*
101		 * If there were no boot errors, leave a note in dmesg
102		 * to this effect without cluttering up the console
103		 * unless you asked for it by `boot -v'.
104		 */
105		aprint_verbose_dev(sc->sc_dev,
106		    "BERT: no boot errors recorded\n");
107	}
108
109	/*
110	 * If the error was fatal, print a warning to the console.
111	 * Probably not actually fatal now since it is usually related
112	 * to early or previous boot.
113	 */
114	if (fatal) {
115		aprint_error_dev(sc->sc_dev, "BERT:"
116		    " fatal pre-boot error recorded\n");
117	}
118
119	/* XXX expose content via sysctl? */
120}
121
122/*
123 * apei_bert_detach(sc)
124 *
125 *	Free any software resources associated with the Boot Error
126 *	Record Table.
127 */
128void
129apei_bert_detach(struct apei_softc *sc)
130{
131	const ACPI_TABLE_BERT *bert = sc->sc_tab.bert;
132	struct apei_bert_softc *bsc = &sc->sc_bert;
133
134	if (bsc->bsc_gesb) {
135		AcpiOsUnmapMemory(bsc->bsc_gesb, bert->RegionLength);
136		bsc->bsc_gesb = NULL;
137	}
138}
139