1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2010 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25 /*
26 * Copyright 2019 Peter Tribble.
27 */
28
29 #include <sys/types.h>
30 #include <sys/param.h>
31 #include <sys/fcntl.h>
32 #include <sys/promif.h>
33 #include <sys/prom_plat.h>
34 #include <sys/salib.h>
35
36 extern int is_sun4v;
37
38 /*
39 * Retain a page or reclaim a previously retained page of physical
40 * memory for use by the prom upgrade. If successful, leave
41 * an indication that a page was retained by creating a boolean
42 * property in the root node.
43 *
44 * XXX: SUNW,retain doesn't work as expected on server systems,
45 * so we don't try to retain any memory on those systems.
46 *
47 * XXX: do a '0 to my-self' as a workaround for 4160914
48 */
49
50 int dont_retain_memory;
51
52 void
retain_nvram_page(void)53 retain_nvram_page(void)
54 {
55 unsigned long long phys = 0;
56 int len;
57 char name[32];
58 static char create_prop[] =
59 "0 to my-self dev / 0 0 \" boot-retained-page\" property";
60 static char ue[] = "SUNW,Ultra-Enterprise";
61 extern int verbosemode;
62
63 if (dont_retain_memory)
64 return;
65
66 if (!is_sun4v) {
67 len = prom_getproplen(prom_rootnode(), "name");
68 if ((len != -1) && (len <= sizeof (name))) {
69 (void) prom_getprop(prom_rootnode(), "name", name);
70 if (strcmp(name, ue) == 0)
71 return;
72 }
73 }
74
75 if (prom_retain("OBPnvram", PAGESIZE, PAGESIZE, &phys) != 0) {
76 printf("prom_retain failed\n");
77 return;
78 }
79 if (verbosemode)
80 printf("retained OBPnvram page at 0x%llx\n", phys);
81
82 prom_interpret(create_prop, 0, 0, 0, 0, 0);
83 }
84