arch/x86/kernel/promif/prom_env.c

   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 /*
  23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #include <sys/promif.h>
  30 #include <sys/promimpl.h>
  31
  32 /*
  33  * This function is installed for both pre and post output during cpr to keep
  34  * the early stages of the resuming kernel from accessing outside the nucleus
  35  * mapping; we assert that the console is all powered up before it is installed
  36  */
  37 static void
  38 null_outfunc(void)
  39 {
  40 }
  41
  42 static promif_owrap_t nullwrapper =
  43 {
  44         null_outfunc,
  45         null_outfunc
  46 };
  47
  48 static promif_owrap_t *wrapper = &nullwrapper;
  49 static promif_owrap_t pmwrapper;
  50 static promif_owrap_t *saved_wrapper;
  51
  52 promif_owrap_t
  53 *promif_preout(void)
  54 {
  55         promif_owrap_t *ow = wrapper;
  56         (ow->preout)();
  57         return (ow);
  58 }
  59
  60 void
  61 promif_postout(promif_owrap_t *ow)
  62 {
  63         (ow->postout)();
  64 }
  65
  66 void
  67 prom_set_outfuncs(void (*pref)(void), void (*postf)(void))
  68 {
  69         pmwrapper.preout = pref;
  70         pmwrapper.postout = postf;
  71         wrapper = &pmwrapper;
  72 }
  73
  74 void
  75 prom_suspend_prepost(void)
  76 {
  77         saved_wrapper = wrapper;
  78         wrapper = &nullwrapper;
  79 }
  80
  81 void
  82 prom_resume_prepost(void)
  83 {
  84         wrapper = saved_wrapper;
  85         saved_wrapper = NULL;
  86 }