src/core/device.c

   1 /*
   2  * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * License, or any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17  */
  18
  19 #include <string.h>
  20 #include <gpxe/list.h>
  21 #include <gpxe/tables.h>
  22 #include <gpxe/device.h>
  23 #include <gpxe/init.h>
  24
  25 /**
  26  * @file
  27  *
  28  * Device model
  29  *
  30  */
  31
  32 static struct root_device root_devices[0]
  33         __table_start ( struct root_device, root_devices );
  34 static struct root_device root_devices_end[0]
  35         __table_end ( struct root_device, root_devices );
  36
  37 /** Registered root devices */
  38 static LIST_HEAD ( devices );
  39
  40 /**
  41  * Probe a root device
  42  *
  43  * @v rootdev           Root device
  44  * @ret rc              Return status code
  45  */
  46 static int rootdev_probe ( struct root_device *rootdev ) {
  47         int rc;
  48
  49         DBG ( "Adding %s root bus\n", rootdev->dev.name );
  50         if ( ( rc = rootdev->driver->probe ( rootdev ) ) != 0 ) {
  51                 DBG ( "Failed to add %s root bus: %s\n",
  52                       rootdev->dev.name, strerror ( rc ) );
  53                 return rc;
  54         }
  55
  56         return 0;
  57 }
  58
  59 /**
  60  * Remove a root device
  61  *
  62  * @v rootdev           Root device
  63  */
  64 static void rootdev_remove ( struct root_device *rootdev ) {
  65         rootdev->driver->remove ( rootdev );
  66         DBG ( "Removed %s root bus\n", rootdev->dev.name );
  67 }
  68
  69 /**
  70  * Probe all devices
  71  *
  72  * This initiates probing for all devices in the system.  After this
  73  * call, the device hierarchy will be populated, and all hardware
  74  * should be ready to use.
  75  */
  76 static void probe_devices ( void ) {
  77         struct root_device *rootdev;
  78         int rc;
  79
  80         for ( rootdev = root_devices; rootdev < root_devices_end; rootdev++ ) {
  81                 list_add ( &rootdev->dev.siblings, &devices );
  82                 INIT_LIST_HEAD ( &rootdev->dev.children );
  83                 if ( ( rc = rootdev_probe ( rootdev ) ) != 0 )
  84                         list_del ( &rootdev->dev.siblings );
  85         }
  86 }
  87
  88 /**
  89  * Remove all devices
  90  *
  91  */
  92 static void remove_devices ( int flags ) {
  93         struct root_device *rootdev;
  94         struct root_device *tmp;
  95
  96         if ( flags & SHUTDOWN_KEEP_DEVICES ) {
  97                 DBG ( "Refusing to remove devices on shutdown\n" );
  98                 return;
  99         }
 100
 101         list_for_each_entry_safe ( rootdev, tmp, &devices, dev.siblings ) {
 102                 rootdev_remove ( rootdev );
 103                 list_del ( &rootdev->dev.siblings );
 104         }
 105 }
 106
 107 struct startup_fn startup_devices __startup_fn ( STARTUP_NORMAL ) = {
 108         .startup = probe_devices,
 109         .shutdown = remove_devices,
 110 };