te
Copyright (c) 2002, Sun Microsystems, Inc. All Rights Reserved.
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
pci_save_config_regs, pci_restore_config_regs - save and restore the PCI configuration registers

#include <sys/ddi.h>
#include <sys/sunddi.h>



int pci_save_config_regs(dev_info_t *dip);

int pci_restore_config_regs(dev_info_t *dip);

illumos DDI-specific (illumos DDI). dip pci_save_config_regs() saves the current configuration registers on persistent system memory. pci_restore_config_regs() restores configuration registers previously saved by pci_save_config_regs().

pci_save_config_regs() should be called by the driver's power() entry point before powering a device off (to PCI state D3). Likewise, pci_restore_config_regs() should be called after powering a device on (from PCI state D3), but before accessing the device. See power(9E).

pci_save_config_regs() and pci_restore_config_regs() return: DDI_SUCCESS DDI_FAILURE Both these functions can be called from user or kernel context. Example 1 Invoking the save and restore functions

static int
xx_power(dev_info_t *dip, int component, int level) {
 struct xx *xx;
 int rval = DDI_SUCCESS;

 xx = ddi_get_soft_state(xx_softstate, ddi_get_instance(dip));
 if (xx == NULL) {
 return (DDI_FAILURE);
 }

 mutex_enter(&xx->x_mutex);

 switch (level) {
 case PM_LEVEL_D0:
 XX_POWER_ON(xx);
 if (pci_restore_config_regs(dip) == DDI_FAILURE) {
 /*
 * appropriate error path handling here
 */
 ...
 rval = DDI_FAILURE;
 }
 break;

 case PM_LEVEL_D3:
 if (pci_save_config_regs(dip) == DDI_FAILURE) {
 /*
 * appropriate error path handling here
 */
 ...
 rval = DDI_FAILURE;
 }
 else {
 XX_POWER_OFF(xx);
 }
 break;

 default:
 rval = DDI_FAILURE;
 break;
 }

 mutex_exit(&xx->x_mutex);
 return (rval);
}

See attributes(7) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE

Interface Stability Committed

attributes (7), power (9E)

Writing Device Drivers

PCI Bus Power Management Interface Specification Version 1.1

PCI Bus Specification Revision 2.1