sunos man page for pci_restore_config_regs

pci_save_config_regs(9F)				   Kernel Functions for Drivers 				  pci_save_config_regs(9F)

NAME
       pci_save_config_regs, pci_restore_config_regs - save and restore the PCI configuration registers

SYNOPSIS
       #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);

INTERFACE LEVEL
       Solaris DDI-specific (Solaris DDI).

ARGUMENTS
       dip

	   Pointer to the device's dev_info structure.

DESCRIPTION
       pci_save_config_regs() saves the current configuration registers on persistent system memory. pci_restore_config_regs() restores configura-
       tion 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).

RETURN VALUES
       pci_save_config_regs() and pci_restore_config_regs() return:

       DDI_SUCCESS

	   Operation completed successfully.

       DDI_FAILURE

	   Operation failed to complete successfully.

CONTEXT
       Both these functions can be called from user or kernel context.

EXAMPLES
       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);
       }

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Evolving			   |
       +-----------------------------+-----------------------------+

SEE ALSO
       attributes(5), power(9E)

       Writing Device Drivers

       PCI Bus Power Management Interface Specification Version 1.1

       PCI Bus Specification Revision 2.1

SunOS 5.10							   02 June 2000 					  pci_save_config_regs(9F)