Manual Pages for UNIX Operating System command usage for man pci_report_pmcap

Kernel Functions for Drivers                 pci_report_pmcap(9F)



NAME
     pci_report_pmcap - Report Power Management capability  of  a
     PCI device

SYNOPSIS
     #include 
     #include 



     int pci_report_pmcap(dev_info_t *dip,  int cap, void *arg);


INTERFACE LEVEL
     Solaris DDI specific (Solaris DDI)

PARAMETERS
     dip    Pointer to the device's dev_info structure


     cap    Power management capability


     arg    Argument for the capability


DESCRIPTION
     Some PCI devices provide power  management  capabilities  in
     addition  to  those  provided  by  the  PCI Power Management
     Specification. The pci_report_pmcap() function reports those
     Power  Management  capabilities  of  the  PCI  device to the
     framework. Framework supports dynamic changing of the  capa-
     bility  by allowing pci_report_pmcap() to be called multiple
     times. Following are the supported capabilities as indicated
     by the cap:


     PCI_PM_IDLESPEED - The PCI_PM_IDLESPEED value indicates  the
     lowest PCI clock speed that a device can tolerate when idle,
     and is  applicable only to 33 MHz PCI  bus.  arg  represents
     the  lowest  possible  idle speed in KHz (1 KHz is 1000 Hz).
     The integer value representing the speed should be  cast  to
     (void *)before passing as arg to pci_report_pmcap().


     The special values of arg are:

     PCI_PM_IDLESPEED_ANY     The device can  tolerate  any  idle
                              clock speed.






SunOS 5.11         Last change: 13 August 1999                  1






Kernel Functions for Drivers                 pci_report_pmcap(9F)



     PCI_PM_IDLESPEED_NONE    The device cannot tolerate  slowing
                              down of PCI clock even when idle.



     If the driver doesn't make this call,  PCI_PM_IDLESPEED_NONE
     is  assumed. In this case, one offending device can keep the
     entire bus from being power managed.

RETURN VALUES
     The pci_report_pmcap() function returns:

     DDI_SUCCESS    Successful reporting of the capability


     DDI_FAILURE    Failure  to  report  capability  because   of
                    invalid argument(s)


CONTEXT
     The pci_report_pmcap() function can  be  called  from  user,
     kernel and interrupt context.

EXAMPLES
     1. A device driver knows that the device it  controls  works
     with any clock between DC and 33 MHz as specified in Section
     4.2.3.1: Clock Specification  of the PCI  Bus  Specification
     Revision  2.1.  The  device  driver makes the following call
     from its attach(9E):

       if (pci_report_pmcap(dip, PCI_PM_IDLESPEED, PCI_PM_IDLESPEED_ANY) !=
                   DDI_SUCCESS)
                       cmn_err(CE_WARN, "%s%d: pci_report_pmcap failed\n",
                           ddi_driver_name(dip), ddi_get_instance(dip));



     2. A device driver controls  a  10/100  Mb  Ethernet  device
     which runs the device state machine on the chip from the PCI
     clock. For the device state machine to  receive  packets  at
     100  Mb,  the  PCI clock cannot drop below 4 MHz. The driver
     makes the following call whenever it  negotiates  a  100  Mb
     Ethernet connection:

       if (pci_report_pmcap(dip,  PCI_PM_IDLESPEED, (void *)4000) !=
                      DDI_SUCCESS)
                       cmn_err(CE_WARN, "%s%d: pci_report_pmcap failed\n",
                           ddi_driver_name(dip), ddi_get_instance(dip));


ATTRIBUTES




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Kernel Functions for Drivers                 pci_report_pmcap(9F)



     See attributes(5) for descriptions of the  following  attri-
     butes:



     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | Interface Stability         | Committed                   |
    |_____________________________|_____________________________|


SEE ALSO
     Writing Device Drivers


     PCI Bus Power Management Interface Specification Version 1.1


     PCI Bus Specification Revision 2.1



































SunOS 5.11         Last change: 13 August 1999                  3