Driver Entry Points quiesce(9E)
NAME
quiesce - quiesce a device
SYNOPSIS
#include
#include
int prefixquiesce(dev_info_t *dip);
int ddi_quiesce_not_needed(dev_info_t *dip);
INTERFACE LEVEL
Solaris DDI specific (Solaris DDI)PARAMETERS
dip A pointer to the device's dev_info structure.
DESCRIPTION
The quiesce() function quiesces a device so that the device
no longer generates interrupts, modifies or accesses memory. The driver should reset the device to a hardware state from which the device can be correctly configured by the driver'sattach() routine without a system power cycle or being con-
figured by the firmware. For devices with a defined reset state configuration, the driver should return that device tothat state as part of the quiesce operation. Fast Reboot,
where firmware is bypassed when booting to a new OS image, is such a case.quiesce() is only called for an attached device instance as
one of the final operations of a reboot sequence, and no other thread can be active for this device. The system guarantees that no other driver entry point is active orinvoked while quiesce() is invoked. The system also guaran-
tees that no timeout or taskq is invoked. The system issingle-threaded and can not be interrupted. Therefore, the
driver's quiesce() implementation must not use locks or
timeouts, or rely on them being called. The driver must dis-
card all outstanding I/O instead of waiting for completion.
At the conclusion of the quiesce() operation, the driver
must guarantee that the device no longer has access to memory or interrupts.The only DDI interfaces that can be called by the quiesce()
implementation are non-blocking functions, such as the
ddi_get*() and ddi_put*() functions.
SunOS 5.11 Last change: 16 Sep 2008 1
Driver Entry Points quiesce(9E)
If quiesce() determines a particular instance of the device
cannot be quiesced when requested because of some excep-
tional condition, quiesce() returns DDI_FAILURE. This rarely
happens. If a driver has previously implemented the obsolete reset()interface, its functionality must be merged into quiesce().
The driver's reset() routine is no longer called if animplementation of quiesce() is present.
ddi_quiesce_not_needed() always returns DDI_SUCCESS. A
driver can set its devo_quiesce device function to
ddi_quiesce_not_needed() to indicate that the device it
manages does not need to be quiesced.
RETURN VALUES
quiesce() returns the following:
DDI_SUCCESS The device has been successfully quiesced.
DDI_FAILURE The operation failed.
CONTEXT
This function is called from kernel context only.SEE ALSO
reboot(1M), uadmin(1M), uadmin(2), attach(9E), detach(9E),ddi_add_intr(9F), ddi_map_regs(9F), pci_config_setup(9F),
timeout(9F), dev_ops(9S)
NOTESWhen quiesce() is called, the system is single-threaded,
therefore the driver's quiesce() implementation must not be
blocked. For example, the implementation must not create or tear down mappings, call FMA functions, or create or cancel callbacks.SunOS 5.11 Last change: 16 Sep 2008 2