pci, pci_read_config, pci_write_config, pci_enable_busmaster,
pci_disable_busmaster, pci_enable_io, pci_disable_io, pci_set_powerstate,
pci_get_powerstate, pci_find_bsf, pci_find_device -- PCI bus interface
pci_write_config(device_t dev, int reg, u_int32_t val, int width);
pci_enable_io(device_t dev, int space);
pci_disable_io(device_t dev, int space);
pci_set_powerstate(device_t dev, int state);
pci_read_config(device_t dev, int reg, int width);
pci_find_bsf(u_int8_t, u_int8_t, u_int8_t);
The pci set of functions are used for managing PCI devices.
The pci_read_config() function is used to read data from the PCI configuration
space of the device dev, at offset reg, with width specifying the
size of the access.
The pci_write_config() function is used to write the value val to the PCI
configuration space of the device dev, at offset reg, with width specifying
the size of the access.
The pci_enable_busmaster() function enables PCI bus mastering for the
device dev, by setting the PCIM_CMD_BUSMASTEREN bit in the PCIR_COMMAND
register. The pci_disable_busmaster() function clears this bit.
The pci_enable_io() function enables memory or I/O port address decoding
for the device dev, by setting the PCIM_CMD_MEMEN or PCIM_CMD_PORTEN bit
in the PCIR_COMMAND register appropriately. The pci_disable_io() function
clears the appropriate bit. The state argument specifies which resource
is affected; this can be either SYS_RES_MEMORY or SYS_RES_IOPORT as
NOTE: These functions should be used in preference to manually manipulating
the configuration space.
The pci_get_powerstate() function returns the current ACPI power state of
the device dev. If the device does not support power management capabilities,
then the default state of PCI_POWERSTATE_D0 is returned. The following
power states are defined by ACPI:
PCI_POWERSTATE_D0 State in which device is on and running. It is
receiving full power from the system and delivering
full functionality to the user.
PCI_POWERSTATE_D1 Class-specific low-power state in which device
context may or may not be lot. Buses in this
state cannot do anything to the bus, to force
devices to loose context.
PCI_POWERSTATE_D2 Class-specific low-power state in which device
context may or may not be lost. Attains greater
power savings than PCI_POWERSTATE_D1. Buses in
this state can cause devices to loose some context.
Devices must be prepared for the bus to be
in this state or higher.
PCI_POWERSTATE_D3 State in which the device is off and not running.
Device context is lost, and power from the device
can be removed.
PCI_POWERSTATE_UNKNOWN State of the device is unknown.
The pci_set_powerstate() function is used to transition the device dev to
the ACPI power state state. It checks to see if the device is PCI 2.2
compliant. If so, it checks the capabilities pointer to determine which
power states the device supports. If the device does not have power management
capabilities, the default state of PCI_POWERSTATE_D0 is set.
The pci_find_bsf() function looks up the device_t of a PCI device, given
its bus, slot, and function.
The pci_find_device() function looks up the device_t of a PCI device,
given its vendor and device IDs. Note that there can be multiple matches
for this search; this function only returns the first matching device.
The pci_addr_t type is varies according to the size of the PCI bus
address space on the target architecture.
pci(4), pciconf(8), bus_alloc_resource(9), bus_dma(9),
bus_release_resource(9), bus_setup_intr(9), bus_teardown_intr(9),
devclass(9), device(9), driver(9), rman(9)
"NewBus", FreeBSD Developers' Handbook,
Shanley and Anderson, PCI System Architecture, Addison-Wesley, 2nd
Edition, ISBN 0-201-30974-2.
This man page was written by Bruce M Simpson <email@example.com>.
This manual page does not yet document PAE and how it affects memoryspace
mapping of PCI devices.
FreeBSD 5.2.1 May 21, 2003 FreeBSD 5.2.1 [ Back ]