altera_avgen(4) [freebsd man page]

ALTERA_AVGEN(4) 					   BSD Kernel Interfaces Manual 					   ALTERA_AVGEN(4)

NAME

     altera_avgen -- driver for generic Altera Avalon-bus-attached, memory-mapped devices

SYNOPSIS

     device altera_avgen

     In /boot/device.hints:
     hint.altera_avgen.0.at="nexus0"
     hint.altera_avgen.0.maddr=0x7f00a000
     hint.altera_avgen.0.msize=20
     hint.altera_avgen.0.width=4
     hint.altera_avgen.0.fileio="rw"
     hint.altera_avgen.0.devname="berirom"

DESCRIPTION

     The altera_avgen device driver provides generic support for memory-mapped devices on the Altera Avalon bus.  device.hints entries configure
     the address, size, I/O disposition, and /dev device node name that will be used.  The open(2), read(2), write(2), and mmap(2) system calls
     (and variations) may be used on altera_avgen device nodes, subject to constraints imposed using device.hints entries.  Although reading and
     writing mapped memory is supported, altera_avgen does not currently support directing device interrupts to userspace.

     A number of device.hints sub-fields are available to configure altera_avgen device instances:

     maddr    base physical address of the memory region to export; must be aligned to width

     msize    length of the memory region export; must be aligned to width

     width    Granularity at which read(2) and write(2) operations will be performed.  Larger requests will be broken down into width -sized oper-
	      ations; smaller requests will be rejected.  I/O operations must be aligned to width.

     fileio   allowed file descriptor operations; r authorizes read(2); w authorizes write(2).

     mmapio   allowed mmap(2) permissions; w authorizes PROT_WRITE; r authorizes PROT_READ; x authorizes PROT_EXEC.

     devname  specifies a device name relative to /dev.

     devunit  specifies a device unit number; no unit number is used if this is unspecified.

SEE ALSO

     mmap(2), open(2), read(2), write(2)

HISTORY

     The altera_avgen device driver first appeared in FreeBSD 10.0.

AUTHORS

     The altera_avgen device driver and this manual page were developed by SRI International and the University of Cambridge Computer Laboratory
     under DARPA/AFRL contract (FA8750-10-C-0237) (``CTSRD''), as part of the DARPA CRASH research programme.  This device driver was written by
     Robert N. M. Watson.

BUGS

     altera_avgen is intended to support the writing of userspace device drivers; however, it does not permit directing interrupts to userspace,
     only memory-mapped I/O.

     altera_avgen supports only a nexus bus attachment, which is appropriate for system-on-chip busses such as Altera's Avalon bus.  If the target
     device is off of another bus type, then additional bus attachments will be required.

BSD
								  August 18, 2012							       BSD

DEVICE.HINTS(5) 					      BSD File Formats Manual						   DEVICE.HINTS(5)

NAME

     device.hints -- device resource hints

DESCRIPTION

     The device.hints file is read in by the boot loader(8) when the system is about to start, and its contents are passed to the kernel.  It con-
     tains various variables to control the boot behavior of the kernel.  These variables are typically ``device hints''.

     The file contains one variable per line.  Lines starting with the '#' character are comments and are ignored by the boot loader.

     After the file is read by the boot loader, you may examine the variables with the show command, and may add a new variable, modify an exist-
     ing one, or delete a variable with the set and unset commands of the boot loader (see loader(8)).

     After the system has started, you can dump these variables with the kenv(1) command.

DEVICE HINTS

     Device hint variables are used by device drivers to set up the device.  They are most often used by ISA device drivers to specify where the
     driver will probe for the relevant devices, and what resources it will attempt to use.

     A device hint line looks like:

	   hint.driver.unit.keyword="value"

     where driver is the name of a device driver, unit is the unit number, and keyword is the keyword of the hint.  The keyword may be:

	   at	     specifies a bus to which the device is attached.
	   port      specifies the start address of I/O ports to be used by the device.
	   portsize  specifies the number of ports used by the device.
	   irq	     is the interrupt line number to be used.
	   drq	     is the DMA channel number.
	   maddr     specifies the physical memory address used by the device.
	   msize     specifies the physical memory size used by the device.
	   flags     sets various flag bits for the device.
	   disabled  can be set to "1" to disable the device.

     A device driver may require one or more hint lines with these keywords, and may accept other keywords not listed here, through
     resource_int_value(9).  Consult individual device drivers' manual pages for available keywords and their possible values.

FILES

     /boot/device.hints 	   Device resource hints file.
     /sys/ARCH/conf/GENERIC.hints  Sample resource hints for the GENERIC kernel.
     /sys/ARCH/conf/NOTES	   Notes on the kernel configuration file and device resource hints.

EXAMPLES

     The following example sets up resources for the sio(4) driver on the ISA bus:

	   hint.sio.0.at="isa"
	   hint.sio.0.port="0x3F8"
	   hint.sio.0.flags="0x10"
	   hint.sio.0.irq="4"

     The following example disables the ACPI driver:

	   hint.acpi.0.disabled="1"

SEE ALSO

     kenv(1), loader.conf(5), loader(8), resource_int_value(9)

HISTORY

     The device.hints file first appeared in FreeBSD 5.0.

BSD
								September 11, 2009							       BSD