virtio_blk(4) [freebsd man page]

VIRTIO_BLK(4)						   BSD Kernel Interfaces Manual 					     VIRTIO_BLK(4)

NAME

     virtio_blk -- VirtIO Block driver

SYNOPSIS

     To compile this driver into the kernel, place the following lines in your kernel configuration file:

	   device virtio_blk

     Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):

	   virtio_blk_load="YES"

DESCRIPTION

     The virtio_blk device driver provides support for VirtIO block devices.

LOADER TUNABLES

     Tunables can be set at the loader(8) prompt before booting the kernel or stored in loader.conf(5).

     hw.vtblk.no_ident

     hw.vtblk.X.no_ident

	     These tunables disable retrieving the device identification string from the hypervisor either globally or per-device.  The default
	     value is 0.

     hw.vtblk.writecache_mode

     hw.vtblk.X.writecache_mode

	     These tunables determine the write cache mode globally or per-device.  The mode can changed only if the ConfigWCE feature is negoti-
	     ated.  Set to 0 for writethrough mode, 1 for writeback mode, and -1 to leave it as-is.  The default value is to leave as-is.

SYSCTL VARIABLES

     The following variables are available as sysctl(8) variables.

     dev.vtblk.X.writecache_mode

	     The write cache mode of the device can be either writethrough (0) or writeback (1).  If the ConfigWCE feature is negotiated, the
	     write cache mode can be toggled between writethrough and writeback.

SEE ALSO

     virtio(4)

HISTORY

     The virtio_blk driver was written by Bryan Venteicher <bryanv@FreeBSD.org>.  It first appeared in FreeBSD 9.0.

BSD
								   July 2, 2013 							       BSD

SND_VIA8233(4)						   BSD Kernel Interfaces Manual 					    SND_VIA8233(4)

NAME

     snd_via8233 -- VIA Technologies VT8233 bridge device driver

SYNOPSIS

     To compile this driver into the kernel, place the following lines in your kernel configuration file:

	   device sound
	   device snd_via8233

     Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):

	   snd_via8233_load="YES"

DESCRIPTION

     The snd_via8233 bridge driver allows the generic audio driver, sound(4), to attach to the VIA VT8233 audio devices.  These audio chipsets are
     integrated in the southbridge on many VIA based motherboards.

   Runtime Configuration
     The following sysctl(8) variables are available in addition to those available to all sound(4) devices:

	   dev.pcm.%d.polling  Experimental polling mode, where the driver operates by querying the device state on each tick using callout(9).
			       Polling is disabled by default.	Do not enable it unless you are facing weird interrupt problems or if the device
			       cannot generate interrupts at all.

HARDWARE

     The snd_via8233 driver supports the following audio chipsets:

     o	 VIA VT8233
     o	 VIA VT8233A
     o	 VIA VT8233C
     o	 VIA VT8235
     o	 VIA VT8237
     o	 VIA VT8251

SEE ALSO

     sound(4)

HISTORY

     The snd_via8233 device driver first appeared in FreeBSD 4.7.

AUTHORS

     This manual page was written by Joel Dahl <joel@FreeBSD.org>.

BUGS

     The snd_via8233 driver does not support S/PDIF.  There is partial support in the code, so implementing it should be fairly easy if the right
     hardware is available.

BSD
								 November 29, 2006							       BSD