vdev pl011

Emulate a PL011 serial device

Synopsis:

vdev pl011 options

Options:

batch timeout
Instead of writing one character at a time, batch the output until the number of microseconds specifed by timeout has passed with no new characters coming in.
delayed seconds|forever
Delay opening the host device until it is first referenced by the guest.
If the device isn't found in the host, keep trying to find the device for the number of seconds given by seconds before timing out (e.g., delayed 5). If seconds is set to 0 (i.e., delayed 0), try only once to find the device. If it is set to forever (i.e., delayed forever), never time out and just keep trying to find the device.
hostdev [<|>]host_device_name
hostdev >"|command_string"
The first form means use the host_device_name as the source and/or destination of characters for the vdev.

For a given hostdev option, you can use one of < (input) or > (output) so the host device specified by host_device_name provides input or receives output.

To specify separate input and output devices, you can use multiple hostdev options:
hostdev <myhostinputdevice
hostdev >myhostoutputdevice
Or, you can use neither < nor > to indicate the same device is used for both input and output:
hostdev myhostdevice
The second form means redirect the vdev's output to a process created by executing command_string. The command string must be immediately preceded by the pipe character (|) and then surrounded by double quotes, as shown here:
hostdev >"|/guests/tee /guests/pipe_test.log"

Here the vdev's output is sent as input to the /guests/tee program which takes the pathname of a log file, /guests/pipe_test.log, as an argument. The command you name can do whatever you want; for example, it could perform logging with file size limits. For further explanation, refer to Logging output in the vdev virtio-console reference.

name device_path
Specify a device path that you can write commands to in order to control the size and number of log files created for storing the vdev's output. For example, you can issue a command to reopen a log file (i.e., truncate it to zero bytes) after you noticed it was getting too big. For information about performing this log rotation, refer to Logging output in the vdev virtio-console reference.
sched priority
Send pulses indicating available input on the host device with a priority level of priority.

For a list of options available to all vdevs, see Common vdev options at the beginning of this chapter.

Description:

ARM only. The pl011 vdev emulates a PL011 serial device.

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