Building a kernel with the console device drivers

6.14 LPAR mode z/VM guest KVM guest

Control the build options for the console device drivers through the kernel configuration menu.

Kernel builders: This information is intended for those who want to build their own kernel. Be aware that both compiling your own kernel or recompiling an existing distribution usually means that you have to maintain your kernel yourself.

Figure 1 summarizes the kernel configuration menu options that are relevant to the console device drivers. You must select at least one option that adds support for kernel messages to an output device. Select all options to compile a Linux® kernel that supports all available console devices with all their features.

Figure 1. Console kernel configuration menu options

 Device Drivers --->
    ...
    Character devices --->
       ...
       z/VM IUCV Hypervisor console support (VM only)                     (CONFIG_HVC_IUCV)
       ...
       --- S/390 character device drivers (depends on S390) ---
       Support for locally attached 3270 terminals                        (CONFIG_TN3270)     
       ├─ Support for tty input/output on 3270 terminals                  (CONFIG_TN3270_TTY) 
       ├─ Support for fullscreen applications on 3270 terminals           (CONFIG_TN3270_FS)  
       └─ Support for console on 3270 terminal                            (CONFIG_TN3270_CONSOLE)*
       Support for 3215 line mode terminal                                (CONFIG_TN3215)     
       └─ Support for console on 3215 line mode terminal                  (CONFIG_TN3215_CONSOLE)
       Support for SCLP line mode terminal                                (CONFIG_SCLP_TTY)   
       └─ Support for console on SCLP line mode terminal                  (CONFIG_SCLP_CONSOLE)
       Support for SCLP VT220-compatible terminal                         (CONFIG_SCLP_VT220_TTY)
       └─ Support for console on SCLP VT220-compatible terminal           (CONFIG_SCLP_VT220_CONSOLE)

CONFIG_HVC_IUCV: Adds the z/VM® IUCV HVC device driver and IUCV support. This device driver supports terminal access through the iucvconn program to instances of Linux on z/VM.
CONFIG_TN3270: Adds the 3270 terminal device driver. This device driver supports IBM® 3270 terminal hardware and 3270 terminal emulations.
CONFIG_TN3270_TTY: Adds the terminal input and output support to the 3270 terminal device driver.
CONFIG_TN3270_FS: Adds limited support for full-screen applications the 3270 terminal device driver.
CONFIG_TN3270_CONSOLE: Adds the operating system messages view to the 3270 terminal device driver.
CONFIG_TN3215: Adds the 3215 line-mode terminal device driver. Through a translation between the 3215 protocol and the 3270 protocol within z/VM, this device driver supports IBM 3270 terminal hardware and 3270 terminal emulations.
CONFIG_TN3215_CONSOLE: Adds support for kernel messages to the 3215 line-mode terminal device driver.
CONFIG_SCLP_TTY: Adds the SCLP line-mode terminal device driver. This device driver supports the Operating System Messages applet on the HMC.
CONFIG_SCLP_CONSOLE: Adds support for kernel messages to the SCLP line-mode terminal device driver.
CONFIG_SCLP_VT220_TTY: Adds the VT220-compatible SCLP VT220 terminal device driver. This device driver supports the Integrated ASCII console applet on the HMC.
CONFIG_SCLP_VT220_CONSOLE: Adds support for kernel messages to the SCLP VT220 terminal device driver.

Linux requires a device for writing kernel messages early in the boot process. Always compile the console device drivers and their components into the kernel.