This chapter describes how to access and modify nonvolatile RAM (NVRAM) configuration variables. Its sections include:

• System Configuration Variables

• Displaying and Changing Variable Settings

• Setting Security Variables

• Changing the Power-On Banner

• Input and Output Control

• Selecting Boot Options

• Controlling Power-On Self-Test (POST)

• Using nvramrc

The procedures described in this chapter assume that the user interface is active. See Chapter 1 for information about starting the user interface.

System configuration variables are stored in the system NVRAM . These variables determine the start-up system configuration and related communication characteristics. You can modify the values of the configuration variables, and any changes you make remain in effect even after a power cycle. Configuration variables should be adjusted cautiously.

TABLE 3-1 lists a typical set of NVRAM configuration variables defined by IEEE Standard 1275-1994 .

NVRAM configuration variables can be viewed and changed using the commands listed in TABLE 3-2 .

The following pages show how these commands can be used.

To display a list of the current variable settings on your system, type:

ok printenv 

Variable Name           Value                Default Value

oem-logo

oem-logo?               false                false

oem-banner

oem-banner?             false                false

output-device           ttya                 screen

input-device            ttya                 keyboard

diag-file

diag-device             net                  net

boot-file

boot-device             disk                 disk net

auto-boot?              false                true

fcode-debug?            true                 false

use-nvramrc?            false                false

nvramrc

screen-#columns         80                  80

screen-#rows            34                  34

security-mode           none                none

security-password

security-#badlogins     0

diag-switch?            true                false

ok

In the displayed, formatted list of the current settings, numeric variables are often shown in the decimal format.

To change a variable setting, type:

ok setenv variable-name value 

variable-name is the name of the variable. value is a numeric value or text string appropriate to the named variable. A numeric value is interpreted as a decimal number, unless preceded by 0x , which is the qualifier for a hexadecimal number.

For example, to set the auto-boot? variable to false , type:

ok setenv auto-boot? false

ok 

You can reset one or most of the variables to the original defaults using the set-default variable and set-defaults commands.

For example, to reset the auto-boot? variable to its default setting (true), type:

ok set-default auto-boot?

ok

To reset most variables to their default settings, type:

ok set-defaults

ok

On many SPARC systems, you can reset the NVRAM variables to their default settings by holding down Stop-N while the system is powering up. When issuing this command, hold down Stop-N immediately after turning on the power to the SPARC system, and keep it pressed for a few seconds or until you see the banner (if the display is available). This is a good technique to force a SPARC compatible system's NVRAM variables to a known condition. See also Appendix C .

The NVRAM system security variables are:

• security-mode

• security-password

• security-#badlogins

security-mode can restrict the set of operations that users are allowed to perform from the user interface. The three security modes, and their available commands, are listed in the following table in the order of most to least secure.

Command Security

With security-mode set to command :

• A password is not required if you type the boot command by itself. However, if you use the boot command with an argument, a password is required.

• The go command never asks for a password.

• A password is required to execute any other command.

Examples are shown in the following screen.

ok boot					(no password required)

ok go					(no password required)

ok boot filename	 				(password required)

Password:					(password is not echoed as it is typed)

ok reset-all					(password required)

Password:					(password is not echoed as it is typed) 

Caution Caution - It is important to remember your security password and to set the security password before setting the security mode. If you forget this password, you cannot use your system; you must call your vendor's customer support service to make your system bootable again.

To set the security password and command security mode, type the following at the ok prompt:

ok password 

ok New password (only first 8 chars are used):

ok Retype new password:

ok setenv security-mode command 

ok

The security password you assign must be between zero and eight characters. Any characters after the eighth are ignored. You do not have to reset the system; the security feature takes effect as soon as you type the command.

If you enter an incorrect security password, there will be a delay of about 10 seconds before the next boot prompt appears. The number of times that an incorrect security password is typed is stored in the security-#badlogins variable.

Full Security

The full security mode is the most restrictive. With security-mode set to full :

• A password is required any time you execute the boot command.

• The go command never asks for a password.

• A password is required to execute any other command.

Here are some examples.

ok go					(no password required)

ok boot					(password required)

Password:				(password is not echoed as it is typed)

ok boot filename 					(password required)

Password:				(password is not echoed as it is typed)

ok reset-all					(password required)

Password:					(password is not echoed as it is typed)

Caution Caution - It is important to remember your security password and to set the security password before setting the security mode. If you forget this password, you cannot use your system; you must call your vendor's customer support service to make your system bootable again.

To set the security password and full security mode, type the following at the ok prompt:

ok password 

ok New password (only first 8 chars are used):

ok Retype new password:

ok setenv security-mode full 

ok

The banner configuration variables are:

• oem-banner

• oem-banner?

• oem-logo

• oem-logo?

To view the power-on banner, type:

ok banner 

Sun Ultra 1 SBus (UltraSPARC 167 MHz),Keyboard Present

PROM Rev. 3.0, 64MB memory installed, Serial # 289

Ethernet address 8:0:20:d:e2:7b, Host ID: 80000121

ok

The banner for your system will be different.

The banner consists of two parts: the text field and the logo (over serial ports, only the text field is displayed). You can replace the existing text field with a custom text message using the oem-banner and oem-banner? configuration variables.

To insert a custom text field in the power-on banner, type:

ok setenv oem-banner Hello Mom and Dad

ok setenv oem-banner? true

ok banner

 Hello Mom and Dad

ok

The system displays the banner with your new message, as shown in the preceding screen.

The graphic logo is handled differently. oem-logo is a 512-byte array, containing a total of 4096 bits arranged in a 64 x 64 array. Each bit controls one pixel. The most significant bit (MSB) of the first byte controls the upper-left corner pixel. The next bit controls the pixel to the right of it, and so on.

To create a new logo, first create a Forth array containing the correct data; then copy this array into oem-logo . The array is then installed in oem-logo with $setenv . The example below fills the top half of oem-logo with an ascending pattern.

ok create logoarray d# 512 allot

ok logoarray d# 256 0 do i over i + c! loop drop

ok logoarray d# 256 " oem-logo" $setenv

ok setenv oem-logo? true

ok banner 

To restore the system's original power-on banner, set the oem-logo? and oem-banner? variables to false .

ok setenv oem-logo? false

ok setenv oem-banner? false

ok

Because the oem-logo array is so large, printenv displays approximately the first 8 bytes (in hexadecimal). To display the entire array, type oem-logo dump . The oem-logo array is not erased by set-defaults , since it might be difficult to restore the data. However, oem-logo? is set to false when set-defaults executes, so the custom logo is no longer displayed.

The console is used as the primary means of communication between OpenBoot and the user. The console consists of an input device, used for receiving information supplied by the user, and an output device, used for sending information to the user. Typically, the console is either the combination of a text/graphics display device and a keyboard or an ASCII terminal connected to a serial port.

The configuration variables related to the control of the console are:

• input-device

• output-device

• screen-#columns

• screen-#rows

You can use these variables to assign the power-on defaults for the console. These values do not take effect until after the next power cycle or system reset.

Selecting Input and Output Device Options

The input-device and output-device variables control the firmware's selection of input and output devices after a power-on reset. The default input-device value is keyboard and the default output-device value is screen . The values of input-device and output-device must be device specifiers. The aliases keyboard and screen are often used as the values of these variables.

When the system is reset, the named device becomes the initial firmware console input or output device. (If you want to temporarily change the input or output device, use the input or output commands described in Chapter 4 ).

To set ttya as the initial console input device, type:

ok setenv input-device ttya

ok

If you select keyboard for input-device , and the device is not plugged in, input is accepted from a fallback device (typically ttya ) after the next power cycle or system reset. If you select screen for output-device , but no frame buffer is available, output is sent to the fall-back device after the next power cycle or system reset.

To specify an SBus frame buffer as the default output device (especially if there are multiple frame buffers in the system), type:

ok setenv output-device /sbus/SUNW,leo 

ok 

Serial Port Characteristics

The following values represent the typical range of communications characteristics for serial ports:

• baud = 110, 300, 1200, 2400, 4800, 9600, 19200, or 38400 bits/second

• #bits = 5, 6, 7, or 8 (data bits)

• parity = n (none), e (even), or o (odd), parity bit

• #stop = 1 (1), (1.5), or 2 (2) stop bits

You can use the auto-boot? configuration variable to determine whether or not the system boots automatically after a power cycle or system reset.

If auto-boot? is true and if OpenBoot is not in diagnostic mode, the system boots automatically after a power-cycle or system reset using the boot-device and boot-file values.

If auto-boot? is true and if OpenBoot is in diagnostic mode, the system boots automatically after a power-cycle or system reset using the diag-device and diag-file values.

These variables can also be used during manual booting to select the boot device and the program to be booted. For example, to specify default booting from the network server, type:

ok setenv boot-device net 

ok 

Changes to boot-file, boot-device , diag-file, and diag-device take effect the next time that boot is executed.

The Power-on Testing variables are:

• diag-switch?

• diag-level

Setting diag-switch? to true causes the function diagnostic-mode? to return true . When diagnostic-mode? returns true , the system:

• Performs more thorough self tests during any subsequent power-on or system reset process. The coverage of self tests executed depends on the value of diag-level. For maximum coverage, set the diag-level value to max .

• May display additional status messages (the details are implementation dependent).

• Uses different configuration variables for booting. For more details on the effects on the boot process, see Chapter 2 .

Most systems have a factory default of false for the diag-switch? variable. To set diag-switch? to true , type:

ok setenv diag-switch? true 

ok

To set diag-switch? to false , type:

ok setenv diag-switch? false 

ok

When not in diagnostic mode, the system does not announce the diagnostic tests as they are performed (unless a test fails) and may perform fewer tests.

You can use the nvramrc configuration variable store user-defined commands executed during start-up. The contents of the variable are called the script.

Typically, nvramrc is used by a device driver to save start-up configuration variables, to patch device driver code, or to define installation-specific device configuration and device aliases. It can also be used for bug patches or for user-installed extensions. Commands are stored in ASCII, just as the user would type them at the console.

If the use-nvramrc? configuration variable is true , the script is evaluated during the OpenBoot start-up sequence as shown:

1. Perform power-on self-test (POST)

2. Perform system initialization

3. Evaluate the script (if use-nvramrc? is true )

4. Execute probe-all (evaluate FCode)

5. Execute install-console

6. Execute banner

7. Execute secondary diagnostics

8. Perform default boot (if auto-boot? is true )

It is sometimes desirable to modify the sequence probe-all install-console banner . For example, commands that modify the characteristics of plug-in display devices may need to be executed after the plug-in devices have been probed, but before the console device has been selected. Such commands would need to be executed between probe-all and install-console . Commands that display output on the console would need to be placed after install-console or banner .

This is accomplished by creating a custom script which contains either banner or suppress-banner since the sequence probe-all install-console banner is not executed if either banner or suppress-banner is executed from the script. This allows the use of probe-all , install-console, and banner inside the script, possibly interspersed with other commands, without having those commands re-executed after the script finishes.

Most user interface commands can be used in the script. The following cannot:

• boot

• go

• nvedit

• password

• reset-all

• setenv security-mode

Editing the Contents of the Script

The script editor, nvedit , lets you create and modify the script using the commands listed in TABLE 3-4 .

Use the editing commands shown in TABLE 3-5 in the script editor.

Activating the Script

Use the following steps to create and activate the script:

1. At the ok prompt, type nvedit.

Edit the script using editor commands.

2. Press Control-C to get out of the editor and back to the ok prompt.

If you have not yet typed nvstore to save your changes, you may type nvrun to execute the contents of the temporary edit buffer.

3. Type nvstore to save your changes.

4. Enable the interpretation of the script by typing:

setenv use-nvramrc? true

5. Type reset-all to reset the system and execute the script, or execute the contents directly by typing:

nvramrc evaluate

Example Script

The following example shows you how to create a simple colon definition in the script.

ok nvedit 

0: : hello ( -- ) 

1: ." Hello, world. " cr 

2: ; 

3: ^C 

ok nvstore 

ok setenv use-nvramrc? true 

ok reset-all 

...

ok hello 

Hello, world.

ok 

Notice the nvedit line number prompts ( 0: , 1: , 2: , 3: ) in the above example. These prompts are system-dependent.

OpenBoot 4.x Command Reference Manual

816-1177-10

Copyright © 2002, Sun Microsystems, Inc. All rights reserved.