To complete the target system setup, you will enable the cache allocation capabilities of Intel® TCC Tools. You will run the cache configurator tool to reserve a portion of the L2 and L3 cache. A reserved portion of cache is called software static random-access memory (software SRAM).

Software SRAM enables the cache allocation library to provide low-latency memory buffers to your real-time applications. At the same time, a part of the cache will be removed from general use, potentially reducing the performance of non-real-time applications.

This step reserves the recommended amount of cache for running the cache allocation sample.

To complete target system setup:

1. Confirm that the host is still connected to the target via SSH.

2. In the SSH session, go to the following directory:

   cd /usr/share/tcc_tools/scripts/setup_ssram/

3. Run the following command to add the tcc_buffer driver on the target system. This script adds the tcc_buffer driver to auto load. The cache allocation library interfaces with the driver to provide low-latency buffers.

   ./control_tcc_driver.sh enable

4. Run the following command to remove RTCM temporarily from the boot options.

   ./control_rtcm_sbl.sh disable

5. Reboot the target system.

6. On the host system, ensure that you have copied the keys into $TCC_TOOLS_PATH/keys/sbl, a step that you have done in Step 1: Set up SBL.

7. On the host system, confirm that the host system and target system have a passwordless connection.

   1. Generate a key with an empty passphrase:

      ssh-keygen -t rsa

      NOTE:

      Press Enter when when prompted by the system during the Generating public/private rsa key pair step.

   2. Copy the key to the target system:

      ssh-copy-id <user>@<target>

      NOTE:

      If you do not have ssh-copy-id on your host system, use the command cat .ssh/id_rsa.pub | ssh <user>@<target> 'cat >> .ssh/authorized_keys'

   3. Verify that a password is not required anymore, for example:

      ssh <user>@<target> ls

8. On the host system, go to the tools directory:

   cd ${TCC_TOOLS_PATH}

9. Run the cache configurator tool to reserve a portion of the L2 and L3 cache:

   1. Open the target connection settings file. This command example uses the nano text editor, but you can use any text editor.

      nano ./host_scripts/target_connection_settings.sh

   2. Modify the following fields (see an example below):

      Field Name	Description
      HOSTNAME	Replace hostname with the IP address or host name of the target system.
      USER	Replace user with root.
      SSH_EXTRA	Add any additional SSH command-line options.

      This file contains the hostname and username to connect to the target board through SSH.

      Target connection settings file example:

      HOSTNAME='hostname'
      USER='user'
      SSH_EXTRA=''

   3. Save and close the file.

   4. Run the cache configurator tool.

      ./tcc_cache_configurator.py --environment demo/environment/sample_environment_sbl.json

   5. In the cache configurator tool, enter P.

   6. Select preset number 4.

   7. Enter Y to proceed with the selected configuration.

   8. Enter Y to apply the configuration and go to the reboot screen.

   9. After the target system reboots, enter Y to confirm.

10. Connect to the target via SSH. Replace <target> with the IP address or host name of the target system.

    ssh root@<target>

11. In the SSH session, go to the following directory:

    cd /usr/share/tcc_tools/scripts/setup_ssram/

12. Run the following command to enable RTCM on the target system on the next reboot. Real-time configuration manager (RTCM) is an application that makes it possible to use software SRAM technology on non-virtualized systems.

    ./control_rtcm_sbl.sh enable

13. Run the following command to reboot the target system.

    reboot

Now the system is configured. The software SRAM buffers can be allocated with the cache allocation library.