CCM

Table of Contents

• Features Supported
• SysConfig Features
• Features NOT Supported
• Important Usage Guidelines
• Example Usage
• API

Features Supported

The Compute Compare Module (CCM) is the R5F sub-system’s implementation for the lockstep error detection logic. The R5F sub-system, when bootstrapped to lockstep mode, has a logic that compares the outputs of the two cores and asserts an interrupt whenever an error is detected. There is also a logic to test the comparison logic.

The CCM module provides APIs to:

• Initialize the R5F CCM for the operating modes and verify the config
• Perform Self-test of the supported operating modes (normal and error forcing)
• Inject an error
• Read back the static config registers
• Clear errors that have occurred due to error injection or actual fault

SysConfig Features

• None

Features NOT Supported

• None

Important Usage Guidelines

• None

Example Usage

The following shows an example of SDL R5F CCM API usage by the application.

Initialize the R5F CCM instance

retVal = SDL_CCM_init(SDL_R5SS0_CCM);
if (result != SDL_PASS)
{
    DebugP_log("CCM_Test_init: Error result = %d\n", result);
    retValue = -1;
}
else
{
    DebugP_log("\nCCM_Test_init: CCM Init complete \n");
}

Verify the configuration

result = SDL_CCM_verifyConfig(0);
if (result != SDL_PASS)
{
    DebugP_log("R5F-CPU example application CCM_Test_init: Error result = %d\n", result);
    retValue = -1;
}
else
{
    DebugP_log("\nR5F-CPU example application CCM_Test_init: CCM Init complete \n");
}

Perform a self-test:

result = SDL_CCM_selfTest(SDL_R5SS0_CCM,
                          SDL_CCM_MONITOR_TYPE_OUTPUT_COMPARE_BLOCK,
                          SDL_CCM_SELFTEST_TYPE_NORMAL, 0U,
                          10000000);
 
if (result != SDL_PASS )
{
    DebugP_log("\n R5F-CPU example application CCM self test failed");
    retVal = -1;
}
else
{
    DebugP_log("\n R5F-CPU example application CCM Self Test complete");
}

Inject an error:

result = SDL_CCM_injectError(SDL_R5SS0_CCM, SDL_CCM_MONITOR_TYPE_OUTPUT_COMPARE_BLOCK);
 
if (result != SDL_PASS ) {
    DebugP_log("\n R5F-CPU example application CCM inject failed");
   retVal = -1;
} else {
    DebugP_log("\n R5F-CPU example application CCM inject Test complete");
}

API

APIs for CCM MODULE