Agilex™ 7 Hard Processor System Technical Reference Manual

ID 683567
Date 8/13/2024
Public
Document Table of Contents

16.4.2.3. FIFO Buffer

The SD/MMC controller has a 4 KB data FIFO buffer for storing transmit and receive data. The FIFO has an ECC controller built-in to provide ECC protection. The ECC controller is able to detect single-bit and double-bit errors, and correct the single-bit errors. The ECC operation and functionality is programmable through the ECC register slave interface. The ECC register slave interface provides host access to configure the ECC logic, as well as, inject bit errors into the memory. It also provides the host access to memory initialization hardware used to clear out the memory contents including the ECC bits. The ECC controller generates interrupts upon occurrences of single- and double-bit errors, and the interrupt signals are connected to the system manager.
Note: Since SD/MMC has multiple memories, it must initialize both memories explicitly. Initialization is controlled by software through the ECC Control (CTRL) register. This process cannot be interrupted or stopped once it starts; hence software must wait for the initialization complete bit to be set in the Initialization Status (INITSTAT) register. Memory accesses are allowed after the initialization process is complete.

For more information about ECC, refer to the Error Checking and Correction Controller chapter.