OSPI-Verification-Framework-UVM

UVM-based verification framework for OSPI controller in SoC designs.

1. Introduction

Serial Peripheral Interface (SPI) is a widely used synchronous serial communication protocol for short-distance, high-speed communication between a master and one or more slave devices. SPI is simple, fast, and flexible, but its data bandwidth is limited by its single-bit data path.

To overcome bandwidth limitations, SPI has evolved into wider variants such as Quad SPI (QSPI) and Octal SPI (OSPI). These variants increase throughput by transferring multiple bits per clock cycle while retaining the fundamental SPI communication model.

This project focuses on the design and verification of an OSPI controller, demonstrating how modern high-speed external memory interfaces are implemented and validated.

2. SPI, QSPI, and OSPI Overview

2.1 Serial Peripheral Interface (SPI)

SPI is a master-slave protocol consisting of four primary signals: SCLK: Serial clock generated by the master MOSI: Master Out, Slave In MISO: Master In, Slave Out CS / SS: Chip Select, used to select a slave device

Key characteristics: One bit transferred per clock cycle Slave selection is done using dedicated chip-select signals No built-in addressing or arbitration Simple hardware implementation

2.2 Quad SPI (QSPI)

QSPI extends SPI by increasing the number of data lines from one to four.

Key enhancements: Uses four bidirectional data lines (IO[3:0]) Transfers four bits per clock cycle Retains SPI-style chip-select-based slave selection Commonly used for higher-speed flash memory access QSPI improves bandwidth without fundamentally changing the SPI protocol.

2.3 Octal SPI (OSPI)

OSPI further extends the SPI concept by using eight data lines.

Key features: Uses eight bidirectional data lines (IO[7:0]) Transfers eight bits per clock cycle Optional DDR (Double Data Rate) operation Optional DQS (Data Strobe) for high-speed sampling Typically used for high-performance external flash memories

Despite its higher speed and complexity, OSPI: Does not introduce device addressing Continues to use chip select for device selection Follows a command → address → data transaction model

🚀 How to Run the Project

For Texas A&M Students

If you are a Texas A&M student with access to the ECEN Linux servers, follow these steps:

1. Clone the repository on the ECEN Linux server:

   git clone <repository-url>
   cd OSPI-Verification-Framework-UVM

2. Load the CSCE-616 environment:

   load-csce-616

   This command sets up all necessary EDA tools, compilers, and simulators for the project.

3. Run the setup script:

   bash setupX.bash

   This script configures the environment and prepares the project for simulation.

4. Navigate to the simulation directory and run the testbench:

   cd sim
   xrun -f run.f

   This command compiles and runs the complete verification environment using the xrun simulator.