BIST Disk Test Module

Overview

The disk test module verifies the performance of USB and SD interfaces on the AMD Kria™ starter kits.

Tests

The module contains self validating performance test. It uses “dd” command-line utility to check the performance of USB and SD disk interfaces and verifies if the measured read/write speeds are greater than the specified threshold speeds. The test provides performance verification for different modes such as read, write, and read_write (optional) suites.

The config parameters for the test are described below:

  • label: The test label

  • hw_path: The USB/SD hardware path enumeration on the device

  • mode: The mode of the performance test (read, write or read_write)

The disk performance test obtains the port name and number from the test label and retrieves the disk partition, USB/SD device path and speed standard of the device connected to the interface using get_dev_path_speed() function. The module then verifies if the available space on the device is greater than 128MiB using check_disk_space() function and mounts it for read and write transaction between the device and the starter kit.

Depending on the mode of the test, read or write performance of the interfaces are verified using dd command-line utility by get_read_speed() or get_write_speed() functions and the result is logged by log_disk_performance(). The device is unmounted after the test execution.

For KV260 and KR260 starter kits, there are four USB ports and one SD card port. The mapping for the test labels to the four USB ports is given below:

Test Label USB Port
usb1_* Top Left
usb2_* Bottom Left
usb3_* Top Right
usb4_* Bottom Right

For KD240 starter kit, there are two USB ports and one SD card port. The mapping for the test labels to the two USB ports is given below:

Test Label USB Port
usb1_* Top
usb2_* Bottom

Test Execution

Example commands for this module are provided below (KV260):

pytest-3 --board kv260 -m disk  // Run all tests in this module
pytest-3 --board kv260 -k usb1_read_performance  // Run read performance test for USB1 port
pytest-3 --board kv260 -k usb1_write_performance  // Run write performance test for USB1 port
pytest-3 --board kv260 -k sd_read_performance  // Run read performance test for SD port
pytest-3 --board kv260 -k sd_write_performance  // Run write performance test for SD port

For each interface, the test prints out the device path, speed standard of the device connected, along with minimum expected read/write speed and measured speed. The log indicates whether the performance test is pass or fail based on the measured and threshold speed comparison.

Test Debug

  • Make sure that the USB/SD card media is inserted correctly to the interface under test.

  • Verify that there is a minimum of 128MiB of storage space available for performing read/write transaction on the device connected to the interface.

Known Issues and Limitations

  • The disk test is limited to verifying the read and write performances of USB and SD ports only.

  • Read and write performance speeds depend on the actual device under test and varies greatly on the manufacturer and model. The obtained performance numbers are to be reviewed by the user and not an indication of max achievable performance.

  • There is a known issue that for some USB/SD ports read and write performance, speeds fall slightly below the threshold speeds given in the following table. In this case, the performance can be verified manually based on the device manufacturer and model.

Mode SD Speed C-class SD Speed UHS-class USB-SD Speed class USB 2.0 USB 3.0
Read 6MBps 12MBps 6MBps 9MBps 80MBps
Write 2MBps 6MBps 2MBps 2MBps 8MBps

  • The threshold speeds are established based on the experimentation conducted on different devices as shown in the following tables. The read and write speeds indicated are an average of multiple iterations with a 20% error margin.

USB devices:

Model Class Read Write
SanDisk Cruzer - SDCZ600-016G USB 3.0 100MBps 12MBps
SanDisk Ultra - SDCZ48-016G USB 3.0 102MBps 8MBps
SanDisk Ultra fair - SDCZ73-032G USB 3.0 120MBps 12MBps
SanDisk Ultra Eco - SDCZ96-064G USB 3.2 80MBps 12MBps
SanDisk Cruzer - SDCZ36-004G USB 2.0 9MBps 2MBps
SanDisk Cruzer Blade - SDCZ50-016G USB 2.0 24MBps 7MBps
DataTraveler 101 G2 - DT101G2-016G USB 2.0 18MBps 6MBps

MicroSD devices:

For the MicroSD devices, there are two variants in the same model that match both theoretical speeds of SD Speed C-class and SD Speed UHS-class.

Model Class Read Write
SanDisk Ultra 16GB - HC Class 10 (White/Grey) SD Speed C-class 6MBps 2MBps
SanDisk Ultra 16GB - HC Class 10 (Red/Grey) SD Speed UHS-class 12MBps 6MBps

Next Steps

  1. BIST Overview

Copyright © 2023 Advanced Micro Devices, Inc

Terms and Conditions