Display substrate and display device

A display substrate, comprising:

• a base substrate having a display region and a peripheral region surrounding the display region;
• a plurality of sub-pixels in the display region;
• a plurality of data lines in the display region, electrically coupled to the plurality of sub-pixels respectively, and configured to provide a data signal to the plurality of sub-pixels respectively;
• a plurality of pads in the peripheral region, wherein at least a portion of the plurality of pads are configured to provide a data signal to the plurality of data lines respectively;
• at least one test data signal line in the peripheral region;
• at least one test control signal line in the peripheral region;
• and
• a plurality of test units in the peripheral region and on a side of the plurality of pads away from the display region, wherein
• at least one of the plurality of test units is electrically coupled to the at least one test data signal line, the at least one test control signal line and at least one data line of the plurality of data lines respectively, and configured to transmit a signal provided by the at least one test data signal line to the at least one data line according to a signal provided by the at least one test control signal line.