2.4. Test Modes
CSR_CFG[4:2] configures the test mode. The following four tests are available:
- LPBK1: This is a memory copy test. The AF copies CSR_NUM_LINES from the source buffer to the destination buffer. Upon test completion, the software compares the source and destination buffers.
- Read: This test stresses the read path and measures read bandwidth or latency. The AF reads CSR_NUM_LINES starting from the CSR_SRC_ADDR. This is only a bandwidth or latency test. It does not verify the data read.
- Write: This test stresses the write path and measures write bandwidth or latency. The AF writes CSR_NUM_LINES starting from the CSR_SRC_ADDR. This is only a bandwidth or latency test. It does not verify the data written.
- TRPUT: This test combines the reads and writes. It reads CSR_NUM_LINES starting from CSR_SRC_ADDR location and writes CSR_NUM_LINES to CSR_SRC_ADDR. It also measures read and write bandwidth. This test does not check the data. The reads and writes have no dependencies.
The following table shows the CSR_CFG encodings for the four tests. This table sets and CSR_NUM_LINES, <N>=14. You can change the number of cache lines by updating the CSR_NUM_LINES register.
| Test Mode | Encoding CSR_CFG[4:2] | Cache Line Threshold CSR_NUM_LINES | Cache Line Threshold for <N>=14 |
|---|---|---|---|
| LPBK1 | 3'b000 | 2<N> | 14'h3FFF |
| Read | 3'b001 | 2<N> | 14'h3FFF |
| Write | 3'b010 | 2<N> | 14'h3FFF |
| TRPUT | 3'b011 | 2<N> | 14'h3FFF |