Hi,
I'm currently working on updating the DP83867 driver to incorporate support for cable tests with ethtool. During my research, I've consulted the following documents:
- application note: https://www.ti.com/lit/an/snla334/snla334.pdf?ts=1711981773663
- data sheet: https://www.ti.com/lit/ds/symlink/dp83867ir.pdf?ts=1712042512682
In the application note, there are references to three values: peak_indx, peak_val, and peak_sign. After analyzing the documentation, I've concluded that peak_indx corresponds to values retrieved from the TDR_PEAKS_LOC_* registers, and peak_val corresponds to values obtained from the TDR_PEAKS_AMP_* register. However, I'm uncertain about the peak_sign value. My assumption is that the reserved 2 bits in the TDR_PEAKS_AMP_* registers represent the peak_sign values, but I'd like confirmation on whether this interpretation is correct.
Could someone with experience in this area please verify if my understanding is accurate or provide clarification on the peak_sign value in the context of the DP83867 driver's cable testing functionality?
