When the PHY receives low power
sleep requests from the link partner, it enter Sleep Ack mode. In this mode, the
PHY allows 8ms for the MAC to decide if TC-10 sleep mode must be enabled or not.
If the MAC decides to allow TC-10, the PHY proceeds to the next step in TC-10
state machine. However, the MAC can decide to abort TC-10 and the PHY returns to
Normal mode. TC10 can be aborted via register setting by disabling TC10 or via
GPIO. If TC10 is aborted by disabling TC10 feature, then it is recommended to
re-enable TC10 feature once the sleep request has been aborted.