DLL On to DLL Off Procedure

To switch from DLL On mode to DLL Off mode, follow the procedure below:

1. Make sure no access is in progress and Self-refresh mode is disabled.
2. Set MPDDRC_CR.DIS_DLL to 1.
3. Enable Self-refresh mode and set MPDDRC_LPR.UPD_MR to 2.
4. Wait until self-refresh is performed, then read MPDDRC_LPR.SELF_DONE.
5. Set MPDDRC_LPR.CHG_FREQ to 1 and MPDDRC_LPR.UPD_MR to 0.
6. Change the frequency. The maximum value is 125 MHz, but some providers allow 200 MHz.
7. In MPDDRC_CR, update appropriate values: Reset DLL (DLL), CAS read latency (CAS), CAS write latency (CAS_WR). DLL must be set to 0. Update other bit fields depending on the Frequency and DLL Off parameter settings.
8. Update all asynchronous timings (TRAS, TRP, TXSRD, etc.) in MPDDRC_TPR0, MPDDRC_TPR1 and MPDDRC_TPR2 depending on the Frequency and DLL Off parameter settings
9. Perform an access to DRAM.
10. DLL is now disabled.