How to change serial clock frequency in QSPI configuration parameters

[takashi_kojima]

Hello, Community.

Is there a way to change the serial clock frequency in the QSPI configuration parameters after system startup?

I want to set the serial clock frequency in the QSPI configuration parameter to 55MHz, and change it to 99MHz after the system boots.

I searched all QuadSPIx_xxx registers, but could not find any setting items for the serial clock frequency.

How do I change the serial clock frequency?

Best Regards,

Takashi Kojima

[takashi_kojima]

Hi, igor,
Thank you for your reply!

I understand that you can change serial clock frequency using Clock Root Table (QSPI_CLK_ROOT).

Best regards,
Takashi Kojima

[igorpadykov · Accepted solution]

Hi Takashi

qspi clock generation is described in Figure 10-16. Flash Clock Diagram,

where ser_clk_4x is the serial clock root from CCM.

i.MX 7Dual Applications Processor Reference Manual

So it can be changed using CCM Table 5-11. Clock Root Table (QSPI_CLK_ROOT),

During boot with Table 6-50. QuadSPI configuration parameters, parameter "Serial Clock
Frequency".

Best regards
igor
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