RT1170 flexSPI XiP max serial clock

[nickwallis]

Hi,

I want to check, please can you tell me all the settings we need to change to make the SDK projects run at maximum QSPI serial clock frequency for XiP applications?

We already made sure to float the DQS pin in our schematics (GPIO_SD_B2_05).

We also made sure in evkmimxrt1060_flexspi_nor_config.c that readSampleClkSrc is set to kFlexSPIReadSampleClk_LoopbackFromDqsPad;

What other settings are needed to ensure max speed operation from external QSPI flash (133 MHz)?

Our external QSPI flash is MX25U12832FM2I02.

many thanks!

[nickwallis]

@jingpan thanks, but I meant from a software point of view (apologies this wasn't clear).

In the SDK, which setting(s) have to be changed in which source module(s) to ensure maximum QSPI serial clock frequency operation?

thanks!

[jingpan]

Hi @nickwallis ,

What you have done is enough. Next step, just configure the input clock to 133Mhz.

Or if you didn't change the qspflash_config, serialClkFreq is kFlexSpiSerialClk_133MHz already. That means ROM boot will set the flexspi frequency to 133Mhz before jump to your application. So, you needn't do anything.

Regards,

Jing

[jingpan]

Hi @nickwallis ,

That's fine. Please also refer to hardware design guide about flexspi layout recommendation.

Regards,

Jing