How to modify the mdk of sdk?

[junpu]

I am using QSPI of nRF52480 with freqency 2M Hz. Now I want to reduce to 1M Hz, 

but  QSPI_CONFIG_FREQUENCY  min value is 15

// <o> QSPI_CONFIG_FREQUENCY - Frequency divider.

// <0=> 32MHz/1
// <1=> 32MHz/2
// <2=> 32MHz/3
// <3=> 32MHz/4
// <4=> 32MHz/5
// <5=> 32MHz/6
// <6=> 32MHz/7
// <7=> 32MHz/8
// <8=> 32MHz/9
// <9=> 32MHz/10
// <10=> 32MHz/11
// <11=> 32MHz/12
// <12=> 32MHz/13
// <13=> 32MHz/14
// <14=> 32MHz/15
// <15=> 32MHz/16

#ifndef QSPI_CONFIG_FREQUENCY
#define QSPI_CONFIG_FREQUENCY 15
#endif

I see QSPI_IFCONFIG1_SCKFREQ_Msk  is 0xFUL ，so QSPI_CONFIG_FREQUENCY  min value is 15.

I want modify QSPI_IFCONFIG1_SCKFREQ_Msk  how to valid the modify of  QSPI_IFCONFIG1_SCKFREQ_Msk  ?????

/* Bits 31..28 : SCK frequency is given as 32 MHz / (SCKFREQ + 1). */
#define QSPI_IFCONFIG1_SCKFREQ_Pos (28UL) /*!< Position of SCKFREQ field. */
#define QSPI_IFCONFIG1_SCKFREQ_Msk (0xFUL << QSPI_IFCONFIG1_SCKFREQ_Pos) /*!< Bit mask of SCKFREQ field. */

[awneil]

How to properly post source code:

[ovrebekk]

Hi 

This is a limitation in the QSPI hardware module, it is not something you can change in software. 

If you look at the IFCONFIG1 specification in the data sheet you will see that the SCKFREQ field is limited to values in the 0-15 range. 

Is there any particular reason you can't run the QSPI at 2MHz?

Best regards
Torbjørn