use xip and norflash initialise make the program run slow

[wangfan_1987]

I encountered a strage problem with the norflash write read.

1. I have vertified a program run in norflash with XIP mode,it can process incomming usart data efficiently.
2. I want to use part of the norflash to save some data,such like baudrate configiration,which only will be write and read during the system start up.I a the example in "MIMIX1176\SDK_2_12_0_MIMXRT1170-EVK\boards\evkmimxrt1170\driver_examples\flexspi\nor\polling_transfer\cm7".I have located the flexspi_nor_flash_ops and fsl_flexspi in ITCM,and it can write and read the norflash normally.
3. When I merged the two programs,the norflash write and read still work normally.But It can not process incoming usart data efficently.The data queue continue full,seems like the program do not run fast enough.
4. When I commnet out the function including flexspi_nor_flash_init(EXAMPLE_FLEXSPI) and flexspi_nor_enable_quad_mode(EXAMPLE_FLEXSPI),the program run fast as it used to be.

Is there someting changed the XIP configuration during the flexspi_nor_flash_init() and flexspi_nor_enable_quad_mode()?Or there is another possible?

[jingpan · Accepted solution]

Hi @wangfan_1987 ,

You can check the clock.

Regards,

Jing

[wangfan_1987]

Thanks for your reply!

When comment out the line flexspi_clock_init() in the function void flexspi_nor_flash_init(FLEXSPI_Type *base), the speed of the program seems work normally.