topic How to relocate/execute a function to DDR. in MCUXpresso General

How to relocate/execute a function to DDR.

tandinh — Thu, 27 Dec 2018 13:11:19 GMT

I based on the link: https://community.nxp.com/servlet/JiveServlet/download/104433-4-291307/Relocating+Code+and+Data+Using+the+KDS+GCC+Linker… and was able to relocate a function to the external DDR (0xa000_0000). I verified the relocated function was copied to the DDR and was able to single step to the function. However, as soon as I stepped to the first instruction "a4000000: push {r7, lr}", it led to the HardFault handler. Please help and let me know what am I missing.

I include the KDS example project in the attachment.

Thanks

Re: How to relocate/execute a function to DDR.

Carlos_Mendoza — Mon, 14 Jan 2019 14:59:14 GMT

Hi TAN DINH,

Make sure to initialize the external memory controller before trying to access the DDR memory.

Hope it helps!

Best Regards,
Carlos Mendoza
Technical Support Engineer

Re: How to relocate/execute a function to DDR.

tandinh — Mon, 14 Jan 2019 15:27:07 GMT

Hi Carlos,

Thanks for the reply. I did initialize the DDR before copying. I did find the solution for this. Instead of using physical address of DDR (0xA000_0000), I use the DDR_ALIAS address for code (0x1800_0000), then the issue goes away. I am able to step inside the function in DDR without any issue.

Thanks.

-- Tan Dinh