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Gokulraj's avatar
Gokulraj
Icon for New Contributor rankNew Contributor
1 year ago

How to access the 8GB ram of DDR in Agilex 7

Hi, I need to access 8GB DDR ram in agilex dev kit,but now i able to access only 2GB ram.While trying to access the remaining 6GB of ram ot throw error as "TFTP error: trying to overwrite reserve...
Arm Processor
Sw Development
tehjingy_Altera's avatar
tehjingy_Altera
Icon for Regular Contributor rankRegular Contributor
1 year ago

Hi


It seems like the uboot device tree was not update to map the whole 8Gb of the DRAM that you have installed.


Could you share your device tree in the forum?

I believe you could try changing the memory node to the follow:

(arch/arm/dts/socfpga_agilex7m_socdk-u-boot.dtsi)

reg = <0 0x00000000 0 0x80000000>,

<0x10 0x80000000 0x1 0x60000000>;


This should include the remaining 6 GB of your device.

Then once booted you could try accessing the address from 0x10 8000 0000 to 0x11 E000 0000


Regards

Jingyang, Teh


  • Gokulraj's avatar
    Gokulraj
    Icon for New Contributor rankNew Contributor
    1 year ago

    Hi,

    Even after changing the device tree as you mentioned above.Same error occurs.

    Here in the u-boot dts file what ever the memory [1] region,it mapped as reserved area.

    Please take a look at the bdinfo log of updated device tree log.

    bdinfo log

    "

    lmb_dump_all:
    memory.cnt = 0x2 / max = 0x10
    memory[0] [0x0-0x7fffffff], 0x80000000 bytes flags: 0 ( 2GB )

    memory[1] [0x1080000000-0x11dfffffff], 0x160000000 bytes flags: 0

    reserved.cnt = 0x4 / max = 0x10
    reserved[0] [0x0-0x1ffffff], 0x02000000 bytes flags: 4
    reserved[1] [0x7eb08000-0x7fffffff], 0x014f8000 bytes flags: 0

    reserved[2] [0x1080000000-0x11dfffffff], 0x160000000 bytes flags: 0

    "

    I believe the issue is not memory mapping node,it is reserved area mapping.

    For your information,I am using Agilex 7soc not Agilex 7m and I have shared the default .dts file for your reference.

    Thanks,

    M Gokulraj