imx8m plus fuse

[james_wu1]

hi support team

I try to burn MAC address in boot Fusemap (address 0x640 MAC_0_ADDR) on i.MX8m plus 

suppose my mac address is aabbccddeeff

my setting command is:

u-boot=> fuse prog -y 9 0 0xeeff

u-boot=> fuse prog -y 9 1 0xaabbccdd

but  I read back incorrect value. as below. 

Word 0x00000000: ffdfbfaf
u-boot=> fuse read 9 1
Reading bank 9:

Word 0x00000001: 072fffff

Then system use random MAC address.

thank you for help.

James

[khang_letruong]

Dear @james_wu1 ,

I have similar attention to fuse the MAC address of my MX8MP based custom board using u-Boot. Could you please let me know where to find the bank number as well as the words' order, please.

Thanks very much,
Khang

[igorpadykov]

Hi James

what uboot version used in the case, one can try latest

https://source.codeaurora.org/external/imx/uboot-imx/tree/?h=imx_v2020.04_5.4.70_2.3.0

or  Demo Image   i.MX 8M Plus EVK

Best regards
igor

[james_wu1]

hi Igor

Thank you for your answer

my u-boot version

U-Boot 2020.04-gb2c7f94-dirty (May 04 2021 - 13:33:09 +0800)
aarch64-linux-gnu-gcc (GNU Toolchain for the A-profile Architecture 8.3-2019.03(arm-rel-8.36)) 8.3.0
GNU ld (GNU Toolchain for the A-profile Architecture 8.3-2019.03 (arm-rel-8.36)) 2.32.0.20190321

if  "fuse prog" command success is it possible refuse again? or only one time can "fuse prog" ?

for example: If we program incorrect MAC address, how to fuse prog again. (erase the mac area  (address 0x640 MAC_0_ADDR) ...) the fuse prog a correct MAC address.

Another question: How to register a LVDS panel brightnessSupport to imx8mp android10 system?

Our LVDS panel able to display but SurfaceControl.getDisplayBrightnessSupport return false

in frameworks\base\services\core\java\com\android\server\lights\LightsService.java 

so can not control the panel brightness.

Best regards

James

[igorpadykov · Accepted solution]

>if "fuse prog" command success is it possible refuse again? or only one time can "fuse prog" ?

it is one time programmable, so can not be changed after programming. Also may be useful

https://community.nxp.com/t5/i-MX-Processors/OCOTP-write-support-on-i-mx8m/m-p/825028

Best regards
igor