kernel enable mmu

[lifusong]

Dear sir.

  our board use imx6qsabresd  and bsp is 4.4.3_r1

when boot into kernel and enable mmu ,will case our board lose power

ENTRY(__turn_mmu_on)

  b __error_Debug  //board will lose power after show this debug info.can't see the next debug info.

  mov r0, r0

  instr_sync

  mcr p15, 0, r0, c1, c0, 0 @ write control reg

  mrc p15, 0, r3, c0, c0, 0 @ read id reg

  instr_sync

  mov r3, r3

  mov r3, r13

  mov pc, r3

  b __error_Debug

__turn_mmu_on_end:

ENDPROC(__turn_mmu_on)

  .popsection

who can help me ? thanks.

[lifusong]

sorry,  the board lose power not case by enable mmu

if i add below to start_kernel end

while(1){};

the board not shutdown .but can't see any printk output info.

can see putstr output info.

why?

[igorpadykov]

Hi li

to better understand problem you can try to run minimal image or just SDK

i.MX 6Series Platform SDK : Bare-metal SDK

also it may be recommended to check

Chapter 8 Avoiding Board Bring-up Problems IMX6DQ6SDLHDG

Best regards

igor

-----------------------------------------------------------------------------------------------------------------------

Note: If this post answers your question, please click the Correct Answer button. Thank you!

-----------------------------------------------------------------------------------------------------------------------

[lifusong]

hi igo.

thanks for your reply, I had found this issue.

there is the pmic ,our board use da9063,different with demobaord  so run to start_kernel ->timer_init ,will case lose power.