Boot sequence of i.MX7D

[ko-hey]

Hi all

My customer would like to reset the system using the WDT timeout reset.

However, they can't success.

In this situation, we have some questions about boot sequence of i.MX7D.

Q1

They don't input to POR at the time of WDT reset.

Do they have to input POR ? 

Q2.

According to the Figure 6-20 in IMX7DRM, there are some branch.

What is the criteria of "Check Reset Type" branch ?

In other word, what do you mean the "Normal" ?

Q3

In the "Download Initial boot Image(primary or secondary depending on persistent bit)" branch, what is the criteria ?

My understanding is only checking a vector table and persistent bit. Am I correct ?

Ko-hey

[joanxie · Accepted solution]

1) refer to the RM:"During reset, the chip checks Power Gating Controller status register." so for the detailed status, pls refer to the PGC, refer to the flow, besides of nomally mode, another is waking up from low power boot mode

2) yes

[ko-hey]

Hi joanxie‌

Thank you for reply.

Let me confirm your answer.

Q4

"Check Reset Type" branch checks the Power Gating Controller status register.

So when user want to waking up from low power boot mode, it will goes to "Is Wakeup allowed" branch.

Am I correct ?

Do you have any example of PGC register when user do WDT reset ?

Q5

The answer of 2) is for Q3. Am I correct ?

Ko-hey

[joanxie]

yes, right for two questions, sorry, we don't have such example for this.

[ko-hey]

Hi joanxie‌

Thank you for reply.

I understand !

Ko-hey