Keep same header structure in SRK Table and Record

cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

Keep same header structure in SRK Table and Record

1,630 Views
csoapy
Contributor III

I'm writing code to parse container file. And found that there are 3 similar struct headers used to indicate data block's TAG, SIZE and VERSION:

A: { VERSION, LENGTH_L, LENGHT_H, TAG}

        Used in Container, SignatureBlock, Signature, Certificate, Block(DEK)'s header.

B: {TAG,  LENGTH_L/H, LENGHT_H/L, VERSION}

        Used in SRK Table's header.

C: {Tag, LENGTH_L/H, LENGHT_H/L}

        Used in SRK Record's header

P.S. I use `L/H` because there are labled as `Variable` in a fixed length of 2 bytes in i.MX8 RM Rev.0

This two make me confused:

  1. Why not use same structures?
  2. Why not place TAG to the first byte of a structure?
0 Kudos
8 Replies

1,557 Views
csoapy
Contributor III

Another weird order in Signature Block:

Offset:    {Certi,           SRK Table,  Sign, Blob}

Content: {SRK Table, Sign,            Certi, Blob}

csoapy_0-1600347575965.png

 

 

0 Kudos

1,552 Views
igorpadykov
NXP Employee
NXP Employee

processor ROM structures and definitions are hardcoded at chip design level,

they can not be changed later.

 

Best regards
igor

0 Kudos

1,546 Views
csoapy
Contributor III

processor ROM structures and definitions are hardcoded at chip design level,

they can not be changed later.

Since it's hardcoded, then hardcode them again.

I don't think they can not be changed later.

There're i.MX8 B0 and C0 release. So why can't fix them in D0?

It's about how much works need to be done.

It's not about CAN or CAN NOT.

BAD is BAD. and need to be fixed.

 

0 Kudos

1,614 Views
csoapy
Contributor III

@igorpadykov  Can you delete your reply? It's not an answer to the question.

0 Kudos

1,601 Views
igorpadykov
NXP Employee
NXP Employee

 answer to the questions:

  1. Why not use same structures?
  2. Why not place TAG to the first byte of a structure?
  3.  

A: it is defined in i.MX8 ROM.

 

Best regards
igor

0 Kudos

1,578 Views
csoapy
Contributor III

@igorpadykov  I mean, it's a bad definition, a bad design in another word.

0 Kudos

1,570 Views
igorpadykov
NXP Employee
NXP Employee

>I mean, it's a bad definition, a bad design in another word.

 

sorry processor ROM structures and definitions are hardcoded at chip design level,

they can not be changed later.

 

Best regards
igor

0 Kudos