Stan Yong wrote:
i'm thinking of modifying the FRAP register value in order to enable write and read permission to all the region.
(I don't like giving discouraging information. I have given much.)
I am afraid that it could not be done if datasheet is correct.
As you may have read in the datasheet, FRAP in the chipset is a shadowing register, it is read-only. The original data is in region 0(flash descriptor) of the flash chip, being read during chipset initialization. Since region 0 is also write-protected, flashrom cannot change it. That is a cycle.
How to exactly use flashrom to bring the SPI into descriptor mode so that i can do a read and write to FRAP?
I have some words here because I think you might misunderstand something.
The SPI controller sets itself in descriptor mode when it sees some mark in the flash chip during initialization. It does not need flashrom to bring it into d-mode. And as a memory-mapped register, FRAP can be read regardless of the mode it is in.
yu ning