Hello,
I would to like to know about the boot fuses in TK1 processor.
From the link “Tegra Boot Flow”, I can see that the “The boot ROM determines which device to boot from, by reading a combination of fuses and/or straps”
And I can find the information about strap pins in document “TegraK1_Embedded_DG_v03.pdf”. But I cannot find any information regarding fuses. Any document/information regarding these fuses would be helpful.
Thanks
Tegra devices contain multiple fuses that control different items for security and boot.
OEM Security mode : this must be programmed last to hide the settings and active the fuse
ARM debug disable : disable the JTAG function
Skip Device selection and Straps: determines if boot device is selected from fuses or I/O straps
Boot Key and Device Key : 128bit and 32bit key for secure function, this could be different on every chip.
Boot Device Selection and Boot Device configuration: to determines the boot device and config
Fuses can only be programmed when the fuse programming voltage VPP_FUSE is supplied.
Fuse programming could be done in boot loader during the first time of firmware download.
Program fuses Start → Turn on VPP_Fuse to 1.8v → Call Fuse program API → Turn off VPP_Fuse → Program fuses complete
There is no way to do anything under recovery mode if you forget the Boot Key and Device Key after fuse programmed.
Thanks for your detailed explanation. But, is there any specific document which will provide these details?