Now, I am use P1010 cpu in the system. I use normal uboot&linux image booting from nor flash, not secure boot and never touch sfp fuse in P1010.
Sometimes I find that the cpu cannot boot uboot and no uboot print info in the uart console. When I power off and power on it again, it is the same. Then I use codewarrior usb tape to connnet the cpu, but the codewarrior software ask for a 64bit response word, and I also do not known the word.
This problem is cased by hardware or software and maybe where? Can I skip this problem by disble secure boot completely and how?
Please look P1010 Reference Manual, Section 22.214.171.124 "Secure boot configuration"
If "Intent to secure" fuse is not blown, you can pull-up HRESET_REQ_B during reset to disable secure boot.
This pin has internal weak pull-up, however if you have anything connected to this pin (I'm quite sure you do have), than this internal weak pull-up may be not adequate and external pull-up or active driver is required. Please see device datasheet, Table 1, Note 3 below the table.
Both mentioned documents are available for download from P1010 Product Page, "Documentation" tab:
Thanks for your suggestion.
If the cfg_sb_dis is not external pull-up suitably, P1010 may enter secure boot mode. Does the cpu not never enter non-secure boot mode by power up again if pull-up resister is ok? It seams that the cpu is locked by it self and I must replace the cpu. Now i use a 4.7k pull-up resister to 3.3v.