setup code

[horseriver]

hi 

  I am confused on booting from grub's rescue mode .

  As we know ,before the kernel start ,the setup code, which is from setup.S 
,will be  executed at front.
  If boot from rescue mode , will grub also load setup code and execute it ? or 
grub execute its own code doing 
  the same work as setup ? then jump to kernel-start directly?

thanks!