Using the serial port with kernel_old=1 - Raspberry Pi Forums

hi guys,
following on trying make own bare metal examples on rpi 2.
boot kernel_old=1 in order understand steps bring system up.

programs run fine serial output screwed; tried both pl011 , mini uart , both behave same way.
code has been proved work kernel_old=0.

appreciated.
thanks

config.txt bare simple

code: select all

kernel_old=1 disable_commandline_tags=1 

, use simple bootstrap.s jump code

code: select all

.globl _start _start:  	mov	sp, #0x8000		// sp_hyp = 0x18000  	bl	_main halt:	b	halt 

it 4 cpu cores of rpi 2 running same code in program. start @ 0x0 kernel_old=1 , have use mpidr system control register identify them , give them different task or send unneeded cores sleep.

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