allwinner/common/arisc_off.S

6 # OpenRISC assembly to turn off an ARM core on an Allwinner SoC from
18 # very ARM core to be turned off.
19 # It expects the core number presented as a mask in the upper half of
25 # - Loop until the core in question reaches WFI.
26 # - Using that mask, activate the core output clamps by setting the
27 #   respective core bit in CPUX_PWROFF_GATING_REG (0x1f01500).
28 #   Note that the clamp for core 0 covers more than just the core, activating
29 #   it hangs the whole system. So we skip this step for core 0.
30 # - Using the negated mask, assert the core's reset line by clearing the
58 	l.bf	1f				# don't touch the bit for core 0
60 	l.lwz	r5, 0x1500(r13)			# core output clamps
62 	l.sw	0x1500(r13), r5			# ... activate for our core
65 	l.xori	r6, r6, -1			# negate core mask
67 	l.sw	0x1c30(r13), r5			# ... assert for our core
69 	l.ff1	r6, r3				# get core number from high mask
71 	l.slli	r6, r6, 2			# r5: core number*4 (0-12)
74 	l.sw	0x1540(r6), r5			# core power switch registers
83 	l.movhi	r3, 0				# FIXUP! with core mask
88 	l.and	r5, r5, r3			# mask requested core
93 	l.sfeqi	r6, 1				# core 0 is special