callout_power_cp15_wfi.s

Centrality Atlas II development software

#
# Copyright 2007, 2008, QNX Software Systems. 
# 
# Licensed under the Apache License, Version 2.0 (the "License"). You 
# may not reproduce, modify or distribute this software except in 
# compliance with the License. You may obtain a copy of the License 
# at: http://www.apache.org/licenses/LICENSE-2.0 
# 
# Unless required by applicable law or agreed to in writing, software 
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# WITHOUT WARRANTIES OF ANY KIND, either express or implied.
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# This file may contain contributions from others, either as 
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# Please review this entire file for other proprietary rights or license 
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#
#include "callout.ah"

/*
 * --------------------------------------------------------------------------
 * Use the CP15 register 7 "Wait for Interrupt" to halt the processor.
 *
 * On entry:
 *	r0 - pointer to syspage_entry
 *	r1 - flag (currently always 0)
 *
 * FIXME: currently, this callout is only called from the ARM specific halt()
 *        function in the kernel. If this becomes used for a general purpose
 *        power management facility, we will need to handle arguments.
 * --------------------------------------------------------------------------
 */
CALLOUT_START(power_cp15_wfi, 0, 0)

	teq	r1, #0
	bne	1f
	
	mcr	p15, 0, r1, c7, c0, 4			// r1 is 0
	
1:
	mov		r0, #0
	mov	pc, lr

CALLOUT_END(power_cp15_wfi)