callout_power_920.s

QNX ADS BSP code for i.MX27 chips

#
 # $QNXLicenseC: 
 # Copyright 2007, QNX Software Systems.  
 # 
 # Licensed under the Apache License, Version 2.0 (the "License"). You  
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 # WITHOUT WARRANTIES OF ANY KIND, either express or implied. 
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/*
 * ARM920T power callout, also usable for ARM1020T.
 */

#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_920, 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_920)