linux_kernel/drivers/gpu/drm/nouveau/nvkm/subdev/pmu/fuc/idle.fuc

/*
 * Copyright 2013 Red Hat Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors: Ben Skeggs
 */

#ifdef INCLUDE_PROC
process(PROC_IDLE, #idle, #idle_recv)
#endif

/******************************************************************************
 * IDLE data segment
 *****************************************************************************/
#ifdef INCLUDE_DATA
#endif

/******************************************************************************
 * IDLE code segment
 *****************************************************************************/
#ifdef INCLUDE_CODE
// description
//
// $r15 - current (idle)
// $r14 - message
// $r0  - zero
idle_recv:
	ret

// description
//
// $r15 - current (idle)
// $r0  - zero
idle:
	// set our "no interrupt has occurred during our execution" flag
	bset $flags $p0

	// count IDLE invocations for debugging purposes
	nv_iord($r1, NV_PPWR_DSCRATCH(1))
	add b32 $r1 1
	nv_iowr(NV_PPWR_DSCRATCH(1), $r1)

	// keep looping while there's pending messages for any process
	idle_loop:
	mov $r1 #proc_list_head
	bclr $flags $p2
	idle_proc:
		// process the process' messages until there's none left
		idle_proc_exec:
			push $r1
			mov b32 $r14 $r1
			call(recv)
			pop $r1
			bra not $p1 #idle_proc_next
			bset $flags $p2
			bra #idle_proc_exec
		// next process!
		idle_proc_next:
		add b32 $r1 #proc_size
		cmp b32 $r1 $r15
		bra ne #idle_proc
	bra $p2 #idle_loop

	// sleep if no interrupts have occurred
	sleep $p0
	bra #idle
#endif