profile-low.S 1.59 KB
###############################################################################
#
# Fast profiling interrupt handler
#
# Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
# Written by David Howells (dhowells@redhat.com)
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public Licence
# as published by the Free Software Foundation; either version
# 2 of the Licence, or (at your option) any later version.
#
###############################################################################
#include <linux/sys.h>
#include <linux/linkage.h>
#include <asm/segment.h>
#include <asm/smp.h>
#include <asm/intctl-regs.h>
#include <asm/timer-regs.h>

#define pi break

	.balign	4
counter:
	.long	-1

###############################################################################
#
# Profiling interrupt entry point
# - intended to run at interrupt priority 1
#
###############################################################################
ENTRY(profile_handler)
	movm	[d2,d3,a2],(sp)

	# ignore userspace
	mov	(12,sp),d2
	and	EPSW_nSL,d2
	bne	out

	# do nothing if there's no buffer
	mov	(prof_buffer),a2
	and	a2,a2
	beq	out
	or	0x20000000,a2

	# calculate relative position in text segment
	mov	(16,sp),d2
	sub	_stext,d2
	mov	(prof_shift),d3
	lsr	d3,d2
	mov	(prof_len),d3
	cmp	d3,d2
	bcc	outside_text

	# increment the appropriate profile bucket
do_inc:
	asl2	d2
	mov	(a2,d2),d3
	inc	d3
	mov	d3,(a2,d2)
out:
	mov	GxICR_DETECT,d2
	movbu	d2,(TM11ICR)		# ACK the interrupt
	movbu	(TM11ICR),d2
	movm	(sp),[d2,d3,a2]
	rti

outside_text:
	sub	1,d3
	mov	d3,d2
	bra	do_inc