1###############################################################################
2#
3# Fast profiling interrupt handler
4#
5# Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
6# Written by David Howells (dhowells@redhat.com)
7#
8# This program is free software; you can redistribute it and/or
9# modify it under the terms of the GNU General Public Licence
10# as published by the Free Software Foundation; either version
11# 2 of the Licence, or (at your option) any later version.
12#
13###############################################################################
14#include <linux/sys.h>
15#include <linux/linkage.h>
16#include <asm/segment.h>
17#include <asm/smp.h>
18#include <asm/intctl-regs.h>
19#include <asm/timer-regs.h>
20
21#define pi break
22
23	.balign	4
24counter:
25	.long	-1
26
27###############################################################################
28#
29# Profiling interrupt entry point
30# - intended to run at interrupt priority 1
31#
32###############################################################################
33ENTRY(profile_handler)
34	movm	[d2,d3,a2],(sp)
35
36	# ignore userspace
37	mov	(12,sp),d2
38	and	EPSW_nSL,d2
39	bne	out
40
41	# do nothing if there's no buffer
42	mov	(prof_buffer),a2
43	and	a2,a2
44	beq	out
45	or	0x20000000,a2
46
47	# calculate relative position in text segment
48	mov	(16,sp),d2
49	sub	_stext,d2
50	mov	(prof_shift),d3
51	lsr	d3,d2
52	mov	(prof_len),d3
53	cmp	d3,d2
54	bcc	outside_text
55
56	# increment the appropriate profile bucket
57do_inc:
58	asl2	d2
59	mov	(a2,d2),d3
60	inc	d3
61	mov	d3,(a2,d2)
62out:
63	mov	GxICR_DETECT,d2
64	movbu	d2,(TM11ICR)		# ACK the interrupt
65	movbu	(TM11ICR),d2
66	movm	(sp),[d2,d3,a2]
67	rti
68
69outside_text:
70	sub	1,d3
71	mov	d3,d2
72	bra	do_inc
73