1###############################################################################
2#
3# TLB loading functions
4#
5# Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
6# Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
7# Modified by David Howells (dhowells@redhat.com)
8#
9# This program is free software; you can redistribute it and/or
10# modify it under the terms of the GNU General Public Licence
11# as published by the Free Software Foundation; either version
12# 2 of the Licence, or (at your option) any later version.
13#
14###############################################################################
15#include <linux/sys.h>
16#include <linux/linkage.h>
17#include <asm/smp.h>
18#include <asm/intctl-regs.h>
19#include <asm/frame.inc>
20#include <asm/page.h>
21#include <asm/pgtable.h>
22
23###############################################################################
24#
25# Instruction TLB Miss handler entry point
26#
27###############################################################################
28	.type	itlb_miss,@function
29ENTRY(itlb_miss)
30#ifdef CONFIG_GDBSTUB
31	movm	[d2,d3,a2],(sp)
32#else
33	or	EPSW_nAR,epsw		# switch D0-D3 & A0-A3 to the alternate
34					# register bank
35	nop
36	nop
37	nop
38#endif
39
40#if defined(CONFIG_ERRATUM_NEED_TO_RELOAD_MMUCTR)
41	mov	(MMUCTR),d2
42	mov	d2,(MMUCTR)
43#endif
44
45	and	~EPSW_NMID,epsw
46	mov	(IPTEU),d3
47	mov	(PTBR),a2
48	mov	d3,d2
49	and	0xffc00000,d2
50	lsr	20,d2
51	mov	(a2,d2),a2		# PTD *ptd = PGD[addr 31..22]
52	btst	_PAGE_VALID,a2
53	beq	itlb_miss_fault		# jump if doesn't point anywhere
54
55	and	~(PAGE_SIZE-1),a2
56	mov	d3,d2
57	and	0x003ff000,d2
58	lsr	10,d2
59	add	d2,a2
60	mov	(a2),d2			# get pte from PTD[addr 21..12]
61	btst	_PAGE_VALID,d2
62	beq	itlb_miss_fault		# jump if doesn't point to a page
63					# (might be a swap id)
64#if	((_PAGE_ACCESSED & 0xffffff00) == 0)
65	bset	_PAGE_ACCESSED,(0,a2)
66#elif	((_PAGE_ACCESSED & 0xffff00ff) == 0)
67	bset	+(_PAGE_ACCESSED >> 8),(1,a2)
68#else
69#error	"_PAGE_ACCESSED value is out of range"
70#endif
71	and	~xPTEL2_UNUSED1,d2
72itlb_miss_set:
73	mov	d2,(IPTEL2)		# change the TLB
74#ifdef CONFIG_GDBSTUB
75	movm	(sp),[d2,d3,a2]
76#endif
77	rti
78
79itlb_miss_fault:
80	mov	_PAGE_VALID,d2		# force address error handler to be
81					# invoked
82	bra	itlb_miss_set
83
84	.size	itlb_miss, . - itlb_miss
85
86###############################################################################
87#
88# Data TLB Miss handler entry point
89#
90###############################################################################
91	.type	dtlb_miss,@function
92ENTRY(dtlb_miss)
93#ifdef CONFIG_GDBSTUB
94	movm	[d2,d3,a2],(sp)
95#else
96	or	EPSW_nAR,epsw		# switch D0-D3 & A0-A3 to the alternate
97					# register bank
98	nop
99	nop
100	nop
101#endif
102
103#if defined(CONFIG_ERRATUM_NEED_TO_RELOAD_MMUCTR)
104	mov	(MMUCTR),d2
105	mov	d2,(MMUCTR)
106#endif
107
108	and	~EPSW_NMID,epsw
109	mov	(DPTEU),d3
110	mov	(PTBR),a2
111	mov	d3,d2
112	and	0xffc00000,d2
113	lsr	20,d2
114	mov	(a2,d2),a2		# PTD *ptd = PGD[addr 31..22]
115	btst	_PAGE_VALID,a2
116	beq	dtlb_miss_fault		# jump if doesn't point anywhere
117
118	and	~(PAGE_SIZE-1),a2
119	mov	d3,d2
120	and	0x003ff000,d2
121	lsr	10,d2
122	add	d2,a2
123	mov	(a2),d2			# get pte from PTD[addr 21..12]
124	btst	_PAGE_VALID,d2
125	beq	dtlb_miss_fault		# jump if doesn't point to a page
126					# (might be a swap id)
127#if	((_PAGE_ACCESSED & 0xffffff00) == 0)
128	bset	_PAGE_ACCESSED,(0,a2)
129#elif	((_PAGE_ACCESSED & 0xffff00ff) == 0)
130	bset	+(_PAGE_ACCESSED >> 8),(1,a2)
131#else
132#error	"_PAGE_ACCESSED value is out of range"
133#endif
134	and	~xPTEL2_UNUSED1,d2
135dtlb_miss_set:
136	mov	d2,(DPTEL2)		# change the TLB
137#ifdef CONFIG_GDBSTUB
138	movm	(sp),[d2,d3,a2]
139#endif
140	rti
141
142dtlb_miss_fault:
143	mov	_PAGE_VALID,d2		# force address error handler to be
144					# invoked
145	bra	dtlb_miss_set
146	.size	dtlb_miss, . - dtlb_miss
147
148###############################################################################
149#
150# Instruction TLB Address Error handler entry point
151#
152###############################################################################
153	.type	itlb_aerror,@function
154ENTRY(itlb_aerror)
155	add	-4,sp
156	SAVE_ALL
157
158#if defined(CONFIG_ERRATUM_NEED_TO_RELOAD_MMUCTR)
159	mov	(MMUCTR),d1
160	mov	d1,(MMUCTR)
161#endif
162
163	and	~EPSW_NMID,epsw
164	add	-4,sp				# need to pass three params
165
166	# calculate the fault code
167	movhu	(MMUFCR_IFC),d1
168	or	0x00010000,d1			# it's an instruction fetch
169
170	# determine the page address
171	mov	(IPTEU),d0
172	and	PAGE_MASK,d0
173	mov	d0,(12,sp)
174
175	clr	d0
176	mov	d0,(IPTEL2)
177
178	or	EPSW_IE,epsw
179	mov	fp,d0
180	call	do_page_fault[],0		# do_page_fault(regs,code,addr
181
182	jmp	ret_from_exception
183	.size	itlb_aerror, . - itlb_aerror
184
185###############################################################################
186#
187# Data TLB Address Error handler entry point
188#
189###############################################################################
190	.type	dtlb_aerror,@function
191ENTRY(dtlb_aerror)
192	add	-4,sp
193	SAVE_ALL
194
195#if defined(CONFIG_ERRATUM_NEED_TO_RELOAD_MMUCTR)
196	mov	(MMUCTR),d1
197	mov	d1,(MMUCTR)
198#endif
199
200	add	-4,sp				# need to pass three params
201	and	~EPSW_NMID,epsw
202
203	# calculate the fault code
204	movhu	(MMUFCR_DFC),d1
205
206	# determine the page address
207	mov	(DPTEU),a2
208	mov	a2,d0
209	and	PAGE_MASK,d0
210	mov	d0,(12,sp)
211
212	clr	d0
213	mov	d0,(DPTEL2)
214
215	or	EPSW_IE,epsw
216	mov	fp,d0
217	call	do_page_fault[],0		# do_page_fault(regs,code,addr
218
219	jmp	ret_from_exception
220	.size	dtlb_aerror, . - dtlb_aerror
221