summaryrefslogtreecommitdiffstats
path: root/sys/mips/include/pte.h
blob: c798eeef5124c604888101e5a7361a834a84c0cc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
/*-
 * Copyright (c) 2004-2010 Juli Mallett <jmallett@FreeBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD$
 */

#ifndef	_MACHINE_PTE_H_
#define	_MACHINE_PTE_H_

#ifndef _LOCORE
#if defined(__mips_n64) || defined(__mips_n32) /*  PHYSADDR_64_BIT */
typedef	uint64_t pt_entry_t;
#else
typedef	uint32_t pt_entry_t;
#endif
typedef	pt_entry_t *pd_entry_t;
#endif

/*
 * TLB and PTE management.  Most things operate within the context of
 * EntryLo0,1, and begin with TLBLO_.  Things which work with EntryHi
 * start with TLBHI_.  PTE bits begin with PTE_.
 *
 * Note that we use the same size VM and TLB pages.
 */
#define	TLB_PAGE_SHIFT	(PAGE_SHIFT)
#define	TLB_PAGE_SIZE	(1 << TLB_PAGE_SHIFT)
#define	TLB_PAGE_MASK	(TLB_PAGE_SIZE - 1)

/*
 * TLB PageMask register.  Has mask bits set above the default, 4K, page mask.
 */
#define	TLBMASK_SHIFT	(13)
#define	TLBMASK_MASK	((PAGE_MASK >> TLBMASK_SHIFT) << TLBMASK_SHIFT)

/*
 * PFN for EntryLo register.  Upper bits are 0, which is to say that
 * bit 28 is the last hardware bit;  Bits 29 and upwards (EntryLo is
 * 64 bit though it can be referred to in 32-bits providing 3 software
 * bits safely.  We use it as 64 bits to get many software bits, and
 * god knows what else.) are unacknowledged by hardware.  They may be
 * written as anything, but otherwise they have as much meaning as
 * other 0 fields.
 */
#if defined(__mips_n64) || defined(__mips_n32) /*  PHYSADDR_64_BIT */
#define	TLBLO_SWBITS_SHIFT	(34)
#define	TLBLO_PFN_MASK		0x3FFFFFFC0ULL
#else
#define	TLBLO_SWBITS_SHIFT	(29)
#define	TLBLO_PFN_MASK		(0x1FFFFFC0)
#endif
#define	TLBLO_PFN_SHIFT		(6)
#define	TLBLO_SWBITS_MASK	((pt_entry_t)0x7 << TLBLO_SWBITS_SHIFT)
#define	TLBLO_PA_TO_PFN(pa)	((((pa) >> TLB_PAGE_SHIFT) << TLBLO_PFN_SHIFT) & TLBLO_PFN_MASK)
#define	TLBLO_PFN_TO_PA(pfn)	((vm_paddr_t)((pfn) >> TLBLO_PFN_SHIFT) << TLB_PAGE_SHIFT)
#define	TLBLO_PTE_TO_PFN(pte)	((pte) & TLBLO_PFN_MASK)
#define	TLBLO_PTE_TO_PA(pte)	(TLBLO_PFN_TO_PA(TLBLO_PTE_TO_PFN((pte))))

/*
 * XXX This comment is not correct for anything more modern than R4K.
 *
 * VPN for EntryHi register.  Upper two bits select user, supervisor,
 * or kernel.  Bits 61 to 40 copy bit 63.  VPN2 is bits 39 and down to
 * as low as 13, down to PAGE_SHIFT, to index 2 TLB pages*.  From bit 12
 * to bit 8 there is a 5-bit 0 field.  Low byte is ASID.
 *
 * XXX This comment is not correct for FreeBSD.
 * Note that in FreeBSD, we map 2 TLB pages is equal to 1 VM page.
 */
#define	TLBHI_ASID_MASK		(0xff)
#if defined(__mips_n64)
#define	TLBHI_R_SHIFT		62
#define	TLBHI_R_USER		(0x00UL << TLBHI_R_SHIFT)
#define	TLBHI_R_SUPERVISOR	(0x01UL << TLBHI_R_SHIFT)
#define	TLBHI_R_KERNEL		(0x03UL << TLBHI_R_SHIFT)
#define	TLBHI_R_MASK		(0x03UL << TLBHI_R_SHIFT)
#define	TLBHI_VA_R(va)		((va) & TLBHI_R_MASK)
#define	TLBHI_FILL_SHIFT	40
#define	TLBHI_VPN2_SHIFT	(TLB_PAGE_SHIFT + 1)
#define	TLBHI_VPN2_MASK		(((~((1UL << TLBHI_VPN2_SHIFT) - 1)) << (63 - TLBHI_FILL_SHIFT)) >> (63 - TLBHI_FILL_SHIFT))
#define	TLBHI_VA_TO_VPN2(va)	((va) & TLBHI_VPN2_MASK)
#define	TLBHI_ENTRY(va, asid)	((TLBHI_VA_R((va))) /* Region. */ | \
				 (TLBHI_VA_TO_VPN2((va))) /* VPN2. */ | \
				 ((asid) & TLBHI_ASID_MASK))
#else /* !defined(__mips_n64) */
#define	TLBHI_PAGE_MASK		(2 * PAGE_SIZE - 1)
#define	TLBHI_ENTRY(va, asid)	(((va) & ~TLBHI_PAGE_MASK) | ((asid) & TLBHI_ASID_MASK))
#endif /* defined(__mips_n64) */

/*
 * TLB flags managed in hardware:
 * 	C:	Cache attribute.
 * 	D:	Dirty bit.  This means a page is writable.  It is not
 * 		set at first, and a write is trapped, and the dirty
 * 		bit is set.  See also PTE_RO.
 * 	V:	Valid bit.  Obvious, isn't it?
 * 	G:	Global bit.  This means that this mapping is present
 * 		in EVERY address space, and to ignore the ASID when
 * 		it is matched.
 */
#define	PTE_C(attr)		((attr & 0x07) << 3)
#define	PTE_C_UNCACHED		(PTE_C(MIPS_CCA_UNCACHED))
#define	PTE_C_CACHE		(PTE_C(MIPS_CCA_CACHED))
#define	PTE_D			0x04
#define	PTE_V			0x02
#define	PTE_G			0x01

/*
 * VM flags managed in software:
 * 	RO:	Read only.  Never set PTE_D on this page, and don't
 * 		listen to requests to write to it.
 * 	W:	Wired.  ???
 *	MANAGED:Managed.  This PTE maps a managed page.
 */
#define	PTE_RO			((pt_entry_t)0x01 << TLBLO_SWBITS_SHIFT)
#define	PTE_W			((pt_entry_t)0x02 << TLBLO_SWBITS_SHIFT)
#define	PTE_MANAGED		((pt_entry_t)0x04 << TLBLO_SWBITS_SHIFT)

/*
 * PTE management functions for bits defined above.
 */
#define	pte_clear(pte, bit)	(*(pte) &= ~(bit))
#define	pte_set(pte, bit)	(*(pte) |= (bit))
#define	pte_test(pte, bit)	((*(pte) & (bit)) == (bit))

/* Assembly support for PTE access*/
#ifdef LOCORE
#if defined(__mips_n64) || defined(__mips_n32) /*  PHYSADDR_64_BIT */
#define	PTESHIFT		3
#define	PTE2MASK		0xff0	/* for the 2-page lo0/lo1 */
#define	PTEMASK			0xff8
#define	PTESIZE			8
#define	PTE_L			ld
#define	PTE_MTC0		dmtc0
#define	CLEAR_PTE_SWBITS(pr)
#else
#define	PTESHIFT		2
#define	PTE2MASK		0xff8	/* for the 2-page lo0/lo1 */
#define	PTEMASK			0xffc
#define	PTESIZE			4
#define	PTE_L			lw
#define	PTE_MTC0		mtc0
#define	CLEAR_PTE_SWBITS(r)	sll r, 3; srl r, 3 /* remove 3 high bits */
#endif /* defined(__mips_n64) || defined(__mips_n32) */

#if defined(__mips_n64)
#define	PTRSHIFT		3
#define	PDEPTRMASK		0xff8
#else
#define	PTRSHIFT		2
#define	PDEPTRMASK		0xffc
#endif

#endif /* LOCORE */
#endif /* !_MACHINE_PTE_H_ */
OpenPOWER on IntegriCloud