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
|
/*=======================================================================================*/
/* RISCV Sail Model */
/* */
/* This Sail RISC-V architecture model, comprising all files and */
/* directories except for the snapshots of the Lem and Sail libraries */
/* in the prover_snapshots directory (which include copies of their */
/* licences), is subject to the BSD two-clause licence below. */
/* */
/* Copyright (c) 2017-2023 */
/* Prashanth Mundkur */
/* Rishiyur S. Nikhil and Bluespec, Inc. */
/* Jon French */
/* Brian Campbell */
/* Robert Norton-Wright */
/* Alasdair Armstrong */
/* Thomas Bauereiss */
/* Shaked Flur */
/* Christopher Pulte */
/* Peter Sewell */
/* Alexander Richardson */
/* Hesham Almatary */
/* Jessica Clarke */
/* Microsoft, for contributions by Robert Norton-Wright and Nathaniel Wesley Filardo */
/* Peter Rugg */
/* Aril Computer Corp., for contributions by Scott Johnson */
/* Philipp Tomsich */
/* VRULL GmbH, for contributions by its employees */
/* */
/* All rights reserved. */
/* */
/* This software was developed by the above within the Rigorous */
/* Engineering of Mainstream Systems (REMS) project, partly funded by */
/* EPSRC grant EP/K008528/1, at the Universities of Cambridge and */
/* Edinburgh. */
/* */
/* This software was developed by SRI International and the University of */
/* Cambridge Computer Laboratory (Department of Computer Science and */
/* Technology) under DARPA/AFRL contract FA8650-18-C-7809 ("CIFV"), and */
/* under DARPA contract HR0011-18-C-0016 ("ECATS") as part of the DARPA */
/* SSITH research programme. */
/* */
/* This project has received funding from the European Research Council */
/* (ERC) under the European Union’s Horizon 2020 research and innovation */
/* programme (grant agreement 789108, ELVER). */
/* */
/* */
/* 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. */
/*=======================================================================================*/
/*
* Types used in supporting extensions for page-table walks.
*
* There are three types involved:
*
* . An accumulator, passed down from the root to the leaves (ext_ptw)
* . Metadata returned with failed permissions checks (ext_ptw_fail)
* . Errors embedded within the PTW_Error union
*
* Information flow begins with init_ext_ptw (: ext_ptw) being routed,
* via the translateNN functions and/or walkNN functions, to the
* checkPTEPermission function, which is the intended point of
* interaction with extensions.
*
* checkPTEPermission will be called repeatedly at each PTE, each call
* seeing the accumulator state generated by a successful result of
* the previous call. On failure, this function is expected to
* generate, instead, an ext_ptw_fail value as well as a new
* accumulator value, both of which will be returned to the code
* calling into translation.
*
* If translation ultimately succeeds, the final accumulator state is
* captured and will be returned to the code calling into translation.
*
* If translation ultimately fails, the accumulator at the time of
* failure and the ext_ptw_fail value are returned to the caller. The
* ext_ptw_fail value is used to generate a PTW_Error value by calling
* ext_get_ptw_error; this allows the extension to generate both novel
* (e.g., PTW_Ext_Error) and existing (e.g., PTW_Invalid_PTE) PTW_Error
* values.
*/
type ext_ptw = unit
let init_ext_ptw : ext_ptw = ()
type ext_ptw_fail = unit
/* This type can be used for custom errors for page-table-walks,
* and values in this type are typically generated from the final
* result of the ext_ptw at the end of the walk.
*/
type ext_ptw_error = unit /* No extensions for page-table-walk errors */
/* This type supports extensions to the exceptions defined in the ISA. */
type ext_exc_type = unit /* No exception extensions */
/* Default translation of PTW errors into exception annotations */
function ext_translate_exception(e : ext_ptw_error) -> ext_exc_type =
e /* type pun because both are unit; extensions may need to override this */
/* Default conversion of extension exceptions to bits */
val ext_exc_type_to_bits : ext_exc_type -> exc_code
function ext_exc_type_to_bits(e) = 0x18 /* First code for a custom extension */
/* Default conversion of extension exceptions to integers */
val num_of_ext_exc_type : ext_exc_type -> {'n, (0 <= 'n < xlen). int('n)}
function num_of_ext_exc_type(e) = 24 /* First code for a custom extension */
/* Default conversion of extension exceptions to strings */
val ext_exc_type_to_str : ext_exc_type -> string
function ext_exc_type_to_str(e) = "extension-exception"
|
