summaryrefslogtreecommitdiff
path: root/src/arch/riscv/include/vm.h
blob: a30d6bbdd58e1e1c18f2607311344db9c6a34f4b (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
/*
 * Copyright (c) 2013, The Regents of the University of California (Regents).
 * 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.
 * 3. Neither the name of the Regents nor the
 * names of its contributors may be used to endorse or promote products
 * derived from this software without specific prior written permission.
 *
 * IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
 * SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING
 * OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF REGENTS HAS
 * BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE. THE SOFTWARE AND ACCOMPANYING DOCUMENTATION, IF ANY, PROVIDED
 * HEREUNDER IS PROVIDED "AS IS". REGENTS HAS NO OBLIGATION TO PROVIDE
 * MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
 */

#ifndef _VM_H
#define _VM_H

#include <string.h>
#include <stdint.h>
#include <arch/encoding.h>

#define EXTRACT_FIELD(val, which) (((val) & (which)) / ((which) & ~((which)-1)))
#define INSERT_FIELD(val, which, fieldval) (((val) & ~(which)) | ((fieldval) * ((which) & ~((which)-1))))

void mstatus_init(void); // need to setup mstatus so we know we have virtual memory


#define DEFINE_MPRV_READ(name, type, insn)				\
	static inline type name(type *p);				\
	static inline type name(type *p)				\
	{								\
		size_t mprv = MSTATUS_MPRV;				\
		type value;						\
		asm (							\
			"csrs		mstatus, %1\n"			\
			STRINGIFY(insn) " %0, 0(%2)\n"			\
			"csrc		mstatus, %1\n"			\
			: "=&r"(value) : "r"(mprv), "r"(p) : "memory"	\
		);							\
		return value;						\
	}

#define DEFINE_MPRV_WRITE(name, type, insn)				\
	static inline void name(type *p, type value);			\
	static inline void name(type *p, type value)			\
	{								\
		size_t mprv = MSTATUS_MPRV;				\
		asm (							\
			"csrs		mstatus, %0\n"			\
			STRINGIFY(insn) " %1, 0(%2)\n"			\
			"csrc		mstatus, %0\n"			\
			:: "r"(mprv), "r"(value), "r"(p) : "memory"	\
		);							\
	}

/*
 * mprv_{read,write}_* - Modified privilege memory access functions.
 *
 * These inline functions perform a read or write memory operation with the
 * mstatus.MPRV bit set. This causes the memory protections and translation of
 * the previous mode (e.g. U-mode, if we're handling a trap from U-mode) to be
 * applied.
 *
 * The user of these functions must make sure to avoid trap loops through
 * unaligned memory accesses.
 */
DEFINE_MPRV_READ(mprv_read_u8, uint8_t, lbu)
DEFINE_MPRV_READ(mprv_read_u16, uint16_t, lhu)
DEFINE_MPRV_READ(mprv_read_u32, uint32_t, lwu)
DEFINE_MPRV_READ(mprv_read_u64, uint64_t, ld)
DEFINE_MPRV_READ(mprv_read_long, long, ld)
DEFINE_MPRV_READ(mprv_read_ulong, unsigned long, ld)
DEFINE_MPRV_WRITE(mprv_write_u8, uint8_t, sb)
DEFINE_MPRV_WRITE(mprv_write_u16, uint16_t, sh)
DEFINE_MPRV_WRITE(mprv_write_u32, uint32_t, sw)
DEFINE_MPRV_WRITE(mprv_write_u64, uint64_t, sd)
DEFINE_MPRV_WRITE(mprv_write_long, long, sd)
DEFINE_MPRV_WRITE(mprv_write_ulong, unsigned long, sd)

#undef DEFINE_MPRV_READ
#undef DEFINE_MPRV_WRITE


#endif