xref: /openbmc/linux/arch/x86/include/uapi/asm/mtrr.h (revision a2818ee4)
1 /* SPDX-License-Identifier: LGPL-2.0+ WITH Linux-syscall-note */
2 /*  Generic MTRR (Memory Type Range Register) ioctls.
3 
4     Copyright (C) 1997-1999  Richard Gooch
5 
6     This library is free software; you can redistribute it and/or
7     modify it under the terms of the GNU Library General Public
8     License as published by the Free Software Foundation; either
9     version 2 of the License, or (at your option) any later version.
10 
11     This library is distributed in the hope that it will be useful,
12     but WITHOUT ANY WARRANTY; without even the implied warranty of
13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14     Library General Public License for more details.
15 
16     You should have received a copy of the GNU Library General Public
17     License along with this library; if not, write to the Free
18     Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 
20     Richard Gooch may be reached by email at  rgooch@atnf.csiro.au
21     The postal address is:
22       Richard Gooch, c/o ATNF, P. O. Box 76, Epping, N.S.W., 2121, Australia.
23 */
24 #ifndef _UAPI_ASM_X86_MTRR_H
25 #define _UAPI_ASM_X86_MTRR_H
26 
27 #include <linux/types.h>
28 #include <linux/ioctl.h>
29 #include <linux/errno.h>
30 
31 #define	MTRR_IOCTL_BASE	'M'
32 
33 /* Warning: this structure has a different order from i386
34    on x86-64. The 32bit emulation code takes care of that.
35    But you need to use this for 64bit, otherwise your X server
36    will break. */
37 
38 #ifdef __i386__
39 struct mtrr_sentry {
40     unsigned long base;    /*  Base address     */
41     unsigned int size;    /*  Size of region   */
42     unsigned int type;     /*  Type of region   */
43 };
44 
45 struct mtrr_gentry {
46     unsigned int regnum;   /*  Register number  */
47     unsigned long base;    /*  Base address     */
48     unsigned int size;    /*  Size of region   */
49     unsigned int type;     /*  Type of region   */
50 };
51 
52 #else /* __i386__ */
53 
54 struct mtrr_sentry {
55 	__u64 base;		/*  Base address     */
56 	__u32 size;		/*  Size of region   */
57 	__u32 type;		/*  Type of region   */
58 };
59 
60 struct mtrr_gentry {
61 	__u64 base;		/*  Base address     */
62 	__u32 size;		/*  Size of region   */
63 	__u32 regnum;		/*  Register number  */
64 	__u32 type;		/*  Type of region   */
65 	__u32 _pad;		/*  Unused	     */
66 };
67 
68 #endif /* !__i386__ */
69 
70 struct mtrr_var_range {
71 	__u32 base_lo;
72 	__u32 base_hi;
73 	__u32 mask_lo;
74 	__u32 mask_hi;
75 };
76 
77 /* In the Intel processor's MTRR interface, the MTRR type is always held in
78    an 8 bit field: */
79 typedef __u8 mtrr_type;
80 
81 #define MTRR_NUM_FIXED_RANGES 88
82 #define MTRR_MAX_VAR_RANGES 256
83 
84 struct mtrr_state_type {
85 	struct mtrr_var_range var_ranges[MTRR_MAX_VAR_RANGES];
86 	mtrr_type fixed_ranges[MTRR_NUM_FIXED_RANGES];
87 	unsigned char enabled;
88 	unsigned char have_fixed;
89 	mtrr_type def_type;
90 };
91 
92 #define MTRRphysBase_MSR(reg) (0x200 + 2 * (reg))
93 #define MTRRphysMask_MSR(reg) (0x200 + 2 * (reg) + 1)
94 
95 /*  These are the various ioctls  */
96 #define MTRRIOC_ADD_ENTRY        _IOW(MTRR_IOCTL_BASE,  0, struct mtrr_sentry)
97 #define MTRRIOC_SET_ENTRY        _IOW(MTRR_IOCTL_BASE,  1, struct mtrr_sentry)
98 #define MTRRIOC_DEL_ENTRY        _IOW(MTRR_IOCTL_BASE,  2, struct mtrr_sentry)
99 #define MTRRIOC_GET_ENTRY        _IOWR(MTRR_IOCTL_BASE, 3, struct mtrr_gentry)
100 #define MTRRIOC_KILL_ENTRY       _IOW(MTRR_IOCTL_BASE,  4, struct mtrr_sentry)
101 #define MTRRIOC_ADD_PAGE_ENTRY   _IOW(MTRR_IOCTL_BASE,  5, struct mtrr_sentry)
102 #define MTRRIOC_SET_PAGE_ENTRY   _IOW(MTRR_IOCTL_BASE,  6, struct mtrr_sentry)
103 #define MTRRIOC_DEL_PAGE_ENTRY   _IOW(MTRR_IOCTL_BASE,  7, struct mtrr_sentry)
104 #define MTRRIOC_GET_PAGE_ENTRY   _IOWR(MTRR_IOCTL_BASE, 8, struct mtrr_gentry)
105 #define MTRRIOC_KILL_PAGE_ENTRY  _IOW(MTRR_IOCTL_BASE,  9, struct mtrr_sentry)
106 
107 /* MTRR memory types, which are defined in SDM */
108 #define MTRR_TYPE_UNCACHABLE 0
109 #define MTRR_TYPE_WRCOMB     1
110 /*#define MTRR_TYPE_         2*/
111 /*#define MTRR_TYPE_         3*/
112 #define MTRR_TYPE_WRTHROUGH  4
113 #define MTRR_TYPE_WRPROT     5
114 #define MTRR_TYPE_WRBACK     6
115 #define MTRR_NUM_TYPES       7
116 
117 /*
118  * Invalid MTRR memory type.  mtrr_type_lookup() returns this value when
119  * MTRRs are disabled.  Note, this value is allocated from the reserved
120  * values (0x7-0xff) of the MTRR memory types.
121  */
122 #define MTRR_TYPE_INVALID    0xff
123 
124 #endif /* _UAPI_ASM_X86_MTRR_H */
125