mtrr.h

  1/* SPDX-License-Identifier: LGPL-2.0+ */
  2/*  Generic MTRR (Memory Type Range Register) ioctls.
  3
  4    Copyright (C) 1997-1999  Richard Gooch
  5
  6    Richard Gooch may be reached by email at  rgooch@atnf.csiro.au
  7    The postal address is:
  8      Richard Gooch, c/o ATNF, P. O. Box 76, Epping, N.S.W., 2121, Australia.
  9*/
 10#ifndef _ASM_X86_MTRR_H
 11#define _ASM_X86_MTRR_H
 12
 13#include <linux/bits.h>
 14#include <uapi/asm/mtrr.h>
 15
 16/* Defines for hardware MTRR registers. */
 17#define MTRR_CAP_VCNT		GENMASK(7, 0)
 18#define MTRR_CAP_FIX		BIT_MASK(8)
 19#define MTRR_CAP_WC		BIT_MASK(10)
 20
 21#define MTRR_DEF_TYPE_TYPE	GENMASK(7, 0)
 22#define MTRR_DEF_TYPE_FE	BIT_MASK(10)
 23#define MTRR_DEF_TYPE_E		BIT_MASK(11)
 24
 25#define MTRR_DEF_TYPE_ENABLE	(MTRR_DEF_TYPE_FE | MTRR_DEF_TYPE_E)
 26#define MTRR_DEF_TYPE_DISABLE	~(MTRR_DEF_TYPE_TYPE | MTRR_DEF_TYPE_ENABLE)
 27
 28#define MTRR_PHYSBASE_TYPE	GENMASK(7, 0)
 29#define MTRR_PHYSBASE_RSVD	GENMASK(11, 8)
 30
 31#define MTRR_PHYSMASK_RSVD	GENMASK(10, 0)
 32#define MTRR_PHYSMASK_V		BIT_MASK(11)
 33
 34struct mtrr_state_type {
 35	struct mtrr_var_range var_ranges[MTRR_MAX_VAR_RANGES];
 36	mtrr_type fixed_ranges[MTRR_NUM_FIXED_RANGES];
 37	unsigned char enabled;
 38	bool have_fixed;
 39	mtrr_type def_type;
 40};
 41
 42/*
 43 * The following functions are for use by other drivers that cannot use
 44 * arch_phys_wc_add and arch_phys_wc_del.
 45 */
 46# ifdef CONFIG_MTRR
 47void mtrr_bp_init(void);
 48void guest_force_mtrr_state(struct mtrr_var_range *var, unsigned int num_var,
 49			    mtrr_type def_type);
 50extern u8 mtrr_type_lookup(u64 addr, u64 end, u8 *uniform);
 51extern void mtrr_save_fixed_ranges(void *);
 52extern void mtrr_save_state(void);
 53extern int mtrr_add(unsigned long base, unsigned long size,
 54		    unsigned int type, bool increment);
 55extern int mtrr_add_page(unsigned long base, unsigned long size,
 56			 unsigned int type, bool increment);
 57extern int mtrr_del(int reg, unsigned long base, unsigned long size);
 58extern int mtrr_del_page(int reg, unsigned long base, unsigned long size);
 59extern int mtrr_trim_uncached_memory(unsigned long end_pfn);
 60extern int amd_special_default_mtrr(void);
 61void mtrr_disable(void);
 62void mtrr_enable(void);
 63void mtrr_generic_set_state(void);
 64#  else
 65static inline void guest_force_mtrr_state(struct mtrr_var_range *var,
 66					  unsigned int num_var,
 67					  mtrr_type def_type)
 68{
 69}
 70
 71static inline u8 mtrr_type_lookup(u64 addr, u64 end, u8 *uniform)
 72{
 73	/*
 74	 * Return the default MTRR type, without any known other types in
 75	 * that range.
 76	 */
 77	*uniform = 1;
 78
 79	return MTRR_TYPE_UNCACHABLE;
 80}
 81#define mtrr_save_fixed_ranges(arg) do {} while (0)
 82#define mtrr_save_state() do {} while (0)
 83static inline int mtrr_add(unsigned long base, unsigned long size,
 84			   unsigned int type, bool increment)
 85{
 86    return -ENODEV;
 87}
 88static inline int mtrr_add_page(unsigned long base, unsigned long size,
 89				unsigned int type, bool increment)
 90{
 91    return -ENODEV;
 92}
 93static inline int mtrr_del(int reg, unsigned long base, unsigned long size)
 94{
 95    return -ENODEV;
 96}
 97static inline int mtrr_del_page(int reg, unsigned long base, unsigned long size)
 98{
 99    return -ENODEV;
100}
101static inline int mtrr_trim_uncached_memory(unsigned long end_pfn)
102{
103	return 0;
104}
105#define mtrr_bp_init() do {} while (0)
106#define mtrr_disable() do {} while (0)
107#define mtrr_enable() do {} while (0)
108#define mtrr_generic_set_state() do {} while (0)
109#  endif
110
111#ifdef CONFIG_COMPAT
112#include <linux/compat.h>
113
114struct mtrr_sentry32 {
115    compat_ulong_t base;    /*  Base address     */
116    compat_uint_t size;    /*  Size of region   */
117    compat_uint_t type;     /*  Type of region   */
118};
119
120struct mtrr_gentry32 {
121    compat_ulong_t regnum;   /*  Register number  */
122    compat_uint_t base;    /*  Base address     */
123    compat_uint_t size;    /*  Size of region   */
124    compat_uint_t type;     /*  Type of region   */
125};
126
127#define MTRR_IOCTL_BASE 'M'
128
129#define MTRRIOC32_ADD_ENTRY      _IOW(MTRR_IOCTL_BASE,  0, struct mtrr_sentry32)
130#define MTRRIOC32_SET_ENTRY      _IOW(MTRR_IOCTL_BASE,  1, struct mtrr_sentry32)
131#define MTRRIOC32_DEL_ENTRY      _IOW(MTRR_IOCTL_BASE,  2, struct mtrr_sentry32)
132#define MTRRIOC32_GET_ENTRY      _IOWR(MTRR_IOCTL_BASE, 3, struct mtrr_gentry32)
133#define MTRRIOC32_KILL_ENTRY     _IOW(MTRR_IOCTL_BASE,  4, struct mtrr_sentry32)
134#define MTRRIOC32_ADD_PAGE_ENTRY _IOW(MTRR_IOCTL_BASE,  5, struct mtrr_sentry32)
135#define MTRRIOC32_SET_PAGE_ENTRY _IOW(MTRR_IOCTL_BASE,  6, struct mtrr_sentry32)
136#define MTRRIOC32_DEL_PAGE_ENTRY _IOW(MTRR_IOCTL_BASE,  7, struct mtrr_sentry32)
137#define MTRRIOC32_GET_PAGE_ENTRY _IOWR(MTRR_IOCTL_BASE, 8, struct mtrr_gentry32)
138#define MTRRIOC32_KILL_PAGE_ENTRY		\
139				 _IOW(MTRR_IOCTL_BASE,  9, struct mtrr_sentry32)
140#endif /* CONFIG_COMPAT */
141
142/* Bit fields for enabled in struct mtrr_state_type */
143#define MTRR_STATE_SHIFT		10
144#define MTRR_STATE_MTRR_FIXED_ENABLED	(MTRR_DEF_TYPE_FE >> MTRR_STATE_SHIFT)
145#define MTRR_STATE_MTRR_ENABLED		(MTRR_DEF_TYPE_E >> MTRR_STATE_SHIFT)
146
147#endif /* _ASM_X86_MTRR_H */