1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2012,2013 - ARM Ltd
4 * Author: Marc Zyngier <marc.zyngier@arm.com>
5 *
6 * Derived from arch/arm/kvm/coproc.h
7 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
8 * Authors: Christoffer Dall <c.dall@virtualopensystems.com>
9 */
10
11#ifndef __ARM64_KVM_SYS_REGS_LOCAL_H__
12#define __ARM64_KVM_SYS_REGS_LOCAL_H__
13
14struct sys_reg_params {
15	u8	Op0;
16	u8	Op1;
17	u8	CRn;
18	u8	CRm;
19	u8	Op2;
20	u64	regval;
21	bool	is_write;
22	bool	is_aarch32;
23	bool	is_32bit;	/* Only valid if is_aarch32 is true */
24};
25
26struct sys_reg_desc {
27	/* Sysreg string for debug */
28	const char *name;
29
30	/* MRS/MSR instruction which accesses it. */
31	u8	Op0;
32	u8	Op1;
33	u8	CRn;
34	u8	CRm;
35	u8	Op2;
36
37	/* Trapped access from guest, if non-NULL. */
38	bool (*access)(struct kvm_vcpu *,
39		       struct sys_reg_params *,
40		       const struct sys_reg_desc *);
41
42	/* Initialization for vcpu. */
43	void (*reset)(struct kvm_vcpu *, const struct sys_reg_desc *);
44
45	/* Index into sys_reg[], or 0 if we don't need to save it. */
46	int reg;
47
48	/* Value (usually reset value) */
49	u64 val;
50
51	/* Custom get/set_user functions, fallback to generic if NULL */
52	int (*get_user)(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
53			const struct kvm_one_reg *reg, void __user *uaddr);
54	int (*set_user)(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
55			const struct kvm_one_reg *reg, void __user *uaddr);
56
57	/* Return mask of REG_* runtime visibility overrides */
58	unsigned int (*visibility)(const struct kvm_vcpu *vcpu,
59				   const struct sys_reg_desc *rd);
60};
61
62#define REG_HIDDEN		(1 << 0) /* hidden from userspace and guest */
63#define REG_RAZ			(1 << 1) /* RAZ from userspace and guest */
64
65static __printf(2, 3)
66inline void print_sys_reg_msg(const struct sys_reg_params *p,
67				       char *fmt, ...)
68{
69	va_list va;
70
71	va_start(va, fmt);
72	/* Look, we even formatted it for you to paste into the table! */
73	kvm_pr_unimpl("%pV { Op0(%2u), Op1(%2u), CRn(%2u), CRm(%2u), Op2(%2u), func_%s },\n",
74		      &(struct va_format){ fmt, &va },
75		      p->Op0, p->Op1, p->CRn, p->CRm, p->Op2, p->is_write ? "write" : "read");
76	va_end(va);
77}
78
79static inline void print_sys_reg_instr(const struct sys_reg_params *p)
80{
81	/* GCC warns on an empty format string */
82	print_sys_reg_msg(p, "%s", "");
83}
84
85static inline bool ignore_write(struct kvm_vcpu *vcpu,
86				const struct sys_reg_params *p)
87{
88	return true;
89}
90
91static inline bool read_zero(struct kvm_vcpu *vcpu,
92			     struct sys_reg_params *p)
93{
94	p->regval = 0;
95	return true;
96}
97
98/* Reset functions */
99static inline void reset_unknown(struct kvm_vcpu *vcpu,
100				 const struct sys_reg_desc *r)
101{
102	BUG_ON(!r->reg);
103	BUG_ON(r->reg >= NR_SYS_REGS);
104	__vcpu_sys_reg(vcpu, r->reg) = 0x1de7ec7edbadc0deULL;
105}
106
107static inline void reset_val(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
108{
109	BUG_ON(!r->reg);
110	BUG_ON(r->reg >= NR_SYS_REGS);
111	__vcpu_sys_reg(vcpu, r->reg) = r->val;
112}
113
114static inline bool sysreg_hidden(const struct kvm_vcpu *vcpu,
115				 const struct sys_reg_desc *r)
116{
117	if (likely(!r->visibility))
118		return false;
119
120	return r->visibility(vcpu, r) & REG_HIDDEN;
121}
122
123static inline bool sysreg_visible_as_raz(const struct kvm_vcpu *vcpu,
124					 const struct sys_reg_desc *r)
125{
126	if (likely(!r->visibility))
127		return false;
128
129	return r->visibility(vcpu, r) & REG_RAZ;
130}
131
132static inline int cmp_sys_reg(const struct sys_reg_desc *i1,
133			      const struct sys_reg_desc *i2)
134{
135	BUG_ON(i1 == i2);
136	if (!i1)
137		return 1;
138	else if (!i2)
139		return -1;
140	if (i1->Op0 != i2->Op0)
141		return i1->Op0 - i2->Op0;
142	if (i1->Op1 != i2->Op1)
143		return i1->Op1 - i2->Op1;
144	if (i1->CRn != i2->CRn)
145		return i1->CRn - i2->CRn;
146	if (i1->CRm != i2->CRm)
147		return i1->CRm - i2->CRm;
148	return i1->Op2 - i2->Op2;
149}
150
151const struct sys_reg_desc *find_reg_by_id(u64 id,
152					  struct sys_reg_params *params,
153					  const struct sys_reg_desc table[],
154					  unsigned int num);
155
156#define Op0(_x) 	.Op0 = _x
157#define Op1(_x) 	.Op1 = _x
158#define CRn(_x)		.CRn = _x
159#define CRm(_x) 	.CRm = _x
160#define Op2(_x) 	.Op2 = _x
161
162#define SYS_DESC(reg)					\
163	.name = #reg,					\
164	Op0(sys_reg_Op0(reg)), Op1(sys_reg_Op1(reg)),	\
165	CRn(sys_reg_CRn(reg)), CRm(sys_reg_CRm(reg)),	\
166	Op2(sys_reg_Op2(reg))
167
168#endif /* __ARM64_KVM_SYS_REGS_LOCAL_H__ */
169