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
14#include <linux/bsearch.h>
15
16#define reg_to_encoding(x)						\
17	sys_reg((u32)(x)->Op0, (u32)(x)->Op1,				\
18		(u32)(x)->CRn, (u32)(x)->CRm, (u32)(x)->Op2)
19
20struct sys_reg_params {
21	u8	Op0;
22	u8	Op1;
23	u8	CRn;
24	u8	CRm;
25	u8	Op2;
26	u64	regval;
27	bool	is_write;
28};
29
30#define encoding_to_params(reg)						\
31	((struct sys_reg_params){ .Op0 = sys_reg_Op0(reg),		\
32				  .Op1 = sys_reg_Op1(reg),		\
33				  .CRn = sys_reg_CRn(reg),		\
34				  .CRm = sys_reg_CRm(reg),		\
35				  .Op2 = sys_reg_Op2(reg) })
36
37#define esr_sys64_to_params(esr)                                               \
38	((struct sys_reg_params){ .Op0 = ((esr) >> 20) & 3,                    \
39				  .Op1 = ((esr) >> 14) & 0x7,                  \
40				  .CRn = ((esr) >> 10) & 0xf,                  \
41				  .CRm = ((esr) >> 1) & 0xf,                   \
42				  .Op2 = ((esr) >> 17) & 0x7,                  \
43				  .is_write = !((esr) & 1) })
44
45#define esr_cp1x_32_to_params(esr)						\
46	((struct sys_reg_params){ .Op1 = ((esr) >> 14) & 0x7,			\
47				  .CRn = ((esr) >> 10) & 0xf,			\
48				  .CRm = ((esr) >> 1) & 0xf,			\
49				  .Op2 = ((esr) >> 17) & 0x7,			\
50				  .is_write = !((esr) & 1) })
51
52struct sys_reg_desc {
53	/* Sysreg string for debug */
54	const char *name;
55
56	enum {
57		AA32_DIRECT,
58		AA32_LO,
59		AA32_HI,
60	} aarch32_map;
61
62	/* MRS/MSR instruction which accesses it. */
63	u8	Op0;
64	u8	Op1;
65	u8	CRn;
66	u8	CRm;
67	u8	Op2;
68
69	/* Trapped access from guest, if non-NULL. */
70	bool (*access)(struct kvm_vcpu *,
71		       struct sys_reg_params *,
72		       const struct sys_reg_desc *);
73
74	/*
75	 * Initialization for vcpu. Return initialized value, or KVM
76	 * sanitized value for ID registers.
77	 */
78	u64 (*reset)(struct kvm_vcpu *, const struct sys_reg_desc *);
79
80	/* Index into sys_reg[], or 0 if we don't need to save it. */
81	int reg;
82
83	/* Value (usually reset value), or write mask for idregs */
84	u64 val;
85
86	/* Custom get/set_user functions, fallback to generic if NULL */
87	int (*get_user)(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
88			u64 *val);
89	int (*set_user)(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
90			u64 val);
91
92	/* Return mask of REG_* runtime visibility overrides */
93	unsigned int (*visibility)(const struct kvm_vcpu *vcpu,
94				   const struct sys_reg_desc *rd);
95};
96
97#define REG_HIDDEN		(1 << 0) /* hidden from userspace and guest */
98#define REG_HIDDEN_USER		(1 << 1) /* hidden from userspace only */
99#define REG_RAZ			(1 << 2) /* RAZ from userspace and guest */
100#define REG_USER_WI		(1 << 3) /* WI from userspace only */
101
102static __printf(2, 3)
103inline void print_sys_reg_msg(const struct sys_reg_params *p,
104				       char *fmt, ...)
105{
106	va_list va;
107
108	va_start(va, fmt);
109	/* Look, we even formatted it for you to paste into the table! */
110	kvm_pr_unimpl("%pV { Op0(%2u), Op1(%2u), CRn(%2u), CRm(%2u), Op2(%2u), func_%s },\n",
111		      &(struct va_format){ fmt, &va },
112		      p->Op0, p->Op1, p->CRn, p->CRm, p->Op2, p->is_write ? "write" : "read");
113	va_end(va);
114}
115
116static inline void print_sys_reg_instr(const struct sys_reg_params *p)
117{
118	/* GCC warns on an empty format string */
119	print_sys_reg_msg(p, "%s", "");
120}
121
122static inline bool ignore_write(struct kvm_vcpu *vcpu,
123				const struct sys_reg_params *p)
124{
125	return true;
126}
127
128static inline bool read_zero(struct kvm_vcpu *vcpu,
129			     struct sys_reg_params *p)
130{
131	p->regval = 0;
132	return true;
133}
134
135/* Reset functions */
136static inline u64 reset_unknown(struct kvm_vcpu *vcpu,
137				 const struct sys_reg_desc *r)
138{
139	BUG_ON(!r->reg);
140	BUG_ON(r->reg >= NR_SYS_REGS);
141	__vcpu_sys_reg(vcpu, r->reg) = 0x1de7ec7edbadc0deULL;
142	return __vcpu_sys_reg(vcpu, r->reg);
143}
144
145static inline u64 reset_val(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
146{
147	BUG_ON(!r->reg);
148	BUG_ON(r->reg >= NR_SYS_REGS);
149	__vcpu_sys_reg(vcpu, r->reg) = r->val;
150	return __vcpu_sys_reg(vcpu, r->reg);
151}
152
153static inline unsigned int sysreg_visibility(const struct kvm_vcpu *vcpu,
154					     const struct sys_reg_desc *r)
155{
156	if (likely(!r->visibility))
157		return 0;
158
159	return r->visibility(vcpu, r);
160}
161
162static inline bool sysreg_hidden(const struct kvm_vcpu *vcpu,
163				 const struct sys_reg_desc *r)
164{
165	return sysreg_visibility(vcpu, r) & REG_HIDDEN;
166}
167
168static inline bool sysreg_hidden_user(const struct kvm_vcpu *vcpu,
169				      const struct sys_reg_desc *r)
170{
171	if (likely(!r->visibility))
172		return false;
173
174	return r->visibility(vcpu, r) & (REG_HIDDEN | REG_HIDDEN_USER);
175}
176
177static inline bool sysreg_visible_as_raz(const struct kvm_vcpu *vcpu,
178					 const struct sys_reg_desc *r)
179{
180	return sysreg_visibility(vcpu, r) & REG_RAZ;
181}
182
183static inline bool sysreg_user_write_ignore(const struct kvm_vcpu *vcpu,
184					    const struct sys_reg_desc *r)
185{
186	return sysreg_visibility(vcpu, r) & REG_USER_WI;
187}
188
189static inline int cmp_sys_reg(const struct sys_reg_desc *i1,
190			      const struct sys_reg_desc *i2)
191{
192	BUG_ON(i1 == i2);
193	if (!i1)
194		return 1;
195	else if (!i2)
196		return -1;
197	if (i1->Op0 != i2->Op0)
198		return i1->Op0 - i2->Op0;
199	if (i1->Op1 != i2->Op1)
200		return i1->Op1 - i2->Op1;
201	if (i1->CRn != i2->CRn)
202		return i1->CRn - i2->CRn;
203	if (i1->CRm != i2->CRm)
204		return i1->CRm - i2->CRm;
205	return i1->Op2 - i2->Op2;
206}
207
208static inline int match_sys_reg(const void *key, const void *elt)
209{
210	const unsigned long pval = (unsigned long)key;
211	const struct sys_reg_desc *r = elt;
212
213	return pval - reg_to_encoding(r);
214}
215
216static inline const struct sys_reg_desc *
217find_reg(const struct sys_reg_params *params, const struct sys_reg_desc table[],
218	 unsigned int num)
219{
220	unsigned long pval = reg_to_encoding(params);
221
222	return __inline_bsearch((void *)pval, table, num, sizeof(table[0]), match_sys_reg);
223}
224
225const struct sys_reg_desc *get_reg_by_id(u64 id,
226					 const struct sys_reg_desc table[],
227					 unsigned int num);
228
229int kvm_arm_sys_reg_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *);
230int kvm_arm_sys_reg_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *);
231int kvm_sys_reg_get_user(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg,
232			 const struct sys_reg_desc table[], unsigned int num);
233int kvm_sys_reg_set_user(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg,
234			 const struct sys_reg_desc table[], unsigned int num);
235
236bool triage_sysreg_trap(struct kvm_vcpu *vcpu, int *sr_index);
237
238#define AA32(_x)	.aarch32_map = AA32_##_x
239#define Op0(_x) 	.Op0 = _x
240#define Op1(_x) 	.Op1 = _x
241#define CRn(_x)		.CRn = _x
242#define CRm(_x) 	.CRm = _x
243#define Op2(_x) 	.Op2 = _x
244
245#define SYS_DESC(reg)					\
246	.name = #reg,					\
247	Op0(sys_reg_Op0(reg)), Op1(sys_reg_Op1(reg)),	\
248	CRn(sys_reg_CRn(reg)), CRm(sys_reg_CRm(reg)),	\
249	Op2(sys_reg_Op2(reg))
250
251#endif /* __ARM64_KVM_SYS_REGS_LOCAL_H__ */
252