1 /*
2  * Copyright (C) 2015 - ARM Ltd
3  * Author: Marc Zyngier <marc.zyngier@arm.com>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #ifndef __ARM64_KVM_HYP_H__
19 #define __ARM64_KVM_HYP_H__
20 
21 #include <linux/compiler.h>
22 #include <linux/kvm_host.h>
23 #include <asm/sysreg.h>
24 
25 #define __hyp_text __section(.hyp.text) notrace
26 
27 #define read_sysreg_elx(r,nvh,vh)					\
28 	({								\
29 		u64 reg;						\
30 		asm volatile(ALTERNATIVE("mrs %0, " __stringify(r##nvh),\
31 					 "mrs_s %0, " __stringify(r##vh),\
32 					 ARM64_HAS_VIRT_HOST_EXTN)	\
33 			     : "=r" (reg));				\
34 		reg;							\
35 	})
36 
37 #define write_sysreg_elx(v,r,nvh,vh)					\
38 	do {								\
39 		u64 __val = (u64)(v);					\
40 		asm volatile(ALTERNATIVE("msr " __stringify(r##nvh) ", %x0",\
41 					 "msr_s " __stringify(r##vh) ", %x0",\
42 					 ARM64_HAS_VIRT_HOST_EXTN)	\
43 					 : : "rZ" (__val));		\
44 	} while (0)
45 
46 /*
47  * Unified accessors for registers that have a different encoding
48  * between VHE and non-VHE. They must be specified without their "ELx"
49  * encoding.
50  */
51 #define read_sysreg_el2(r)						\
52 	({								\
53 		u64 reg;						\
54 		asm volatile(ALTERNATIVE("mrs %0, " __stringify(r##_EL2),\
55 					 "mrs %0, " __stringify(r##_EL1),\
56 					 ARM64_HAS_VIRT_HOST_EXTN)	\
57 			     : "=r" (reg));				\
58 		reg;							\
59 	})
60 
61 #define write_sysreg_el2(v,r)						\
62 	do {								\
63 		u64 __val = (u64)(v);					\
64 		asm volatile(ALTERNATIVE("msr " __stringify(r##_EL2) ", %x0",\
65 					 "msr " __stringify(r##_EL1) ", %x0",\
66 					 ARM64_HAS_VIRT_HOST_EXTN)	\
67 					 : : "rZ" (__val));		\
68 	} while (0)
69 
70 #define read_sysreg_el0(r)	read_sysreg_elx(r, _EL0, _EL02)
71 #define write_sysreg_el0(v,r)	write_sysreg_elx(v, r, _EL0, _EL02)
72 #define read_sysreg_el1(r)	read_sysreg_elx(r, _EL1, _EL12)
73 #define write_sysreg_el1(v,r)	write_sysreg_elx(v, r, _EL1, _EL12)
74 
75 /* The VHE specific system registers and their encoding */
76 #define sctlr_EL12              sys_reg(3, 5, 1, 0, 0)
77 #define cpacr_EL12              sys_reg(3, 5, 1, 0, 2)
78 #define ttbr0_EL12              sys_reg(3, 5, 2, 0, 0)
79 #define ttbr1_EL12              sys_reg(3, 5, 2, 0, 1)
80 #define tcr_EL12                sys_reg(3, 5, 2, 0, 2)
81 #define afsr0_EL12              sys_reg(3, 5, 5, 1, 0)
82 #define afsr1_EL12              sys_reg(3, 5, 5, 1, 1)
83 #define esr_EL12                sys_reg(3, 5, 5, 2, 0)
84 #define far_EL12                sys_reg(3, 5, 6, 0, 0)
85 #define mair_EL12               sys_reg(3, 5, 10, 2, 0)
86 #define amair_EL12              sys_reg(3, 5, 10, 3, 0)
87 #define vbar_EL12               sys_reg(3, 5, 12, 0, 0)
88 #define contextidr_EL12         sys_reg(3, 5, 13, 0, 1)
89 #define cntkctl_EL12            sys_reg(3, 5, 14, 1, 0)
90 #define cntp_tval_EL02          sys_reg(3, 5, 14, 2, 0)
91 #define cntp_ctl_EL02           sys_reg(3, 5, 14, 2, 1)
92 #define cntp_cval_EL02          sys_reg(3, 5, 14, 2, 2)
93 #define cntv_tval_EL02          sys_reg(3, 5, 14, 3, 0)
94 #define cntv_ctl_EL02           sys_reg(3, 5, 14, 3, 1)
95 #define cntv_cval_EL02          sys_reg(3, 5, 14, 3, 2)
96 #define spsr_EL12               sys_reg(3, 5, 4, 0, 0)
97 #define elr_EL12                sys_reg(3, 5, 4, 0, 1)
98 
99 /**
100  * hyp_alternate_select - Generates patchable code sequences that are
101  * used to switch between two implementations of a function, depending
102  * on the availability of a feature.
103  *
104  * @fname: a symbol name that will be defined as a function returning a
105  * function pointer whose type will match @orig and @alt
106  * @orig: A pointer to the default function, as returned by @fname when
107  * @cond doesn't hold
108  * @alt: A pointer to the alternate function, as returned by @fname
109  * when @cond holds
110  * @cond: a CPU feature (as described in asm/cpufeature.h)
111  */
112 #define hyp_alternate_select(fname, orig, alt, cond)			\
113 typeof(orig) * __hyp_text fname(void)					\
114 {									\
115 	typeof(alt) *val = orig;					\
116 	asm volatile(ALTERNATIVE("nop		\n",			\
117 				 "mov	%0, %1	\n",			\
118 				 cond)					\
119 		     : "+r" (val) : "r" (alt));				\
120 	return val;							\
121 }
122 
123 int __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu);
124 
125 void __vgic_v3_save_state(struct kvm_vcpu *vcpu);
126 void __vgic_v3_restore_state(struct kvm_vcpu *vcpu);
127 void __vgic_v3_activate_traps(struct kvm_vcpu *vcpu);
128 void __vgic_v3_deactivate_traps(struct kvm_vcpu *vcpu);
129 void __vgic_v3_save_aprs(struct kvm_vcpu *vcpu);
130 void __vgic_v3_restore_aprs(struct kvm_vcpu *vcpu);
131 int __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu);
132 
133 void __timer_enable_traps(struct kvm_vcpu *vcpu);
134 void __timer_disable_traps(struct kvm_vcpu *vcpu);
135 
136 void __sysreg_save_state_nvhe(struct kvm_cpu_context *ctxt);
137 void __sysreg_restore_state_nvhe(struct kvm_cpu_context *ctxt);
138 void sysreg_save_host_state_vhe(struct kvm_cpu_context *ctxt);
139 void sysreg_restore_host_state_vhe(struct kvm_cpu_context *ctxt);
140 void sysreg_save_guest_state_vhe(struct kvm_cpu_context *ctxt);
141 void sysreg_restore_guest_state_vhe(struct kvm_cpu_context *ctxt);
142 void __sysreg32_save_state(struct kvm_vcpu *vcpu);
143 void __sysreg32_restore_state(struct kvm_vcpu *vcpu);
144 
145 void __debug_switch_to_guest(struct kvm_vcpu *vcpu);
146 void __debug_switch_to_host(struct kvm_vcpu *vcpu);
147 
148 void __fpsimd_save_state(struct user_fpsimd_state *fp_regs);
149 void __fpsimd_restore_state(struct user_fpsimd_state *fp_regs);
150 bool __fpsimd_enabled(void);
151 
152 void activate_traps_vhe_load(struct kvm_vcpu *vcpu);
153 void deactivate_traps_vhe_put(void);
154 
155 u64 __guest_enter(struct kvm_vcpu *vcpu, struct kvm_cpu_context *host_ctxt);
156 void __noreturn __hyp_do_panic(unsigned long, ...);
157 
158 #endif /* __ARM64_KVM_HYP_H__ */
159 
160