xref: /linux/arch/arm64/include/asm/kvm_hyp.h (revision 44f57d78)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2015 - ARM Ltd
4  * Author: Marc Zyngier <marc.zyngier@arm.com>
5  */
6 
7 #ifndef __ARM64_KVM_HYP_H__
8 #define __ARM64_KVM_HYP_H__
9 
10 #include <linux/compiler.h>
11 #include <linux/kvm_host.h>
12 #include <asm/alternative.h>
13 #include <asm/kvm_mmu.h>
14 #include <asm/sysreg.h>
15 
16 #define __hyp_text __section(.hyp.text) notrace
17 
18 #define read_sysreg_elx(r,nvh,vh)					\
19 	({								\
20 		u64 reg;						\
21 		asm volatile(ALTERNATIVE("mrs %0, " __stringify(r##nvh),\
22 					 __mrs_s("%0", r##vh),		\
23 					 ARM64_HAS_VIRT_HOST_EXTN)	\
24 			     : "=r" (reg));				\
25 		reg;							\
26 	})
27 
28 #define write_sysreg_elx(v,r,nvh,vh)					\
29 	do {								\
30 		u64 __val = (u64)(v);					\
31 		asm volatile(ALTERNATIVE("msr " __stringify(r##nvh) ", %x0",\
32 					 __msr_s(r##vh, "%x0"),		\
33 					 ARM64_HAS_VIRT_HOST_EXTN)	\
34 					 : : "rZ" (__val));		\
35 	} while (0)
36 
37 /*
38  * Unified accessors for registers that have a different encoding
39  * between VHE and non-VHE. They must be specified without their "ELx"
40  * encoding.
41  */
42 #define read_sysreg_el2(r)						\
43 	({								\
44 		u64 reg;						\
45 		asm volatile(ALTERNATIVE("mrs %0, " __stringify(r##_EL2),\
46 					 "mrs %0, " __stringify(r##_EL1),\
47 					 ARM64_HAS_VIRT_HOST_EXTN)	\
48 			     : "=r" (reg));				\
49 		reg;							\
50 	})
51 
52 #define write_sysreg_el2(v,r)						\
53 	do {								\
54 		u64 __val = (u64)(v);					\
55 		asm volatile(ALTERNATIVE("msr " __stringify(r##_EL2) ", %x0",\
56 					 "msr " __stringify(r##_EL1) ", %x0",\
57 					 ARM64_HAS_VIRT_HOST_EXTN)	\
58 					 : : "rZ" (__val));		\
59 	} while (0)
60 
61 #define read_sysreg_el0(r)	read_sysreg_elx(r, _EL0, _EL02)
62 #define write_sysreg_el0(v,r)	write_sysreg_elx(v, r, _EL0, _EL02)
63 #define read_sysreg_el1(r)	read_sysreg_elx(r, _EL1, _EL12)
64 #define write_sysreg_el1(v,r)	write_sysreg_elx(v, r, _EL1, _EL12)
65 
66 /* The VHE specific system registers and their encoding */
67 #define sctlr_EL12              sys_reg(3, 5, 1, 0, 0)
68 #define cpacr_EL12              sys_reg(3, 5, 1, 0, 2)
69 #define ttbr0_EL12              sys_reg(3, 5, 2, 0, 0)
70 #define ttbr1_EL12              sys_reg(3, 5, 2, 0, 1)
71 #define tcr_EL12                sys_reg(3, 5, 2, 0, 2)
72 #define afsr0_EL12              sys_reg(3, 5, 5, 1, 0)
73 #define afsr1_EL12              sys_reg(3, 5, 5, 1, 1)
74 #define esr_EL12                sys_reg(3, 5, 5, 2, 0)
75 #define far_EL12                sys_reg(3, 5, 6, 0, 0)
76 #define mair_EL12               sys_reg(3, 5, 10, 2, 0)
77 #define amair_EL12              sys_reg(3, 5, 10, 3, 0)
78 #define vbar_EL12               sys_reg(3, 5, 12, 0, 0)
79 #define contextidr_EL12         sys_reg(3, 5, 13, 0, 1)
80 #define cntkctl_EL12            sys_reg(3, 5, 14, 1, 0)
81 #define cntp_tval_EL02          sys_reg(3, 5, 14, 2, 0)
82 #define cntp_ctl_EL02           sys_reg(3, 5, 14, 2, 1)
83 #define cntp_cval_EL02          sys_reg(3, 5, 14, 2, 2)
84 #define cntv_tval_EL02          sys_reg(3, 5, 14, 3, 0)
85 #define cntv_ctl_EL02           sys_reg(3, 5, 14, 3, 1)
86 #define cntv_cval_EL02          sys_reg(3, 5, 14, 3, 2)
87 #define spsr_EL12               sys_reg(3, 5, 4, 0, 0)
88 #define elr_EL12                sys_reg(3, 5, 4, 0, 1)
89 
90 /**
91  * hyp_alternate_select - Generates patchable code sequences that are
92  * used to switch between two implementations of a function, depending
93  * on the availability of a feature.
94  *
95  * @fname: a symbol name that will be defined as a function returning a
96  * function pointer whose type will match @orig and @alt
97  * @orig: A pointer to the default function, as returned by @fname when
98  * @cond doesn't hold
99  * @alt: A pointer to the alternate function, as returned by @fname
100  * when @cond holds
101  * @cond: a CPU feature (as described in asm/cpufeature.h)
102  */
103 #define hyp_alternate_select(fname, orig, alt, cond)			\
104 typeof(orig) * __hyp_text fname(void)					\
105 {									\
106 	typeof(alt) *val = orig;					\
107 	asm volatile(ALTERNATIVE("nop		\n",			\
108 				 "mov	%0, %1	\n",			\
109 				 cond)					\
110 		     : "+r" (val) : "r" (alt));				\
111 	return val;							\
112 }
113 
114 int __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu);
115 
116 void __vgic_v3_save_state(struct kvm_vcpu *vcpu);
117 void __vgic_v3_restore_state(struct kvm_vcpu *vcpu);
118 void __vgic_v3_activate_traps(struct kvm_vcpu *vcpu);
119 void __vgic_v3_deactivate_traps(struct kvm_vcpu *vcpu);
120 void __vgic_v3_save_aprs(struct kvm_vcpu *vcpu);
121 void __vgic_v3_restore_aprs(struct kvm_vcpu *vcpu);
122 int __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu);
123 
124 void __timer_enable_traps(struct kvm_vcpu *vcpu);
125 void __timer_disable_traps(struct kvm_vcpu *vcpu);
126 
127 void __sysreg_save_state_nvhe(struct kvm_cpu_context *ctxt);
128 void __sysreg_restore_state_nvhe(struct kvm_cpu_context *ctxt);
129 void sysreg_save_host_state_vhe(struct kvm_cpu_context *ctxt);
130 void sysreg_restore_host_state_vhe(struct kvm_cpu_context *ctxt);
131 void sysreg_save_guest_state_vhe(struct kvm_cpu_context *ctxt);
132 void sysreg_restore_guest_state_vhe(struct kvm_cpu_context *ctxt);
133 void __sysreg32_save_state(struct kvm_vcpu *vcpu);
134 void __sysreg32_restore_state(struct kvm_vcpu *vcpu);
135 
136 void __debug_switch_to_guest(struct kvm_vcpu *vcpu);
137 void __debug_switch_to_host(struct kvm_vcpu *vcpu);
138 
139 void __fpsimd_save_state(struct user_fpsimd_state *fp_regs);
140 void __fpsimd_restore_state(struct user_fpsimd_state *fp_regs);
141 
142 void activate_traps_vhe_load(struct kvm_vcpu *vcpu);
143 void deactivate_traps_vhe_put(void);
144 
145 u64 __guest_enter(struct kvm_vcpu *vcpu, struct kvm_cpu_context *host_ctxt);
146 void __noreturn __hyp_do_panic(unsigned long, ...);
147 
148 /*
149  * Must be called from hyp code running at EL2 with an updated VTTBR
150  * and interrupts disabled.
151  */
152 static __always_inline void __hyp_text __load_guest_stage2(struct kvm *kvm)
153 {
154 	write_sysreg(kvm->arch.vtcr, vtcr_el2);
155 	write_sysreg(kvm_get_vttbr(kvm), vttbr_el2);
156 
157 	/*
158 	 * ARM erratum 1165522 requires the actual execution of the above
159 	 * before we can switch to the EL1/EL0 translation regime used by
160 	 * the guest.
161 	 */
162 	asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_1165522));
163 }
164 
165 #endif /* __ARM64_KVM_HYP_H__ */
166 
167