xref: /openbmc/linux/arch/arm64/include/asm/kvm_asm.h (revision 800e26b8)
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 
7 #ifndef __ARM_KVM_ASM_H__
8 #define __ARM_KVM_ASM_H__
9 
10 #include <asm/virt.h>
11 
12 #define	VCPU_WORKAROUND_2_FLAG_SHIFT	0
13 #define	VCPU_WORKAROUND_2_FLAG		(_AC(1, UL) << VCPU_WORKAROUND_2_FLAG_SHIFT)
14 
15 #define ARM_EXIT_WITH_SERROR_BIT  31
16 #define ARM_EXCEPTION_CODE(x)	  ((x) & ~(1U << ARM_EXIT_WITH_SERROR_BIT))
17 #define ARM_EXCEPTION_IS_TRAP(x)  (ARM_EXCEPTION_CODE((x)) == ARM_EXCEPTION_TRAP)
18 #define ARM_SERROR_PENDING(x)	  !!((x) & (1U << ARM_EXIT_WITH_SERROR_BIT))
19 
20 #define ARM_EXCEPTION_IRQ	  0
21 #define ARM_EXCEPTION_EL1_SERROR  1
22 #define ARM_EXCEPTION_TRAP	  2
23 #define ARM_EXCEPTION_IL	  3
24 /* The hyp-stub will return this for any kvm_call_hyp() call */
25 #define ARM_EXCEPTION_HYP_GONE	  HVC_STUB_ERR
26 
27 #define kvm_arm_exception_type					\
28 	{ARM_EXCEPTION_IRQ,		"IRQ"		},	\
29 	{ARM_EXCEPTION_EL1_SERROR, 	"SERROR"	},	\
30 	{ARM_EXCEPTION_TRAP, 		"TRAP"		},	\
31 	{ARM_EXCEPTION_HYP_GONE,	"HYP_GONE"	}
32 
33 /*
34  * Size of the HYP vectors preamble. kvm_patch_vector_branch() generates code
35  * that jumps over this.
36  */
37 #define KVM_VECTOR_PREAMBLE	(2 * AARCH64_INSN_SIZE)
38 
39 #define __SMCCC_WORKAROUND_1_SMC_SZ 36
40 
41 #ifndef __ASSEMBLY__
42 
43 #include <linux/mm.h>
44 
45 /* Translate a kernel address of @sym into its equivalent linear mapping */
46 #define kvm_ksym_ref(sym)						\
47 	({								\
48 		void *val = &sym;					\
49 		if (!is_kernel_in_hyp_mode())				\
50 			val = lm_alias(&sym);				\
51 		val;							\
52 	 })
53 
54 struct kvm;
55 struct kvm_vcpu;
56 
57 extern char __kvm_hyp_init[];
58 extern char __kvm_hyp_init_end[];
59 
60 extern char __kvm_hyp_vector[];
61 
62 extern void __kvm_flush_vm_context(void);
63 extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa);
64 extern void __kvm_tlb_flush_vmid(struct kvm *kvm);
65 extern void __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu);
66 
67 extern void __kvm_timer_set_cntvoff(u64 cntvoff);
68 
69 extern int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu);
70 
71 extern int __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu);
72 
73 extern void __kvm_enable_ssbs(void);
74 
75 extern u64 __vgic_v3_get_ich_vtr_el2(void);
76 extern u64 __vgic_v3_read_vmcr(void);
77 extern void __vgic_v3_write_vmcr(u32 vmcr);
78 extern void __vgic_v3_init_lrs(void);
79 
80 extern u32 __kvm_get_mdcr_el2(void);
81 
82 extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ];
83 
84 /*
85  * Obtain the PC-relative address of a kernel symbol
86  * s: symbol
87  *
88  * The goal of this macro is to return a symbol's address based on a
89  * PC-relative computation, as opposed to a loading the VA from a
90  * constant pool or something similar. This works well for HYP, as an
91  * absolute VA is guaranteed to be wrong. Only use this if trying to
92  * obtain the address of a symbol (i.e. not something you obtained by
93  * following a pointer).
94  */
95 #define hyp_symbol_addr(s)						\
96 	({								\
97 		typeof(s) *addr;					\
98 		asm("adrp	%0, %1\n"				\
99 		    "add	%0, %0, :lo12:%1\n"			\
100 		    : "=r" (addr) : "S" (&s));				\
101 		addr;							\
102 	})
103 
104 /*
105  * Home-grown __this_cpu_{ptr,read} variants that always work at HYP,
106  * provided that sym is really a *symbol* and not a pointer obtained from
107  * a data structure. As for SHIFT_PERCPU_PTR(), the creative casting keeps
108  * sparse quiet.
109  */
110 #define __hyp_this_cpu_ptr(sym)						\
111 	({								\
112 		void *__ptr;						\
113 		__verify_pcpu_ptr(&sym);				\
114 		__ptr = hyp_symbol_addr(sym);				\
115 		__ptr += read_sysreg(tpidr_el2);			\
116 		(typeof(sym) __kernel __force *)__ptr;			\
117 	 })
118 
119 #define __hyp_this_cpu_read(sym)					\
120 	({								\
121 		*__hyp_this_cpu_ptr(sym);				\
122 	 })
123 
124 #else /* __ASSEMBLY__ */
125 
126 .macro hyp_adr_this_cpu reg, sym, tmp
127 	adr_l	\reg, \sym
128 	mrs	\tmp, tpidr_el2
129 	add	\reg, \reg, \tmp
130 .endm
131 
132 .macro hyp_ldr_this_cpu reg, sym, tmp
133 	adr_l	\reg, \sym
134 	mrs	\tmp, tpidr_el2
135 	ldr	\reg,  [\reg, \tmp]
136 .endm
137 
138 .macro get_host_ctxt reg, tmp
139 	hyp_adr_this_cpu \reg, kvm_host_data, \tmp
140 	add	\reg, \reg, #HOST_DATA_CONTEXT
141 .endm
142 
143 .macro get_vcpu_ptr vcpu, ctxt
144 	get_host_ctxt \ctxt, \vcpu
145 	ldr	\vcpu, [\ctxt, #HOST_CONTEXT_VCPU]
146 	kern_hyp_va	\vcpu
147 .endm
148 
149 #endif
150 
151 #endif /* __ARM_KVM_ASM_H__ */
152