arch/arm64/include/asm/kvm_hyp.h

   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/alternative.h>
  24 #include <asm/kvm_mmu.h>
  25 #include <asm/sysreg.h>
  26
  27 #define __hyp_text __section(.hyp.text) notrace
  28
  29 #define read_sysreg_elx(r,nvh,vh)                                       \
  30         ({                                                              \
  31                 u64 reg;                                                \
  32                 asm volatile(ALTERNATIVE("mrs %0, " __stringify(r##nvh),\
  33                                          __mrs_s("%0", r##vh),          \
  34                                          ARM64_HAS_VIRT_HOST_EXTN)      \
  35                              : "=r" (reg));                             \
  36                 reg;                                                    \
  37         })
  38
  39 #define write_sysreg_elx(v,r,nvh,vh)                                    \
  40         do {                                                            \
  41                 u64 __val = (u64)(v);                                   \
  42                 asm volatile(ALTERNATIVE("msr " __stringify(r##nvh) ", %x0",\
  43                                          __msr_s(r##vh, "%x0"),         \
  44                                          ARM64_HAS_VIRT_HOST_EXTN)      \
  45                                          : : "rZ" (__val));             \
  46         } while (0)
  47
  48 /*
  49  * Unified accessors for registers that have a different encoding
  50  * between VHE and non-VHE. They must be specified without their "ELx"
  51  * encoding.
  52  */
  53 #define read_sysreg_el2(r)                                              \
  54         ({                                                              \
  55                 u64 reg;                                                \
  56                 asm volatile(ALTERNATIVE("mrs %0, " __stringify(r##_EL2),\
  57                                          "mrs %0, " __stringify(r##_EL1),\
  58                                          ARM64_HAS_VIRT_HOST_EXTN)      \
  59                              : "=r" (reg));                             \
  60                 reg;                                                    \
  61         })
  62
  63 #define write_sysreg_el2(v,r)                                           \
  64         do {                                                            \
  65                 u64 __val = (u64)(v);                                   \
  66                 asm volatile(ALTERNATIVE("msr " __stringify(r##_EL2) ", %x0",\
  67                                          "msr " __stringify(r##_EL1) ", %x0",\
  68                                          ARM64_HAS_VIRT_HOST_EXTN)      \
  69                                          : : "rZ" (__val));             \
  70         } while (0)
  71
  72 #define read_sysreg_el0(r)      read_sysreg_elx(r, _EL0, _EL02)
  73 #define write_sysreg_el0(v,r)   write_sysreg_elx(v, r, _EL0, _EL02)
  74 #define read_sysreg_el1(r)      read_sysreg_elx(r, _EL1, _EL12)
  75 #define write_sysreg_el1(v,r)   write_sysreg_elx(v, r, _EL1, _EL12)
  76
  77 /* The VHE specific system registers and their encoding */
  78 #define sctlr_EL12              sys_reg(3, 5, 1, 0, 0)
  79 #define cpacr_EL12              sys_reg(3, 5, 1, 0, 2)
  80 #define ttbr0_EL12              sys_reg(3, 5, 2, 0, 0)
  81 #define ttbr1_EL12              sys_reg(3, 5, 2, 0, 1)
  82 #define tcr_EL12                sys_reg(3, 5, 2, 0, 2)
  83 #define afsr0_EL12              sys_reg(3, 5, 5, 1, 0)
  84 #define afsr1_EL12              sys_reg(3, 5, 5, 1, 1)
  85 #define esr_EL12                sys_reg(3, 5, 5, 2, 0)
  86 #define far_EL12                sys_reg(3, 5, 6, 0, 0)
  87 #define mair_EL12               sys_reg(3, 5, 10, 2, 0)
  88 #define amair_EL12              sys_reg(3, 5, 10, 3, 0)
  89 #define vbar_EL12               sys_reg(3, 5, 12, 0, 0)
  90 #define contextidr_EL12         sys_reg(3, 5, 13, 0, 1)
  91 #define cntkctl_EL12            sys_reg(3, 5, 14, 1, 0)
  92 #define cntp_tval_EL02          sys_reg(3, 5, 14, 2, 0)
  93 #define cntp_ctl_EL02           sys_reg(3, 5, 14, 2, 1)
  94 #define cntp_cval_EL02          sys_reg(3, 5, 14, 2, 2)
  95 #define cntv_tval_EL02          sys_reg(3, 5, 14, 3, 0)
  96 #define cntv_ctl_EL02           sys_reg(3, 5, 14, 3, 1)
  97 #define cntv_cval_EL02          sys_reg(3, 5, 14, 3, 2)
  98 #define spsr_EL12               sys_reg(3, 5, 4, 0, 0)
  99 #define elr_EL12                sys_reg(3, 5, 4, 0, 1)
 100
 101 /**
 102  * hyp_alternate_select - Generates patchable code sequences that are
 103  * used to switch between two implementations of a function, depending
 104  * on the availability of a feature.
 105  *
 106  * @fname: a symbol name that will be defined as a function returning a
 107  * function pointer whose type will match @orig and @alt
 108  * @orig: A pointer to the default function, as returned by @fname when
 109  * @cond doesn't hold
 110  * @alt: A pointer to the alternate function, as returned by @fname
 111  * when @cond holds
 112  * @cond: a CPU feature (as described in asm/cpufeature.h)
 113  */
 114 #define hyp_alternate_select(fname, orig, alt, cond)                    \
 115 typeof(orig) * __hyp_text fname(void)                                   \
 116 {                                                                       \
 117         typeof(alt) *val = orig;                                        \
 118         asm volatile(ALTERNATIVE("nop           \n",                    \
 119                                  "mov   %0, %1  \n",                    \
 120                                  cond)                                  \
 121                      : "+r" (val) : "r" (alt));                         \
 122         return val;                                                     \
 123 }
 124
 125 int __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu);
 126
 127 void __vgic_v3_save_state(struct kvm_vcpu *vcpu);
 128 void __vgic_v3_restore_state(struct kvm_vcpu *vcpu);
 129 void __vgic_v3_activate_traps(struct kvm_vcpu *vcpu);
 130 void __vgic_v3_deactivate_traps(struct kvm_vcpu *vcpu);
 131 void __vgic_v3_save_aprs(struct kvm_vcpu *vcpu);
 132 void __vgic_v3_restore_aprs(struct kvm_vcpu *vcpu);
 133 int __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu);
 134
 135 void __timer_enable_traps(struct kvm_vcpu *vcpu);
 136 void __timer_disable_traps(struct kvm_vcpu *vcpu);
 137
 138 void __sysreg_save_state_nvhe(struct kvm_cpu_context *ctxt);
 139 void __sysreg_restore_state_nvhe(struct kvm_cpu_context *ctxt);
 140 void sysreg_save_host_state_vhe(struct kvm_cpu_context *ctxt);
 141 void sysreg_restore_host_state_vhe(struct kvm_cpu_context *ctxt);
 142 void sysreg_save_guest_state_vhe(struct kvm_cpu_context *ctxt);
 143 void sysreg_restore_guest_state_vhe(struct kvm_cpu_context *ctxt);
 144 void __sysreg32_save_state(struct kvm_vcpu *vcpu);
 145 void __sysreg32_restore_state(struct kvm_vcpu *vcpu);
 146
 147 void __debug_switch_to_guest(struct kvm_vcpu *vcpu);
 148 void __debug_switch_to_host(struct kvm_vcpu *vcpu);
 149
 150 void __fpsimd_save_state(struct user_fpsimd_state *fp_regs);
 151 void __fpsimd_restore_state(struct user_fpsimd_state *fp_regs);
 152
 153 void activate_traps_vhe_load(struct kvm_vcpu *vcpu);
 154 void deactivate_traps_vhe_put(void);
 155
 156 u64 __guest_enter(struct kvm_vcpu *vcpu, struct kvm_cpu_context *host_ctxt);
 157 void __noreturn __hyp_do_panic(unsigned long, ...);
 158
 159 /*
 160  * Must be called from hyp code running at EL2 with an updated VTTBR
 161  * and interrupts disabled.
 162  */
 163 static __always_inline void __hyp_text __load_guest_stage2(struct kvm *kvm)
 164 {
 165         write_sysreg(kvm->arch.vtcr, vtcr_el2);
 166         write_sysreg(kvm_get_vttbr(kvm), vttbr_el2);
 167
 168         /*
 169          * ARM erratum 1165522 requires the actual execution of the above
 170          * before we can switch to the EL1/EL0 translation regime used by
 171          * the guest.
 172          */
 173         asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_1165522));
 174 }
 175
 176 #endif /* __ARM64_KVM_HYP_H__ */
 177