arch/arm64/kvm/sys_regs.h

   1 /*
   2  * Copyright (C) 2012,2013 - ARM Ltd
   3  * Author: Marc Zyngier <marc.zyngier@arm.com>
   4  *
   5  * Derived from arch/arm/kvm/coproc.h
   6  * Copyright (C) 2012 - Virtual Open Systems and Columbia University
   7  * Authors: Christoffer Dall <c.dall@virtualopensystems.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License, version 2, as
  11  * published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22 #ifndef __ARM64_KVM_SYS_REGS_LOCAL_H__
  23 #define __ARM64_KVM_SYS_REGS_LOCAL_H__
  24
  25 struct sys_reg_params {
  26         u8      Op0;
  27         u8      Op1;
  28         u8      CRn;
  29         u8      CRm;
  30         u8      Op2;
  31         u8      Rt;
  32         bool    is_write;
  33         bool    is_aarch32;
  34         bool    is_32bit;       /* Only valid if is_aarch32 is true */
  35 };
  36
  37 struct sys_reg_desc {
  38         /* MRS/MSR instruction which accesses it. */
  39         u8      Op0;
  40         u8      Op1;
  41         u8      CRn;
  42         u8      CRm;
  43         u8      Op2;
  44
  45         /* Trapped access from guest, if non-NULL. */
  46         bool (*access)(struct kvm_vcpu *,
  47                        const struct sys_reg_params *,
  48                        const struct sys_reg_desc *);
  49
  50         /* Initialization for vcpu. */
  51         void (*reset)(struct kvm_vcpu *, const struct sys_reg_desc *);
  52
  53         /* Index into sys_reg[], or 0 if we don't need to save it. */
  54         int reg;
  55
  56         /* Value (usually reset value) */
  57         u64 val;
  58 };
  59
  60 static inline void print_sys_reg_instr(const struct sys_reg_params *p)
  61 {
  62         /* Look, we even formatted it for you to paste into the table! */
  63         kvm_pr_unimpl(" { Op0(%2u), Op1(%2u), CRn(%2u), CRm(%2u), Op2(%2u), func_%s },\n",
  64                       p->Op0, p->Op1, p->CRn, p->CRm, p->Op2, p->is_write ? "write" : "read");
  65 }
  66
  67 static inline bool ignore_write(struct kvm_vcpu *vcpu,
  68                                 const struct sys_reg_params *p)
  69 {
  70         return true;
  71 }
  72
  73 static inline bool read_zero(struct kvm_vcpu *vcpu,
  74                              const struct sys_reg_params *p)
  75 {
  76         *vcpu_reg(vcpu, p->Rt) = 0;
  77         return true;
  78 }
  79
  80 static inline bool write_to_read_only(struct kvm_vcpu *vcpu,
  81                                       const struct sys_reg_params *params)
  82 {
  83         kvm_debug("sys_reg write to read-only register at: %lx\n",
  84                   *vcpu_pc(vcpu));
  85         print_sys_reg_instr(params);
  86         return false;
  87 }
  88
  89 static inline bool read_from_write_only(struct kvm_vcpu *vcpu,
  90                                         const struct sys_reg_params *params)
  91 {
  92         kvm_debug("sys_reg read to write-only register at: %lx\n",
  93                   *vcpu_pc(vcpu));
  94         print_sys_reg_instr(params);
  95         return false;
  96 }
  97
  98 /* Reset functions */
  99 static inline void reset_unknown(struct kvm_vcpu *vcpu,
 100                                  const struct sys_reg_desc *r)
 101 {
 102         BUG_ON(!r->reg);
 103         BUG_ON(r->reg >= NR_SYS_REGS);
 104         vcpu_sys_reg(vcpu, r->reg) = 0x1de7ec7edbadc0deULL;
 105 }
 106
 107 static inline void reset_val(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r)
 108 {
 109         BUG_ON(!r->reg);
 110         BUG_ON(r->reg >= NR_SYS_REGS);
 111         vcpu_sys_reg(vcpu, r->reg) = r->val;
 112 }
 113
 114 static inline int cmp_sys_reg(const struct sys_reg_desc *i1,
 115                               const struct sys_reg_desc *i2)
 116 {
 117         BUG_ON(i1 == i2);
 118         if (!i1)
 119                 return 1;
 120         else if (!i2)
 121                 return -1;
 122         if (i1->Op0 != i2->Op0)
 123                 return i1->Op0 - i2->Op0;
 124         if (i1->Op1 != i2->Op1)
 125                 return i1->Op1 - i2->Op1;
 126         if (i1->CRn != i2->CRn)
 127                 return i1->CRn - i2->CRn;
 128         if (i1->CRm != i2->CRm)
 129                 return i1->CRm - i2->CRm;
 130         return i1->Op2 - i2->Op2;
 131 }
 132
 133
 134 #define Op0(_x)         .Op0 = _x
 135 #define Op1(_x)         .Op1 = _x
 136 #define CRn(_x)         .CRn = _x
 137 #define CRm(_x)         .CRm = _x
 138 #define Op2(_x)         .Op2 = _x
 139
 140 #endif /* __ARM64_KVM_SYS_REGS_LOCAL_H__ */