arch/arm64/kvm/hyp/debug-sr.c

   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 #include <linux/compiler.h>
  19 #include <linux/kvm_host.h>
  20
  21 #include <asm/kvm_asm.h>
  22 #include <asm/kvm_hyp.h>
  23
  24 #define read_debug(r,n)         read_sysreg(r##n##_el1)
  25 #define write_debug(v,r,n)      write_sysreg(v, r##n##_el1)
  26
  27 #define save_debug(ptr,reg,nr)                                          \
  28         switch (nr) {                                                   \
  29         case 15:        ptr[15] = read_debug(reg, 15);                  \
  30         case 14:        ptr[14] = read_debug(reg, 14);                  \
  31         case 13:        ptr[13] = read_debug(reg, 13);                  \
  32         case 12:        ptr[12] = read_debug(reg, 12);                  \
  33         case 11:        ptr[11] = read_debug(reg, 11);                  \
  34         case 10:        ptr[10] = read_debug(reg, 10);                  \
  35         case 9:         ptr[9] = read_debug(reg, 9);                    \
  36         case 8:         ptr[8] = read_debug(reg, 8);                    \
  37         case 7:         ptr[7] = read_debug(reg, 7);                    \
  38         case 6:         ptr[6] = read_debug(reg, 6);                    \
  39         case 5:         ptr[5] = read_debug(reg, 5);                    \
  40         case 4:         ptr[4] = read_debug(reg, 4);                    \
  41         case 3:         ptr[3] = read_debug(reg, 3);                    \
  42         case 2:         ptr[2] = read_debug(reg, 2);                    \
  43         case 1:         ptr[1] = read_debug(reg, 1);                    \
  44         default:        ptr[0] = read_debug(reg, 0);                    \
  45         }
  46
  47 #define restore_debug(ptr,reg,nr)                                       \
  48         switch (nr) {                                                   \
  49         case 15:        write_debug(ptr[15], reg, 15);                  \
  50         case 14:        write_debug(ptr[14], reg, 14);                  \
  51         case 13:        write_debug(ptr[13], reg, 13);                  \
  52         case 12:        write_debug(ptr[12], reg, 12);                  \
  53         case 11:        write_debug(ptr[11], reg, 11);                  \
  54         case 10:        write_debug(ptr[10], reg, 10);                  \
  55         case 9:         write_debug(ptr[9], reg, 9);                    \
  56         case 8:         write_debug(ptr[8], reg, 8);                    \
  57         case 7:         write_debug(ptr[7], reg, 7);                    \
  58         case 6:         write_debug(ptr[6], reg, 6);                    \
  59         case 5:         write_debug(ptr[5], reg, 5);                    \
  60         case 4:         write_debug(ptr[4], reg, 4);                    \
  61         case 3:         write_debug(ptr[3], reg, 3);                    \
  62         case 2:         write_debug(ptr[2], reg, 2);                    \
  63         case 1:         write_debug(ptr[1], reg, 1);                    \
  64         default:        write_debug(ptr[0], reg, 0);                    \
  65         }
  66
  67 void __hyp_text __debug_save_state(struct kvm_vcpu *vcpu,
  68                                    struct kvm_guest_debug_arch *dbg,
  69                                    struct kvm_cpu_context *ctxt)
  70 {
  71         u64 aa64dfr0;
  72         int brps, wrps;
  73
  74         if (!(vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY))
  75                 return;
  76
  77         aa64dfr0 = read_sysreg(id_aa64dfr0_el1);
  78         brps = (aa64dfr0 >> 12) & 0xf;
  79         wrps = (aa64dfr0 >> 20) & 0xf;
  80
  81         save_debug(dbg->dbg_bcr, dbgbcr, brps);
  82         save_debug(dbg->dbg_bvr, dbgbvr, brps);
  83         save_debug(dbg->dbg_wcr, dbgwcr, wrps);
  84         save_debug(dbg->dbg_wvr, dbgwvr, wrps);
  85
  86         ctxt->sys_regs[MDCCINT_EL1] = read_sysreg(mdccint_el1);
  87 }
  88
  89 void __hyp_text __debug_restore_state(struct kvm_vcpu *vcpu,
  90                                       struct kvm_guest_debug_arch *dbg,
  91                                       struct kvm_cpu_context *ctxt)
  92 {
  93         u64 aa64dfr0;
  94         int brps, wrps;
  95
  96         if (!(vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY))
  97                 return;
  98
  99         aa64dfr0 = read_sysreg(id_aa64dfr0_el1);
 100
 101         brps = (aa64dfr0 >> 12) & 0xf;
 102         wrps = (aa64dfr0 >> 20) & 0xf;
 103
 104         restore_debug(dbg->dbg_bcr, dbgbcr, brps);
 105         restore_debug(dbg->dbg_bvr, dbgbvr, brps);
 106         restore_debug(dbg->dbg_wcr, dbgwcr, wrps);
 107         restore_debug(dbg->dbg_wvr, dbgwvr, wrps);
 108
 109         write_sysreg(ctxt->sys_regs[MDCCINT_EL1], mdccint_el1);
 110 }
 111
 112 void __hyp_text __debug_cond_save_host_state(struct kvm_vcpu *vcpu)
 113 {
 114         /* If any of KDE, MDE or KVM_ARM64_DEBUG_DIRTY is set, perform
 115          * a full save/restore cycle. */
 116         if ((vcpu->arch.ctxt.sys_regs[MDSCR_EL1] & DBG_MDSCR_KDE) ||
 117             (vcpu->arch.ctxt.sys_regs[MDSCR_EL1] & DBG_MDSCR_MDE))
 118                 vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY;
 119
 120         __debug_save_state(vcpu, &vcpu->arch.host_debug_state,
 121                            kern_hyp_va(vcpu->arch.host_cpu_context));
 122 }
 123
 124 void __hyp_text __debug_cond_restore_host_state(struct kvm_vcpu *vcpu)
 125 {
 126         __debug_restore_state(vcpu, &vcpu->arch.host_debug_state,
 127                               kern_hyp_va(vcpu->arch.host_cpu_context));
 128
 129         if (vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY)
 130                 vcpu->arch.debug_flags &= ~KVM_ARM64_DEBUG_DIRTY;
 131 }
 132
 133 static u32 __hyp_text __debug_read_mdcr_el2(void)
 134 {
 135         return read_sysreg(mdcr_el2);
 136 }
 137
 138 __alias(__debug_read_mdcr_el2) u32 __kvm_get_mdcr_el2(void);