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