arch/arm64/kvm/vgic-sys-reg-v3.c

   1 /*
   2  * VGIC system registers handling functions for AArch64 mode
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <linux/irqchip/arm-gic-v3.h>
  15 #include <linux/kvm.h>
  16 #include <linux/kvm_host.h>
  17 #include <asm/kvm_emulate.h>
  18 #include "vgic.h"
  19 #include "sys_regs.h"
  20
  21 static bool access_gic_ctlr(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
  22                             const struct sys_reg_desc *r)
  23 {
  24         u32 host_pri_bits, host_id_bits, host_seis, host_a3v, seis, a3v;
  25         struct vgic_cpu *vgic_v3_cpu = &vcpu->arch.vgic_cpu;
  26         struct vgic_vmcr vmcr;
  27         u64 val;
  28
  29         vgic_get_vmcr(vcpu, &vmcr);
  30         if (p->is_write) {
  31                 val = p->regval;
  32
  33                 /*
  34                  * Disallow restoring VM state if not supported by this
  35                  * hardware.
  36                  */
  37                 host_pri_bits = ((val & ICC_CTLR_EL1_PRI_BITS_MASK) >>
  38                                  ICC_CTLR_EL1_PRI_BITS_SHIFT) + 1;
  39                 if (host_pri_bits > vgic_v3_cpu->num_pri_bits)
  40                         return false;
  41
  42                 vgic_v3_cpu->num_pri_bits = host_pri_bits;
  43
  44                 host_id_bits = (val & ICC_CTLR_EL1_ID_BITS_MASK) >>
  45                                 ICC_CTLR_EL1_ID_BITS_SHIFT;
  46                 if (host_id_bits > vgic_v3_cpu->num_id_bits)
  47                         return false;
  48
  49                 vgic_v3_cpu->num_id_bits = host_id_bits;
  50
  51                 host_seis = ((kvm_vgic_global_state.ich_vtr_el2 &
  52                              ICH_VTR_SEIS_MASK) >> ICH_VTR_SEIS_SHIFT);
  53                 seis = (val & ICC_CTLR_EL1_SEIS_MASK) >>
  54                         ICC_CTLR_EL1_SEIS_SHIFT;
  55                 if (host_seis != seis)
  56                         return false;
  57
  58                 host_a3v = ((kvm_vgic_global_state.ich_vtr_el2 &
  59                             ICH_VTR_A3V_MASK) >> ICH_VTR_A3V_SHIFT);
  60                 a3v = (val & ICC_CTLR_EL1_A3V_MASK) >> ICC_CTLR_EL1_A3V_SHIFT;
  61                 if (host_a3v != a3v)
  62                         return false;
  63
  64                 /*
  65                  * Here set VMCR.CTLR in ICC_CTLR_EL1 layout.
  66                  * The vgic_set_vmcr() will convert to ICH_VMCR layout.
  67                  */
  68                 vmcr.cbpr = (val & ICC_CTLR_EL1_CBPR_MASK) >> ICC_CTLR_EL1_CBPR_SHIFT;
  69                 vmcr.eoim = (val & ICC_CTLR_EL1_EOImode_MASK) >> ICC_CTLR_EL1_EOImode_SHIFT;
  70                 vgic_set_vmcr(vcpu, &vmcr);
  71         } else {
  72                 val = 0;
  73                 val |= (vgic_v3_cpu->num_pri_bits - 1) <<
  74                         ICC_CTLR_EL1_PRI_BITS_SHIFT;
  75                 val |= vgic_v3_cpu->num_id_bits << ICC_CTLR_EL1_ID_BITS_SHIFT;
  76                 val |= ((kvm_vgic_global_state.ich_vtr_el2 &
  77                         ICH_VTR_SEIS_MASK) >> ICH_VTR_SEIS_SHIFT) <<
  78                         ICC_CTLR_EL1_SEIS_SHIFT;
  79                 val |= ((kvm_vgic_global_state.ich_vtr_el2 &
  80                         ICH_VTR_A3V_MASK) >> ICH_VTR_A3V_SHIFT) <<
  81                         ICC_CTLR_EL1_A3V_SHIFT;
  82                 /*
  83                  * The VMCR.CTLR value is in ICC_CTLR_EL1 layout.
  84                  * Extract it directly using ICC_CTLR_EL1 reg definitions.
  85                  */
  86                 val |= (vmcr.cbpr << ICC_CTLR_EL1_CBPR_SHIFT) & ICC_CTLR_EL1_CBPR_MASK;
  87                 val |= (vmcr.eoim << ICC_CTLR_EL1_EOImode_SHIFT) & ICC_CTLR_EL1_EOImode_MASK;
  88
  89                 p->regval = val;
  90         }
  91
  92         return true;
  93 }
  94
  95 static bool access_gic_pmr(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
  96                            const struct sys_reg_desc *r)
  97 {
  98         struct vgic_vmcr vmcr;
  99
 100         vgic_get_vmcr(vcpu, &vmcr);
 101         if (p->is_write) {
 102                 vmcr.pmr = (p->regval & ICC_PMR_EL1_MASK) >> ICC_PMR_EL1_SHIFT;
 103                 vgic_set_vmcr(vcpu, &vmcr);
 104         } else {
 105                 p->regval = (vmcr.pmr << ICC_PMR_EL1_SHIFT) & ICC_PMR_EL1_MASK;
 106         }
 107
 108         return true;
 109 }
 110
 111 static bool access_gic_bpr0(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 112                             const struct sys_reg_desc *r)
 113 {
 114         struct vgic_vmcr vmcr;
 115
 116         vgic_get_vmcr(vcpu, &vmcr);
 117         if (p->is_write) {
 118                 vmcr.bpr = (p->regval & ICC_BPR0_EL1_MASK) >>
 119                             ICC_BPR0_EL1_SHIFT;
 120                 vgic_set_vmcr(vcpu, &vmcr);
 121         } else {
 122                 p->regval = (vmcr.bpr << ICC_BPR0_EL1_SHIFT) &
 123                              ICC_BPR0_EL1_MASK;
 124         }
 125
 126         return true;
 127 }
 128
 129 static bool access_gic_bpr1(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 130                             const struct sys_reg_desc *r)
 131 {
 132         struct vgic_vmcr vmcr;
 133
 134         if (!p->is_write)
 135                 p->regval = 0;
 136
 137         vgic_get_vmcr(vcpu, &vmcr);
 138         if (!vmcr.cbpr) {
 139                 if (p->is_write) {
 140                         vmcr.abpr = (p->regval & ICC_BPR1_EL1_MASK) >>
 141                                      ICC_BPR1_EL1_SHIFT;
 142                         vgic_set_vmcr(vcpu, &vmcr);
 143                 } else {
 144                         p->regval = (vmcr.abpr << ICC_BPR1_EL1_SHIFT) &
 145                                      ICC_BPR1_EL1_MASK;
 146                 }
 147         } else {
 148                 if (!p->is_write)
 149                         p->regval = min((vmcr.bpr + 1), 7U);
 150         }
 151
 152         return true;
 153 }
 154
 155 static bool access_gic_grpen0(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 156                               const struct sys_reg_desc *r)
 157 {
 158         struct vgic_vmcr vmcr;
 159
 160         vgic_get_vmcr(vcpu, &vmcr);
 161         if (p->is_write) {
 162                 vmcr.grpen0 = (p->regval & ICC_IGRPEN0_EL1_MASK) >>
 163                                ICC_IGRPEN0_EL1_SHIFT;
 164                 vgic_set_vmcr(vcpu, &vmcr);
 165         } else {
 166                 p->regval = (vmcr.grpen0 << ICC_IGRPEN0_EL1_SHIFT) &
 167                              ICC_IGRPEN0_EL1_MASK;
 168         }
 169
 170         return true;
 171 }
 172
 173 static bool access_gic_grpen1(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 174                               const struct sys_reg_desc *r)
 175 {
 176         struct vgic_vmcr vmcr;
 177
 178         vgic_get_vmcr(vcpu, &vmcr);
 179         if (p->is_write) {
 180                 vmcr.grpen1 = (p->regval & ICC_IGRPEN1_EL1_MASK) >>
 181                                ICC_IGRPEN1_EL1_SHIFT;
 182                 vgic_set_vmcr(vcpu, &vmcr);
 183         } else {
 184                 p->regval = (vmcr.grpen1 << ICC_IGRPEN1_EL1_SHIFT) &
 185                              ICC_IGRPEN1_EL1_MASK;
 186         }
 187
 188         return true;
 189 }
 190
 191 static void vgic_v3_access_apr_reg(struct kvm_vcpu *vcpu,
 192                                    struct sys_reg_params *p, u8 apr, u8 idx)
 193 {
 194         struct vgic_v3_cpu_if *vgicv3 = &vcpu->arch.vgic_cpu.vgic_v3;
 195         uint32_t *ap_reg;
 196
 197         if (apr)
 198                 ap_reg = &vgicv3->vgic_ap1r[idx];
 199         else
 200                 ap_reg = &vgicv3->vgic_ap0r[idx];
 201
 202         if (p->is_write)
 203                 *ap_reg = p->regval;
 204         else
 205                 p->regval = *ap_reg;
 206 }
 207
 208 static bool access_gic_aprn(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 209                             const struct sys_reg_desc *r, u8 apr)
 210 {
 211         struct vgic_cpu *vgic_v3_cpu = &vcpu->arch.vgic_cpu;
 212         u8 idx = r->Op2 & 3;
 213
 214         /*
 215          * num_pri_bits are initialized with HW supported values.
 216          * We can rely safely on num_pri_bits even if VM has not
 217          * restored ICC_CTLR_EL1 before restoring APnR registers.
 218          */
 219         switch (vgic_v3_cpu->num_pri_bits) {
 220         case 7:
 221                 vgic_v3_access_apr_reg(vcpu, p, apr, idx);
 222                 break;
 223         case 6:
 224                 if (idx > 1)
 225                         goto err;
 226                 vgic_v3_access_apr_reg(vcpu, p, apr, idx);
 227                 break;
 228         default:
 229                 if (idx > 0)
 230                         goto err;
 231                 vgic_v3_access_apr_reg(vcpu, p, apr, idx);
 232         }
 233
 234         return true;
 235 err:
 236         if (!p->is_write)
 237                 p->regval = 0;
 238
 239         return false;
 240 }
 241
 242 static bool access_gic_ap0r(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 243                             const struct sys_reg_desc *r)
 244
 245 {
 246         return access_gic_aprn(vcpu, p, r, 0);
 247 }
 248
 249 static bool access_gic_ap1r(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 250                             const struct sys_reg_desc *r)
 251 {
 252         return access_gic_aprn(vcpu, p, r, 1);
 253 }
 254
 255 static bool access_gic_sre(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 256                            const struct sys_reg_desc *r)
 257 {
 258         struct vgic_v3_cpu_if *vgicv3 = &vcpu->arch.vgic_cpu.vgic_v3;
 259
 260         /* Validate SRE bit */
 261         if (p->is_write) {
 262                 if (!(p->regval & ICC_SRE_EL1_SRE))
 263                         return false;
 264         } else {
 265                 p->regval = vgicv3->vgic_sre;
 266         }
 267
 268         return true;
 269 }
 270 static const struct sys_reg_desc gic_v3_icc_reg_descs[] = {
 271         { SYS_DESC(SYS_ICC_PMR_EL1), access_gic_pmr },
 272         { SYS_DESC(SYS_ICC_BPR0_EL1), access_gic_bpr0 },
 273         { SYS_DESC(SYS_ICC_AP0R0_EL1), access_gic_ap0r },
 274         { SYS_DESC(SYS_ICC_AP0R1_EL1), access_gic_ap0r },
 275         { SYS_DESC(SYS_ICC_AP0R2_EL1), access_gic_ap0r },
 276         { SYS_DESC(SYS_ICC_AP0R3_EL1), access_gic_ap0r },
 277         { SYS_DESC(SYS_ICC_AP1R0_EL1), access_gic_ap1r },
 278         { SYS_DESC(SYS_ICC_AP1R1_EL1), access_gic_ap1r },
 279         { SYS_DESC(SYS_ICC_AP1R2_EL1), access_gic_ap1r },
 280         { SYS_DESC(SYS_ICC_AP1R3_EL1), access_gic_ap1r },
 281         { SYS_DESC(SYS_ICC_BPR1_EL1), access_gic_bpr1 },
 282         { SYS_DESC(SYS_ICC_CTLR_EL1), access_gic_ctlr },
 283         { SYS_DESC(SYS_ICC_SRE_EL1), access_gic_sre },
 284         { SYS_DESC(SYS_ICC_IGRPEN0_EL1), access_gic_grpen0 },
 285         { SYS_DESC(SYS_ICC_IGRPEN1_EL1), access_gic_grpen1 },
 286 };
 287
 288 int vgic_v3_has_cpu_sysregs_attr(struct kvm_vcpu *vcpu, bool is_write, u64 id,
 289                                 u64 *reg)
 290 {
 291         struct sys_reg_params params;
 292         u64 sysreg = (id & KVM_DEV_ARM_VGIC_SYSREG_MASK) | KVM_REG_SIZE_U64;
 293
 294         params.regval = *reg;
 295         params.is_write = is_write;
 296         params.is_aarch32 = false;
 297         params.is_32bit = false;
 298
 299         if (find_reg_by_id(sysreg, &params, gic_v3_icc_reg_descs,
 300                               ARRAY_SIZE(gic_v3_icc_reg_descs)))
 301                 return 0;
 302
 303         return -ENXIO;
 304 }
 305
 306 int vgic_v3_cpu_sysregs_uaccess(struct kvm_vcpu *vcpu, bool is_write, u64 id,
 307                                 u64 *reg)
 308 {
 309         struct sys_reg_params params;
 310         const struct sys_reg_desc *r;
 311         u64 sysreg = (id & KVM_DEV_ARM_VGIC_SYSREG_MASK) | KVM_REG_SIZE_U64;
 312
 313         if (is_write)
 314                 params.regval = *reg;
 315         params.is_write = is_write;
 316         params.is_aarch32 = false;
 317         params.is_32bit = false;
 318
 319         r = find_reg_by_id(sysreg, &params, gic_v3_icc_reg_descs,
 320                            ARRAY_SIZE(gic_v3_icc_reg_descs));
 321         if (!r)
 322                 return -ENXIO;
 323
 324         if (!r->access(vcpu, &params, r))
 325                 return -EINVAL;
 326
 327         if (!is_write)
 328                 *reg = params.regval;
 329
 330         return 0;
 331 }