arch/arm64/kvm/hyp/vgic-v3-sr.c

   1 /*
   2  * Copyright (C) 2012-2015 - 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/irqchip/arm-gic-v3.h>
  20 #include <linux/kvm_host.h>
  21
  22 #include <asm/kvm_hyp.h>
  23
  24 #define vtr_to_max_lr_idx(v)            ((v) & 0xf)
  25 #define vtr_to_nr_pri_bits(v)           (((u32)(v) >> 29) + 1)
  26
  27 static u64 __hyp_text __gic_v3_get_lr(unsigned int lr)
  28 {
  29         switch (lr & 0xf) {
  30         case 0:
  31                 return read_gicreg(ICH_LR0_EL2);
  32         case 1:
  33                 return read_gicreg(ICH_LR1_EL2);
  34         case 2:
  35                 return read_gicreg(ICH_LR2_EL2);
  36         case 3:
  37                 return read_gicreg(ICH_LR3_EL2);
  38         case 4:
  39                 return read_gicreg(ICH_LR4_EL2);
  40         case 5:
  41                 return read_gicreg(ICH_LR5_EL2);
  42         case 6:
  43                 return read_gicreg(ICH_LR6_EL2);
  44         case 7:
  45                 return read_gicreg(ICH_LR7_EL2);
  46         case 8:
  47                 return read_gicreg(ICH_LR8_EL2);
  48         case 9:
  49                 return read_gicreg(ICH_LR9_EL2);
  50         case 10:
  51                 return read_gicreg(ICH_LR10_EL2);
  52         case 11:
  53                 return read_gicreg(ICH_LR11_EL2);
  54         case 12:
  55                 return read_gicreg(ICH_LR12_EL2);
  56         case 13:
  57                 return read_gicreg(ICH_LR13_EL2);
  58         case 14:
  59                 return read_gicreg(ICH_LR14_EL2);
  60         case 15:
  61                 return read_gicreg(ICH_LR15_EL2);
  62         }
  63
  64         unreachable();
  65 }
  66
  67 static void __hyp_text __gic_v3_set_lr(u64 val, int lr)
  68 {
  69         switch (lr & 0xf) {
  70         case 0:
  71                 write_gicreg(val, ICH_LR0_EL2);
  72                 break;
  73         case 1:
  74                 write_gicreg(val, ICH_LR1_EL2);
  75                 break;
  76         case 2:
  77                 write_gicreg(val, ICH_LR2_EL2);
  78                 break;
  79         case 3:
  80                 write_gicreg(val, ICH_LR3_EL2);
  81                 break;
  82         case 4:
  83                 write_gicreg(val, ICH_LR4_EL2);
  84                 break;
  85         case 5:
  86                 write_gicreg(val, ICH_LR5_EL2);
  87                 break;
  88         case 6:
  89                 write_gicreg(val, ICH_LR6_EL2);
  90                 break;
  91         case 7:
  92                 write_gicreg(val, ICH_LR7_EL2);
  93                 break;
  94         case 8:
  95                 write_gicreg(val, ICH_LR8_EL2);
  96                 break;
  97         case 9:
  98                 write_gicreg(val, ICH_LR9_EL2);
  99                 break;
 100         case 10:
 101                 write_gicreg(val, ICH_LR10_EL2);
 102                 break;
 103         case 11:
 104                 write_gicreg(val, ICH_LR11_EL2);
 105                 break;
 106         case 12:
 107                 write_gicreg(val, ICH_LR12_EL2);
 108                 break;
 109         case 13:
 110                 write_gicreg(val, ICH_LR13_EL2);
 111                 break;
 112         case 14:
 113                 write_gicreg(val, ICH_LR14_EL2);
 114                 break;
 115         case 15:
 116                 write_gicreg(val, ICH_LR15_EL2);
 117                 break;
 118         }
 119 }
 120
 121 static void __hyp_text save_maint_int_state(struct kvm_vcpu *vcpu, int nr_lr)
 122 {
 123         struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
 124         int i;
 125         bool expect_mi;
 126
 127         expect_mi = !!(cpu_if->vgic_hcr & ICH_HCR_UIE);
 128
 129         for (i = 0; i < nr_lr; i++) {
 130                 if (!(vcpu->arch.vgic_cpu.live_lrs & (1UL << i)))
 131                                 continue;
 132
 133                 expect_mi |= (!(cpu_if->vgic_lr[i] & ICH_LR_HW) &&
 134                               (cpu_if->vgic_lr[i] & ICH_LR_EOI));
 135         }
 136
 137         if (expect_mi) {
 138                 cpu_if->vgic_misr  = read_gicreg(ICH_MISR_EL2);
 139
 140                 if (cpu_if->vgic_misr & ICH_MISR_EOI)
 141                         cpu_if->vgic_eisr = read_gicreg(ICH_EISR_EL2);
 142                 else
 143                         cpu_if->vgic_eisr = 0;
 144         } else {
 145                 cpu_if->vgic_misr = 0;
 146                 cpu_if->vgic_eisr = 0;
 147         }
 148 }
 149
 150 void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu)
 151 {
 152         struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
 153         u64 val;
 154
 155         /*
 156          * Make sure stores to the GIC via the memory mapped interface
 157          * are now visible to the system register interface.
 158          */
 159         if (!cpu_if->vgic_sre)
 160                 dsb(st);
 161
 162         cpu_if->vgic_vmcr  = read_gicreg(ICH_VMCR_EL2);
 163
 164         if (vcpu->arch.vgic_cpu.live_lrs) {
 165                 int i;
 166                 u32 max_lr_idx, nr_pri_bits;
 167
 168                 cpu_if->vgic_elrsr = read_gicreg(ICH_ELSR_EL2);
 169
 170                 write_gicreg(0, ICH_HCR_EL2);
 171                 val = read_gicreg(ICH_VTR_EL2);
 172                 max_lr_idx = vtr_to_max_lr_idx(val);
 173                 nr_pri_bits = vtr_to_nr_pri_bits(val);
 174
 175                 save_maint_int_state(vcpu, max_lr_idx + 1);
 176
 177                 for (i = 0; i <= max_lr_idx; i++) {
 178                         if (!(vcpu->arch.vgic_cpu.live_lrs & (1UL << i)))
 179                                 continue;
 180
 181                         if (cpu_if->vgic_elrsr & (1 << i))
 182                                 cpu_if->vgic_lr[i] &= ~ICH_LR_STATE;
 183                         else
 184                                 cpu_if->vgic_lr[i] = __gic_v3_get_lr(i);
 185
 186                         __gic_v3_set_lr(0, i);
 187                 }
 188
 189                 switch (nr_pri_bits) {
 190                 case 7:
 191                         cpu_if->vgic_ap0r[3] = read_gicreg(ICH_AP0R3_EL2);
 192                         cpu_if->vgic_ap0r[2] = read_gicreg(ICH_AP0R2_EL2);
 193                 case 6:
 194                         cpu_if->vgic_ap0r[1] = read_gicreg(ICH_AP0R1_EL2);
 195                 default:
 196                         cpu_if->vgic_ap0r[0] = read_gicreg(ICH_AP0R0_EL2);
 197                 }
 198
 199                 switch (nr_pri_bits) {
 200                 case 7:
 201                         cpu_if->vgic_ap1r[3] = read_gicreg(ICH_AP1R3_EL2);
 202                         cpu_if->vgic_ap1r[2] = read_gicreg(ICH_AP1R2_EL2);
 203                 case 6:
 204                         cpu_if->vgic_ap1r[1] = read_gicreg(ICH_AP1R1_EL2);
 205                 default:
 206                         cpu_if->vgic_ap1r[0] = read_gicreg(ICH_AP1R0_EL2);
 207                 }
 208
 209                 vcpu->arch.vgic_cpu.live_lrs = 0;
 210         } else {
 211                 cpu_if->vgic_misr  = 0;
 212                 cpu_if->vgic_eisr  = 0;
 213                 cpu_if->vgic_elrsr = 0xffff;
 214                 cpu_if->vgic_ap0r[0] = 0;
 215                 cpu_if->vgic_ap0r[1] = 0;
 216                 cpu_if->vgic_ap0r[2] = 0;
 217                 cpu_if->vgic_ap0r[3] = 0;
 218                 cpu_if->vgic_ap1r[0] = 0;
 219                 cpu_if->vgic_ap1r[1] = 0;
 220                 cpu_if->vgic_ap1r[2] = 0;
 221                 cpu_if->vgic_ap1r[3] = 0;
 222         }
 223
 224         val = read_gicreg(ICC_SRE_EL2);
 225         write_gicreg(val | ICC_SRE_EL2_ENABLE, ICC_SRE_EL2);
 226
 227         if (!cpu_if->vgic_sre) {
 228                 /* Make sure ENABLE is set at EL2 before setting SRE at EL1 */
 229                 isb();
 230                 write_gicreg(1, ICC_SRE_EL1);
 231         }
 232 }
 233
 234 void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu)
 235 {
 236         struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
 237         u64 val;
 238         u32 max_lr_idx, nr_pri_bits;
 239         u16 live_lrs = 0;
 240         int i;
 241
 242         /*
 243          * VFIQEn is RES1 if ICC_SRE_EL1.SRE is 1. This causes a
 244          * Group0 interrupt (as generated in GICv2 mode) to be
 245          * delivered as a FIQ to the guest, with potentially fatal
 246          * consequences. So we must make sure that ICC_SRE_EL1 has
 247          * been actually programmed with the value we want before
 248          * starting to mess with the rest of the GIC.
 249          */
 250         if (!cpu_if->vgic_sre) {
 251                 write_gicreg(0, ICC_SRE_EL1);
 252                 isb();
 253         }
 254
 255         val = read_gicreg(ICH_VTR_EL2);
 256         max_lr_idx = vtr_to_max_lr_idx(val);
 257         nr_pri_bits = vtr_to_nr_pri_bits(val);
 258
 259         for (i = 0; i <= max_lr_idx; i++) {
 260                 if (cpu_if->vgic_lr[i] & ICH_LR_STATE)
 261                         live_lrs |= (1 << i);
 262         }
 263
 264         write_gicreg(cpu_if->vgic_vmcr, ICH_VMCR_EL2);
 265
 266         if (live_lrs) {
 267                 write_gicreg(cpu_if->vgic_hcr, ICH_HCR_EL2);
 268
 269                 switch (nr_pri_bits) {
 270                 case 7:
 271                         write_gicreg(cpu_if->vgic_ap0r[3], ICH_AP0R3_EL2);
 272                         write_gicreg(cpu_if->vgic_ap0r[2], ICH_AP0R2_EL2);
 273                 case 6:
 274                         write_gicreg(cpu_if->vgic_ap0r[1], ICH_AP0R1_EL2);
 275                 default:
 276                         write_gicreg(cpu_if->vgic_ap0r[0], ICH_AP0R0_EL2);
 277                 }
 278
 279                 switch (nr_pri_bits) {
 280                 case 7:
 281                         write_gicreg(cpu_if->vgic_ap1r[3], ICH_AP1R3_EL2);
 282                         write_gicreg(cpu_if->vgic_ap1r[2], ICH_AP1R2_EL2);
 283                 case 6:
 284                         write_gicreg(cpu_if->vgic_ap1r[1], ICH_AP1R1_EL2);
 285                 default:
 286                         write_gicreg(cpu_if->vgic_ap1r[0], ICH_AP1R0_EL2);
 287                 }
 288
 289                 for (i = 0; i <= max_lr_idx; i++) {
 290                         if (!(live_lrs & (1 << i)))
 291                                 continue;
 292
 293                         __gic_v3_set_lr(cpu_if->vgic_lr[i], i);
 294                 }
 295         }
 296
 297         /*
 298          * Ensures that the above will have reached the
 299          * (re)distributors. This ensure the guest will read the
 300          * correct values from the memory-mapped interface.
 301          */
 302         if (!cpu_if->vgic_sre) {
 303                 isb();
 304                 dsb(sy);
 305         }
 306         vcpu->arch.vgic_cpu.live_lrs = live_lrs;
 307
 308         /*
 309          * Prevent the guest from touching the GIC system registers if
 310          * SRE isn't enabled for GICv3 emulation.
 311          */
 312         write_gicreg(read_gicreg(ICC_SRE_EL2) & ~ICC_SRE_EL2_ENABLE,
 313                      ICC_SRE_EL2);
 314 }
 315
 316 void __hyp_text __vgic_v3_init_lrs(void)
 317 {
 318         int max_lr_idx = vtr_to_max_lr_idx(read_gicreg(ICH_VTR_EL2));
 319         int i;
 320
 321         for (i = 0; i <= max_lr_idx; i++)
 322                 __gic_v3_set_lr(0, i);
 323 }
 324
 325 u64 __hyp_text __vgic_v3_get_ich_vtr_el2(void)
 326 {
 327         return read_gicreg(ICH_VTR_EL2);
 328 }