linux/arch/powerpc/kvm/e500.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) 2008-2011 Freescale Semiconductor, Inc. All rights reserved.
   4 *
   5 * Author: Yu Liu, <yu.liu@freescale.com>
   6 *
   7 * Description:
   8 * This file is derived from arch/powerpc/kvm/44x.c,
   9 * by Hollis Blanchard <hollisb@us.ibm.com>.
  10 */
  11
  12#include <linux/kvm_host.h>
  13#include <linux/slab.h>
  14#include <linux/err.h>
  15#include <linux/export.h>
  16#include <linux/module.h>
  17#include <linux/miscdevice.h>
  18
  19#include <asm/reg.h>
  20#include <asm/cputable.h>
  21#include <asm/kvm_ppc.h>
  22
  23#include "../mm/mmu_decl.h"
  24#include "booke.h"
  25#include "e500.h"
  26
  27struct id {
  28        unsigned long val;
  29        struct id **pentry;
  30};
  31
  32#define NUM_TIDS 256
  33
  34/*
  35 * This table provide mappings from:
  36 * (guestAS,guestTID,guestPR) --> ID of physical cpu
  37 * guestAS      [0..1]
  38 * guestTID     [0..255]
  39 * guestPR      [0..1]
  40 * ID           [1..255]
  41 * Each vcpu keeps one vcpu_id_table.
  42 */
  43struct vcpu_id_table {
  44        struct id id[2][NUM_TIDS][2];
  45};
  46
  47/*
  48 * This table provide reversed mappings of vcpu_id_table:
  49 * ID --> address of vcpu_id_table item.
  50 * Each physical core has one pcpu_id_table.
  51 */
  52struct pcpu_id_table {
  53        struct id *entry[NUM_TIDS];
  54};
  55
  56static DEFINE_PER_CPU(struct pcpu_id_table, pcpu_sids);
  57
  58/* This variable keeps last used shadow ID on local core.
  59 * The valid range of shadow ID is [1..255] */
  60static DEFINE_PER_CPU(unsigned long, pcpu_last_used_sid);
  61
  62/*
  63 * Allocate a free shadow id and setup a valid sid mapping in given entry.
  64 * A mapping is only valid when vcpu_id_table and pcpu_id_table are match.
  65 *
  66 * The caller must have preemption disabled, and keep it that way until
  67 * it has finished with the returned shadow id (either written into the
  68 * TLB or arch.shadow_pid, or discarded).
  69 */
  70static inline int local_sid_setup_one(struct id *entry)
  71{
  72        unsigned long sid;
  73        int ret = -1;
  74
  75        sid = __this_cpu_inc_return(pcpu_last_used_sid);
  76        if (sid < NUM_TIDS) {
  77                __this_cpu_write(pcpu_sids.entry[sid], entry);
  78                entry->val = sid;
  79                entry->pentry = this_cpu_ptr(&pcpu_sids.entry[sid]);
  80                ret = sid;
  81        }
  82
  83        /*
  84         * If sid == NUM_TIDS, we've run out of sids.  We return -1, and
  85         * the caller will invalidate everything and start over.
  86         *
  87         * sid > NUM_TIDS indicates a race, which we disable preemption to
  88         * avoid.
  89         */
  90        WARN_ON(sid > NUM_TIDS);
  91
  92        return ret;
  93}
  94
  95/*
  96 * Check if given entry contain a valid shadow id mapping.
  97 * An ID mapping is considered valid only if
  98 * both vcpu and pcpu know this mapping.
  99 *
 100 * The caller must have preemption disabled, and keep it that way until
 101 * it has finished with the returned shadow id (either written into the
 102 * TLB or arch.shadow_pid, or discarded).
 103 */
 104static inline int local_sid_lookup(struct id *entry)
 105{
 106        if (entry && entry->val != 0 &&
 107            __this_cpu_read(pcpu_sids.entry[entry->val]) == entry &&
 108            entry->pentry == this_cpu_ptr(&pcpu_sids.entry[entry->val]))
 109                return entry->val;
 110        return -1;
 111}
 112
 113/* Invalidate all id mappings on local core -- call with preempt disabled */
 114static inline void local_sid_destroy_all(void)
 115{
 116        __this_cpu_write(pcpu_last_used_sid, 0);
 117        memset(this_cpu_ptr(&pcpu_sids), 0, sizeof(pcpu_sids));
 118}
 119
 120static void *kvmppc_e500_id_table_alloc(struct kvmppc_vcpu_e500 *vcpu_e500)
 121{
 122        vcpu_e500->idt = kzalloc(sizeof(struct vcpu_id_table), GFP_KERNEL);
 123        return vcpu_e500->idt;
 124}
 125
 126static void kvmppc_e500_id_table_free(struct kvmppc_vcpu_e500 *vcpu_e500)
 127{
 128        kfree(vcpu_e500->idt);
 129        vcpu_e500->idt = NULL;
 130}
 131
 132/* Map guest pid to shadow.
 133 * We use PID to keep shadow of current guest non-zero PID,
 134 * and use PID1 to keep shadow of guest zero PID.
 135 * So that guest tlbe with TID=0 can be accessed at any time */
 136static void kvmppc_e500_recalc_shadow_pid(struct kvmppc_vcpu_e500 *vcpu_e500)
 137{
 138        preempt_disable();
 139        vcpu_e500->vcpu.arch.shadow_pid = kvmppc_e500_get_sid(vcpu_e500,
 140                        get_cur_as(&vcpu_e500->vcpu),
 141                        get_cur_pid(&vcpu_e500->vcpu),
 142                        get_cur_pr(&vcpu_e500->vcpu), 1);
 143        vcpu_e500->vcpu.arch.shadow_pid1 = kvmppc_e500_get_sid(vcpu_e500,
 144                        get_cur_as(&vcpu_e500->vcpu), 0,
 145                        get_cur_pr(&vcpu_e500->vcpu), 1);
 146        preempt_enable();
 147}
 148
 149/* Invalidate all mappings on vcpu */
 150static void kvmppc_e500_id_table_reset_all(struct kvmppc_vcpu_e500 *vcpu_e500)
 151{
 152        memset(vcpu_e500->idt, 0, sizeof(struct vcpu_id_table));
 153
 154        /* Update shadow pid when mappings are changed */
 155        kvmppc_e500_recalc_shadow_pid(vcpu_e500);
 156}
 157
 158/* Invalidate one ID mapping on vcpu */
 159static inline void kvmppc_e500_id_table_reset_one(
 160                               struct kvmppc_vcpu_e500 *vcpu_e500,
 161                               int as, int pid, int pr)
 162{
 163        struct vcpu_id_table *idt = vcpu_e500->idt;
 164
 165        BUG_ON(as >= 2);
 166        BUG_ON(pid >= NUM_TIDS);
 167        BUG_ON(pr >= 2);
 168
 169        idt->id[as][pid][pr].val = 0;
 170        idt->id[as][pid][pr].pentry = NULL;
 171
 172        /* Update shadow pid when mappings are changed */
 173        kvmppc_e500_recalc_shadow_pid(vcpu_e500);
 174}
 175
 176/*
 177 * Map guest (vcpu,AS,ID,PR) to physical core shadow id.
 178 * This function first lookup if a valid mapping exists,
 179 * if not, then creates a new one.
 180 *
 181 * The caller must have preemption disabled, and keep it that way until
 182 * it has finished with the returned shadow id (either written into the
 183 * TLB or arch.shadow_pid, or discarded).
 184 */
 185unsigned int kvmppc_e500_get_sid(struct kvmppc_vcpu_e500 *vcpu_e500,
 186                                 unsigned int as, unsigned int gid,
 187                                 unsigned int pr, int avoid_recursion)
 188{
 189        struct vcpu_id_table *idt = vcpu_e500->idt;
 190        int sid;
 191
 192        BUG_ON(as >= 2);
 193        BUG_ON(gid >= NUM_TIDS);
 194        BUG_ON(pr >= 2);
 195
 196        sid = local_sid_lookup(&idt->id[as][gid][pr]);
 197
 198        while (sid <= 0) {
 199                /* No mapping yet */
 200                sid = local_sid_setup_one(&idt->id[as][gid][pr]);
 201                if (sid <= 0) {
 202                        _tlbil_all();
 203                        local_sid_destroy_all();
 204                }
 205
 206                /* Update shadow pid when mappings are changed */
 207                if (!avoid_recursion)
 208                        kvmppc_e500_recalc_shadow_pid(vcpu_e500);
 209        }
 210
 211        return sid;
 212}
 213
 214unsigned int kvmppc_e500_get_tlb_stid(struct kvm_vcpu *vcpu,
 215                                      struct kvm_book3e_206_tlb_entry *gtlbe)
 216{
 217        return kvmppc_e500_get_sid(to_e500(vcpu), get_tlb_ts(gtlbe),
 218                                   get_tlb_tid(gtlbe), get_cur_pr(vcpu), 0);
 219}
 220
 221void kvmppc_set_pid(struct kvm_vcpu *vcpu, u32 pid)
 222{
 223        struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
 224
 225        if (vcpu->arch.pid != pid) {
 226                vcpu_e500->pid[0] = vcpu->arch.pid = pid;
 227                kvmppc_e500_recalc_shadow_pid(vcpu_e500);
 228        }
 229}
 230
 231/* gtlbe must not be mapped by more than one host tlbe */
 232void kvmppc_e500_tlbil_one(struct kvmppc_vcpu_e500 *vcpu_e500,
 233                           struct kvm_book3e_206_tlb_entry *gtlbe)
 234{
 235        struct vcpu_id_table *idt = vcpu_e500->idt;
 236        unsigned int pr, tid, ts;
 237        int pid;
 238        u32 val, eaddr;
 239        unsigned long flags;
 240
 241        ts = get_tlb_ts(gtlbe);
 242        tid = get_tlb_tid(gtlbe);
 243
 244        preempt_disable();
 245
 246        /* One guest ID may be mapped to two shadow IDs */
 247        for (pr = 0; pr < 2; pr++) {
 248                /*
 249                 * The shadow PID can have a valid mapping on at most one
 250                 * host CPU.  In the common case, it will be valid on this
 251                 * CPU, in which case we do a local invalidation of the
 252                 * specific address.
 253                 *
 254                 * If the shadow PID is not valid on the current host CPU,
 255                 * we invalidate the entire shadow PID.
 256                 */
 257                pid = local_sid_lookup(&idt->id[ts][tid][pr]);
 258                if (pid <= 0) {
 259                        kvmppc_e500_id_table_reset_one(vcpu_e500, ts, tid, pr);
 260                        continue;
 261                }
 262
 263                /*
 264                 * The guest is invalidating a 4K entry which is in a PID
 265                 * that has a valid shadow mapping on this host CPU.  We
 266                 * search host TLB to invalidate it's shadow TLB entry,
 267                 * similar to __tlbil_va except that we need to look in AS1.
 268                 */
 269                val = (pid << MAS6_SPID_SHIFT) | MAS6_SAS;
 270                eaddr = get_tlb_eaddr(gtlbe);
 271
 272                local_irq_save(flags);
 273
 274                mtspr(SPRN_MAS6, val);
 275                asm volatile("tlbsx 0, %[eaddr]" : : [eaddr] "r" (eaddr));
 276                val = mfspr(SPRN_MAS1);
 277                if (val & MAS1_VALID) {
 278                        mtspr(SPRN_MAS1, val & ~MAS1_VALID);
 279                        asm volatile("tlbwe");
 280                }
 281
 282                local_irq_restore(flags);
 283        }
 284
 285        preempt_enable();
 286}
 287
 288void kvmppc_e500_tlbil_all(struct kvmppc_vcpu_e500 *vcpu_e500)
 289{
 290        kvmppc_e500_id_table_reset_all(vcpu_e500);
 291}
 292
 293void kvmppc_mmu_msr_notify(struct kvm_vcpu *vcpu, u32 old_msr)
 294{
 295        /* Recalc shadow pid since MSR changes */
 296        kvmppc_e500_recalc_shadow_pid(to_e500(vcpu));
 297}
 298
 299static void kvmppc_core_vcpu_load_e500(struct kvm_vcpu *vcpu, int cpu)
 300{
 301        kvmppc_booke_vcpu_load(vcpu, cpu);
 302
 303        /* Shadow PID may be expired on local core */
 304        kvmppc_e500_recalc_shadow_pid(to_e500(vcpu));
 305}
 306
 307static void kvmppc_core_vcpu_put_e500(struct kvm_vcpu *vcpu)
 308{
 309#ifdef CONFIG_SPE
 310        if (vcpu->arch.shadow_msr & MSR_SPE)
 311                kvmppc_vcpu_disable_spe(vcpu);
 312#endif
 313
 314        kvmppc_booke_vcpu_put(vcpu);
 315}
 316
 317int kvmppc_core_check_processor_compat(void)
 318{
 319        int r;
 320
 321        if (strcmp(cur_cpu_spec->cpu_name, "e500v2") == 0)
 322                r = 0;
 323        else
 324                r = -ENOTSUPP;
 325
 326        return r;
 327}
 328
 329static void kvmppc_e500_tlb_setup(struct kvmppc_vcpu_e500 *vcpu_e500)
 330{
 331        struct kvm_book3e_206_tlb_entry *tlbe;
 332
 333        /* Insert large initial mapping for guest. */
 334        tlbe = get_entry(vcpu_e500, 1, 0);
 335        tlbe->mas1 = MAS1_VALID | MAS1_TSIZE(BOOK3E_PAGESZ_256M);
 336        tlbe->mas2 = 0;
 337        tlbe->mas7_3 = E500_TLB_SUPER_PERM_MASK;
 338
 339        /* 4K map for serial output. Used by kernel wrapper. */
 340        tlbe = get_entry(vcpu_e500, 1, 1);
 341        tlbe->mas1 = MAS1_VALID | MAS1_TSIZE(BOOK3E_PAGESZ_4K);
 342        tlbe->mas2 = (0xe0004500 & 0xFFFFF000) | MAS2_I | MAS2_G;
 343        tlbe->mas7_3 = (0xe0004500 & 0xFFFFF000) | E500_TLB_SUPER_PERM_MASK;
 344}
 345
 346int kvmppc_core_vcpu_setup(struct kvm_vcpu *vcpu)
 347{
 348        struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
 349
 350        kvmppc_e500_tlb_setup(vcpu_e500);
 351
 352        /* Registers init */
 353        vcpu->arch.pvr = mfspr(SPRN_PVR);
 354        vcpu_e500->svr = mfspr(SPRN_SVR);
 355
 356        vcpu->arch.cpu_type = KVM_CPU_E500V2;
 357
 358        return 0;
 359}
 360
 361static int kvmppc_core_get_sregs_e500(struct kvm_vcpu *vcpu,
 362                                      struct kvm_sregs *sregs)
 363{
 364        struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
 365
 366        sregs->u.e.features |= KVM_SREGS_E_ARCH206_MMU | KVM_SREGS_E_SPE |
 367                               KVM_SREGS_E_PM;
 368        sregs->u.e.impl_id = KVM_SREGS_E_IMPL_FSL;
 369
 370        sregs->u.e.impl.fsl.features = 0;
 371        sregs->u.e.impl.fsl.svr = vcpu_e500->svr;
 372        sregs->u.e.impl.fsl.hid0 = vcpu_e500->hid0;
 373        sregs->u.e.impl.fsl.mcar = vcpu_e500->mcar;
 374
 375        sregs->u.e.ivor_high[0] = vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_UNAVAIL];
 376        sregs->u.e.ivor_high[1] = vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_FP_DATA];
 377        sregs->u.e.ivor_high[2] = vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_FP_ROUND];
 378        sregs->u.e.ivor_high[3] =
 379                vcpu->arch.ivor[BOOKE_IRQPRIO_PERFORMANCE_MONITOR];
 380
 381        kvmppc_get_sregs_ivor(vcpu, sregs);
 382        kvmppc_get_sregs_e500_tlb(vcpu, sregs);
 383        return 0;
 384}
 385
 386static int kvmppc_core_set_sregs_e500(struct kvm_vcpu *vcpu,
 387                                      struct kvm_sregs *sregs)
 388{
 389        struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
 390        int ret;
 391
 392        if (sregs->u.e.impl_id == KVM_SREGS_E_IMPL_FSL) {
 393                vcpu_e500->svr = sregs->u.e.impl.fsl.svr;
 394                vcpu_e500->hid0 = sregs->u.e.impl.fsl.hid0;
 395                vcpu_e500->mcar = sregs->u.e.impl.fsl.mcar;
 396        }
 397
 398        ret = kvmppc_set_sregs_e500_tlb(vcpu, sregs);
 399        if (ret < 0)
 400                return ret;
 401
 402        if (!(sregs->u.e.features & KVM_SREGS_E_IVOR))
 403                return 0;
 404
 405        if (sregs->u.e.features & KVM_SREGS_E_SPE) {
 406                vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_UNAVAIL] =
 407                        sregs->u.e.ivor_high[0];
 408                vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_FP_DATA] =
 409                        sregs->u.e.ivor_high[1];
 410                vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_FP_ROUND] =
 411                        sregs->u.e.ivor_high[2];
 412        }
 413
 414        if (sregs->u.e.features & KVM_SREGS_E_PM) {
 415                vcpu->arch.ivor[BOOKE_IRQPRIO_PERFORMANCE_MONITOR] =
 416                        sregs->u.e.ivor_high[3];
 417        }
 418
 419        return kvmppc_set_sregs_ivor(vcpu, sregs);
 420}
 421
 422static int kvmppc_get_one_reg_e500(struct kvm_vcpu *vcpu, u64 id,
 423                                   union kvmppc_one_reg *val)
 424{
 425        int r = kvmppc_get_one_reg_e500_tlb(vcpu, id, val);
 426        return r;
 427}
 428
 429static int kvmppc_set_one_reg_e500(struct kvm_vcpu *vcpu, u64 id,
 430                                   union kvmppc_one_reg *val)
 431{
 432        int r = kvmppc_get_one_reg_e500_tlb(vcpu, id, val);
 433        return r;
 434}
 435
 436static struct kvm_vcpu *kvmppc_core_vcpu_create_e500(struct kvm *kvm,
 437                                                     unsigned int id)
 438{
 439        struct kvmppc_vcpu_e500 *vcpu_e500;
 440        struct kvm_vcpu *vcpu;
 441        int err;
 442
 443        BUILD_BUG_ON_MSG(offsetof(struct kvmppc_vcpu_e500, vcpu) != 0,
 444                "struct kvm_vcpu must be at offset 0 for arch usercopy region");
 445
 446        vcpu_e500 = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
 447        if (!vcpu_e500) {
 448                err = -ENOMEM;
 449                goto out;
 450        }
 451
 452        vcpu = &vcpu_e500->vcpu;
 453        err = kvm_vcpu_init(vcpu, kvm, id);
 454        if (err)
 455                goto free_vcpu;
 456
 457        if (kvmppc_e500_id_table_alloc(vcpu_e500) == NULL) {
 458                err = -ENOMEM;
 459                goto uninit_vcpu;
 460        }
 461
 462        err = kvmppc_e500_tlb_init(vcpu_e500);
 463        if (err)
 464                goto uninit_id;
 465
 466        vcpu->arch.shared = (void*)__get_free_page(GFP_KERNEL|__GFP_ZERO);
 467        if (!vcpu->arch.shared) {
 468                err = -ENOMEM;
 469                goto uninit_tlb;
 470        }
 471
 472        return vcpu;
 473
 474uninit_tlb:
 475        kvmppc_e500_tlb_uninit(vcpu_e500);
 476uninit_id:
 477        kvmppc_e500_id_table_free(vcpu_e500);
 478uninit_vcpu:
 479        kvm_vcpu_uninit(vcpu);
 480free_vcpu:
 481        kmem_cache_free(kvm_vcpu_cache, vcpu_e500);
 482out:
 483        return ERR_PTR(err);
 484}
 485
 486static void kvmppc_core_vcpu_free_e500(struct kvm_vcpu *vcpu)
 487{
 488        struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
 489
 490        free_page((unsigned long)vcpu->arch.shared);
 491        kvmppc_e500_tlb_uninit(vcpu_e500);
 492        kvmppc_e500_id_table_free(vcpu_e500);
 493        kvm_vcpu_uninit(vcpu);
 494        kmem_cache_free(kvm_vcpu_cache, vcpu_e500);
 495}
 496
 497static int kvmppc_core_init_vm_e500(struct kvm *kvm)
 498{
 499        return 0;
 500}
 501
 502static void kvmppc_core_destroy_vm_e500(struct kvm *kvm)
 503{
 504}
 505
 506static struct kvmppc_ops kvm_ops_e500 = {
 507        .get_sregs = kvmppc_core_get_sregs_e500,
 508        .set_sregs = kvmppc_core_set_sregs_e500,
 509        .get_one_reg = kvmppc_get_one_reg_e500,
 510        .set_one_reg = kvmppc_set_one_reg_e500,
 511        .vcpu_load   = kvmppc_core_vcpu_load_e500,
 512        .vcpu_put    = kvmppc_core_vcpu_put_e500,
 513        .vcpu_create = kvmppc_core_vcpu_create_e500,
 514        .vcpu_free   = kvmppc_core_vcpu_free_e500,
 515        .mmu_destroy  = kvmppc_mmu_destroy_e500,
 516        .init_vm = kvmppc_core_init_vm_e500,
 517        .destroy_vm = kvmppc_core_destroy_vm_e500,
 518        .emulate_op = kvmppc_core_emulate_op_e500,
 519        .emulate_mtspr = kvmppc_core_emulate_mtspr_e500,
 520        .emulate_mfspr = kvmppc_core_emulate_mfspr_e500,
 521};
 522
 523static int __init kvmppc_e500_init(void)
 524{
 525        int r, i;
 526        unsigned long ivor[3];
 527        /* Process remaining handlers above the generic first 16 */
 528        unsigned long *handler = &kvmppc_booke_handler_addr[16];
 529        unsigned long handler_len;
 530        unsigned long max_ivor = 0;
 531
 532        r = kvmppc_core_check_processor_compat();
 533        if (r)
 534                goto err_out;
 535
 536        r = kvmppc_booke_init();
 537        if (r)
 538                goto err_out;
 539
 540        /* copy extra E500 exception handlers */
 541        ivor[0] = mfspr(SPRN_IVOR32);
 542        ivor[1] = mfspr(SPRN_IVOR33);
 543        ivor[2] = mfspr(SPRN_IVOR34);
 544        for (i = 0; i < 3; i++) {
 545                if (ivor[i] > ivor[max_ivor])
 546                        max_ivor = i;
 547
 548                handler_len = handler[i + 1] - handler[i];
 549                memcpy((void *)kvmppc_booke_handlers + ivor[i],
 550                       (void *)handler[i], handler_len);
 551        }
 552        handler_len = handler[max_ivor + 1] - handler[max_ivor];
 553        flush_icache_range(kvmppc_booke_handlers, kvmppc_booke_handlers +
 554                           ivor[max_ivor] + handler_len);
 555
 556        r = kvm_init(NULL, sizeof(struct kvmppc_vcpu_e500), 0, THIS_MODULE);
 557        if (r)
 558                goto err_out;
 559        kvm_ops_e500.owner = THIS_MODULE;
 560        kvmppc_pr_ops = &kvm_ops_e500;
 561
 562err_out:
 563        return r;
 564}
 565
 566static void __exit kvmppc_e500_exit(void)
 567{
 568        kvmppc_pr_ops = NULL;
 569        kvmppc_booke_exit();
 570}
 571
 572module_init(kvmppc_e500_init);
 573module_exit(kvmppc_e500_exit);
 574MODULE_ALIAS_MISCDEV(KVM_MINOR);
 575MODULE_ALIAS("devname:kvm");
 576