powerpc/kvm/e500.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Copyright (C) 2008-2011 Freescale Semiconductor, Inc. All rights reserved.
0004  *
0005  * Author: Yu Liu, <yu.liu@freescale.com>
0006  *
0007  * Description:
0008  * This file is derived from arch/powerpc/kvm/44x.c,
0009  * by Hollis Blanchard <hollisb@us.ibm.com>.
0010  */
0011
0012 #include <linux/kvm_host.h>
0013 #include <linux/slab.h>
0014 #include <linux/err.h>
0015 #include <linux/export.h>
0016 #include <linux/module.h>
0017 #include <linux/miscdevice.h>
0018
0019 #include <asm/reg.h>
0020 #include <asm/cputable.h>
0021 #include <asm/kvm_ppc.h>
0022
0023 #include "../mm/mmu_decl.h"
0024 #include "booke.h"
0025 #include "e500.h"
0026
0027 struct id {
0028     unsigned long val;
0029     struct id **pentry;
0030 };
0031
0032 #define NUM_TIDS 256
0033
0034 /*
0035  * This table provide mappings from:
0036  * (guestAS,guestTID,guestPR) --> ID of physical cpu
0037  * guestAS  [0..1]
0038  * guestTID [0..255]
0039  * guestPR  [0..1]
0040  * ID       [1..255]
0041  * Each vcpu keeps one vcpu_id_table.
0042  */
0043 struct vcpu_id_table {
0044     struct id id[2][NUM_TIDS][2];
0045 };
0046
0047 /*
0048  * This table provide reversed mappings of vcpu_id_table:
0049  * ID --> address of vcpu_id_table item.
0050  * Each physical core has one pcpu_id_table.
0051  */
0052 struct pcpu_id_table {
0053     struct id *entry[NUM_TIDS];
0054 };
0055
0056 static DEFINE_PER_CPU(struct pcpu_id_table, pcpu_sids);
0057
0058 /* This variable keeps last used shadow ID on local core.
0059  * The valid range of shadow ID is [1..255] */
0060 static DEFINE_PER_CPU(unsigned long, pcpu_last_used_sid);
0061
0062 /*
0063  * Allocate a free shadow id and setup a valid sid mapping in given entry.
0064  * A mapping is only valid when vcpu_id_table and pcpu_id_table are match.
0065  *
0066  * The caller must have preemption disabled, and keep it that way until
0067  * it has finished with the returned shadow id (either written into the
0068  * TLB or arch.shadow_pid, or discarded).
0069  */
0070 static inline int local_sid_setup_one(struct id *entry)
0071 {
0072     unsigned long sid;
0073     int ret = -1;
0074
0075     sid = __this_cpu_inc_return(pcpu_last_used_sid);
0076     if (sid < NUM_TIDS) {
0077         __this_cpu_write(pcpu_sids.entry[sid], entry);
0078         entry->val = sid;
0079         entry->pentry = this_cpu_ptr(&pcpu_sids.entry[sid]);
0080         ret = sid;
0081     }
0082
0083     /*
0084      * If sid == NUM_TIDS, we've run out of sids.  We return -1, and
0085      * the caller will invalidate everything and start over.
0086      *
0087      * sid > NUM_TIDS indicates a race, which we disable preemption to
0088      * avoid.
0089      */
0090     WARN_ON(sid > NUM_TIDS);
0091
0092     return ret;
0093 }
0094
0095 /*
0096  * Check if given entry contain a valid shadow id mapping.
0097  * An ID mapping is considered valid only if
0098  * both vcpu and pcpu know this mapping.
0099  *
0100  * The caller must have preemption disabled, and keep it that way until
0101  * it has finished with the returned shadow id (either written into the
0102  * TLB or arch.shadow_pid, or discarded).
0103  */
0104 static inline int local_sid_lookup(struct id *entry)
0105 {
0106     if (entry && entry->val != 0 &&
0107         __this_cpu_read(pcpu_sids.entry[entry->val]) == entry &&
0108         entry->pentry == this_cpu_ptr(&pcpu_sids.entry[entry->val]))
0109         return entry->val;
0110     return -1;
0111 }
0112
0113 /* Invalidate all id mappings on local core -- call with preempt disabled */
0114 static inline void local_sid_destroy_all(void)
0115 {
0116     __this_cpu_write(pcpu_last_used_sid, 0);
0117     memset(this_cpu_ptr(&pcpu_sids), 0, sizeof(pcpu_sids));
0118 }
0119
0120 static void *kvmppc_e500_id_table_alloc(struct kvmppc_vcpu_e500 *vcpu_e500)
0121 {
0122     vcpu_e500->idt = kzalloc(sizeof(struct vcpu_id_table), GFP_KERNEL);
0123     return vcpu_e500->idt;
0124 }
0125
0126 static void kvmppc_e500_id_table_free(struct kvmppc_vcpu_e500 *vcpu_e500)
0127 {
0128     kfree(vcpu_e500->idt);
0129     vcpu_e500->idt = NULL;
0130 }
0131
0132 /* Map guest pid to shadow.
0133  * We use PID to keep shadow of current guest non-zero PID,
0134  * and use PID1 to keep shadow of guest zero PID.
0135  * So that guest tlbe with TID=0 can be accessed at any time */
0136 static void kvmppc_e500_recalc_shadow_pid(struct kvmppc_vcpu_e500 *vcpu_e500)
0137 {
0138     preempt_disable();
0139     vcpu_e500->vcpu.arch.shadow_pid = kvmppc_e500_get_sid(vcpu_e500,
0140             get_cur_as(&vcpu_e500->vcpu),
0141             get_cur_pid(&vcpu_e500->vcpu),
0142             get_cur_pr(&vcpu_e500->vcpu), 1);
0143     vcpu_e500->vcpu.arch.shadow_pid1 = kvmppc_e500_get_sid(vcpu_e500,
0144             get_cur_as(&vcpu_e500->vcpu), 0,
0145             get_cur_pr(&vcpu_e500->vcpu), 1);
0146     preempt_enable();
0147 }
0148
0149 /* Invalidate all mappings on vcpu */
0150 static void kvmppc_e500_id_table_reset_all(struct kvmppc_vcpu_e500 *vcpu_e500)
0151 {
0152     memset(vcpu_e500->idt, 0, sizeof(struct vcpu_id_table));
0153
0154     /* Update shadow pid when mappings are changed */
0155     kvmppc_e500_recalc_shadow_pid(vcpu_e500);
0156 }
0157
0158 /* Invalidate one ID mapping on vcpu */
0159 static inline void kvmppc_e500_id_table_reset_one(
0160                    struct kvmppc_vcpu_e500 *vcpu_e500,
0161                    int as, int pid, int pr)
0162 {
0163     struct vcpu_id_table *idt = vcpu_e500->idt;
0164
0165     BUG_ON(as >= 2);
0166     BUG_ON(pid >= NUM_TIDS);
0167     BUG_ON(pr >= 2);
0168
0169     idt->id[as][pid][pr].val = 0;
0170     idt->id[as][pid][pr].pentry = NULL;
0171
0172     /* Update shadow pid when mappings are changed */
0173     kvmppc_e500_recalc_shadow_pid(vcpu_e500);
0174 }
0175
0176 /*
0177  * Map guest (vcpu,AS,ID,PR) to physical core shadow id.
0178  * This function first lookup if a valid mapping exists,
0179  * if not, then creates a new one.
0180  *
0181  * The caller must have preemption disabled, and keep it that way until
0182  * it has finished with the returned shadow id (either written into the
0183  * TLB or arch.shadow_pid, or discarded).
0184  */
0185 unsigned int kvmppc_e500_get_sid(struct kvmppc_vcpu_e500 *vcpu_e500,
0186                  unsigned int as, unsigned int gid,
0187                  unsigned int pr, int avoid_recursion)
0188 {
0189     struct vcpu_id_table *idt = vcpu_e500->idt;
0190     int sid;
0191
0192     BUG_ON(as >= 2);
0193     BUG_ON(gid >= NUM_TIDS);
0194     BUG_ON(pr >= 2);
0195
0196     sid = local_sid_lookup(&idt->id[as][gid][pr]);
0197
0198     while (sid <= 0) {
0199         /* No mapping yet */
0200         sid = local_sid_setup_one(&idt->id[as][gid][pr]);
0201         if (sid <= 0) {
0202             _tlbil_all();
0203             local_sid_destroy_all();
0204         }
0205
0206         /* Update shadow pid when mappings are changed */
0207         if (!avoid_recursion)
0208             kvmppc_e500_recalc_shadow_pid(vcpu_e500);
0209     }
0210
0211     return sid;
0212 }
0213
0214 unsigned int kvmppc_e500_get_tlb_stid(struct kvm_vcpu *vcpu,
0215                       struct kvm_book3e_206_tlb_entry *gtlbe)
0216 {
0217     return kvmppc_e500_get_sid(to_e500(vcpu), get_tlb_ts(gtlbe),
0218                    get_tlb_tid(gtlbe), get_cur_pr(vcpu), 0);
0219 }
0220
0221 void kvmppc_set_pid(struct kvm_vcpu *vcpu, u32 pid)
0222 {
0223     struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
0224
0225     if (vcpu->arch.pid != pid) {
0226         vcpu_e500->pid[0] = vcpu->arch.pid = pid;
0227         kvmppc_e500_recalc_shadow_pid(vcpu_e500);
0228     }
0229 }
0230
0231 /* gtlbe must not be mapped by more than one host tlbe */
0232 void kvmppc_e500_tlbil_one(struct kvmppc_vcpu_e500 *vcpu_e500,
0233                            struct kvm_book3e_206_tlb_entry *gtlbe)
0234 {
0235     struct vcpu_id_table *idt = vcpu_e500->idt;
0236     unsigned int pr, tid, ts;
0237     int pid;
0238     u32 val, eaddr;
0239     unsigned long flags;
0240
0241     ts = get_tlb_ts(gtlbe);
0242     tid = get_tlb_tid(gtlbe);
0243
0244     preempt_disable();
0245
0246     /* One guest ID may be mapped to two shadow IDs */
0247     for (pr = 0; pr < 2; pr++) {
0248         /*
0249          * The shadow PID can have a valid mapping on at most one
0250          * host CPU.  In the common case, it will be valid on this
0251          * CPU, in which case we do a local invalidation of the
0252          * specific address.
0253          *
0254          * If the shadow PID is not valid on the current host CPU,
0255          * we invalidate the entire shadow PID.
0256          */
0257         pid = local_sid_lookup(&idt->id[ts][tid][pr]);
0258         if (pid <= 0) {
0259             kvmppc_e500_id_table_reset_one(vcpu_e500, ts, tid, pr);
0260             continue;
0261         }
0262
0263         /*
0264          * The guest is invalidating a 4K entry which is in a PID
0265          * that has a valid shadow mapping on this host CPU.  We
0266          * search host TLB to invalidate it's shadow TLB entry,
0267          * similar to __tlbil_va except that we need to look in AS1.
0268          */
0269         val = (pid << MAS6_SPID_SHIFT) | MAS6_SAS;
0270         eaddr = get_tlb_eaddr(gtlbe);
0271
0272         local_irq_save(flags);
0273
0274         mtspr(SPRN_MAS6, val);
0275         asm volatile("tlbsx 0, %[eaddr]" : : [eaddr] "r" (eaddr));
0276         val = mfspr(SPRN_MAS1);
0277         if (val & MAS1_VALID) {
0278             mtspr(SPRN_MAS1, val & ~MAS1_VALID);
0279             asm volatile("tlbwe");
0280         }
0281
0282         local_irq_restore(flags);
0283     }
0284
0285     preempt_enable();
0286 }
0287
0288 void kvmppc_e500_tlbil_all(struct kvmppc_vcpu_e500 *vcpu_e500)
0289 {
0290     kvmppc_e500_id_table_reset_all(vcpu_e500);
0291 }
0292
0293 void kvmppc_mmu_msr_notify(struct kvm_vcpu *vcpu, u32 old_msr)
0294 {
0295     /* Recalc shadow pid since MSR changes */
0296     kvmppc_e500_recalc_shadow_pid(to_e500(vcpu));
0297 }
0298
0299 static void kvmppc_core_vcpu_load_e500(struct kvm_vcpu *vcpu, int cpu)
0300 {
0301     kvmppc_booke_vcpu_load(vcpu, cpu);
0302
0303     /* Shadow PID may be expired on local core */
0304     kvmppc_e500_recalc_shadow_pid(to_e500(vcpu));
0305 }
0306
0307 static void kvmppc_core_vcpu_put_e500(struct kvm_vcpu *vcpu)
0308 {
0309 #ifdef CONFIG_SPE
0310     if (vcpu->arch.shadow_msr & MSR_SPE)
0311         kvmppc_vcpu_disable_spe(vcpu);
0312 #endif
0313
0314     kvmppc_booke_vcpu_put(vcpu);
0315 }
0316
0317 int kvmppc_core_check_processor_compat(void)
0318 {
0319     int r;
0320
0321     if (strcmp(cur_cpu_spec->cpu_name, "e500v2") == 0)
0322         r = 0;
0323     else
0324         r = -ENOTSUPP;
0325
0326     return r;
0327 }
0328
0329 static void kvmppc_e500_tlb_setup(struct kvmppc_vcpu_e500 *vcpu_e500)
0330 {
0331     struct kvm_book3e_206_tlb_entry *tlbe;
0332
0333     /* Insert large initial mapping for guest. */
0334     tlbe = get_entry(vcpu_e500, 1, 0);
0335     tlbe->mas1 = MAS1_VALID | MAS1_TSIZE(BOOK3E_PAGESZ_256M);
0336     tlbe->mas2 = 0;
0337     tlbe->mas7_3 = E500_TLB_SUPER_PERM_MASK;
0338
0339     /* 4K map for serial output. Used by kernel wrapper. */
0340     tlbe = get_entry(vcpu_e500, 1, 1);
0341     tlbe->mas1 = MAS1_VALID | MAS1_TSIZE(BOOK3E_PAGESZ_4K);
0342     tlbe->mas2 = (0xe0004500 & 0xFFFFF000) | MAS2_I | MAS2_G;
0343     tlbe->mas7_3 = (0xe0004500 & 0xFFFFF000) | E500_TLB_SUPER_PERM_MASK;
0344 }
0345
0346 int kvmppc_core_vcpu_setup(struct kvm_vcpu *vcpu)
0347 {
0348     struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
0349
0350     kvmppc_e500_tlb_setup(vcpu_e500);
0351
0352     /* Registers init */
0353     vcpu->arch.pvr = mfspr(SPRN_PVR);
0354     vcpu_e500->svr = mfspr(SPRN_SVR);
0355
0356     vcpu->arch.cpu_type = KVM_CPU_E500V2;
0357
0358     return 0;
0359 }
0360
0361 static int kvmppc_core_get_sregs_e500(struct kvm_vcpu *vcpu,
0362                       struct kvm_sregs *sregs)
0363 {
0364     struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
0365
0366     sregs->u.e.features |= KVM_SREGS_E_ARCH206_MMU | KVM_SREGS_E_SPE |
0367                            KVM_SREGS_E_PM;
0368     sregs->u.e.impl_id = KVM_SREGS_E_IMPL_FSL;
0369
0370     sregs->u.e.impl.fsl.features = 0;
0371     sregs->u.e.impl.fsl.svr = vcpu_e500->svr;
0372     sregs->u.e.impl.fsl.hid0 = vcpu_e500->hid0;
0373     sregs->u.e.impl.fsl.mcar = vcpu_e500->mcar;
0374
0375     sregs->u.e.ivor_high[0] = vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_UNAVAIL];
0376     sregs->u.e.ivor_high[1] = vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_FP_DATA];
0377     sregs->u.e.ivor_high[2] = vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_FP_ROUND];
0378     sregs->u.e.ivor_high[3] =
0379         vcpu->arch.ivor[BOOKE_IRQPRIO_PERFORMANCE_MONITOR];
0380
0381     kvmppc_get_sregs_ivor(vcpu, sregs);
0382     kvmppc_get_sregs_e500_tlb(vcpu, sregs);
0383     return 0;
0384 }
0385
0386 static int kvmppc_core_set_sregs_e500(struct kvm_vcpu *vcpu,
0387                       struct kvm_sregs *sregs)
0388 {
0389     struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
0390     int ret;
0391
0392     if (sregs->u.e.impl_id == KVM_SREGS_E_IMPL_FSL) {
0393         vcpu_e500->svr = sregs->u.e.impl.fsl.svr;
0394         vcpu_e500->hid0 = sregs->u.e.impl.fsl.hid0;
0395         vcpu_e500->mcar = sregs->u.e.impl.fsl.mcar;
0396     }
0397
0398     ret = kvmppc_set_sregs_e500_tlb(vcpu, sregs);
0399     if (ret < 0)
0400         return ret;
0401
0402     if (!(sregs->u.e.features & KVM_SREGS_E_IVOR))
0403         return 0;
0404
0405     if (sregs->u.e.features & KVM_SREGS_E_SPE) {
0406         vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_UNAVAIL] =
0407             sregs->u.e.ivor_high[0];
0408         vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_FP_DATA] =
0409             sregs->u.e.ivor_high[1];
0410         vcpu->arch.ivor[BOOKE_IRQPRIO_SPE_FP_ROUND] =
0411             sregs->u.e.ivor_high[2];
0412     }
0413
0414     if (sregs->u.e.features & KVM_SREGS_E_PM) {
0415         vcpu->arch.ivor[BOOKE_IRQPRIO_PERFORMANCE_MONITOR] =
0416             sregs->u.e.ivor_high[3];
0417     }
0418
0419     return kvmppc_set_sregs_ivor(vcpu, sregs);
0420 }
0421
0422 static int kvmppc_get_one_reg_e500(struct kvm_vcpu *vcpu, u64 id,
0423                    union kvmppc_one_reg *val)
0424 {
0425     int r = kvmppc_get_one_reg_e500_tlb(vcpu, id, val);
0426     return r;
0427 }
0428
0429 static int kvmppc_set_one_reg_e500(struct kvm_vcpu *vcpu, u64 id,
0430                    union kvmppc_one_reg *val)
0431 {
0432     int r = kvmppc_get_one_reg_e500_tlb(vcpu, id, val);
0433     return r;
0434 }
0435
0436 static int kvmppc_core_vcpu_create_e500(struct kvm_vcpu *vcpu)
0437 {
0438     struct kvmppc_vcpu_e500 *vcpu_e500;
0439     int err;
0440
0441     BUILD_BUG_ON(offsetof(struct kvmppc_vcpu_e500, vcpu) != 0);
0442     vcpu_e500 = to_e500(vcpu);
0443
0444     if (kvmppc_e500_id_table_alloc(vcpu_e500) == NULL)
0445         return -ENOMEM;
0446
0447     err = kvmppc_e500_tlb_init(vcpu_e500);
0448     if (err)
0449         goto uninit_id;
0450
0451     vcpu->arch.shared = (void*)__get_free_page(GFP_KERNEL|__GFP_ZERO);
0452     if (!vcpu->arch.shared) {
0453         err = -ENOMEM;
0454         goto uninit_tlb;
0455     }
0456
0457     return 0;
0458
0459 uninit_tlb:
0460     kvmppc_e500_tlb_uninit(vcpu_e500);
0461 uninit_id:
0462     kvmppc_e500_id_table_free(vcpu_e500);
0463     return err;
0464 }
0465
0466 static void kvmppc_core_vcpu_free_e500(struct kvm_vcpu *vcpu)
0467 {
0468     struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
0469
0470     free_page((unsigned long)vcpu->arch.shared);
0471     kvmppc_e500_tlb_uninit(vcpu_e500);
0472     kvmppc_e500_id_table_free(vcpu_e500);
0473 }
0474
0475 static int kvmppc_core_init_vm_e500(struct kvm *kvm)
0476 {
0477     return 0;
0478 }
0479
0480 static void kvmppc_core_destroy_vm_e500(struct kvm *kvm)
0481 {
0482 }
0483
0484 static struct kvmppc_ops kvm_ops_e500 = {
0485     .get_sregs = kvmppc_core_get_sregs_e500,
0486     .set_sregs = kvmppc_core_set_sregs_e500,
0487     .get_one_reg = kvmppc_get_one_reg_e500,
0488     .set_one_reg = kvmppc_set_one_reg_e500,
0489     .vcpu_load   = kvmppc_core_vcpu_load_e500,
0490     .vcpu_put    = kvmppc_core_vcpu_put_e500,
0491     .vcpu_create = kvmppc_core_vcpu_create_e500,
0492     .vcpu_free   = kvmppc_core_vcpu_free_e500,
0493     .init_vm = kvmppc_core_init_vm_e500,
0494     .destroy_vm = kvmppc_core_destroy_vm_e500,
0495     .emulate_op = kvmppc_core_emulate_op_e500,
0496     .emulate_mtspr = kvmppc_core_emulate_mtspr_e500,
0497     .emulate_mfspr = kvmppc_core_emulate_mfspr_e500,
0498     .create_vcpu_debugfs = kvmppc_create_vcpu_debugfs_e500,
0499 };
0500
0501 static int __init kvmppc_e500_init(void)
0502 {
0503     int r, i;
0504     unsigned long ivor[3];
0505     /* Process remaining handlers above the generic first 16 */
0506     unsigned long *handler = &kvmppc_booke_handler_addr[16];
0507     unsigned long handler_len;
0508     unsigned long max_ivor = 0;
0509
0510     r = kvmppc_core_check_processor_compat();
0511     if (r)
0512         goto err_out;
0513
0514     r = kvmppc_booke_init();
0515     if (r)
0516         goto err_out;
0517
0518     /* copy extra E500 exception handlers */
0519     ivor[0] = mfspr(SPRN_IVOR32);
0520     ivor[1] = mfspr(SPRN_IVOR33);
0521     ivor[2] = mfspr(SPRN_IVOR34);
0522     for (i = 0; i < 3; i++) {
0523         if (ivor[i] > ivor[max_ivor])
0524             max_ivor = i;
0525
0526         handler_len = handler[i + 1] - handler[i];
0527         memcpy((void *)kvmppc_booke_handlers + ivor[i],
0528                (void *)handler[i], handler_len);
0529     }
0530     handler_len = handler[max_ivor + 1] - handler[max_ivor];
0531     flush_icache_range(kvmppc_booke_handlers, kvmppc_booke_handlers +
0532                ivor[max_ivor] + handler_len);
0533
0534     r = kvm_init(NULL, sizeof(struct kvmppc_vcpu_e500), 0, THIS_MODULE);
0535     if (r)
0536         goto err_out;
0537     kvm_ops_e500.owner = THIS_MODULE;
0538     kvmppc_pr_ops = &kvm_ops_e500;
0539
0540 err_out:
0541     return r;
0542 }
0543
0544 static void __exit kvmppc_e500_exit(void)
0545 {
0546     kvmppc_pr_ops = NULL;
0547     kvmppc_booke_exit();
0548 }
0549
0550 module_init(kvmppc_e500_init);
0551 module_exit(kvmppc_e500_exit);
0552 MODULE_ALIAS_MISCDEV(KVM_MINOR);
0553 MODULE_ALIAS("devname:kvm");